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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: Platinumfungi on June 16, 2007, 08:35:41 AM

Title: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Platinumfungi on June 16, 2007, 08:35:41 AM
Here's a complete chart of all the SMD electrolytic capacitors in the Turbo Duo and PC Engine Duo for reference purposes. Hopefully this will help individuals involved in Duo repair and troubleshooting. 

The SMD electrolytic capacitor layout is identical on both the Turbo Duo and PC Engine Duo, so this chart can be used for either system.

I hope to eventually add individual voltage ratings,  but for now - if you use all 16V except for the 50V by the cd-rom you'll be fine.

Questions and comments welcome.

Cap Replacement Chart for the Turbo Duo and PC Engine Duo:
(http://pic.photobucket.com/bwe.png)

Title: Re: PC Engine Duo total capacitor replacement chart
Post by: Mobius on June 16, 2007, 09:03:50 AM
That's cool.  Just going off of memory, I think that's exactly the same as the US Duo, too.  But I'd have to open mine up to confirm it.
Title: Re: PC Engine Duo total capacitor replacement chart
Post by: Turbo D on June 16, 2007, 12:49:58 PM
Thanks man, thats awesome! Ya, its the same as the US duo except the US duo has a big metal plate covering some stuff.

Title: Re: PC Engine Duo total capacitor replacement chart
Post by: grahf on June 16, 2007, 01:30:30 PM
Great job. This is useful info to have around. I havn't checked one personally, but ive heard that the Duo-R and RX are identicle inside. Supposedly the only real difference is the inclusion of the arcade pad with the RX. Maybe somebody can verify.
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: Air_Zonk on June 20, 2007, 07:05:18 PM
Wow! This site has really stripped away much of the intimidation that goes along with the idea of repairing Turbo items. If anyone decides to do a Turbo Express/ PCE GT chart, that would be much appreciated. :dance:

Anyone have a good/inexpensive Multi Meter suggestion?
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: Platinumfungi on June 21, 2007, 12:48:21 PM
I'm willing to do a chart on any system, but I don't have a PCE or portable at my disposal.... If I did I'd happily map out the caps for you.  Any others you'd like to see? 
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: SignOfZeta on June 21, 2007, 02:46:10 PM
Quote from: Air_Zonk
Anyone have a good/inexpensive Multi Meter suggestion?

Sears makes a pretty decent Craftsman branded one for $40 that I'd recommend. The ones cheaper than that you generally want to avoid since they don't have the same 10MΩ impedance the $40 one has, and long story short that's a good thing to have to avoid frying things like computer chips, and the meter itself.
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: Air_Zonk on June 22, 2007, 06:15:42 PM
There are a bunch of different $40 meters HERE (http://www.sears.com/sr/javasr/search.do?BV_UseBVCookie=Yes&compare=&sort=&vertical=TOOL&beginValue=&keyword=multi+meter&sortBy=PRICE_HIGH_TO_LOW&viewItems=20&order=&pageNum=2&subcategoryid=&endValue=&page=&catID=) on the SEARS site. I am pretty lost when it comes to purchasing one of these, I don't even know what "10MΩ impedance" means. There's 9 different meters ranging from $30-$50. Can someone recommend one on the page? I'm ready to dive into my defective PCE GT and replace the faulty capacitor(s)!!! Some guidance would be much appreciated, thanks!
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: nat on June 22, 2007, 06:53:36 PM
I hope you have small and steady fingers.

I had an absolute NIGHTMARE with my GT. I gave up after only replacing 1 cap. I blew the fuse in the process.

At least I got the audio working through headphones.
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: Air_Zonk on June 23, 2007, 04:51:56 AM
I wouldn't be asking questions if I didn't think I could do it. I'm obviously new to these kind of repairs, but I'm not a stranger to a soldering iron. Any real help would be great!
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: nat on June 23, 2007, 09:35:22 AM
There's not much to say other than what I mentioned in my last message.

The TE/GT repair is one of the hardest soldering jobs I've ever attempted due to the extreme proximity of ICs and caps on the PCB. This was compounded, for me, by large and unsteady fingers. The TE/GT is incredibly cramped inside. The PCB is small and everything is extremely close together. When you first get the screws out and are seperating the two "halves" be careful in disconnecting the ribbon cables. They tear easily. After you're done with the repairs, make sure nothing will short out when you power back on before you put it back together. Otherwise you will blow the fuse.

There's another thread in this very forum that has pictures and step-by-step instructions on what exactly needs to be replaced so I won't rehash that here.

Beyond that, all I can say is "Good luck" and your mileage may vary.
Title: Capacitor Replacement
Post by: Air_Zonk on June 23, 2007, 08:53:41 PM
But here's the thing, nothing you posted answered any of my concerns... This thread involves capacitor replacement and I'm not trying to derail the importance of that. You obviously must have misunderstood my posts, because all I am simply asking for is a recommendation on a Multi Meter and to hopefully get some clarification on what the reference "10MΩ impedance" meant… :-s
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: nat on June 23, 2007, 09:52:31 PM
I read the following statement:

I'm ready to dive into my defective PCE GT and replace the faulty capacitor(s)!!! Some guidance would be much appreciated, thanks!

And assumed you were asking for guidance regarding replacing the caps.
Title: Re: Capacitor Replacement
Post by: SignOfZeta on June 24, 2007, 02:33:51 AM
But here's the thing, nothing you posted answered any of my concerns... This thread involves capacitor replacement and I'm not trying to derail the importance of that. You obviously must have misunderstood my posts, because all I am simply asking for is a recommendation on a Multi Meter and to hopefully get some clarification on what the reference "10MΩ impedance" meant… :-s


When you use the voltmeter mode of a DMM (or any mode other than ammeter mode, since the other modes are just variations on voltmeter mode) you are measuring the difference in voltage between two points. In doing so you are making a complete circuit with the meter. Because of this its important that the meter have a high internal resistance to avoid creating a near short condition and allowing too much current to flow through the meter, and the two points on the circuit you are testing. If a meter says it has an impedence of 10MΩ  (10,000 ohms) then it's far too thick to make any meaningful/dangerous short circuit using household, or automotive levels of power. IN this situation the DMM is basically tranparent to the circuit, and has zero effect on it. Now, this doesn't apply to ammeter mode. Incorrect use of a DMM in ammeter mode will blow the meter's fuse, or something worse.

The meter I bought from Sears years ago seems to be no longer made, but this one is kind of close.

http://www.sears.com/sr/javasr/product.do?cat=Electrical+Shop&pid=03482139000&vertical=TOOL&subcat=Multi-Meters%2C+Testers+%26+Accessories&BV_UseBVCookie=Yes

It claims 7.5MΩ impedance, which is certainly enough security for things like a TG-16. The impedance ratings aren't mentioned in the "stats" section on Sears' website, but if you look at the owners manual PDF they provide, its usually listed there. If it isn't mentioned on a cheap meter, assume its a terrible rating.

BTW, replacing these capacitors is going to suck. Not because of the tiny work spaces, but you are going to have to be really really careful not to pull any tracing off the board when you remove the old components.
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: Platinumfungi on June 27, 2007, 10:15:21 AM
I found some updates that I need to make to the chart. I'll be adding them as soon as I can. 
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: nodtveidt on June 27, 2007, 12:28:21 PM
What's with the hideous watermark? #-o Got a clean version? :pray:
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: Platinumfungi on June 27, 2007, 02:56:57 PM
I hate watermarks too, but I feel that the time I have invested is worth one.  It's just so people don't try to pass it off as their own work.  I don't think it hinders the chart but I'm open to constructive criticism.
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: nodtveidt on June 27, 2007, 03:38:49 PM
Do you think you could email or PM me a clean version? I'd like to have a printout of it for my binder, but the watermark just bugs me, heh. :D

If not, then well...I'll do something else. :cry:
Title: Re: USA and PC Engine Duo total capacitor replacement chart
Post by: Platinumfungi on June 28, 2007, 12:31:35 AM
Well I could try and lighten it a bit more if that would help you out?  Don't print one off yet though as I have just added an edit yesterday that I found some more info I missed on my chart and will more then likely have separate charts for the US and the PC Duos very soon. 

Edit - Chart updated and the water mark has been slightly lightened.
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: Platinumfungi on July 23, 2007, 12:50:02 PM
Just added some more info. Let me know if you need anything else or have questions.
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: SNKNostalgia on July 23, 2007, 01:25:53 PM
Here is one thing though. Would it be a better idea to replace the caps that function for the CD-Rom drive first and then buy a Hop M3 laser if there still is a problem with the disks reading?

Also, what caps function for the CD-Drive? I find it funny how Duo-Rs use the same exact drive but different board layout with less functioning issues. It must be a cap issue, or just how the controller part works for the CD drive.
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: Turbo D on July 23, 2007, 01:30:41 PM
My U.S. duo pcb has both those insulated wire holding legs and is missing the ceramic disk capacitor. Also, it has that one part on the bottom with the pad, like the pc engine. Do you think my U.S. duo is earlier or later model?
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: Platinumfungi on July 23, 2007, 03:00:56 PM
SNK -  Unfortunately I don't know which caps regulate which areas of the system.  I'm new to working on NEC systems so I had been following D-Lite's suggestions on the audio replacement. I still had issues so I decided to randomly replace two at a time and then test. I eventually replaced two that got my cd audio going only to find it gone again later. I continued to have problems until I replaced one other specific cap and then it seemed fine. I can point out the three caps that most effected my PC Engine's audio but it could just be that those caps were going bad on my system and might not be of any use to anyone else.  I was going nice and slow and charting my results but unfortunately I'm fixing this system for someone else and so my deadline came up and I had to hurry along.  I'd love to have a chart that shows which caps relate to which part of the system if anyone/everyone could figure it out....

Turbo D - So....perhaps it's not the difference between US and PCE but an earlier or later model eh?  Sounds like we should both check the model numbers and compare.

I edited my post slightly to try to figure out what the real reason is for the differences on the pcbs.
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: Turbo D on July 23, 2007, 09:18:33 PM
The model number on my U.S. Turbo duo pcb is "L61-I-280IY." The serial number on the plastic case is "28011731A." It says under the serial number that it was manufactured August 1992.
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: SNKNostalgia on July 26, 2007, 07:28:50 PM
My Duo is a March 93 model and resembles the typical US model. Serial 33000254A. Will look at the PCB later on, playing my system right now and really far into Legendary Axe.
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: Platinumfungi on July 28, 2007, 08:17:46 AM
The PC Engine Duo from the pics:

PCB # - L31-4-2804B
Serial # - 28008251B
CD-ROM # -02920618
No sticker on the bottom for manufactured date.

The US Duo from the pics:

PCB # - L61-2-3107AV
Serial # - 31024101A
CD-ROM # -02921107
Manufactured - January 1993
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: agt_dale_cooper on December 07, 2008, 05:12:23 PM
Holy Bananas, Nat quoted this original posting.

Yes, Red Ghost, this is the one I wanted to see the volts updated on...[and, as long as I've got everyone's attention by necroposting this, both this chart AND the Express charts are WORKS OF ART according to us folk who like to repair stuff and both deserve to be stickied...how does one access this functionality?  I see the buttons at the bottom of the main page, but.........?]

[Special Agent Dale Cooper (http://en.wikipedia.org/wiki/Dale_Cooper) adds his name to the list of folks who have appreciated your efforts....]
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: Platinumfungi on December 09, 2008, 03:01:33 PM
Holy Bananas, Nat quoted this original posting.

Yes, Red Ghost, this is the one I wanted to see the volts updated on...[and, as long as I've got everyone's attention by necroposting this, both this chart AND the Express charts are WORKS OF ART according to us folk who like to repair stuff and both deserve to be stickied...how does one access this functionality?  I see the buttons at the bottom of the main page, but.........?]

[Special Agent Dale Cooper (http://en.wikipedia.org/wiki/Dale_Cooper) adds his name to the list of folks who have appreciated your efforts....]


Hey thanks :D

It's nice to hear someone finds it useful. When I first posted it a few people gave comments, but I didn't know if many people were actually using it/finding it useful.

I'll see if I can update it in the next few days. I'm going out of town till New Years soon, so if you don't see it updated in the next week, I'll get it done early January.

I've also thought about making charts for the other NEC systems, but I think they would be of less use as the Duo and Express (and variants) are the most problematic it seems.
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: nick3092 on December 10, 2008, 10:48:22 PM

Hey thanks :D

It's nice to hear someone finds it useful. When I first posted it a few people gave comments, but I didn't know if many people were actually using it/finding it useful.

