PCEngineFans.com - The PC Engine and TurboGrafx-16 Community Forum

NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: D-Lite on May 29, 2005, 03:50:44 PM

Title: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: D-Lite on May 29, 2005, 03:50:44 PM
Haha, not the biggest news in my world, which would be the Turbo Duo sound fix, but this is the other scourge of the Turbo World!  

I was discussing the problems with Duo units with TZD's Steve and he mentioned that by far and away the biggest problem for them has been weak/no sound from Turbo Express units, even brand new ones!  So I asked if he could send a unit of two and I'd look into it.  Tried contacting RetroGames Bob Frasure, but no luck (still, if anyone has a way to contact him please let me know!).  So off I went with the multimeter.

So I sat with a TE with a weak speaker and started tracing the circuit back, looking for the culprit which I figured had to be a dead/dry capacitor or dead op amp IC.  Since there is a dense mask on the system, I had to do a lot of scraping and shining of light through the PCB to find the contacts.  Here's what that looked like:
(http://www.multimods.com/TEsound/Cap2a.jpg)
Notice the Op Amp for the sound highlighted and two little holes through the PCB.  These holes are the + and - of a capacitor that leads to the input into the op amp for the audio are also tied to the speaker line which is just above the "03" in L103 on the PCB.  Those holes are connected to this capacitor:
(http://www.multimods.com/TEsound/Cap1a.jpg)

So, I figured, likely culprit.  I tapped a new 100 uF, 25 Volt capacitor to the proper holes and SUCCESS@!!@!!   The sound amplified to a normal level!!!!!!  What I've noticed is that there are varying degrees of the sound issue from weak sound to no sound.  This mod works with both and even in the worse case it is amped to a satisfactory level.  Meaning there is likely another cap somewhere that needs looking at, but this fix will definitely work.

Here's step-by-step instructions on how to do this.  I can't make linking pics here to the bigger versions of these, but if you copy the location of the image I have and simply remove the "a" that's after the number, before the ".jpg", then you will get the 800 x 600 version.
All these are in this folder on my site:
http://www.multimods.com/TEsound/

OK, on the back of your TE, remove the 4 screws on the outside and the two inside the battery compartment:
(http://www.multimods.com/TEsound/TE1a.jpg)

CAREFULLY separate the front and back of the unit enough that you can disconnection these connections.  The flat cables should be wiggled gently back and forth to make them loose.
(http://www.multimods.com/TEsound/TE2a.jpg)

On the rear part of the unit, remove the screw indicated in the pic.  Note that the two holes we're soldering too are located where the arrow is pointing:
(http://www.multimods.com/TEsound/TE3a.jpg)

Closeup of the holes with + and - indicated.
(http://www.multimods.com/TEsound/TE4a.jpg)

Here's the culprit.  You can twist the cap off with a pair of pliers but leaving it in is no problem.
(http://www.multimods.com/TEsound/TE5a.jpg)

Now take an electrolytic 100uF cap (25 V is what I used, but you can use 10V, 15V, etc) and connect two wires to it, preferably close to the cap body as shown so most of the wire and terminals are coved by insulation.  I used wrapping wire (30 gauge), but you can use 22 gauge, which is pushing it on how small the spots you're soldering too are.  Wires should be about 1.5-2" long.
(http://www.multimods.com/TEsound/TE6.jpg)

And now connected:
(http://www.multimods.com/TEsound/TE7a.jpg)

Here I've tucked the cap under the PCB where there is ample space to hold it.  Note in the picture I have also added a short wire between two places on the PCB.  This is connecting the right and left channels on this unit since the right channel was dead.  I'm sure the issue with it can be solved, but this works great for addressing the problem at hand.
(http://www.multimods.com/TEsound/TE8a.jpg)

Now with the PCB reset to it's place, note the location of the wires.  All you have to do now is screw in the proper screws and reconnect the cables (carefully!  I use needlenose pliers for the flat cables so I don't bend them) and you're done!!!
(http://www.multimods.com/TEsound/TE9a.jpg)

So, there it is.  You can buy the capacitor dirt cheap in packs of 10-100 from DigiKey or Jameco and even Radio Shack has the capacitor.  All you need after that is 3" of wire and soldering equipment.  Oh, and a small Phillips head screwdriver.

If you need yours fixed, I will probably start offering to fix them for people shortly.  Shipping plus maybe $10 for the fix.  So about $20 shipped back to you (you pay shipping out, and then it's about $10 back to you).  I figure there are a lot of people that are nervous about soldering such small connections and opening anything electronic like this, so I'll probably offer to do this.  We shall see on this, but most importantly I wanted to make this available for everyone!  

Next biggy, and the one I'm most passionate about, the Duo sound issue!!!
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: nodtveidt on May 29, 2005, 04:08:26 PM
Excellent man. Very excellent. :)
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: DragonmasterDan on May 29, 2005, 04:15:37 PM
That's cool, the only problem I've had with my TE is that the turbo switch will actually disable my I button when its stuck in between normal and the low level turbo. I've heard quite a bit about the sound issues though, at one point I thought I had that problem. It turned out I needed new batteries :-D
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: esteban on May 29, 2005, 04:29:45 PM
Simply superb. :D
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: zborgerd on May 29, 2005, 06:00:30 PM
Nice find.  This is as I've expected for some time (as it's the most logical failure point), but I've not had a broken one one to test this theory.  I suspect something similar going on in the Duo systems, but it's undoubtably a much bigger task since there are two seperate audio circuits (one for typical FM synthesis and the other for CD audio).  CD audio isn't particularly complicated though.  It normally consists of (after the drive) only a DAC and an opamp, and a few other little things like caps, so it really should be pretty simple.

I know that you marked the polarity, but it is important to stress to everyone that these caps are *polarized* and you can blow the electrolytic caps if you have it soldered in backwards.  Also, pulling apart a Turbo Express can be pretty complicated for novices.  It takes a bit of care to get everything back in there just right.

Nice work.
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Keranu on May 29, 2005, 06:29:44 PM
Awesome information. I'll look to you if I ever get an Express (which I surely will some day) and need help with that problem.
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: D-Lite on May 29, 2005, 07:56:09 PM
Quote from: "zborgerd"
Nice find.  This is as I've expected for some time (as it's the most logical failure point), but I've not had a broken one one to test this theory.  I suspect something similar going on in the Duo systems, but it's undoubtably a much bigger task since there are two seperate audio circuits (one for typical FM synthesis and the other for CD audio).  CD audio isn't particularly complicated though.  It normally consists of (after the drive) only a DAC and an opamp, and a few other little things like caps, so it really should be pretty simple.