I used it to do a total cap replacement on my US Duo as well, and it was a lifesaver.  Just printed it out, and laid it on the workbench next to me.  Only question I have though, unless I'm missing something - the key has a 3.3uf cap listed, but I don't see it marked anywhere on the board.  Where is it?
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: Necromancer on December 11, 2008, 01:24:14 AM
Only question I have though, unless I'm missing something - the key has a 3.3uf cap listed, but I don't see it marked anywhere on the board.  Where is it?

Right below the laser and above a pair of 22uF caps.  :wink:
Title: Re: Updated 7/23/07 - US and PC Engine Duo total capacitor replacement chart +
Post by: nick3092 on December 11, 2008, 10:19:11 AM
Right below the laser and above a pair of 22uF caps.  :wink:

Wow, do I feel like an idiot.  Between it being under the wires and the plastic holding the wires down, I never physically saw it on the board.  And it just blended into the picture.  Well, it works as is.  But considering I replaced all the other caps, and I have the 3.3 sitting here, I might as well replace it.  Eh, this weekend.
Title: Re: USA / PCE Turbo Duo - total capacitor replacement chart
Post by: Platinumfungi on December 11, 2008, 11:40:16 AM
Make sure to note the voltage of that cap when you remove the old one. From what I recall (and will update as soon as I can) the voltage on that cap was really high. Like 50V.
Title: Re: USA / PCE Turbo Duo - total capacitor replacement chart
Post by: nick3092 on December 11, 2008, 01:11:08 PM
Yeah, it says:

3.3
50
20

on the top.  Luckily the 3.3 I ordered was a 50.
Title: Re: USA / PCE Turbo Duo - total capacitor replacement chart
Post by: Platinumfungi on December 11, 2008, 01:17:20 PM
Yeah, it says:

3.3
50
20

on the top.  Luckily the 3.3 I ordered was a 50.

Great! You should be all set then.
Title: Re: USA / PCE Turbo Duo - total capacitor replacement chart
Post by: Duo_R on December 11, 2008, 04:35:39 PM
is the 3.3 the memory backup "battery" cap?
Title: Re: USA / PCE Turbo Duo - total capacitor replacement chart
Post by: nat on December 13, 2008, 08:10:30 PM
is the 3.3 the memory backup "battery" cap?

Negative. The backup battery is the component directly to the right of the yellow-circled component in the second pic.
Title: Re: USA / PCE Turbo Duo - total capacitor replacement chart
Post by: Platinumfungi on December 14, 2008, 10:50:27 AM
Did a little update. Tried to clean the post up a bit and make the 1st chart a bit nicer. Will add the rest of the voltage ratings and other things after New Years. Enjoy :D
Title: Re: USA / PCE Turbo Duo - total capacitor replacement chart
Post by: agt_dale_cooper on December 14, 2008, 04:41:27 PM
While I'm not one to reengineer 'works of art', isn't the new background rougher on the color cartridge?
Is plain white out of the question?
Color is REQUIRED for this printout, but really only for the board itself where the different color marks are...perhaps this brilliant new blue could take the place of the grey 3.3V that another member already commented he didn't see..perhaps this new hue would be more appropriate there?

For whatever it's worth, I disagree with the watermarking issue...to an extent.  Yours was originally rather large, but is now easily cropped out.  How about a nice little line along the space/trace lines above the HuCard slot?  For more style points, take out the "L31-XX-2804B" and replace with text/watermark of your choice...."All your PC Engine are belong to www.pcenginefx.com (http://www.pcenginefx.com/)!"  HAHAHAHAHAHAHAHAHAHAHAHAHAHAHA!!!!!!!
It'll go with my t-shirt:  http://www.thinkgeek.com/tshirts-apparel/unisex/gaming/3777/?cpg=ab

All comments herein intended as non-insulting / constructive...  O:)

Enjoy your time away for the holidays, I hope to have more progress on this sound issue by the time you return, I've another JAP unit on it's way here, gonna compare apples and apples....
Title: Re: USA / PCE Turbo Duo - total capacitor replacement chart
Post by: Platinumfungi on December 15, 2008, 03:08:46 AM
isn't the new background rougher on the color cartridge?
Is plain white out of the question?
Color is REQUIRED for this printout

Good point. I hadn't thought about printing it out. I usually just reference these off my computer. I've made the change.

the watermarking issue...

I put the name/website at the bottom so that people who are bothered by it can remove it for printing. However, there are multiple water marks in the image. Only one of which I think is even distinguishable to the eye. I set it up this way so that hopefully most people will be happy with it, including myself.


Enjoy your time away for the holidays, I hope to have more progress on this sound issue by the time you return, I've another JAP unit on it's way here, gonna compare apples and apples....

Thanks, and good luck.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Zeon on March 21, 2009, 01:37:54 PM
Edit: Nevermind, it's .047 farads, not microfarads, which is 47000 microfarads, which is pretty big for a cap for being in a duo. I'll have to order some.

There is an odd type cap I have circled in red in the picture. I don't know what type it is specifically it looks like it is some special type as NEC is silk screened on it. It might be a high quality cap used to filter the audio. I can tell you it is a 5.5 volt polarized .047 microfarad cap (it says 473 on it, the 3 being the decimal place), but beyond that I don't know anything else about it. Duo says on his duo-r there is a rather large electrolytic cap in it's place.

I only realized this was a cap today as I didn't look at it to closely, dismissing it as something else. When I get back to my apartment tomorrow, I will try replacing it with a electrolytic cap with similar specs and see if it fixes or improves the audio issues on the duo I am repairing.

(http://pic.photobucket.com/bwe.png)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Duo_R on March 21, 2009, 01:51:58 PM
yup, I think we have discovered another cap. Is this the one that Nat mentioned a while back? I never assumed this was a cap until I saw my JP Duo with a large cap right in the same spot. Everything parts wise looks identical from JP Duo to US Duo so that part stuck out like a sore thumb. The US Duo has this Monolith rectangle looking thing that I guess IS a cap.

Here is a picture of the cap on the PC Engine Duo (big green cap):

(http://img27.imageshack.us/img27/1088/downsized0321091757m.html)

I will take another snap of the two Duo's that are side by side. I have been running / testing games with the covers off, I kinda feel like DJ Turbo......
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: nat on March 21, 2009, 02:07:25 PM
That's the BRAM battery.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Zeon on March 21, 2009, 02:31:49 PM
That's the BRAM battery.

Haha makes perfect sense, big cap for longer retention of save data. Don't know why I didn't think of that, well back to the drawing board, my next suspect is the M51131L which is a 2-Channel Electronic Volume Balance ic. Beyond that and the oki chips, and those small amps, i am stumped. My reasoning is suspecting the M51131L is that one of the audio caps that we typically replace in repairing duos, it dangerously close to the M51131L. When the cap leaks it's possible that electrolytic gets around the pins of the M51131L and shorts something out damaging it. Anyone know of a place where I can get a replacement?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: pceslayer on April 05, 2009, 07:31:20 AM
Does anybody know which caps are responsible for the operation of the laser?

I have an odd issue where my Duo won't reliably read tracks past a certain portion of the disc.

I'm not really sure its an issue with the caps at all, but figured i'd start here.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: nat on April 08, 2009, 02:57:42 PM
Your laser needs to be tuned. There are four or five pots on the Duo motherboard that control intensity, sensitivity, focus, etc. Calibration drifts over time.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: override on April 15, 2009, 03:56:06 PM
Was just wondering does it make a difference if the caps are "16 V" or "16VDC" ? Upon making an order on the net I noticed at checkout that some were VDC....

Thanks for the help

Also was wondering anyone that would recommend a site? I checked newark but they charge a $20 handling fee....I dont think I want to pay that...LOL $10 worth of caps turns out being damn near $40...

Hey NAT did you get my message?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: nat on April 15, 2009, 03:58:50 PM
No, they mean the exact same thing.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Zeon on April 15, 2009, 09:08:11 PM
Also was wondering anyone that would recommend a site? I checked newark but they charge a $20 handling fee....I dont think I want to pay that...LOL $10 worth of caps turns out being damn near $40...

Where do you live? I have ordered from newark in the past a few times and I have never been charged a $20 handling fee. If I was I would have ordered elsewhere!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: override on April 16, 2009, 02:27:00 AM
Where do you live? I have ordered from newark in the past a few times and I have never been charged a $20 handling fee. If I was I would have ordered elsewhere!

I live in Texas....I was pretty sure that newark was in the states so I dont understand why they want to charge me the handling fee either....Not sure but if I cant get it off I will find elsewhere...I have already looked around but the other sites I have found dont carry everything I need....I was very suprised to see that newark carried the .047 Micro Farad 5.5 V Polarized Cap! Its only $1.47 so not a bad deal for such an important cap (in my mind).
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Zeon on April 16, 2009, 08:20:45 AM
Where do you live? I have ordered from newark in the past a few times and I have never been charged a $20 handling fee. If I was I would have ordered elsewhere!

I live in Texas....I was pretty sure that newark was in the states so I dont understand why they want to charge me the handling fee either....Not sure but if I cant get it off I will find elsewhere...I have already looked around but the other sites I have found dont carry everything I need....I was very suprised to see that newark carried the .047 Micro Farad 5.5 V Polarized Cap! Its only $1.47 so not a bad deal for such an important cap (in my mind).

Really? So do I! Do you live in the DFW area by any chance? It's always cool to find out when a fellow member lives at least somewhat nearby.

Newark is in the states, and my last order (made last month) which consisted of mainly caps, some ics, a plastic enclosure, and other electronic miscellany did not have the $20 fee tacked on. How much does your order total to? They might only put it on really small orders as my last one was something like $47 before shipping and whatnot.

EDIT: Nevermind, I know why. You must be ordering one or more items that are labeled: "Farnell UK Direct Ship" which means that they don't have the item(s) available stateside, so they have to put in a special order direct from the UK. I generally avoid those items. See if they don't offer an equivalent that is in stock stateside. They should as they have a crap ton of caps in general.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: override on April 16, 2009, 11:43:37 AM

Really? So do I! Do you live in the DFW area by any chance? It's always cool to find out when a fellow member lives at least somewhat nearby.

Newark is in the states, and my last order (made last month) which consisted of mainly caps, some ics, a plastic enclosure, and other electronic miscellany did not have the $20 fee tacked on. How much does your order total to? They might only put it on really small orders as my last one was something like $47 before shipping and whatnot.

EDIT: Nevermind, I know why. You must be ordering one or more items that are labeled: "Farnell UK Direct Ship" which means that they don't have the item(s) available stateside, so they have to put in a special order direct from the UK. I generally avoid those items. See if they don't offer an equivalent that is in stock stateside. They should as they have a crap ton of caps in general.

I didnt think about that...Yeah I think I had a cap on there from like japan or something it was the only one that I didnt have to order 5 + just to get one! Cool I'll go change the order up a little! I need those caps cause my local dealer takes so long to get em and well he doesnt have much stock...

I live in Abilene, TX...Im about 2 hrs from you...I drive on the outskirts of DFW when I go to houston to get to danbury (my home town)!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: exile on May 12, 2009, 03:38:36 PM
Hello gents

I'm new to the boards and needed help with my american Turbo Duo. It loads CD fine but the sound it barely audible can anyone help me out here?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Charlie on May 13, 2009, 12:41:58 AM
So, you searched and didn't find "http://www.pcenginefx.com/forums/index.php?topic=960.0" or maybe
"http://www.pcenginefx.com/forums/index.php?topic=960.165"?

Hope this is not an omen!!


Charlie
 
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: blueraven on December 12, 2009, 09:05:04 PM
This is the PC Engine Duo I posted about in the Soundfix thread. Fortunately, replacing all of the caps (specifically the cluster around the heat-synchs) took care of the crackling and fades.

Redbook and Huey music running perfectly; clear graphics and sound. I re-flowed the solder on the AV port as well, and exclusively used NTK Hi-Temp Capacitors. The guys at the electronics store are going to start stocking them in bulk for me, so hopefully this won't be the first repair I report on.

(http://i430.photobucket.com/albums/qq21/Rookstower/Video%20Games/repairs/pceduo-fullcapreplacement.jpg)

Having the chart in front of me is really invaluable. Thanks again, RedGhost.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: chriscomputers on January 16, 2011, 03:59:26 PM
I have a question about some capacitors I just replaced on a Turbo Duo. I was having a CD player warm up issue. I replaced 4 of the caps below The CD player shown in my picture here circled in Red and it fixed my problem. I used 3 100UF 100V and then one 22UF 6.3V. I know the 3 100UF 100V will be fine but what about the 22UF at 6.3V? Think 6.3V is enough? I noticed on the old cap it read 22 6A 28H.