I know that you marked the polarity, but it is important to stress to everyone that these caps are *polarized* and you can blow the electrolytic caps if you have it soldered in backwards.  Also, pulling apart a Turbo Express can be pretty complicated for novices.  It takes a bit of care to get everything back in there just right.

Nice work.

Thanks.  I really enjoy this stuff so figuring out solutions like this keeps me going.

With regards to the Duo, I've traced the circuits and I know where all the op amps are and I can figure out the caps.  BUT, and this is a big BUT, like JLo big, I can't easy test which it is because I need to physically access the caps while the lid is on since I need the CD cover in place to hold the disc.  I think I have the solution to that though.  Hoepfully I'll have the *cure* posted for that soon too :twisted:
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: twor2005 on May 30, 2005, 07:31:21 AM
Good work. In fact this deserves better than a post on a forum. Maybe Aaron will put this on the site!
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Liquid Snake on June 01, 2005, 01:05:15 PM
D-Lite is the man!!!!!!!!!!!!!!!!!!

You wanna to show us your TG/PCE game/console collections?
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Pcenginefx on June 03, 2005, 06:20:47 PM
Great work D-Lite!  I read over your instructions and seems pretty straight forward to follow.  Speaking of TE's, I have a TE that is in need of the sound fix and I'd rather have you do this than me....when you taking orders? :)
Title: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: shadowlife25 on March 19, 2006, 09:10:16 PM
Hey D-Lite, I just wanted to say thank you for posting such an informative (and picture filled :) ) rewiew and also i wanted to say that the sound fix works wonderfully. now if I could just figure out how to do the screen fix...
Anyhow, many thanks!
M.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: ctoomey on February 16, 2007, 08:46:04 AM
I did this fix today and it works like a charm. Thanks so much for the post!

I would be willing to fix peoples units if there is a need out there.

If you would like to discuss please let me know via email: ctoomey75@hotmail.com

Thanks again D-Lite
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Keranu on February 16, 2007, 11:28:13 AM
I still need this done for my Express, but still not sure if I should do it myself or not.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: ctoomey on February 16, 2007, 11:34:38 AM
I have decided to do this for a limited number of folks that need it. Check out the forum topic TURBO EXPRESS SOUND REPAIR for details. Thanks!
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: GUTS on February 16, 2007, 05:49:12 PM
Haha I did this fix on a friend's express with a part from a dead Xbox motherboard.  Awesome.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: grahf on February 17, 2007, 08:00:23 AM
For anyone with the means to solder smaller stuff, you can get the SMD caps identicle to the bad ones at mouser.com. Im pretty sure thats where i got mine. Im going to replace ALL the caps in my nicest unit.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: grahf on February 18, 2007, 12:35:24 PM
Well, I replaced all four caps in the audio amp circuit. The result is perfect sound. This thing is LOUD, way louder than my DS or GBA. I cant believe this is how its supposed to sound, after listing to it in wisper-mode all this time :D

I was mistaken, I got the caps from Jameco. I can provide part numbers if anyone is interested. The hardest part of this job is removing the shields. A bit of desoldering braid is needed, and a fine tip soldering iron is a MUST. The picture below is of my parts/project GT, and has the handsfree jack removed as well. You dont need to remove it (I didnt on the one I did today), but it would give you more room. I'm going to go back in later and replace the rest of the caps for good measure.

(http://files.myopera.com/grahf/albums/102941/audio%20caps.jpg)


Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: FM-77 on February 19, 2007, 02:59:49 AM
What the hell happened there in the corner? :P
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: grahf on February 19, 2007, 04:02:37 AM
Some parts of the PCE GTs come coated with this rubbery/glue junk. I just scraped it away a bit to see underneith on this board.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: esteban on February 19, 2007, 04:03:08 AM
What the hell happened there in the corner? :P
Obviously, the marshmallow he was eating fell from his mouth and melted on the board. :)
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: grahf on February 24, 2007, 08:13:56 AM
you know, for the most part the Express/GT is very well constructed (just like the PCE). But i cant for the life of me figure out why they felt the need to cover certain things will goop. Its common practice to coat some things, but not just randomly glob it on there.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Michael Helgeson on February 27, 2007, 09:12:35 AM
They did it to insulate that area I guess,assuming it is a more high risk area of the pcb component wise.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: grahf on February 27, 2007, 10:19:04 AM
Yeah, but one must wonder why they didnt just use the common shellac style coating. Maybe they thought the glue would help the heavier components from jolting loose from a drop.

Or, maybe someone brought their kids into work with their elmers glue bottles :lol:
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Tatsujin on February 27, 2007, 11:38:18 AM
question: isn't it just that easy to replace only this 100uF/6V capacitor?

:edt: grahf already mentioned about that. fine :)


btw: did someone try to use doublelayer/tantalum capacitors instead of electrolytic, since they can't dry out, which causes the problem of losing the sound. of course i'm aware, that for audio applications there isn't something better than the good ol' electrolytic caps. but we're not talking about HIFI here ;)
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Tatsujin on February 27, 2007, 03:02:36 PM
Yeah, but one must wonder why they didnt just use the common shellac style coating. Maybe they thought the glue would help the heavier components from jolting loose from a drop.

Or, maybe someone brought their kids into work with their elmers glue bottles :lol:

seems like it's the part for stepping up the voltage which is needed for the neon-lamp for the backlight (about 100VAC). sometime parts, especially coils have to be fixed/reinforced with some glue to the PCB, since they shaking slightly in a high frequency, which could cause a broken soldering over the time of use.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: ctoomey on March 02, 2007, 07:43:48 AM
I've done this on a few units with success but experience a bit of 'hum' in both the speaker and when listening through headphones...I have not pulled the dry/old capacitors since it doesnt seem necessary and I am using 100uf 50V capcitors...

Thoughts on how to limit the hum?

Thanks!!!
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: grahf on March 02, 2007, 09:18:57 AM
I get the same hum, and im pretty sure its normal. I dont know how it is on yours, but on mine it only occurs when the volume level is pretty high. My portable dvd player does the same thing (as do a lot of electronics).
It is also possible that one of the other dry caps on the board is allowing interference to bleed into the audio. When I have time I may replace all the other caps on the board, but its no rush because it sounds normal to my ears.
Title: Sound back now...
Post by: Tighe on March 10, 2007, 03:15:20 PM
Hey D-Lite, I just wanted to say thank you for posting such an informative (and picture filled :) ) rewiew and also i wanted to say that the sound fix works wonderfully. now if I could just figure out how to do the screen fix...
Anyhow, many thanks!
M.