(http://img262.imageshack.us/img262/356/pcengineduototalcaprepl.html) (http://img262.imageshack.us/i/pcengineduototalcaprepl.jpg/)

Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on March 18, 2011, 08:53:38 PM
I have a question. I notice that on my duo there are quite a few capacitors that say 4.7 and then 6V afterwards. However at the beginning this article you say that 16V should be fine for all except the 3.3UF at 50V. So should I use 6V caps for those 4.7UF or should I use 16V?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Duo_R on March 19, 2011, 02:51:20 AM
16v is fine. You can go a little extra.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on March 19, 2011, 04:29:19 AM
Yeah you can always go higher voltage that what is called for but higher voltage caps are typically larger in size which can sometimes cause issues with physical space.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: grahf on March 19, 2011, 05:36:35 PM
I've got a spare IFU-30 (interface unit) coming in the mail, and I think I'll replace all the caps for the hell of it. It just feels good to know that everything is fresh inside.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on March 21, 2011, 02:50:47 AM
I've got a spare IFU-30 (interface unit) coming in the mail, and I think I'll replace all the caps for the hell of it. It just feels good to know that everything is fresh inside.

Good to see your back state-side grahf (lol... a while now, but still). Still making those mod boards? I still praise your work for the region and S-video mods.

Yep, I had to do the cap replacement myself before I sent my system off. It just happened to start having CD audio problems a little before you modded my system. I even had to replace the lens due to my CD-R phase, which I stay away from those now. I soon rather fire up the magic engine to play translated Ys 4 or Xak III which won't work on hardware anyways.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: grahf on March 21, 2011, 03:23:37 AM
Actually I'm still in Japan. I came across a white PCE in a junk pile, and here I am.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on March 25, 2011, 01:56:59 PM
I have one more cap replacement question. There are two caps on this board that seem impossible to get to from underneath even though they were originally soldered from underneath(circled in red). Would I be safe soldering new ones in from above? (http://img339.imageshack.us/img339/3568/pceduoswap003.html) (http://img339.imageshack.us/i/pceduoswap003.jpg/)

Uploaded with ImageShack.us (http://imageshack.us/)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on March 25, 2011, 02:17:03 PM
To do those two you need to bend up the BA chip on the bottom and temporariliy remove that pad under it.  Then you can access the solder points of those caps.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on March 25, 2011, 02:24:50 PM
Huh really? Is it okay to bend that up a little?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on March 25, 2011, 02:31:49 PM
Okay, I got it. Bent up just a bit to get the soldering iron tip under there. Thanks for the advice. I have replaced many caps on these before. Just not all of them at once for preemptive maintenance. Usually I just change the bad ones and call it at that.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on March 26, 2011, 02:49:21 AM
Huh really? Is it okay to bend that up a little?

I should have added "carefully" to that!  I have replacement BA chips if you manage to break one somehow
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Duo_R on March 26, 2011, 06:15:32 PM
I just replace those ones from the top, bending up the BA chip isnt necessary. 
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on March 31, 2011, 06:26:56 PM
One more capacitor question. Unfortunately some of the capacitors I ordered in showed up with NP on it and no - or + markings. Is a non-polarized capacitor bad to use?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on March 31, 2011, 06:36:22 PM
I thought there were specific applications for non polar caps so I want to say don't use them in plavmce of polarized caps.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on March 31, 2011, 06:37:31 PM
Yeah, that's what I was thinking. The ones that came this way were for the few 4.7UF caps on the board. I do have some spare 35V ones. Would that be way too high or should I just get 16V as recommended.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on April 05, 2011, 02:20:36 PM
You can always use higher voltage, they're just usually larger and can cause clearance issues in some applications.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 17, 2011, 11:28:24 AM
np (non polarized) caps are always safe as replacements for standard.
just never the other way round
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: goukisama on May 05, 2011, 09:03:34 PM
Thanks this guide helped me a lot on my pc engine duo. But the Cd drive still wont spin or run. Is there something i'm missing? Or am i going of topic?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on May 26, 2011, 07:30:09 PM
My first duo full cap replacement
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: chop5 on May 26, 2011, 08:38:09 PM
nice steve  :clap:   looks like factory repaired
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on May 27, 2011, 04:52:33 AM
Wow that's nice work!!   :clap:
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on May 27, 2011, 05:07:52 AM
thats the untouched duo you sent.
the laser appears good.
the cap related to laser had leaked everywhere
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on May 27, 2011, 06:10:20 AM
thats the untouched duo you sent.
the laser appears good.
the cap related to laser had leaked everywhere

I figured most of the problems were cap related on that unit.  It seems like more often than not, laser problems are caused by capacitor failure, not laser failure.  Keep that new laser I sent though.  You'll probably need it eventually.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on May 28, 2011, 04:21:20 PM
full cap replacement KIT for the DUO
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Harmik on June 14, 2011, 05:36:41 PM
Thank you to Red Ghost and everyone for the great info 
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: blueraven on June 29, 2011, 08:03:36 AM
Attached is a photo of a full silver cap replacement on a 1st gen Black PC Engine Duo with Hi-Temp NTK capacitors.

Hopefully this will go for another 20 years.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on January 27, 2012, 06:30:29 PM
to solve jail-bar issue on rgb modded system replace capacitor C961 10uf with 100uf tant or 220uf aluminum
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on January 30, 2012, 08:05:19 AM
to solve jail-bar issue on rgb modded system replace capacitor C961 10uf with 100uf tant or 220uf aluminum

Which cap is that exactly? Will this work for an S-video mod which is basically a RGB mod with S-video circuit after?

Also, I wonder if there is a way to get rid of some the RF like interference you see on some solid backgrounds like blue sky? I remember reading something about even getting rid of the HuCard chip tune humming after the music stops problem as well.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on January 30, 2012, 11:06:49 AM
its the cap thea the hu card sits above on the black unit
yes it clears up the noise on solid backgrounds, improving all outputs (including composite)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ApolloBoy on February 04, 2012, 07:10:10 PM
I'm in the midst of replacing the caps on a TurboDuo for a client of mine and it's actually much easier than I thought it would be. Tedious yes, but difficult not at all. I was almost expecting it to be like the TurboExpress where the solder pads will lift up if you do so much as look at them wrong, but the board is surprisingly sturdy.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on February 04, 2012, 07:29:28 PM
the black duo has a very solid board, the -R not so great
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: lastcallhall on February 06, 2012, 11:51:48 AM
the black duo has a very solid board, the -R not so great

I was actually looking at my Duo-R last night and decided I should probably replace all the caps as a precautionary measure. Well, that and my laser won't read much of anything other than audio CDs. I've tried adjusting the pot on the laser assembly itself, but not the V101-V105 pots on the board. However, my board looks different than the one shown in the original post - I'm guessing it has to do with it being a Japanese -R instead of an american Duo. In any event, are there any specific areas where I should use extra caution? Recapping is nothing new to me - I've done dozens of Genesis systems and rarely did I run into a problem, I was just concerned with your comment.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on February 06, 2012, 12:00:55 PM
the black duo has a very solid board, the -R not so great

I was actually looking at my Duo-R last night and decided I should probably replace all the caps as a precautionary measure. Well, that and my laser won't read much of anything other than audio CDs. I've tried adjusting the pot on the laser assembly itself, but not the V101-V105 pots on the board. However, my board looks different than the one shown in the original post - I'm guessing it has to do with it being a Japanese -R instead of an american Duo. In any event, are there any specific areas where I should use extra caution? Recapping is nothing new to me - I've done dozens of Genesis systems and rarely did I run into a problem, I was just concerned with your comment.

I havent seen the need to recap the R systems yet... not to say it wont start to have problems eventually though.  I'd try and adjust your laser first.  VR101-105 are your best bet,  the adjuster on the laser should be a last resort.  You may just need a new laser.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: lastcallhall on February 06, 2012, 12:23:59 PM
the black duo has a very solid board, the -R not so great

I was actually looking at my Duo-R last night and decided I should probably replace all the caps as a precautionary measure. Well, that and my laser won't read much of anything other than audio CDs. I've tried adjusting the pot on the laser assembly itself, but not the V101-V105 pots on the board. However, my board looks different than the one shown in the original post - I'm guessing it has to do with it being a Japanese -R instead of an american Duo. In any event, are there any specific areas where I should use extra caution? Recapping is nothing new to me - I've done dozens of Genesis systems and rarely did I run into a problem, I was just concerned with your comment.

I havent seen the need to recap the R systems yet... not to say it wont start to have problems eventually though.  I'd try and adjust your laser first.  VR101-105 are your best bet,  the adjuster on the laser should be a last resort.  You may just need a new laser.

Yeah, that was ordered today, as well. :)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: toofastforyahuh on April 15, 2012, 09:03:09 AM
I did a (nearly) total cap replacement on my TurboDuo and TurboExpress, with the help of a lab technician with expert soldering skills.
I missed the 3.3uF/50V cap and didn't touch the BRAM cap.
But otherwise I tried to make a part list for anyone who wants to do the job with correct size parts.
I posted it here in case anyone else finds it helpful.  There's a few empty fields (e.g. things I forgot or part numbers covered up by gunk).  Feel free to fill them in.

http://www.anthrofox.org/projects/turbo_caps.html
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 15, 2012, 10:33:07 AM
the 3.3 is a common failure part
nobody changes the BRAM cap
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 09, 2012, 03:22:30 AM
Hi everyone, just joined this forum because my Turbo Duo had extremely low audio.  I decided I'd replace the caps and ordered a whole batch of 105C caps off of Digikey.  I'm no stranger to soldering, but this is my first time replacing capacitors.  Could someone please explain to me how to know which end gets soldered where (+/-)?  Thanks.

I've already taken several closeup pictures of my Duo's motherboard before pulling the caps so I'll know exactly where everything was, and just pulled them all yesterday:

(http://i.imgur.com/r5lSxl.jpg) (http://i.imgur.com/r5lSx.jpg)


(http://i.imgur.com/3bfnhl.jpg) (http://i.imgur.com/3bfnh.jpg)

The red circled areas had leaked all over and it smelled like bad fish when I took some of the caps off in those areas.  Some of the electrolyte fluid had corroded a couple of the solder pads, but I was able to clean some of it and salvage the pads (thank goodness)!  The parts should be here around Tuesday and hopefully I can start then.  So ya, if someone could help me on the +/- guidance for the caps, I'd appreciate it, thanks!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on June 09, 2012, 03:33:17 AM
On the cap replacement chart at the beginning of this thread, the black side is the negative side.  Typically on the board they're marked with either white around the hole (for through mount caps) or the flat squared side of the SMT shape printed on the board.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 09, 2012, 04:10:17 AM
Ok thanks, and I'm correct in assuming that the longer lead on the capacitors is negative?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on June 09, 2012, 04:14:56 AM
Ok thanks, and I'm correct in assuming that the longer lead on the capacitors is negative?

The sides of the capacitors housing should be marked with a line or bar indicating which side is negative.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gilao on June 09, 2012, 07:49:46 PM
I have a Turbo Duo and was without sound, the sound was very low even changed all the capacitors, now the Hu Card games have sound normal, but the games on CD still has very low sound, have to increase the TV volume at most and is still down, anyone know what can be ? Thank´s.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 14, 2012, 10:25:03 AM
Quick question...I don't see the location of the 3.3uF 50V capacitor anywhere on the diagram.  Where does that one go?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on June 14, 2012, 12:29:05 PM
3.3 is under the cd drive wires
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 14, 2012, 02:49:59 PM
Got it, just replaced all my caps and sound is working 100% on hucards and cd games again:

(http://i.imgur.com/lfBKSl.jpg)

Now my CD drive doesn't spin up though.  The laser is still powered and tries to read the disc, but it doesn't spin.  I'm hoping I just forgot to plug something in but what could that be?  It worked perfectly fine before I did this.

EDIT:

Nevermind, I had the CD wires in the way, also forgot the disc won't spin unless the laser detects the disc first.  Works great now!  Another Turbo Duo saved from the capacitor leak issue!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: HercTNT on June 14, 2012, 07:39:39 PM
Stories like this bring tears to my eyes. Another success story from the Pcenginefx STTF "Save The Turbo Foundation".
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Necromancer on June 15, 2012, 04:39:04 AM
Another Duo saved to OBEY another day!  Well done, ConHuevos.  8)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 16, 2012, 09:55:17 PM
Ok, today I noticed something that isn't normal.  I'm only getting audio from one channel.  My white audio plug has no audio coming out of the duo, via hucard or CD-ROM.