About a year ago my beloved TE's sounds kept getting quiter and quiter, until one day the video stopped being displayed too!  I was so sad and knew if I spent a lot of time I could figure out the faulty circuit, but I just didn't have that time.  After reading this post, I was so excited I ran to the basement and replaced the capasitor as suggeted, and WOW the sound was back!!!  Now the real question is will replacing all the capisitors return the video?  The backlight still works, I can ouly assume that the problem is with the main board not the video driver.  I will be ordering exact replacements as they will be much easier to install.  I will post here with the results.  Thanks D-Lite!

http://nestable.classicgaming.gamespy.com (http://nestable.classicgaming.gamespy.com/)
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: ctoomey on March 10, 2007, 03:49:14 PM
Cool! Where are you ordering the replacement vid caps from?
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: ctoomey on March 12, 2007, 12:20:03 PM
Grahf, I was curious why you replaced all 4 of the caps...It seems that just following D-lite's sound fix works well, even if you leave the old ones in place?
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: grahf on March 12, 2007, 03:18:46 PM
Just replacing the single cap did not work for me. In fact, it made the sound stop working alltogether. The audio opamp NEEDS all four of those caps by design, but it just so happens that the one D-lite pointed out is most crucial for operation and will fix most peoples problems (but probably not 100%).

I dont think the screen can be replaced by replacing caps. The screen takes RGB input, and from my tests the signal comes almost directly off of the hu6260. Sounds like your screen itself is bad, and unfortunatly it probably cant be fixed. Old lcds like these are just really flakey.
When I have time, I have a modern LCD from a pocket tv that I plan on hacking to take RGB, and putting that in one of my Expresses. It will be nice to have a system with modern LCD.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Tighe on March 14, 2007, 12:02:12 PM
Just replacing the single cap did not work for me. In fact, it made the sound stop working alltogether. The audio opamp NEEDS all four of those caps by design, but it just so happens that the one D-lite pointed out is most crucial for operation and will fix most peoples problems (but probably not 100%).

I dont think the screen can be replaced by replacing caps. The screen takes RGB input, and from my tests the signal comes almost directly off of the hu6260. Sounds like your screen itself is bad, and unfortunatly it probably cant be fixed. Old lcds like these are just really flakey.
When I have time, I have a modern LCD from a pocket tv that I plan on hacking to take RGB, and putting that in one of my Expresses. It will be nice to have a system with modern LCD.

Actually in my case I tested the screen and it is functional, the problem is with the system board.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: nat on March 21, 2007, 04:33:18 PM
Just replacing the single cap did not work for me. In fact, it made the sound stop working alltogether. The audio opamp NEEDS all four of those caps by design, but it just so happens that the one D-lite pointed out is most crucial for operation and will fix most peoples problems (but probably not 100%).

I dont think the screen can be replaced by replacing caps. The screen takes RGB input, and from my tests the signal comes almost directly off of the hu6260. Sounds like your screen itself is bad, and unfortunatly it probably cant be fixed. Old lcds like these are just really flakey.
When I have time, I have a modern LCD from a pocket tv that I plan on hacking to take RGB, and putting that in one of my Expresses. It will be nice to have a system with modern LCD.

Thanks to your post in another forum, I found out my GT isn't dead after all. The fuse was just blown. I  bypassed the fuse and all is well.

However, I uncovered a different problem. I replaced the one cap D-Lite mentioned but my aduio is still not working. In fact, it didn't help anything  at all. Looks like I need to replace the other 3 as well. Will you post those part numbers?
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: grahf on March 21, 2007, 05:08:33 PM
Yes, no problem. I ordered the replacement caps from www.jameco.com (http://www.jameco.com/)  You have to search by "catalog #".

You need two "193017". The originals are 33uf 6v, the jameco replacements are 33uf 16v.
You need two "192903". The originals are 100uf 6v, the jameco replacements are 100uf 6.3v.

Just a few pointers: you WILL need to pick up some desoldering braid for this job (radioshack). You have to remove the shields, and some of the posts are impossible to get to with a desoldering tool. A well placed piece of braid and fine tip soldering iron will make things easy. Also, it can be hard to get to the 100uf caps if your soldering iron isnt small enough. You can desolder the headphone jack for easier access. Its a lot more work, but it depends on what your working with. Good luck!
-Ben
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Torx on June 09, 2007, 07:57:25 PM
WOOTTT!!!!  i just repaired mine!
man i got scared as heck, i accidentally got molten solder on the tiny little transistor rectangle thing and accidentally pulled it up a little..  i almost fainted..
then i heated it up and push it down..  put it back together with fingers crossed and it works great!!

thank you d-lite and others, when i got time and money i'll be replacing all of them..  but as of now.. the sound is great and loud!
i left the cap in just in case others are wondering..

i just hope this modfix wont have any ill effects in the future...
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: nat on June 10, 2007, 07:08:51 AM
My GT had audio that didn't work at all, not even with headphones. I ended up just replacing the one cap, which turned out to be a huge chore in itself. My hands are too large and unsteady to be working on a PCB that is so cramped and small. I blew the fuse in the process, which I luckily bypassed with no ill effects.

Anyway, after replacing the one cap, I now have loud sound over the headphones but the speaker is still dead. I'm going to leave it at that and call it good-- after reading what grahf suggests for replacing the other caps, I'm calculate an 85% chance of destroying my GT if I were to attempt it. Especially after the trouble I had with the "easy" one.

It's OK, because I would normally use headphones most of the time I played anyway.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: jimid2 on June 13, 2007, 02:40:37 AM
Well, I (well, a more technically adept friend of mine, actually) managed to get two of the caps replaced in my "headphones only" TE before giving up in nervous exhaustion - but it was enough! I've got sound!! Not loud enough to be heard on a bus, but plenty loud for playing on the couch in my home, even with the stereo on in the background.  :dance:

It's thanks to this post that I've got this far, and I wanted to say so! Mucho graçias!   :D
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: rastoma on September 27, 2007, 09:06:10 AM
Yes, no problem. I ordered the replacement caps from www.jameco.com (http://www.jameco.com/)  You have to search by "catalog #".

You need two "193017". The originals are 33uf 6v, the jameco replacements are 33uf 16v.
You need two "192903". The originals are 100uf 6v, the jameco replacements are 100uf 6.3v.

Just a few pointers: you WILL need to pick up some desoldering braid for this job (radioshack). You have to remove the shields, and some of the posts are impossible to get to with a desoldering tool. A well placed piece of braid and fine tip soldering iron will make things easy. Also, it can be hard to get to the 100uf caps if your soldering iron isnt small enough. You can desolder the headphone jack for easier access. Its a lot more work, but it depends on what your working with. Good luck!
-Ben

Hi Ben,

Thanks for the info.  Do you have extras of these?  Or does anyone here want to go in and buy them and split them? 

I know the cost is very cheap, it's not a matter of cost, I just hate wasting things or throwing something a way that's good.  I know I'll never use 10 each of these and only need 2 each as stated.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: ceti alpha on September 27, 2007, 09:16:16 AM
 :clap: Wow! I don't have a TE, but all the effort you put forth in this area is amazing!  :D And your step-by-step guides are awesome.  :clap:
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Wolfeman on October 09, 2007, 05:53:40 AM
Just replacing the single cap did not work for me. In fact, it made the sound stop working alltogether. The audio opamp NEEDS all four of those caps by design, but it just so happens that the one D-lite pointed out is most crucial for operation and will fix most peoples problems (but probably not 100%).

I dont think the screen can be replaced by replacing caps. The screen takes RGB input, and from my tests the signal comes almost directly off of the hu6260. Sounds like your screen itself is bad, and unfortunatly it probably cant be fixed. Old lcds like these are just really flakey.
When I have time, I have a modern LCD from a pocket tv that I plan on hacking to take RGB, and putting that in one of my Expresses. It will be nice to have a system with modern LCD.

Thanks to your post in another forum, I found out my GT isn't dead after all. The fuse was just blown. I  bypassed the fuse and all is well.

However, I uncovered a different problem. I replaced the one cap D-Lite mentioned but my aduio is still not working. In fact, it didn't help anything  at all. Looks like I need to replace the other 3 as well. Will you post those part numbers?




I have the same problem with my screen, can you post a photo of where the fuse is you're talking about?
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: WoodyXP on April 10, 2008, 08:01:26 PM
Thank you very much for posting this fix, Mr. D.  I was able to fix mine and it is LOUD!! 
My quality of life has increased immensely.   8)

And sorry for bumping this old assed thread.  :oops:
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: nat on April 11, 2008, 03:51:33 AM
I may have some information soon to add to this thread regarding the sound circuit. Stay tuned (pun intended).
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: chop5 on April 22, 2008, 05:57:25 PM
thanks dean did the 1 cap soldered to the two VIA's,works perfect :dance:
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: ceti alpha on April 23, 2008, 01:41:40 AM
I may have some information soon to add to this thread regarding the sound circuit. Stay tuned (pun intended).

groooooaaaaannnnn!!!  :P :P

Who am I kidding? I love cheesy puns.  :mrgreen:
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: vestcoat on April 24, 2008, 05:22:22 PM
Is anyone having problems with one of the stereo channels not working in the headphone jack?  Two of my 3 TEs have been fixed using D-Lites instructions but only output the left channel if I use headphones.  The third, with the common sound problem making the speaker so quiet it's almost inaudible, plays fine through BOTH headphone channels. :-k
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: nat on April 24, 2008, 05:23:55 PM
Replace both the 100uf capacitors in that cluster to equalize the volume for both channels.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: nat on July 02, 2008, 06:55:45 AM
I want to add something here.

Sometimes replacing the two 100uf caps doesn't completely fix the audio in these units. You also need to replace the two 33uf caps in sequence with them.

The one problem here is that 33uf caps are kind of hard to find, save for special ordering them online.

I did some testing and 47uf caps work 100% as a suitable replacement (and are much more common), and actually result in a louder sound volume than using 33's.  :!:

By replacing the 4 caps (2 100's, 2 33/47's) in the sound circuit, you will restore audio functionality to 100% unless you have a bad speaker. Also, both sound channels will be equalized over the headphones so D-Lite's shunt pictured on page 1 isn't necessary.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Vanquish on August 06, 2008, 01:53:52 AM
Hey! This is great. Just wanted to say thanks and CONGRATULATIONS!!!   :D
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Duo_R on September 12, 2008, 09:24:33 PM
Well - I performed the Audio and Video cap mod today....and I brought a Turbo Express back to life (both were bad).....am I hero? No. Did I save a life? Yes a Turbo Express! You know who is a real hero? Hiro from Heroes.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Ratix on September 13, 2008, 07:18:03 AM
so this is what you did last night >.> i sold both my TE's a very long time ago because of that sound issue i feel like a fool for soing it to because i got ripped off when i sold them.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Duo_R on September 13, 2008, 01:03:05 PM
Yes - I did it last night. It would have only been a 30 minute job but I saw some other caps that looked bad and I can't walk away without replacing. So it was a TE that had no sound and no video....and here it is now:

(http://img232.imageshack.us/img232/5046/0913080051fz6.jpg)

Video works, the sound is nice and LOUD both using the internal speaker and headphones.

Now I used a different technique than D-Lite, I like making things more similar to how they were when new, so I didn't use any wires to relocate the caps. I can post pictures if you guys want. I tried getting smaller caps (if any of you live near a Fry's this is the way to go) and in some cases got creative and mounted the caps more horizontally if space was an issue. Took lots of pics during the install, and I also have a technique on remove the original caps. I call it the "lift technique" and can describe in more detail if it is helpful. I will probably post this info up on my website (needs something new on it anyway).

Well - TE sweetness. There is a ton of room to work with in some areas on the TE. The first thing I am kicking around is getting a rechargable battery pack and plug so you wouldn't never have to swap batteries out again. If I could get a pack that is smaller than the 6 AAA's, then that would give some room for other projects. Here are a couple of ideas I have for this unit:

* built-in rechargeable pack
* upgrade to a 3-3.5" screen
* built-in memory unit (ala Turbo Booster Plus)
* RGB Out
* Controller port

Of course the purists would yell at me for considering this, but I can't help it. I figure if I bring something back from the dead I have a say on what to do with it (my Frankenstein theory).