Any idea what can cause this? :(

I hope it's something simple I overlooked.  Worst case scenario...how much would it cost to have this repaired by one of the board members? :(
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on June 16, 2012, 11:47:20 PM
could be your AV cable
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 17, 2012, 07:51:53 AM
could be your AV cable


As much as I would like it to be, I don't think it is =/.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on June 17, 2012, 08:08:03 AM
If its not your AV cables, then its probably a corroded via or trace caused by the leaked cap fluid.  Did you clean the board really well before you put the new caps in?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 17, 2012, 09:03:36 AM
I tried my best with alcohol, the back of the board is covered in yellowish liquid I tried to clean off.  2 of my solder pads were somewhat messed up but I managed to salvage them.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on June 17, 2012, 09:54:09 AM
On this duo, I had no sound even after a cap swap.  Look at the black crud around one of the via holes.  A through cleaning then testing of continuity and repair of some of the vias was necessary.

(http://i905.photobucket.com/albums/ac253/bmcdanold/Repair/DuoSound2.jpg)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 17, 2012, 11:23:18 AM
Via?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on June 17, 2012, 11:30:06 AM
Vias are the little holes in the board that make connections from one side of the board to the other.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on June 17, 2012, 11:40:28 AM
the via's are often bare copper plated, making them easily corroded.
a wire strand through the hole and soldered up fixes them
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on June 17, 2012, 12:16:21 PM
Blue, how much would it cost to ship to you and fix the sound?  This is my spare duo, but playing order of the griffon with only 1 sound channel annoys me so much :(.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on June 30, 2012, 07:52:14 AM
Randomly found this today, so for possible useful reference:

"PC Engine Duo/Turbo Duo Capacitor Replacement Set"

Cost: $9.99

http://gamedoctorhk.com/index.php?main_page=product_info&products_id=1143

(http://gamedoctorhk.com/images/PCN/Pc-2072.jpg)

They've got NEC parts/games, laser units for DUO-R/DUO-RX, etc. Anyway, might be useful for someone though I think if I ever do this for my Duo when it breaks, I'm gonna try to buy tantalums this time instead (unlike my TE).
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ConHuevos on July 03, 2012, 08:35:27 PM
Ya, I saw that when I went to replace mine.  But then I noticed they are from China, and really didn't wanna trust the quality of capacitors they're getting.  Besides, for $2 more I got all hi temp caps from digikey so I had piece of mind and knew they were from a good brand, not cheap Chinese junk (not saying that's what it is, but it may be).

Shout outs to thesteve for fixing my sound issue, fixed it the day it arrived at his door.  Thanks!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on July 30, 2012, 10:59:34 PM
Well, stayed up all damn night trying to fix the right (red) sound channel and I still get no sound at all. It was actually extremely low volume before I did the entire cap replacement. I tested the AV out on the side and the headphone jack. I am seriously out of ideas.

I also managed to lift a few traces, but was able to get a connection through the Vias (copper holes). I also have to redo the region mod connection, as it is a complete bitch to get to the lower cut pins and solder wires off the HuCard slot. Sighhhh...

Anybody know the full trace route for the right sound channel from beginning to end?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on July 31, 2012, 06:54:16 PM
 :x Well, spent a good 12 hours today trying to fix my Duo and this shit is hopeless. When I unhook the region mod entirely the system boots to CD start menu but the disc drive is just flat out dead. When I wire-up the region mod the system is stuck on a light blue screen no matter what.

I. am. screwed!!!

Anybody want to have a go with it? I am considering sending it off to get fixed. If it doesn't come back to life, then I guess I can scrap it. I definitely would like to keep the grahf made region mod board in the long run. The newer and easier S-video mod will more than suffice now that the knowledge is out.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on July 31, 2012, 09:49:55 PM
the blue screen means you have a wire crossed on the mod.
not sure why your cd drive is dead
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Charlie on August 01, 2012, 12:45:04 PM
=>>Anybody know the full trace route for the right sound channel from beginning to end?<==

What, abbreviated schematics and technical descriptions aren't enough?  We have a lot of these here, about many of these consoles.
Try a seach for "Duo" and "schematic"....I'm pretty sure that there are numerous threads here about this, and many of them lead to other threads.  There may even be one actually related to the DUO and it's audio.

Good luck.

Charlie
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on August 01, 2012, 12:49:15 PM
=>>Anybody know the full trace route for the right sound channel from beginning to end?<==

What, abbreviated schematics and technical descriptions aren't enough?  We have a lot of these here, about many of these consoles.
Try a seach for "Duo" and "schematic"....I'm pretty sure that there are numerous threads here about this, and many of them lead to other threads.  There may even be one actually related to the DUO and it's audio.

Good luck.

Charlie


I was just looking at that schematic the other day...  its there SNK, just search for it.  I'm pretty sure Charlie posted it.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on August 01, 2012, 02:45:45 PM
remember its not a full schematic, but it should get you in the ball park.
as a side note check the voltages on the caps by the EVC chip (SIP behind the heatsinks)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on August 02, 2012, 10:22:17 AM
I wondering if the 470uf just above the heatsinks is the culprit. It is possible I slightly overheated it with the solder iron. It was a big pain to get out due to the wires being bent when originally installed. My multimeter display shows random garbage unless I mash the screen in a little, so this will be fun.

Any tips on soldering to the hucard slot pins? I feel like a I am playing a game of operation that is 10x as hard. I am roughly intermediate to advance at soldering over the years, but not quite the expert. Maybe if I were to take some sort sniper tranquilizer, lol.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on August 02, 2012, 10:50:24 AM
rest your wrist on something for stability.
the 47uf SMD cap behind the heatsink (right side) is where i would start with a meter, as its the CDA volume control voltage
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on August 02, 2012, 12:25:34 PM
Having another go at it tonight. Wish me luck, lol.

Volume level is now secondary, as getting the machine to play games again is my concern for now. I know it works after my previous test with region mod disconnected. I just have to check my wiring connections on the HuCard slot. I know I have the right pattern. It is a tight and small in that area, so it is easy to connect pins next to each other by accident. You couldn't pay me to mess with that section.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on August 02, 2012, 12:50:12 PM
remember, if your meter has a ---|>|-- function, you can test the mod with it.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: fraggore on August 26, 2012, 02:44:51 AM
Thanks for the guide very usefull.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: turbokon on October 06, 2012, 05:35:24 AM
I'm working on cap replacement on a pce duo I just got from game of Japan. I noticed that there is a place for a cap that's not on the chart. I can't remember if I removed the cap from that spot or not but from the looks of residue, I assume there was. Anybody knows what value cap this might be, next to that Sanyo chip?
(http://pic.photobucket.com/bwe.png)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on October 06, 2012, 09:23:06 AM
never installed
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: turbokon on October 06, 2012, 09:57:17 AM
Cool, thanks.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on October 10, 2012, 12:04:03 PM
jailbar filter caps (someone asked)
(http://pcengine.freeforums.org/download/file.php?id=72)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on October 13, 2012, 08:12:43 AM
Wow, you really are a dangerous "cowboy," aren't ya, steve? ;) What kind of experimentation was necessary to figure this kind of thing out I wonder ?? Grounding certain pins of the video chip with caps, wouldn't have thought of that, ever... Does anyone have a good picture of this "jailbar" problem BTW ? Just curious. I don't quite know what it is exactly.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: cosmos99 on October 26, 2012, 09:49:20 AM
Hi everyone , here's a listing i've made at Digikey , it includes all caps ,same size ,shape ,voltage and capacity.

CMS

10 uf 16 v x 6 565-2442-1-ND (dia 4 surf mont 4,3 x 4,3)
22 uf 16 v x 19 565-2443-1-ND (dia 5 surf mont 5,3 x 5,3)
100 uf 6v x 10 PCE3852CT-ND (dia 6,30 surf mont 6,6 x 6,6)
4,7 uf 35 v x 4 PCE4687CT-ND (dia 4 surf mont 4,3 x 4,3)
22 uf 6 v x 19 PCE4647CT-ND (dia 4 surf mont 4,3 x 4,3)
47 uf 16 v x 4 PCE3889CT-ND (dia 6,30 surf mont 6,6 x 6,6)

ON HOLE

1000 uf 16 v x 1 P5142-ND
470 uf 16 v x 3 493-1523-ND
100 uf 10 v x 1 P5123-ND
330 uf 16 v x 3 399-6579-ND
100 uf 16 v x 2 399-6648-1-ND
220 uf 16 v x 1 493-1783-ND
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on October 26, 2012, 04:32:46 PM
Finally sent my Duo off to thesteve. I got fed up with the cap replacement errors adding up.

Also, those pins for the region mod are quite a pain to get line up with the wires along with the small space. I even slightly touched the plastic on the HuCard slot with the iron. I was getting a little anxious I guess.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: JohnnyPhantom on November 14, 2012, 04:41:45 AM
This is like a Where's Waldo game for me :P as hard as I look I cannot seem to find the 1X 3.3uf 50V cap on the photo, can anyone tell me where it may be?
thanks!!



Never mind found a previous post that says where it is, under the CD drive cables ^-^
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on December 05, 2012, 03:08:13 AM
Forgot to mention... I got my Turbo Duo back from thesteve Monday. The system is running better than ever. Total cap replacement, rewired the region mod since I goofed it, took out the CXA 2075 and did the newer S-video mod with the jailbar fix, tweaked the laser to run even better and added some RCA stereo jacks to the back for me. The video looks even sharper, minimal jailbars, and the colors and brightness seem to be more accurate to the original look.

In 2 days I beat Gate of Thunder, Lords of Thunder, Double Dragon 2, Ninja Spirit, Cadash, and almost beat Super Star Soldier again. I am playing through Ys 1+2 and almost finished beating Ys 1. Seems to be running for the Gold.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: MotherGunner on December 05, 2012, 10:41:12 AM
So I have an S-Video Duo-R and I believe I have the jailbar issue.  Are we talking about the faint vertical lines on the screen?  If so, does The Steve have a fix for this? 

I also have the same issues on a couple of NES's I am trying to get repaired.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on December 05, 2012, 11:22:58 AM
So I have an S-Video Duo-R and I believe I have the jailbar issue.  Are we talking about the faint vertical lines on the screen?  If so, does The Steve have a fix for this?  

I also have the same issues on a couple of NES's I am trying to get repaired.
post 127..............(look up)

duo-r same pins, top of board
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SNKNostalgia on December 05, 2012, 12:52:17 PM
So I have an S-Video Duo-R and I believe I have the jailbar issue.  Are we talking about the faint vertical lines on the screen?  If so, does The Steve have a fix for this? 

I also have the same issues on a couple of NES's I am trying to get repaired.


Here's a guide to AV mod a Toploader correctly.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: MotherGunner on December 05, 2012, 01:52:46 PM
Oh so it's not the vertical lines through s-video issue but referring to the PCB.  Does anyone know how to makes the vertical lines go away?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on December 05, 2012, 01:54:39 PM
yes it is the vertical lines
add 2 caps as pictured
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: MotherGunner on December 05, 2012, 02:07:35 PM
Thanks Steve. PM incoming. :-)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on December 06, 2012, 01:26:59 AM
Urm, stevie, might you be willing to grant the people that are interested in eliminating the jailbar issue the knowledge of the capacitance value of those surface mount caps that you added ? ;) Or am I missing something here ? I didn't see where that info is at... Even if you don't have this problem, is it worthwhile to do it anyway ? Does this problem occur with S-Video and YPbPr output ?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on December 06, 2012, 03:58:37 AM
i used 22uf caps in the pic.
depending on your mod, you may need more capacitance.
it effects all outputs to differing degrees.
S-Vid (my way) doesnt suffer much.
anything from the RGB pins does
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: DarkKobold on December 11, 2012, 06:25:10 AM
Has anyone ever replaced the surface mount caps with new surface mount caps? I actually have a stock of the proper surface mount caps, but I imagine it would take a skilled tech to do the replacements.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on December 11, 2012, 07:05:58 AM
what do you mean?
we replace the aluminum surface mount caps regularly. (i use surface mount replacements)
the ceramic and tantalum rarely if ever need it.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: DarkKobold on December 11, 2012, 02:46:54 PM
what do you mean?
we replace the aluminum surface mount caps regularly. (i use surface mount replacements)
the ceramic and tantalum rarely if ever need it.


Most people do like this one:

http://i1125.photobucket.com/albums/l594/superkon316/E5F7ADB3-2ACE-4C39-9749-958A676769F5-618-000001093B5D805C.jpg (http://pic.photobucket.com/bwe.png)

They use radial through-hole capacitors to replace surfacemount caps. 
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on December 11, 2012, 06:09:28 PM
(http://www.pcenginefx.com/forums/index.php?action=dlattach;topic=10167.0;attach=763;image)
using ceramic and tantalum SMD for replacements
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: King_Vidiot on January 04, 2013, 05:28:06 PM
Where's the best place to buy the caps needed for this?  I sent my turbo duo to a board member a few years ago but when I got it back it was still dropping the background music.  I assume they got lazy and didnt replace all the caps.  

Also can I just use regular caps? Or is sticking with surface mount caps better in the long run?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on January 04, 2013, 06:47:44 PM
The regular aluminum caps are cheaper and you're better off with those. The surface mount aluminum ones are for tight spaces, but that isn't a problem when it comes to Duos. Neither is it much of one with the Express if you don't bother to put the RF shield plate back on. If you got money to spend, then you could go ceramic/tantalum like steve says, but it'd be way too much money for a Duo... I bought a big 900 pack cap kit for $25 bucks from a Chinese seller on eBay, and that's gonna have to do. Search eBay for capacitor kits and you'll find good deals on regular ones.

The seller has more: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190771132156

It arrived in 9-10 days. I've been impressed with all my purchases from China, both in price and the decent shipping time given the distance.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: ApolloBoy on January 04, 2013, 08:10:08 PM
I don't know if I'd recommend cheap Chinese caps though, those usually don't last very long in my experience. For almost all of my recap jobs I use Nichicon, Nippon Chemi-Con and Panasonic caps which are excellent quality and should last for decades.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on January 04, 2013, 08:27:30 PM
Who do you buy from ?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on January 06, 2013, 04:09:38 PM
I typically use Panasonic and buy from Mouser.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: kato on January 07, 2013, 01:24:42 AM
Somebody linked this shop (http://gamedoctorhk.com/index.php?main_page=product_info&products_id=1143) in this thread.
Now I am little confused. Should I use 4.7µF with 16V or with 50V?

And I can't find anywhere (within Europe) Panasonic caps with 22µF/16V with a lifetime of 5000h-10000h, only 22µF/25V with 1000h-5000h lifetime or 22µF/50V with a lifetime of 5000h-10000h.
I want them to last as long as possible. Any recommendations?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on January 07, 2013, 03:09:37 PM
Somebody linked this shop (http://gamedoctorhk.com/index.php?main_page=product_info&products_id=1143) in this thread.
Now I am little confused. Should I use 4.7µF with 16V or with 50V?


That has exactly what you need in one package, one price, but nobody could vouch for the quality. You'll likely need to buy at least two cap kits to get all the values elsewhere.

A small 4.7µF capacitor is likely gonna have a high breakdown voltage of 50V, but anyhow, 16V would still be safe. The Turbo Duo operates at 5V max past the voltage regulator where 10V comes in from the unregulated power supply (so it's probably like ~12.5V)... So, since the motherboard operates at 5V, 16V max caps are perfectly safe and way above that.

When you start getting lower than 10µF to 5µF to 1µF and below (1000pF) as far as capacitance goes, you start getting into the ranges that ceramic capacitors support and they can handle 50V to 250V, while still being small, etc. So, that's why, even though it's aluminum, it can handle 50V max... At 22µF and above, something like that, the the breakdown voltage that the cap can handle goes down, but for more money and at the expense of a bigger size, you can still get them with higher rated breakdown voltages, etc.

Quote
And I can't find anywhere (within Europe) Panasonic caps with 22µF/16V with a lifetime of 5000h-10000h, only 22µF/25V with 1000h-5000h lifetime or 22µF/50V with a lifetime of 5000h-10000h.
I want them to last as long as possible. Any recommendations?


The higher the max breakdown voltage is, the more expensive and bigger the capacitor will be.  As long as it says 22µF, you can use it just fine! So get the expensive 22µF/50V ones if you wanna spend the money and want a high lifetime rating.

Basically, the rule for replacing is: make sure the capacitance value matches exactly, and that the voltage rating is at least twice what the circuit operates at. And simply know that the higher the max breakdown voltage is, the more expensive and bigger that the capacitor will be, as I said, but that it'll still work fine and likely just last longer...
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: kato on January 09, 2013, 04:34:01 AM
Ok, thanks!

Does it matter whether I use caps with a maximum temperature capacity of 85°C or 105°C?
It's hard to find all needed caps made by Panasonic. It's easier for me to get caps made by Yageo. Are these any good or are these just cheap Chinese caps?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on January 09, 2013, 04:47:59 AM
If youd like, ill put together a cap kit for you.  Shoot me a pm if youre interested.  All Panasonics.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on January 10, 2013, 05:42:48 AM
Basically, the rule for replacing is: make sure the capacitance value matches exactly, and that the voltage rating is at least twice what the circuit operates at. And simply know that the higher the max breakdown voltage is, the more expensive and bigger that the capacitor will be, as I said, but that it'll still work fine and likely just last longer...
[/quote]

just wanted to add
the life rating of the cap is when operated at its specified voltage/ripple
operating a cap below its ratings will extend its life greatly.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: drakewolfe on January 21, 2013, 08:46:14 PM
I found this website http://www.anthrofox.org/projects/turbo_caps.html that seems to go into detail about the cap replacement.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on January 23, 2013, 05:25:22 PM
Figured I'd add this in. This youtuber bought a kit from console5 and got his Turbo Duo working with it.


http://console5.com/store/kits/game-console-cap-kits/game-console-cap-kits-nec/nec-turboduo-cap-kit.html (more $$$ than the HK link though)

The thing about these exact kits is that they're not cost-effective but if you think you'll only ever do something like this once, then they work. For 10 bucks from these Chinese sellers, you can find kits that have 200 pieces total, 20 of each, etc., and after doing a full cap replacement, you'll have plenty of caps left to spare for other possible projects. But you'll likely need to get at least two of these kits in order to get all of the needed values and amounts in the Turbo Duo's case. Anyhow, I'd still say stick to eBay hunting for cap kits there.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on February 26, 2013, 02:09:52 PM
jailbar filter caps (someone asked)
(http://pcengine.freeforums.org/download/file.php?id=72)




I can say this works quite good!  Keith Courage always shows jailbars on the solid blue backgrounds.  Here's a duo RX after installing some caps like steve showed.

(http://i905.photobucket.com/albums/ac253/bmcdanold/KeithRGB_zpsd849a9c1.jpg)

Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on February 26, 2013, 02:30:03 PM
Huh, I've never come across a system that displayed jailbars before. Does it happen with just the stadard composite out or does it happen more when using S-Video or Component?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: BlueBMW on February 27, 2013, 12:04:20 AM
Mostly on RGB modded systems.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on February 27, 2013, 02:52:33 AM
Huh, I've never come across a system that displayed jailbars before. Does it happen with just the stadard composite out or does it happen more when using S-Video or Component?

No, like Blue said, it's a problem that occurs with a RGB connection from what I have heard.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on March 31, 2013, 06:26:24 PM
No, the jailbar problem is everywhere (RGB, composite etc) and on all PCEngines, you just need to be observative. Its most obvious on solid light colour backgrounds, specificly during horizontal movement and more on LCD tvs than CRTs.
Its more obvious on RGB because RGB gives the best, crispier picture possible but I've noticed the jailbars on all my TG consoles even on composite. Composite is just blurrier so it makes the jailbars less obvious.
From the PCEs I own (and I own many), by far the most intense jailbars are on the Core II.

Does the two tantalum caps shown in the picture above completely solves the jailbar issue or does it make it "lighter"?

I tried another jailbar fix sometime ago that involved tantalum caps (dont remember from whom it was) but not on the legs of the chip. Did nothing for me...
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on March 31, 2013, 07:00:20 PM
the effectiveness of the caps depends on how close to the chip you can get then and the ESR of the caps.
also RGB mods will often have secondary jailbars caused by the amp/chip/cable/tv grounds not tied at the same point (look up ground loop)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on March 31, 2013, 07:18:58 PM
Yes its understandable, lets say they are as close to the chip as they can get, like directly soldered on the chip's legs as shown in the picture. Are the jailbars noticeable or completely gone?

Are these caps shown in the picture ceramic or electrolytic? Are they tantalum? I thought tantalum were electrolytic...
Title: Re: REPAIR GUIDE - Simple Jailbar Fix
Post by: NightWolve on April 01, 2013, 12:04:58 AM
To help out, I had made this for the Component thread from steve's photo:

(http://www.pcenginefx.com/forums/index.php?action=dlattach;topic=13231.0;attach=1391;image)

They're polarized tantalums. Fortunately, they're both easy to do. Pin 41 is at the corner of the chip, so you have less of a chance to bridge the pin next to it as opposed to if you had to solder to a pin that has a pin to the left and right of it. As for pin 43, at least in the case where it's on the bottom of a US Duo, you can scrape off the film from the trace or better yet at the via further away from the pin, solder there AND your ground is right there also, so less risky overall, etc.

I tried another jailbar fix sometime ago that involved tantalum caps (dont remember from whom it was) but not on the legs of the chip. Did nothing for me...


You didn't have steve on the case then. ;) As to how well this works, the last comment from someone that tried it was "vastly improved." (http://www.pcenginefx.com/forums/index.php?topic=13231.msg288797#msg288797) I'd say that's another satisfied customer!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 01, 2013, 04:47:01 AM
Ahhh thanks, that answers my question... so I need two 22uF 16v polarized tantalum for each console.

Actually I tried the "to solve jail-bar issue on rgb modded system replace capacitor C961 10uf with 100uf tant or 220uf aluminum" mod, which was also steve's but did nothing for me. I hope that one works :)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 01, 2013, 05:23:06 AM
this one works on the same concept, except it eliminates the variances in the boards by going direct to the chip and adds a cap to the 5v rail
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 01, 2013, 06:03:27 AM
Well I know some people said they saw a difference by doing the C961 cap mod, but I didn't (on my black PCEngine DUO R).
Already ordered some 22uF 16V polarized tantalums and I'll try the other mod, hope this one will make a difference for me :)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 01, 2013, 08:28:44 AM
its possible your getting jailbars from cabling as well
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 01, 2013, 05:09:16 PM
From cabling you mean the RGB cabling? Well I thought that too but I could see jailbars on composite even without the RGB amplifier installed.
I see jailbars even on simple unmodified TG-16 on composite taken from the expansion slot so I doubt its my cabling.... if it was I would be able to see changes at the jailbars just by moving cables around which I don't.

And anyway, nobody reported a significant improvement by just doing the C961 mod so why should it be my cabling....
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 01, 2013, 06:42:57 PM
when i did an lm1881 on the far end of a cable, it caused them as well.
it was solved by adding a cap to the lm1881 power pin
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 01, 2013, 09:45:48 PM
What capacitor value did you use?
Using the lm1881 on the far end of the cable.... doesn't that make the cable an "antenna" for introducng interference in the power line?

I use the amplifier with the 4 transistors (R G B and Sync amplification ) that was published for the PCEngine ages ago, but always inside the console. Cables are as short as possible (considering the lengths needed to pick the signals), and are taken from an IDE stripe cable.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 02, 2013, 06:06:33 AM
i put a 470uf across the lm1881
the cap was overkill
the reason i did it like i did was, to make a scart to RGBS adapter for my display
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 10, 2013, 11:16:29 PM
The PCEngine DUO (black) must have the worst jailbar problem of them all.

I did mine with two 22uF 16V tantalum caps, here's a picture...

(http://img442.imageshack.us/img442/4126/imag0053rx.html) (http://imageshack.us/photo/my-images/442/imag0053rx.jpg/)

There is an improvement (LCD tv), I would call it an average and not vast one though... jailbars are kind of dispersed but still there.
Or maybe I'm just being anal about them (like looking for jailbars at the lcd screen from different angles) :wink:

I wish there was a solution that completely eradicates the deam jail bars, like there is one for the famicom system. It involves shielding the chip with copper foil among other things... don't know if that would help the PCE though

Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 11, 2013, 06:45:26 AM
where is your amp ground?
your RGB amp needs to ground by that chip
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 11, 2013, 07:07:29 AM
The amp is on the other side of the board, here's a picture. I'm getting ground from the video out socket.

(http://img15.imageshack.us/img15/579/dscn0045rb.html) (http://imageshack.us/photo/my-images/15/dscn0045rb.jpg/)

Where exactly do you mean I have to get ground for the amp? Like from one of the tantalum capacitor's negative pole to prevent ground loop?

I take +5V from the socket too... do you think I should be taking it from another spot?

What happens with other PCEs like the Core II for example.... I use the same amp but I took all signals and ground and 5V from the expansion port... Is that ok or should I get ground right next to the chip again?