So here is where I need some help:

donations of broken controllers, multitaps (so I can get controller ports and cables)
A Turbobooster that is no longer needed or allow me to "borrow" (I need to know what consists of the memory module and see if we can somehow shrink that down to fit)
Suggestion for an RGB screen (does Ben Heck just steal from portable TV's?) - the PS1 is too big
I don't want to do any external modification on the screen, I just want to fit on the inside with a larger screen. 3.5 is more realistic.

Now I haven't played this system in say 15 years, does the LCD sometimes carry ghost images? I remember being blown away by this system (and it is still nice) but of course having a PSP you really can't get better quality LCD these days. I somehow want to bring the screen up to date (and dead pixels aren't as much of an issue anymore).

But would you describe the LCD to be a little grainy, ghosty?

Well I want to make it look as good as it does on my PS1 LCD screen (looks killer).


(http://img169.imageshack.us/img169/213/0901081408apz3.html)

Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: ceti alpha on September 14, 2008, 04:47:48 AM
Nicely done.  :clap: :mrgreen:
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Duo_R on September 14, 2008, 10:29:36 AM
ok, first this is the technique I  use to remove the caps. Lift technique - you heat up one side of the SM cap, I use a little bit of solder and the iron and heat it up nicely. I then start to lift by either the use of a small jewelers screwdriver, or needlenose pliers. You just keep lifting until you can use the iron to remove all the solder connecting to the board. Be very careful, too much force and you could lift the other leg off the board.


(http://img47.imageshack.us/img47/7370/0912082301qf1.html)

Once you get one side disconnected, I then bend the cap back down to the original position (bending the other leg back). I then use needlenose and then twist back and forth until the other leg breaks.


(http://img155.imageshack.us/img155/2517/0912082307yl6.html)

Then I installed the caps again like so:


(http://img411.imageshack.us/img411/3446/0912082339auj8.html)

Note, I replaced both even though the guide says just one of them. Here is why -when I see a cap that doesn't look like it is in good condition, I replace it. Same theory for a mechanic, if you are already doing work and have parts taken apart, it makes sense to replace parts that might go bad soon since you already have things taken apart (well sense for your car, not for your pocketbook).

The other reason, is by removing both caps, I can install with the horizontal technique. You can see how I have one of the caps bent, this is before I bent the 2nd cap. After I looked at this picture I realized that it looks like one of the caps has the other one bent over.... :-"

Here is the final pics of the caps installed before I put the shield back on. Removing the shield isn't necessary, but wanted to peak under the hood.

(http://img258.imageshack.us/img258/2366/0912082343rr8.html)

You can see I also replaced the larger yellow cap - the same thing again about replacing things that look like they are going bad (leaking, etc). It is just easier to replace once for me and put back instead of opening up over and over. I put a little electrical tape since one of the caps is very close to some SMD parts. I didn't want the cap to bend a little when putting back into the housing and short something on the board. A little tape and it is taken care of.




Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Dazz on September 25, 2008, 01:07:20 PM
I would like this done to my Express, please PM me with price in mind.
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: agt_dale_cooper on November 19, 2008, 12:10:03 PM
Did this yesterday to two Express units, both work famously now.  Used Nat's idea for the 47 (as opposed to the 33) as well, and the thing is quite loud.  Disappointed to post, however, that the subminis I used from Parts Express (47uF 10V Sub Mini Radial Capacitor, 020-1604, and 100uF 10V Sub Mini Radial Capacitor, 020-1606) were actually LARGER than the original NEC caps, and I was forced to remote mount down the sides of the PCB.  Ordered/bought subminis in an express attempt to avoid remote mount, but these didn't fit, just a bit too tall.  Commented them as such on their site.  If you're looking for parts grab the physical dimensions of these from their site and see if Digi-Key or Mouser has smaller pieces....
Title: Re: REPAIR GUIDE - Turbo Express: Sound Fix
Post by: Duo_R on March 05, 2009, 02:21:05 PM
Just sharing the latest and greatest, this is how I am replacing these now (the whole audio circuit). You can fit two caps on the top of the audio jack port. And you can see where I am tucking the other two. I use a little hot glue to hold the cap on the left and use a little shrink tubing on it.

(http://img19.imageshack.us/img19/8171/img0040sjy.html)

Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Turbo D on March 15, 2009, 10:07:43 PM
Hello fellow PCEFXers!,

Did you replace all of the capacitors in the audio amp on your TE only to be slapped in the face with a 60-cycle hum coming out of your speaker? Do you need a solution? Then look no further! Pictured below is a capacitor worth replacing if you are experiencing a 60-cycle hum out of your speaker after you have replaced all of the capacitors in the audio amp. The capacitor is 100μF 6v and is located under the shielding.

(http://pic.photobucket.com/bwe.png)


turbo D's Quick tips!:

Quick tip 1:
60-cycle hum is usually caused by a bad capacitor and/or ground!

Quick tip 2
:
When installing a new capacitor, it is okay if the voltage rating is higher than the original capacitor as long as the microfarads (μF or MFD) rating is the same. This is because the voltage rating of the capacitor is a limit not a requirement. However, you cannot replace your capacitor with one having a lower voltage rating. Also, a capacitor with a higher voltage rating will theoretically last longer. Do note that the higher the voltage rating, the larger in size your capacitor will be.

Quick tip 3:
When installing a polarized capacitor, make sure you do not reverse the polarity when installing ( e.g. solder negative to positive and vise versa.) The result will be an explosion of acid! If you are unsure of which lead is positive or negative, remember this: the negative lead of the capacitor will have a strip of arrows above it. If you have a capacitor with leads coming out of both ends, then the negative lead will be the lead that the arrows are pointing to. This is because the electricity flows in to the positive and out through the negative, hence the arrows indicating flow direction. Simple!
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Charlie on May 23, 2009, 02:07:43 PM
Quickie here:
I see that attachments are limited to 128k, but my bmp files are like 2Meg.  What's the best way to get them posted here?

Thanks
Charlie
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Turbo D on May 23, 2009, 08:55:45 PM
I upload my pix through http://photobucket.com/. I usually re-size my pix with photoshop before uploading, but it is not required as photobucket will re-size them for you.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Charlie on May 24, 2009, 06:22:23 AM
For the technically interested, the TE audio circuit and signal path explained:

Note #1: This text relates to the follow three bitmap files. 

Note #2: The quoted characters in this text represent the identical characters in the schematic, which match the identical characters
shown on the PCB pics.  The uppercase circled points in the schematic represent both the vias as shown on the circuit board pictures,
and the quoted characters given in the text below.  Likewise, the lower case circled points and text represent the
headphone jack pins.  Numeric values represent component pin numbers; an asterisk is Ground.

For speaker :
From Pin 2 of VR100, the volume control to via "K", to headphone connection "g", to headphone connection "f" (switch between "g" and "h" is open without headphones inserted), to one of two amplifier circuits (A+) in IC100 (pin 7), out pin 1 to "B", to CC103, through CC103 to "C", through L100, to "G", on to L103 to headphone connection "e".  A normally closed switch inside the connector routes the audio to "d", which routes to the speaker.

For headphones:
From Pin 2 of VR100, the volume control to via "K", to headphone connection "g", through switch to headphone connection "h" ( switch is closed when headphones are inserted), to via "F", to second of two amplifier circuits (B+) in IC100 (pin 6), out pin 3 to "T", to
CC104, to "L", through L101 and L104 to headphone connector "b" and "c", and out to both headphone speakers, giving pseudo-stereo.
Note that, when the headphones are inserted, connection "g" to "f" is NOT disconnected, thus, the speaker amplifier A+ is still active. 
Therefore, the speaker circuit is still creating an amplified signal for the speaker.  But, when the headphone is inserted, the switch
between "e" and "d" is opened, thus disconnecting the signal from the speaker.

Charlie


ABBREVIATED AUDIO CIRCUIT SCHEMATIC
(http://i721.photobucket.com/albums/ww214/charliee1151/TEsch.jpg)

TE BOARD TOP VIEW
(http://i721.photobucket.com/albums/ww214/charliee1151/TETop.jpg)

TE BOARD BOTTOM VIEW
(http://i721.photobucket.com/albums/ww214/charliee1151/TEBot.jpg)
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Platinumfungi on June 06, 2009, 05:23:42 AM
Nice work Charlie  :clap: Thanks for sharing the info  :D
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: milkmanv1 on July 19, 2009, 04:26:06 PM
Oh man, thanks soooo much D-Lite, Who woulda thought changing something as simple as ONE cap,  could go from no sound, TO LOUD SOUND! Thanks so much, you saved me a buncha money (and not on my car insurance!!)
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: TheClash603 on August 27, 2009, 05:11:25 PM
Yikes, I figured the explanation to fix the problem would be "shake the unit" or something an electronic moron could fix.  Looks like I will have to stick to playing my Express with headphones...  this looks like rocket science.

My broken Twin Famicom is also crying :(
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: override on August 28, 2009, 02:50:13 AM
Yikes, I figured the explanation to fix the problem would be "shake the unit" or something an electronic moron could fix.  Looks like I will have to stick to playing my Express with headphones...  this looks like rocket science.

My broken Twin Famicom is also crying :(


I just recently posted very good pics of doing a full cap replacement - HERE (http://www.pcenginefx.com/forums/index.php?topic=5303.msg122069#msg122069), if you would like to refer to them. I can do the repair for you aswell, PM me if your interested. It would run you S/H, Parts and Labor - $35.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: ApolloBoy on January 03, 2010, 04:07:55 PM
I just fixed my new TurboExpress and I just wanted to say that you can substitute the 100uF caps with smaller ones. I used 68uF caps in mine and the sound is nice and loud. :)
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: christoph on March 09, 2010, 12:24:46 PM
So the sound and headphones were not working AT ALL on my Turbo Express and I did this mod - the sound now works in both the headphones and speakers - but its the infamous low sound. Low in both speakers and headphones. What do you recommend doing?
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: blueraven on March 09, 2010, 04:11:42 PM
Start looking around the board for capacitors that have broken or corroded legs; check for electrolytic fluid on the board. I'm guessing that you may have another bad capacitor. the 2 big 100's around the sound caps have been bad in the last 4 units I have opened up  ~ but be careful and work very slow ~ The traces love to come up in this area.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: christoph on March 10, 2010, 03:51:45 AM
100uf 35v caps will work for those right?

and I replace which ones, green or blue: (I already removed one cap in the green and replaced another with the guide)

(http://img519.imageshack.us/img519/9817/tefix2.html)

(http://img717.imageshack.us/img717/6425/tefix1.html)
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: blueraven on March 10, 2010, 08:32:37 PM
The area in green. Start there in your search.

The two tiny caps in the green area are 33uf (microfarad) capacitors - Those are the Sound Caps! Replace them first. You can upgrade them to 45uf to "Hot Rod" it for sightly louder volume.

You're getting close.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: christoph on March 11, 2010, 04:09:11 AM
Nice. I think I'm gonna upgrade it to 45uf. Thanks mate.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: blueraven on March 11, 2010, 06:44:13 AM
Correction, 47uf. No problem; Red Ghosts capacitor chart will help too, here's the link:

http://www.pcenginefx.com/forums/index.php?topic=5303.0

After staring at it for about 15 minutes, everything should start to make sense.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: christoph on March 11, 2010, 08:34:55 AM
lol

this website is so awesome
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: nat on March 11, 2010, 12:37:34 PM
Actually, all the caps circled in green are in the audio circuit, not just the small ones...
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: christoph on March 14, 2010, 08:42:26 AM
Where is the best place to buy capacitors online? My local radioshack does not have a few of these caps and there is no other local place to shop at.

:/

Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: kattare on March 14, 2010, 03:19:26 PM
I got mine in bulk from www.allelectronics.com (http://www.allelectronics.com/).  A lot of folks swear by www.digikey.com (http://www.digikey.com/).  Dunno if that helps or not.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: christoph on March 14, 2010, 07:57:38 PM
whoa

those sites are awesome

thanks
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Duo_R on March 15, 2010, 04:53:53 AM
If you replaced all caps in the audio circuit (circled green) your problem should be fixed.

So the sound and headphones were not working AT ALL on my Turbo Express and I did this mod - the sound now works in both the headphones and speakers - but its the infamous low sound. Low in both speakers and headphones. What do you recommend doing?
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: christoph on March 17, 2010, 06:54:00 PM
For anyone who was wondering where to order capacitors from - http://www.digikey.com/ - is f*cking awesome.