Thanx for your help.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 11, 2013, 07:40:31 AM
http://img442.imageshack.us/img442/4126/imag0053rx.jpg (http://img442.imageshack.us/img442/4126/imag0053rx.html)

A little big those two, but you managed to pull it off. The seller typically provides the dimensions of a cap so you can better pick ones that'll fit BTW.

Where exactly do you mean I have to get ground for the amp? Like from one of the tantalum capacitor's negative pole to prevent ground loop?


Yeah, that sounds like what he's saying. There should be a 5th wire close to that chip and where you soldered the negative end of the caps is ground, so that'd be one place. I would guess identifying an actual pin that IS grounded would be even better according to what he's saying. As for a +5V source, tapping it right from the regulator is the best if you can manage it. Tapping it elsewhere means more resistance having traveled around via traces, so it's less clean. This seems to matter with region mods or something and those older flashcarts not working right unless you tap the +5V needed power from the regulator. Anyway, I don't think it matters much here powering a little amplifier, so I'd just try his ground suggestion.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 11, 2013, 07:58:44 AM
Yeah I think thats the case too :)

Well since these caps are tantalum 22uF 16V, Ι dont think they come in smaller sizes for this capacitance at least. Ceramic may be smaller though. Compare with the tantalums (non SMD) steve has in his picture http://imageshack.us/a/img221/3182/20130314222631.jpg (http://imagizer.imageshack.us/a/img221/3182/20130314222631.html) ... they are just about the same size. The weird thing is that I don't see a ground cable close to the chip, unless he's not using an amp.

ps
The video socket's 5V is pretty close to the regulator so I think its OK, unless steve suggests otherwise.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 11, 2013, 08:12:55 AM
http://gamesx.com/wiki/doku.php?id=hu6260_netlist

OK, going by that, pin 39 is GND (next to pin 40/Luma), pin 48 is GND (in between Red and Green), etc. There are several.

Use a DMM and do a continuity test to make sure with a known ground point and I guess I would solder directly on one of those pins.

The video socket's 5V is pretty close to the regulator so I think its OK, unless steve suggests otherwise.


Well, that's where a +5V source is normally taken on the top of the PCB and you've had reports of the problems with this region mod/flashcart issue which are solved by tapping the output pin of one of the regulators, etc. But yeah, I guess it's a matter of "juice" and this is a little amplifier, so probably not necessary to go that far.

EDIT: OK, here's some context, a thread about the +5V regulator/switchless region mod issue (http://www.pcenginefx.com/forums/index.php?topic=12538.0). Just so you know what I was referring to. People report they fixed some crashes/issues with flashcarts and that region mod or whatever. Drakon says he always taps +5V from the regulator, etc. Your voltage will likely read higher, ~5.32 V or so whereas the at the AV out, I was getting like 5.02 V, etc.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 11, 2013, 08:51:50 AM
Yes I understand the issue about 5V, but its an analog amp with low power consumption. Region mods are complicated and probably more power consuming. Anyway, its hooked on the video socket's 5V and if you exclude the jailbar issue, the picture is perfect otherwise. If unclean power supply can cause jailbars then I'll go for the regulator but I doubt it can...

OK I'll try it tomorrow and see if the jailbars go away even more.

But what about PCEngines that the signals aren't taken straight from the chip but from the expansion board... is the chip still the best point to get ground from or the GRND dron the expansion port is OK?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 11, 2013, 08:56:15 AM
He said the RGB amp needs to ground as close as possible to the 6260 chip (going by what he's saying), so a grounded pin on the chip would be the best. Grounding via the expansion port would be worse, further away from the chip.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 11, 2013, 08:59:03 AM
So taking the signals and power from the expansion port is OK as long as you're getting ground from 6260's pin or close right? Or geting the other signals straight from the chip too is mandatory to avoid jailbars? I would love steve's confirmation on that one too  :D
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 11, 2013, 09:07:29 AM
Well, people have been doing it that way, so yeah, I guess. But if you gotta ground at the chip to really solve this jailbar issue as he is saying anyway, you might as well tap the RGB+S directly with new/good wires as just by basic physics you'll get the strongest signal sources there pre-amplification. At the expansion port, the signals have traveled from the chip to the traces to those pins, etc. hence resistance. Your new wires directly from the chip to the amp will likely subtract a little resistance.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 11, 2013, 09:37:09 AM
the signals should be fine
the ground traces are sig and power
when power flows thru a ground it causes noise
the longer the wire/trace the more noise it causes
the caps clamp the noise from point to point
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 11, 2013, 10:35:05 AM
How do you determine the capacitance value for these caps to "clamp" the noise ?? Would an official method be to connect an oscilloscope and see the noise, then add values from 10 uF and up and observe what value best helps "clamp" off the noise ?? Something like that ??
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 11, 2013, 05:22:13 PM
consider its not so much correct value, as sufficient value
the best way to test it is be visual effect, as the noise is to small to see on a scope (normally)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 11, 2013, 05:27:01 PM
Thanks Steve.

So taking the signals and +5V from the expansion port's pins isn't a problem I guess so I'll only change the ground to all six of my modded PCEngines (and install the tantalums ofcourse) :)

Do you think that connecting the ground wire to the 6260 chip's ground pin (pin 55 or 56 according to this guy ) is better than connecting it just next to it (onboard)? Well ofcourse it sounds better but will it make any difference?

Actually my DUO R (white) must be personally modded by the guy in the video because it is exactly the same (same amp, same connections and all). It gives very good picture with very faint jailbars but he's using composite instead of sync.
He's getting 5V from the 7805 regulator.... I will do the same like NightWolve suggested.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 11, 2013, 07:21:23 PM
Yeah, pin 55 and 56 are also ground according to the list I linked you earlier (http://gamesx.com/wiki/doku.php?id=hu6260_netlist) and what he used in the video. Whether he knew it or not as far as the benefits, he did a steve-approved modding job. ;) I would probably use pin 48 since it's right in between Red and Green, but yeah, any of the pins listed as GND will work. He probably used 55 cause it'd be easier to solder, less chance of bridging since you'd have Red, Gnd, and Green soldered next to each other. I think I could do it with my equipment, but maybe not.

Anyhow, very cool modding video by this guy! That's close to what I would like to have been making already...

P.S.

Why do you have 6 PC Engines ?? ;)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 11, 2013, 07:48:04 PM
Why do I have 6? (hehehehe..... good question)... 2xTG16 (plus 1x SuperCD Rom), 1xCore II, 1xPCE DUO, 1xPCE DUO R, 1x Super Grafx, all boxed. I'm still missing some :) Huuuuge PCE fan  :lol:

I think pins 55 and 56 is the ideal place for ground exactly for the reason you mentioned (easier to solder) plus its good for the ground wire to be thicker (same for the 5V wire too). So you could just solder it on both pins...

edit...
I did the connections of both ground (to pins 55-56) and +5V to the right leg of the 7805 regulator.
Didn't notice any change compared to the previous state which had the two caps installed that indeed made a whole lot of difference.
If there was indeed a ground loop, it wasn't causing something noticable (at my DUO system at least).

To put it all in a nutshell, the caps do make a big difference. My DUO had the worse jailbars (very obvious and irritating) and now its the best of all my PCE systems. The jailbars don't go away completely, you'll spot them if you're anal about it but you must be looking for them to see them.

I even compared the DUO R which the guy on the video must have modded and the jailbars are more intense compared to the DUO with the tantalum caps.

I will install the caps on all the rest of my systems.... I won't switch the 5V source to the regulator and I'm not so sure changing the ground will add anything to the equation....

(http://img43.imageshack.us/img43/3247/imag0054it.html) (http://imageshack.us/photo/my-images/43/imag0054it.jpg/)

(http://img11.imageshack.us/img11/7223/imag0056la.html) (http://imageshack.us/photo/my-images/11/imag0056la.jpg/)

(http://img17.imageshack.us/img17/8670/imag0060v.html) (http://imageshack.us/photo/my-images/17/imag0060v.jpg/)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 12, 2013, 09:47:35 AM
That first photo looks great, gt! Bravo, ya modding-maga! ;) I think I like that you can bridge pins 55+56 and use a thicker gauge wire, so I changed my mind, that's how I'll do my Turbo Duo when it comes to the YPbPr Component mod for -/GND. No, scratch that, it's a great idea!

You know what else would be good ?? Some hot glue over the wires as they come around right next to the the cap in your first photo instead of black tape. All that grounded area would be perfect to position all the wires over and hot glue 'em down to make things permanent. My wires, since they're not solid copper and *thin*, right where they've been soldered and are metalized by the lead/tin, if they're bended back'n'forth for like 4-8 times (it's unpredictable, but it's easy to happen) and what not, they'll break off... So some hot glue to permanently fix the wires down a little bit after they've been soldered somewhere I find is useful. Since the 6260 chip is on the bottom of a US Turbo Duo, I think it's a very good idea so that you'll never have to flip the PCB over again if there's a problem in the future. All the needed wires will be accessible on the top and very secure on the bottom. Just need to make sure you cut them at a good enough length.

Well, sucks that you didn't get a further improvement for the jailbar issue, but I bet it varies. At least the cap idea has a significant impact!

P.S. Quite a tangent, but I happen to have a Savings account in the Ethniki Trapeza of Greece, and it has a couple of thousand US dollars in it. I kinda think I should've emptied the whole thing out last time I was there in '08... Anyway, I notice you're in Athens, so what the hell is going on over there with these socialist 10% raids or whatever on bank accounts that they're talking about ? Is that limited to Cyprus or is that shit gonna spread elsewhere to Euro countries ?? The ole "running out of other people's money" is in full swing, eh ??
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 12, 2013, 11:32:07 AM
Thanks NightWolve, I try to make things as neat as possible when modding systems. As you can see the whole board is sqeaky clean, thats what you get after imersing the whole board under a significant amount of isopropyl alcohol. Being a chemist and working in a pharmaceutical company has its benefits :)

Actually I use hard disk ribbon cable stripes. The thin ones are from E-IDE ribbon cable and the gray thicker one from standard IDE cable. These cables must have very low resistance. The good thing with these cables is that they're really flexible. You can bend and twist them but they won't break inside. And you can get many many cable lines from just one ribbon.

As for the banks issue... there is none here. The "raid" on people's money (the ones that have more than 100000 euros in accounts) is limited to Cyprus.
Is it going to spread elsewhere? They're saying it won't but who knows these days... specially when the 4th Reich is running Europe.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 12, 2013, 03:10:14 PM
As for the banks issue... there is none here. The "raid" on people's money (the ones that have more than 100000 euros in accounts) is limited to Cyprus. Is it going to spread elsewhere? They're saying it won't but who knows these days... specially when the 4th Reich is running Europe.

Oh, pfffft, OK, it's for accounts over 100,000 EUR. It's a soak the rich raid. Yeah, then no problem (for me). The way it was reported made people paranoid! I hadn't seen that figure. But I believe I read that Spain/Italy or something were talking about the same sort of thing. Anyway, it's only some chump change left in my account so next time I'm visiting/vacationing, I'll have access to local spending cash. I was trying to decide if I should just cash out last time I was there, but I left most of it for that reason. Chicago actually used to have a Greek Ethniki Trapeza branch, but it closed some time ago (we are considered Tsipiana/Nestani here, hehe!). There is another one in New York for the Greek community there, so in theory, I could drive there with my Savings book and close it out if I got freaked out about the economic situation in Greece. That conversion to Euro sure was a killer man... For you and for Americans visiting...

Anyway, thumbs up on the modding! Good luck!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 12, 2013, 08:10:23 PM
I wouldn't worry about it, and from experience... if they're talking about such a thing, it aint gonna happen. What's the point of letting it be known to people so they can withdraw their money before it happens?
Take Cyprus for example... it happened before people had the chance to do anything, except the b@astards that had informations from within... (like Cyprus priminister's daughter for example).
Euro is nice.... specially when buying from the US :) but it can be a pain in lots of things.

ps
I may do the hot glue thing on it, I hate the sticky residue this insulating tape leaves after some time if you choose to remoe it. I don't particularly like the hot glue solution either but I don't see a better alternative.

edit...