I ordered 40 various capacitors for $8.40 shipped. It arrived in two days. Great service.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: RoyVegas on May 27, 2010, 12:04:08 PM
Trying to pick up a few caps locally to fix the sound on my Expresses...  Will a 100 uF 35V work for the sound fix?
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: chop5 on May 27, 2010, 01:17:55 PM
thats fine roy,as long as its not under 6v from the original rating. i used a higher voltage on mine i remember cause i couldnt find 6v
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: RoyVegas on May 28, 2010, 05:57:21 AM
I've never done any soldering or repair work before but it seemed easy enough to give it a try.  Worked like a charm!  Thanks to guides and help from cool people on this forum another Express sounds good as new.  Thanks guys!
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Ichibanrei on October 08, 2010, 02:11:56 PM
Thanks a TON for this guide.  I had scored on a PC Engine GT for 25 bux locally on craigslist of all places.  The sound was out but doing this mod brought it back.  So happy!  :D
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: voidwhichbinds on November 05, 2010, 04:01:14 PM
thanks a lot for this guide - I've finally gotten around to replace that 100uF capacitor, and it's fixed my TE's very low sound issue..

but for completeness, it should be noted that the highlighted cap in the photo on page 1 is used for the left channel audio - the other 100uF cap is used for the right channel...
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: BlueBMW on November 06, 2010, 01:33:57 AM
I thought the express just had a mono speaker built in?  I guess there's probably a second circuit for the headphones port.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Charlie on November 12, 2010, 09:26:43 AM
==>I thought the express just had a mono speaker built in?  I guess there's probably a second circuit for the headphones port.<==

Sort of.  So try:
http://www.pcenginefx.com/forums/index.php?topic=702.msg116301#msg116301

Charlie
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Duo_R on January 31, 2011, 05:30:31 PM
Charlie - this isn't exactly sound related, but what kind of part is at L502?

From what I can tell this helps switch power from batteries to external wall plug. I need to replace a bad part on one of my TE units but not sure what to replace it with.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Charlie on February 07, 2011, 10:25:54 PM
I'll check.
(Sorry I missed your message)

Charlie
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Charlie on February 08, 2011, 02:06:52 AM
L501 and L502 are 1uh, .08ohm inductors on the battery input lines.  Looks like they are there for noise reduction purposes, so functionally you should be able to bypass them (short across them).  You don't even have to remove them!  However, they may have an effect on system noise performance. (But you may not care about that).  The easiest way to test that is to simply put a piece of wire in place of them, and see if you notice any negative effects, especially on the video display.

Charlie
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Duo_R on February 08, 2011, 07:53:09 PM
thanks Charlie, is there a part i can replace those with? Or should i just try to jump?
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Charlie on February 09, 2011, 12:47:51 AM
Jumping should work fine...functionally.  Just can't tell what may happen performance-wise.

If you want to find a replacement part:
1. Inductance should be ~.8uh to 1.5uh
2. Resistance should be <.12 ohms (lower = better)
3. Footprint must match size on board (DUH!)
4. Current-carrying capacity should be at least equal to that of a AA cell, more = better.
I wouldn't expect to find something that meets all these requirements, but there should be a reasonable compromise out there somewhere.

Charlie
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: thesteve on April 16, 2011, 07:30:14 PM
just a note on capacitor failures in these units.
these capacitors not abused and should not fail.
meaning the failures are from poor part quality and apply to all similar caps used in the unit.
I tested my old caps after removing and found them running @ about half their original value.

another note. my internal speaker didnt work after cap replacement due to tarnish in the headphone jack.
I disassembled the jack, cleaned and reassembled.
works great now
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: megamatt on August 01, 2011, 11:12:27 AM
hello, just wondering if anyone around here would be willing to repair my Turbo Express. i have no soldering experience and i'm afraid i would mess up my Express if i tried to fix the sound issue myself

(i know an offer is in the original post, but that was back in 2005 and i don't know if that offer stills stands. i'm a noob around these parts)
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: BlueBMW on August 01, 2011, 11:35:25 AM
hello, just wondering if anyone around here would be willing to repair my Turbo Express. i have no soldering experience and i'm afraid i would mess up my Express if i tried to fix the sound issue myself

(i know an offer is in the original post, but that was back in 2005 and i don't know if that offer stills stands. i'm a noob around these parts)

I do these repairs.  Shoot me a PM if you're interested.  I can also do a switchless region mod on it if you're interested.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: megamatt on August 04, 2011, 01:28:42 PM
hello, just wondering if anyone around here would be willing to repair my Turbo Express. i have no soldering experience and i'm afraid i would mess up my Express if i tried to fix the sound issue myself

(i know an offer is in the original post, but that was back in 2005 and i don't know if that offer stills stands. i'm a noob around these parts)

I do these repairs.  Shoot me a PM if you're interested.  I can also do a switchless region mod on it if you're interested.

PM sent, although it's not showing up in my outbox. Let me know if you got it or not
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: BlueBMW on August 04, 2011, 02:06:30 PM
Got it and replied!
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: farankoshan on September 20, 2011, 06:17:12 AM
If the sound is the only problem, should I just have the 100uF & 33uF capacitors (speaker & audio) replaced, or go and do a full cap replacement?
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: thesteve on September 20, 2011, 07:26:31 AM
considering speaker and audio seperately is a misconception.
the speaker connects to the headphone jack directly.
a full cap change will fix things you may not have noticed were degraded yet, while avoiding future failures
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: farankoshan on September 20, 2011, 07:54:03 AM
considering speaker and audio seperately is a misconception.
the speaker connects to the headphone jack directly.
a full cap change will fix things you may not have noticed were degraded yet, while avoiding future failures


I figured as much. :) Thanks for affirming the right thing to do with these old systems of ours. :)
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: farankoshan on September 20, 2011, 08:46:28 PM
I swapped all the old caps out (the 470uF 6.3v cap was especially leaky, as were the caps dedicated to audio) for new electrolytic ones, and now my PC-Engine GT is loud, clear, clean and ready for action! Thanks so much to everyone who helps out in their own way on this forum; some little bits of help go a long way for the rest of us.

Lemme know if you guys need me to post pics of how we fit the new caps in.

But for now, excuse me as I make a test run by paying King Fossil a surprise visit...
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: coyo5050 on September 28, 2011, 02:13:09 PM
I get the same hum, and im pretty sure its normal. I dont know how it is on yours, but on mine it only occurs when the volume level is pretty high. My portable dvd player does the same thing (as do a lot of electronics).
It is also possible that one of the other dry caps on the board is allowing interference to bleed into the audio. When I have time I may replace all the other caps on the board, but its no rush because it sounds normal to my ears.