Saturday morning eye candy :)

(http://img259.imageshack.us/img259/8462/dscn0107lz.html) (http://imageshack.us/photo/my-images/259/dscn0107lz.jpg/)

(http://img19.imageshack.us/img19/5190/dscn0101gs.html) (http://imageshack.us/photo/my-images/19/dscn0101gs.jpg/)

(http://img834.imageshack.us/img834/299/dscn0118lx.html) (http://imageshack.us/photo/my-images/834/dscn0118lx.jpg/)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 13, 2013, 06:15:58 AM
ok the pic brings up another point
your amp is sitting on top of digital signals
your signal wires cross power and data traces
shielding the amp and shortening the wires should help
also because that amp uses transistor bias resistors from its 5V supply, the supply needs a large filter cap on the amp board.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 13, 2013, 11:43:40 AM
There is no place onboard without digital signals that an amp can sit on. Actually there aren't many places that the amp can sit on and have the top shell being able to close completely. The location I picked is the most convenient, its flat (no caps there) and the top shell closes. There is also a 2mm thick double sided adhesive tape holding it in place so there is some spacing between the bottom of the amp and the top of the chips it sits on.
The wires cannot get shorter, take a look... no loose cables, straight from source to destination through the shorter possible path. How can they get shorter and reach the desirable points at the same time?

Yes I could shield the amp but I've never seen anyone do it on a PCE rgb mod and somehow, I don't think it will improve much (if any).

Anyway, the system went from "worse Jailbar system" to "best" within my PCE collection so it is a major improvement. Have you managed to make the jailbars completely disapear on your system? (with shieldings or whatever?)

The amp is constucted according to this design http://www.gamesx.com/grafx/pce_rgb.jpg (http://gamesx.com/grafx/pce_rgb.jpg) , its supposed to be PCE specific.

The jb aren't coming from the amp, they're comming from the 6260 chip and they were there even without the amp and I'm sure they will still be there on composite even if I disconnect the amp completely (although much weaker because of the tantalum caps). Maybe the 6260 chip needs shielding. Thats how the guy that completely solved the jb issue on the Famicom did it (by shielding the picture generator chip)... complete absense of jb, not the slightest sign of them.

Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 14, 2013, 11:27:26 AM
i have used a few different amp designs
have placed amp on top of slot shield, attached to top cover, and on back of DIN
the jailbars were subtle without the mod, and not seen with.
not seen may not be 100% but its close.
best amp is a simple transistor NPN emitter out, collector power, 5K resistor across a cap to chip pins.
the simplicity of the circuit makes it a low noise amp
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on April 14, 2013, 06:59:05 PM
> http://img259.imageshack.us/img259/8462/dscn0107lz.jpg (http://img259.imageshack.us/img259/8462/dscn0107lz.html)

Looks awesome! You know, I had an idea with the vias in my case given that my wires are separate, thin enough, etc. See those 4 vias aligned in square form that are right above your 3rd usage of hot glue going from the 6260 chip ?? Right there I was thinking I'd push the wires upwards and hot glue as well for good measure. That would shorten the path to the amp too! But anyway, yours looks great and you'll never have to flip the PCB over again, so all good!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 14, 2013, 08:49:44 PM
Somehow I doubt shortening the wires by a bit and shielding the amp does make a difference...
At first on my Core II, I added the amp externally to the console (right out of the console, a few cm after the connector), here's the thread with photos http://www.pcenginefx.com/forums/index.php?topic=9379.0 So no interference from digital signals coming from the PCE board there...
I still had the same intensity jailbars like on other consoles that had the amp internally.
After some time that i managed to make the amp smaller I remoded the Core II and installed the amp inside it. No change as far as jailbars go, exactly the same jailbars.
(http://img259.imageshack.us/img259/4381/dscn0025i.html) (http://imageshack.us/photo/my-images/259/dscn0025i.jpg/)

The jailbars were subtle without the mod steve because you were getting picture through composite (or worse through RF). Composite smooths the picture making the JB less visible. RGB mod makes them more clearly visible and not nesesarily because an amp "adds" more of them.

My jailbars are hardly visible too, I make comparissons on the initial gaming screen of the Keith Courage game in which the jailbars are more easily to be spoted due to the light blue color of the sky but on any other game only a trained eye can locate them, they are almost invisible but never completely gone.

Don't get me wrong, the theoreticly right way to do it is to avoid interferences by shortening cables and shielding the amp but practicly these two may make no difference. At least I haven't seen any and I've made many trials with the RGB thing.

I have even connected the RGB signals without any amp (bad colours) and noticed that the jailbars were exactly the same (with or without it).

Thats the reason I'm positive that the secret of completely removing the jailbars is doing something to the 6260 chip (like shielding it).

Actually on the Turbo Grafx-16 there is a shielded chip by factory but im not sure its the 6260, it probably is... (picture found on the internet)
(http://img254.imageshack.us/img254/7407/img0757mediumc.html) (http://imageshack.us/photo/my-images/254/img0757mediumc.jpg/)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on April 15, 2013, 04:15:42 AM
its ram i think
the 6260 is not sheilded
the jailbars are on the ground plane and 6260 ref low pin
thats why i have you add a cap across chip power and chip ref low to ground.
near as i can tell the jailbars are being caused primarily by the color encoder circuit, causing current pulses inside the 6260
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on April 15, 2013, 06:34:33 PM
Yes you're right, it's not the 6260 chip that is shielded on the photo. The 6260 is the chip to the most right.

I really wish there will be a way to completely wipe out these pulses so we can all get rid of these damn jailbars :) The caps are a significant improvement.

To my experience though, and the amp I'm using, there doesn't seem to be any other kind of interference adding up to the jailbars issue. This conclusion comes from several trials I've conducted myself, like comparing the same screen on RGB with or without the amp, with ground on pins 55-56 and with ground on the expansion port's ground or elsewhere, with amp inside or out of the console.
These trials showed no observable difference concerning the jailbars on one way or the other.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Kyle on November 09, 2013, 01:27:45 PM
[removed, sorry]
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Game-Tech.US on November 24, 2014, 06:56:03 AM
I've been asked about what cap sizes I use to recap the Duo, using surface mount ceramics instead of electrolytic leaded caps.
I show the process in this vid:
https://www.youtube.com/watch?v=xIIvEluVelU

Mouser is out of some of these, but this was what I settled on using:
77-VJ1206V106ZXQTBC 1206 10uF 10volts qty 6
77-VJ1206V475MXJTBC 1206 4.7uF 16volts qty 4
810-CGA6P3X7R1H335K 1210 3.3uF 50volts qty 1
963-LMK316F226ZL-T 1206 10V 22uF qty 19
81-GRM31CE70J476ME5L 1206 47uF 6.3volts qty 4
81-GRM31CD80J107ME9L 1206 100uF 6.3volts qty 10

What mouser didn't have I got off ebay, looked for known good name brand reels of 100uF and 47uF, iirc TDK and Taiyo Yuden.

I'd still like to know if any of these can be eliminated and a higher or lower uF value used, where it's not critical etc. Just to make it that much easier to order etc.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: cjameslv on January 08, 2015, 01:03:26 PM
I've been asked about what cap sizes I use to recap the Duo, using surface mount ceramics instead of electrolytic leaded caps.
I show the process in this vid:
https://www.youtube.com/watch?v=xIIvEluVelU

Mouser is out of some of these, but this was what I settled on using:
77-VJ1206V106ZXQTBC 1206 10uF 10volts qty 6
77-VJ1206V475MXJTBC 1206 4.7uF 16volts qty 4
810-CGA6P3X7R1H335K 1210 3.3uF 50volts qty 1
963-LMK316F226ZL-T 1206 10V 22uF qty 19
81-GRM31CE70J476ME5L 1206 47uF 6.3volts qty 4
81-GRM31CD80J107ME9L 1206 100uF 6.3volts qty 10

What mouser didn't have I got off ebay, looked for known good name brand reels of 100uF and 47uF, iirc TDK and Taiyo Yuden.

I'd still like to know if any of these can be eliminated and a higher or lower uF value used, where it's not critical etc. Just to make it that much easier to order etc.

The 47uf & 100uf back in stock just today. Been waiting forever. Your list came in at 12.77 + shipping. I chose the $4.99 usps shipping
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Game-Tech.US on January 08, 2015, 01:21:38 PM
I always kick in the extra few $s to go ups, I did that cheap service once and it took like 2 weeks.
I think they use ups to your post office then whatever from there, so it takes longer...
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: cjameslv on January 15, 2015, 03:22:57 AM
Part arrived yesterday, so took a week which i don't think is bad for cheapie shipping.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SmokeMonster on February 26, 2015, 01:49:16 PM
Thanks for the great chart. I had it open on my monitor andj also printed off Console5's (http://console5.com/techwiki/images/9/9a/Turbo-Duo-Cap-Map.png), and the recap was a breeze. One suggestion would be to upload a higher resolution version, so it can be blown up larger.

I used all Panasonic caps. When I powered it up, the CD-ROM even started to spin for the first time. The picture and audio are fantastic now, and I'll do some more with the CD when all of my buttons are out of their retr0brite treatment. I bought my Duo for peanuts because it was sold for parts as "completely broken".

(http://s11.postimg.org/tg5h8z93n/t_DSC4043.jpg) (http://s13.postimg.org/uac9rf1uv/DSC4043.jpg)

I was inspired by the capacitor charts posted here and did some of my own for the Neo Geo CDZ (http://www.theisozone.com/tutorials/neogeo-cd/hardware-and-modding/neo-geo-cdz-capacitor-replacement-chart/) last week.

A huge thank-you also to Game-Tech.US for posting so many great tutorials on youtube.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Waterclocker on February 27, 2015, 09:24:19 AM
I've got a couple Duos I will be recapping soon.  Definitely will using this guide.  I'm curious is anyone has noticed a difference in sound quality between different types of caps.  I've heard ceramic caps are not the best option for audio circuits.  I will probably use the Panasonic FC series, but I'm wondering if audio grade caps would make the audio even better?  I would probably use ELNA Silmic 2s.  Most are probably just glad to get their Duo working, but I'm wondering it this would make a noticable difference.  Any thoughts?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: SmokeMonster on February 27, 2015, 11:50:17 AM
I'm wondering if audio grade caps would make the audio even better?  I would probably use ELNA Silmic 2s.  Most are probably just glad to get their Duo working, but I'm wondering it this would make a noticable difference.  Any thoughts?
I certainly don't think they would hurt, but I am skeptical that you would be able to differentiate and improvements.

That said, if you are replacing audio caps it makes perfect sense to use nice audio graded caps if you have them on hand. Almost anything will be a big improvement over the stock setup. My Duo had a few ELNA caps and a Rubycon or two, but most were garbage Chang caps, and they are all very old and degraded by this point. I was surprised at just how badly the caps had fared in my Duo.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: mickcris on February 28, 2015, 04:30:15 AM
I've got a couple Duos I will be recapping soon.  Definitely will using this guide.  I'm curious is anyone has noticed a difference in sound quality between different types of caps.  I've heard ceramic caps are not the best option for audio circuits.  I will probably use the Panasonic FC series, but I'm wondering if audio grade caps would make the audio even better?  I would probably use ELNA Silmic 2s.  Most are probably just glad to get their Duo working, but I'm wondering it this would make a noticable difference.  Any thoughts?

It would be a good experiment if you got both sets of caps for the audio and tried them one at a time.  Probably the only way to tell if there is any difference.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Waterclocker on March 04, 2015, 05:28:09 AM
Thanks for the comments!  Good idea!  I started to swap out some caps, but I'm noticing that my DUO-R sounds way way better.  I've changed SMT caps in the op-amp area with new Silmic 2s, but have noticed no improvement over the old caps that were possibly still good.  The DUO-R is louder and is much more dynamic with better mid range and bass.  Both original DUOs I have sound the same.  Does the DUO-R have a better sound circuit?  Going to keep changing caps, but need to order more.  I hope I can get the DUOs I have to sound as good as my DUO-R at least.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Waterclocker on March 04, 2015, 07:06:45 AM
Reading the sound fix thread now, going to try replacing the radial leaded caps that are next to the vr heatsinks.  Makes sense that the heat could have dried them out.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on March 04, 2015, 07:17:02 AM
they leak
the failure to run on the radial caps is from corrosion
the SMD ones dry out
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: MNKyDeth on October 31, 2015, 03:46:48 AM
I normally buy my caps from Mouser but I was in a bit of a rush and didn't take the time to make out a list for what I needed so I ordered a cap replacement kit from Console5.

My question is related to the cap themselves mostly. I see they included a lot of caps with the right uF values but the voltage ratings are different.

An example is I know a spot needs a 22uF 25v cap but all I have in my kit are 22uF 50v caps. Is it ok to go above the voltage as long as the uF rating is correct?

There are a number of caps that have the same values as the ones on the board just some like the one I mentioned has a rather large voltage difference.

Edit:

Also, is there a way to estimate how long a supercap will last in the Duo's? I am planning on replacing one with a 1.5Farad supercap hoping that it will last longer but I would also like to guestimate it's time for holing a charge so I don't lose my save files if I store my Duo for a while.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on October 31, 2015, 09:24:16 AM
An example is I know a spot needs a 22uF 25v cap but all I have in my kit are 22uF 50v caps. Is it ok to go above the voltage as long as the uF rating is correct?

Yes sir! Not only is it OK, it's better! I've answered this quite a few times here, spreading my newly acquired Le Steve knowledge.

http://www.pcenginefx.com/forums/index.php?topic=7012.msg298464#msg298464
16 V is OK/safe. The circuit board generally operates at ~5 Volts DC after the power regulator, so capacitors that are rated 10 V or above are safe. But the bigger they are, the better they are: they last longer, handle "ripple" better and sometimes there is power inverting going on so they need to be of higher voltage in that area of the board. This comes at the expense of size and $$$: a 25 V cap is physically bigger and more expensive than a 16 V cap, etc. Anyhow, I was confused about this as well when I got started, but there ya go. When replacing a capacitor, you simply need to match the capacitance value exactly, but the max breakdown voltage can be equal or higher (and higher/bigger is better/safer).

That voltage rating on a capacitor is the max breakdown voltage, meaning, if the circuit runs at or higher than that, the capacitor is gonna start to overheat, break down, be destroyed, etc.

Most electronics run at 5 Volts DC here, so 16V rated or better caps are fine.

Sometimes, you don't want to be too close to the normal operating voltage though - it's always better to go bigger if you got the space and don't care to have paid more $$$!

E.g. I have a power supply for a 19" LCD TV given to me for servicing that had both 5VDC and 12VDC power outputs. The 12VDC area had 16V caps for regulation which broke down and killed the TV. Given the extra heat in the area, the manufacturer went too cheap and should've used 25V rated caps which would've been a little harder to fit given the PCB design, but possible. So only after 3-4 years of service, this new TV was dead for something as simple as a few capacitors...

Here's a video from the EE I learned a few things from:

https://www.youtube.com/watch?v=Ytw57212X2o

He has a dumpster diving TV/monitor repair segment/feature. People throwing away TVs and LCDs that mostly failed due to cheap capacitors in the power supply area for reasons like this which he finds/is given for amazingly cheap repairs most anybody can do! Cheap CapXon brands and rated just a bit too close to operating output voltage is a typical reason for failure.

Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: JoeQuaker on November 11, 2015, 06:22:53 AM
I really need to get around to replacing the caps in my TurboDuo (the all-black model). Everything still functions fine but the audio is really, really weak.

I just dread starting the job as everything looks so tiny and I've never soldered on anything surface-mounted. I'm more used to replacing caps in things like arcade monitor boards and Commodore 64 floppy drives.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: PunkicCyborg on November 14, 2015, 01:35:55 PM
(http://i.imgur.com/RB567egc4ca.jpg?1)
Recapped a turbo duo. Kind of a pain in the ass using leaded caps. Next one I do will be all tantalums or ceramics for the SMD smd stuff.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gahrling on December 13, 2015, 12:39:40 PM
Hey, new user here :)

I'm attempting to rescue a Turbo Duo unit from death and stumbled across this guide. I intend to do a full cap replacement as starters before performing an RGB mod, though I may need some assistance.

For the cap replacement I want to go the SMD Tantalum route but I'm a bit uncertain on a couple of things:

1. Case size. Will I be able to get away with case size B for all SMD replacements? For instance the original 22uf and 100uf caps on the pcb have completely different physical sizes, the 100uf having approx double the diameter.

2. Voltage. When shopping around for Tant caps I've seen some listing as 'V' and others as 'V dc'. Can I use both types or is one not recommended for this project?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: thesteve on December 13, 2015, 06:07:14 PM
as far as tant caps, you want to uprate the voltage
V is VDC
for most of the caps i use ceramic 1206
the 100uf6v i use 100uf 16v tant
47uf use 2 22uf ceramic
everything else is leaded and use aluminum like original
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: gtsamour on February 02, 2017, 06:40:24 AM
I have a question guys...

I replaced all the caps on my PCE Duo with smd caps. Do some 22uF electrolytic caps that are located on both sides of the board (black square ones) also need to be replaced?

I have some 22uF tantalum ones, is it OK to use these instead of the electrolytic ones? I used the same ones for the jailbar fix for pins 41/42, 43 pins of the 6260 chip.

(http://pic.photobucket.com/bwe.png) (http://s1169.photobucket.com/user/gtsamour/media/DSCN0107.jpg.html)

Thanks
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on October 04, 2017, 10:31:37 PM
(http://www.tapatalk.com/groups/pcengine/imageproxy87ee.jpg?url=http://i130.photobucket.com/albums/p266/Rockguard/PCEngineDuoTotalCapReplacementRefer.jpg)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: farankoshan on February 26, 2018, 04:36:06 AM
Has anyone ever updated this thread with definitive voltage ratings for each capacitor?
I’m a little bit confused as to why some sites report differing ratings.

For example, Console5’s list has nothing besides 6v or 16v. Is that accurate to say?
The site does sell a full capacitor set, including capacitors to improve the saving capability, as well as to help with a jailbar fix. But I’m unsure about values now.
Here: https://console5.com/wiki/Turbo_Duo

Meanwhile, GameDoctorHK has varying voltage ratings depending on the capacitor. Could be based on the original ratings that came factory-stock on the unit (but that’s only a guess).
Here: http://gamedoctorhk.com/index.php?main_page=product_info&products_id=1143
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: farankoshan on February 26, 2018, 04:51:47 AM
Has anyone ever updated this thread with definitive voltage ratings for each capacitor?
I’m a little bit confused as to why some sites report differing ratings.

For example, Console5’s list has nothing besides 6v or 16v. Is that accurate to say?
The site does sell a full capacitor set, including capacitors to improve the saving capability, as well as to help with a jailbar fix. But I’m unsure about values now.
Here: https://console5.com/wiki/Turbo_Duo

Meanwhile, GameDoctorHK has varying voltage ratings depending on the capacitor. Could be based on the original ratings that came factory-stock on the unit (but that’s only a guess).
Here: http://gamedoctorhk.com/index.php?main_page=product_info&products_id=1143


I bring this concern up (and I would really appreciate anyone who can shed light on this) because I recently had my cd spindle stop spinning. Unsure what caused it to stop, but I just opted to do a full cap replacement. I followed the GameDoctorHK values, and though my HuCard slot works, my CD spindle and lens still refuse to work. Can a wrong voltage rating on a capacitor cause a malfunction like this?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on February 26, 2018, 10:18:31 AM
Voltage can be the same or above the rating needed. Meaning if the cap requires 16v you can use 16v,35v etc....you just can't go lower.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: NightWolve on February 26, 2018, 11:32:00 AM
You must match the capacitance value, but like he said, the max breakdown voltage can always be rated higher, the higher the better.

If the board runs at 5V, you should use a 16V rated cap, it'll be totally safe, can handle spikes, heat better, etc. I have seen TVs break simply because they used a 16V cap in the power supply to regulate 12V for the backlight screen lamps. The caps overheated and popped at the top. Always better to use a 35V cap on a 12V area, especially near a power supply since you've got all that heat from regulators and transformers.

The only downside is the cap will be bigger and more expensive the higher the rated breakdown voltage is. So if the space is there, use 35V if you can especially if you got cheap Chinese caps. No harm no foul, they'll just last so much longer.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: farankoshan on February 26, 2018, 04:05:37 PM
You must match the capacitance value, but like he said, the max breakdown voltage can always be rated higher, the higher the better.

If the board runs at 5V, you should use a 16V rated cap, it'll be totally safe, can handle spikes, heat better, etc. I have seen TVs break simply because they used a 16V cap in the power supply to regulate 12V for the backlight screen lamps. The caps overheated and popped at the top. Always better to use a 35V cap on a 12V area, especially near a power supply since you've got all that heat from regulators and transformers.

The only downside is the cap will be bigger and more expensive the higher the rated breakdown voltage is. So if the space is there, use 35V if you can especially if you got cheap Chinese caps. No harm no foul, they'll just last so much longer.

Voltage can be the same or above the rating needed. Meaning if the cap requires 16v you can use 16v,35v etc....you just can't go lower.

Thanks for these notes guys. Will keep that in mind. :) Big help!

However, although we can go out and buy 35v for virtually everything is space inside the console was no problem (or if availability of those caps wasn't a problem either), for peace of mind & reference, will Red Ghost ever update that capacitor list? He did a great job with the cap list on the PCE CD-ROM2 a while back. I used that and never looked back. :)

Just so we can have the actual values on hand so we know how much higher voltage ratings we can look for.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Echoes on January 03, 2021, 06:33:58 PM
Does anyone have the values for the capacitor that should be in the spot marked C001? It seems to be missing on the Duo I picked up and that one doesn’t seem to be listed on most charts I can find.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on January 03, 2021, 07:51:29 PM
Is this for a pc engine duo? There is one spot on the board that is missing cap from the factory and is supposed to be like that.

Post a picture of the spot on the board here and I'll let you know.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Echoes on January 03, 2021, 08:55:40 PM
Is this for a pc engine duo? There is one spot on the board that is missing cap from the factory and is supposed to be like that.

Post a picture of the spot on the board here and I'll let you know.

It's a US Turbo Duo, the spot is the white circle right there by the corner of the drive.

https://ibb.co/jVvmMrw (https://ibb.co/jVvmMrw)
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on January 05, 2021, 07:07:24 AM
Oh, that cap isn't important at all. Some systems don't even have one there leaving the solder points empty. I'll check what the rating on the cap when I have another DUO opened up. I know it's a ceramic cap but forgot the value.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: demianph on September 21, 2022, 09:55:25 AM
Is this for a pc engine duo? There is one spot on the board that is missing cap from the factory and is supposed to be like that.

Post a picture of the spot on the board here and I'll let you know.

It's a US Turbo Duo, the spot is the white circle right there by the corner of the drive.

https://ibb.co/jVvmMrw (https://ibb.co/jVvmMrw)

Sorry for the necro but so the information is available I am replying.
Have mine open to re-cap (I found 5 definitely leaked surface mount caps).

Mine was manufactured October 1992 and has the cap.
Markings are:
   B
103K
symbol that looks like a M inside a C (manufacturer mark maybe) then 03

Internets say this is 10000pF (.01uF) with a +/- 10% tolerance and voltage is 50/100 volts (the underline). I think the B is the temperature code or flammability rating which it appears no one uses anymore.


Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: qingtongyoushou on November 15, 2022, 09:05:13 AM
I am helping my friend fix his PC-Engine and this is very useful information :D
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: game freak99 on November 15, 2022, 02:37:07 PM
I got a PC engine Duo that still has sound issues despite having what looks like a new set of caps. Do any of them look like the last owner missed them?

https://imgur.com/a/c7tbzPh
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on November 15, 2022, 04:22:38 PM
Just changing out the capacitors is only part of the work. Lots of times there are damaged traces and or shorts in via holes that need to be repaired during a capacitor change. This is most likely the problem as to why you are still having sound issues.

So the connections for the capacitors need to be checked to make sure the traces all have continuity and that the via holes have the correct continuity through them as well.

there is also the possibility of some old capacitor fluid being underneath one or more of the op amps or even possibly some of the resistors on the board.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: game freak99 on November 15, 2022, 08:52:07 PM
I just got a set of opamps in the mail today so I'm going to replace at least the one closest to the power regulators.

On the subject of the power regulators I'm reading 12v from the leg that feeds the opamps and supposedly it should be  only 8v. Then the transistor that is between the power regulator and the opamps is only outputting 1.6 volts. Do any of those parts sound like a likely culprit to you?
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: Keith Courage on November 15, 2022, 09:33:20 PM
One pin should be around 12-13v and another 5v.

If the voltage regulators weren't putting out the correct voltage, either card games or CDs wouldn't be working at all. so the voltage regulators are probably fine.

There's probably a bad trace,shorted via hole, or old capleakage under an op amp somewhere in the area above the heat sinks.
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: game freak99 on November 15, 2022, 11:42:24 PM
That makes sense. Could there be something wrong with q304 making it only output 1.6 volts instead of 7-8 like it's supposed to? Or maybe something upstream from pin 1?

Also, when I first tested the unit there was extremely quiet sound, but after I washed the board with 99% isopropanol (lots of brown gunk on my qtips!) there was none. Could I have loosed up some capacitor gunk from the board and ended up getting it into worse places?

Thanks for your advice!
Title: Re: REPAIR GUIDE - TurboDuo/PC Engine Duo: Total capacitor replacement chart
Post by: djbunyan on January 07, 2023, 07:20:14 PM
Hello! Is anyone in here willing and able to help me fix a PCEngine Duo?