Finally got around to replacing some caps on my TE, did the one for the video and it now works and replaced the 2 100 6v for the sound plus the 100 16v next to those 2. Also replaced 2 other 100 6v that looked suspect. The sound is now very loud but I am getting a hum/buzz. Is this normal? Is this the sound the quoted poster is referring too? I've never had a working TE before so nothing to compare too. Thanks!

Edit:

I notice another post talking about a 60 cycle hum and replacing the 100 6v under the metal shield I am guessing that would be the fix? I tried to get the shield off but was having a hell of a time and gave up.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: farankoshan on September 29, 2011, 06:20:31 AM
Finally got around to replacing some caps on my TE, did the one for the video and it now works and replaced the 2 100 6v for the sound plus the 100 16v next to those 2. Also replaced 2 other 100 6v that looked suspect. The sound is now very loud but I am getting a hum/buzz. Is this normal? Is this the sound the quoted poster is referring too? I've never had a working TE before so nothing to compare too. Thanks!

Edit:

I notice another post talking about a 60 cycle hum and replacing the 100 6v under the metal shield I am guessing that would be the fix? I tried to get the shield off but was having a hell of a time and gave up.

If the hum doesn't drown other sounds, I personally like it. Adds to simulate the experience of mild imperfection, as were the memories we had with this beloved system of ours.. :)
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Keith Courage on November 26, 2011, 07:22:13 AM
The hum is normal and is especially louder with an AC adapter not so much with batteries.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: jasonbar on March 02, 2012, 10:29:18 AM
Another TurboExpress resurrected! I added just the 1 capacitor detailed in the 1st post. Nice & loud. Woohoo! Thanks!

-Jason
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: v.g.lover on March 19, 2012, 07:11:18 AM
I got a broken PCE GT at a garage sale with hopes of fixing it and am happy to report that after replacing the one video cap outlined in the other guide as well as adding in the one from this guide, I now have a fully working PCE GT! Ah, portable unrated Splatterhouse, how I enjoy thee now.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: BlueBMW on March 19, 2012, 07:34:54 AM
Please please please!   If you have the thing open pleeeease do all the caps!  Its asking for trouble later on down the road!
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: ltpitt on April 19, 2012, 09:55:29 AM
Ok...

I admit: I've tried fixing my little buddy and I went from no sound to mono sound in earbuds and sound in speaker...
With a little background hum noise.

I've read that changing just the 1st capacitor of this thread could not solve the problem but it took me ages and the infinite fear to destroy my unit (I am clearly in love with it).

I've read of many forum users with a steady hand and a big heart that are willing to help their tongue-tied brothers to speak again :)

If anyone is in Europe probably's better (I live in Rome) so I can send the little baby with insurance without being forced to sell my house :)
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: 420GOAT on May 30, 2012, 10:36:16 AM
i work around the corner from radio shack and was wondering if this cap is ok to use.


http://www.radioshack.com/product/index.jsp?productId=2102484
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: thesteve on May 30, 2012, 04:08:25 PM
that will work, but is not gonna be an easy fit
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: chapel on November 01, 2012, 09:02:26 AM
rad. I just yanked my TE out and noticed my sound was a bit low...
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: Slypty on June 01, 2014, 03:10:35 PM

  Thanks for the tip, but I'm still having no luck.  I pulled a few traces from the board since it had some real heavy oxidization.  I managed to do the mod well, and repair the broken pads to their traces. 

  Still no luck.  Not sure what else could be irking it, could I have a bad Amp? 
Title: Re: BIG NEWS: Turbo Express SOUND FIX!!!!
Post by: Slypty on June 04, 2014, 01:21:41 AM
Just replacing the single cap did not work for me. In fact, it made the sound stop working alltogether. The audio opamp NEEDS all four of those caps by design, but it just so happens that the one D-lite pointed out is most crucial for operation and will fix most peoples problems (but probably not 100%).

I dont think the screen can be replaced by replacing caps. The screen takes RGB input, and from my tests the signal comes almost directly off of the hu6260. Sounds like your screen itself is bad, and unfortunatly it probably cant be fixed. Old lcds like these are just really flakey.
When I have time, I have a modern LCD from a pocket tv that I plan on hacking to take RGB, and putting that in one of my Expresses. It will be nice to have a system with modern LCD.


  Thanks for posting that part, I had done this mod and still have no sound.  I'm guessing broken trace somewhere, it's getting really frustrating.  I have the recommended Cap attached to the Op Amp, and the other one with equal Capacitance has a stripped trace pad.

  A quick question:  Would it be possible to attach BOTH Caps to the Op Amp?  Basically just to make a quick test to see that things are working?   I know there's 4 Caps but the one's that seem the most iffy on my end are the bigger one's.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: thesteve on July 02, 2014, 05:56:53 PM
try the headset
if that works stop messing with the amp/caps
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: mamejay on August 02, 2014, 11:41:20 PM
Hi thesteve,
I have just recapped my friends one but still no audio at all from internal speaker.  I do get audio from the headphones.  There was some damage to the tracks on one of the caps.  Its the 100uf right next to headphone jack.
I traced the positive to pin 4 of a chip on the backside of the board and the negative just went to negative.
Any idea's about why no audio would be coming out or if there is something else I can try?
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: thesteve on August 03, 2014, 02:51:29 PM
the speaker hooks to the headset jack directly
the jack jumpers the speaker on when no jack inserted
the jack could be just dirty
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: mamejay on August 03, 2014, 10:37:54 PM
the speaker hooks to the headset jack directly
the jack jumpers the speaker on when no jack inserted
the jack could be just dirty
Thanks for that.  Can I possibly put a solder jumper to force the external speaker to work?  Just to confirm it is the headphone jack.

EDIT:
I bridged the points that are shown in page 1 of this thread and now I can get audio out of the speaker!!  So looks like it could be the headphone jack connector.  Any tips on cleaning that up or even a replacement that can be used?

EDIT once again:
More investigation has shown that the little gate inside the headphone jack is broken.  Now comes the tricky part.  Is there a replacement for one of these?  I have external audio now at least but would be good to get it back to fully working.
Title: Re: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: thesteve on August 04, 2014, 05:51:19 AM
It wa not an uncommon jack BITD, so it should be available
Title: REPAIR GUIDE - TurboExpress: Sound Fix
Post by: mamejay on August 04, 2014, 10:38:16 AM

Thanks for that.  Well if anyone has something please let me know.  I will keep an eye out for one.  I found one for sale on a retro website but I think the shipping for such a little thing will be a killer to Australia.