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NEC TG-16/TE/TurboDuo => TG-16/TE/TurboDuo Sales & Trades => Topic started by: lastcallhall on January 10, 2012, 05:44:48 AM
Title: Where can I tap a sync signal for s-video?
Post by: lastcallhall on January 10, 2012, 05:44:48 AM
Please bear w/ me - I'm currently one handed and on a lot of pain meds coming out of shoulder surgery...
Last week I decided to build a s-video/composite circuit out of a CXA1645 like I've done at least a dozen times before, only this time I planned on sticking it into a TG-16. I built the circuit, attached the RGB IN locations on the chip to the RGB OUT locations on the TG-16 EXT connector (23A, 23B, and 23C), along with the SYNC IN on the chip to the SYNC OUT on C22. everything is properly attached to their respective components and grounded. In addition, I tapped the Audio from 1A and 1C, and grounded them to the board, as well. There's also a reset button and region chip installed, as well. I powered the console on in s-video and I get audio just fine but no sync on s-video. I try it with composite, same thing. I test it with my turbo booster and I get good video and audio. So, I figure my problem is with the sync pin. After some researching I find that it's actually labeled composite sync, but that shouldn't make a difference, right? Sync should be sync, as far as I understand it. I'm hesitant to take the system apart again, now that everything is soldered and screwed into place, so is there anywhere on the bottom surface of the board that I can tap into?
Thanks!!!
Title: Re: Where can I tap a sync signal for s-video?
Post by: SignOfZeta on January 10, 2012, 08:28:04 AM
The only thing you can get from a PCE is composite sync, and it's not the best example of composite sync out there. If it doesn't work for you...sorry, I have no advice as I've had nothing but trouble with it.
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on January 10, 2012, 10:23:51 AM
Hm. Ok, thanks for the info. I think i'm going to try and tap directly off of the C6260A and see what happens...
Title: Re: Where can I tap a sync signal for s-video?
Post by: ogre on January 10, 2012, 03:19:44 PM
To get a good sync for the CXA use a LM1881N. Put the composite video through this circuit and it will output composite sync.http://www.national.com/images/pf/LM1881/00915001.pdf (http://www.national.com/images/pf/LM1881/00915001.pdf) This is needed as the systems own c-sync does not put out a useable signal.
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on January 11, 2012, 01:55:42 AM
To get a good sync for the CXA use a LM1881N. Put the composite video through this circuit and it will output composite sync.http://www.national.com/images/pf/LM1881/00915001.pdf (http://www.national.com/images/pf/LM1881/00915001.pdf) This is needed as the systems own c-sync does not put out a useable signal.
Fantastic, thanks!
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on January 11, 2012, 06:18:12 AM
So does this mean by using the said IC and using that signal along with the typical RGB outs you can run it to an S-Video connection? I have also been wondering how to do this myself for a while now.
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on January 11, 2012, 11:14:29 AM
That's what I'm hoping for... :)
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on January 15, 2012, 08:51:08 AM
So, I have a quick question: I understand the schematic except for the RSET pin. What is it, and what is it used for? More importantly, do I need this pin for what I want to accomplish? Thanks!
Title: Re: Where can I tap a sync signal for s-video?
Post by: bust3dstr8 on January 15, 2012, 08:55:06 AM
Rset=Reset
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on January 15, 2012, 09:44:52 AM
That's what I thought, but I never assume anything in electronics, LOL. :)
Also, I was looking through the data sheet and saw that there's an application circuit diagram below the connection diagram. I'm thinking I should use the app circuit instead of the connection circuit?
Title: Re: Where can I tap a sync signal for s-video?
Post by: grahf on January 16, 2012, 02:16:11 AM
The connection diagram on page 2 is all you need. I used this chip for my Svideo boards I was making a few years ago. Also, you didn't mention anything about the 3.579 MHz frequency input the CXA1645 needs. I guess you picked up an oscillator? If you don't have that hooked up the circuit won't work. They are available in half size dip packages, like this:
The connection diagram on page 2 is all you need. I used this chip for my Svideo boards I was making a few years ago. Also, you didn't mention anything about the 3.579 MHz frequency input the CXA1645 needs. I guess you picked up an oscillator? If you don't have that hooked up the circuit won't work. They are available in half size dip packages, like this:
Thanks for clearing the diagram up - I was going crazy trying to find a bi-polar 510pF capacitor. :)
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on January 31, 2012, 09:11:04 AM
An update...
This is crossposted from Sega-16.com, so I apologize in advance for any repeats in information.
Long and short of it is, is that I bought a Duo-R a couple months back to replace my TG-16/Turbobooster combo I've had for a little over a year. Well, the Duo is in need of a CD lens replacement, so in the mean time I thought I'd try and mod the TG-16 for s-video and audio out, and see what comes of it. I was able to look at the documentation shown over at GameSX.com (http://), and from there took the proper signals and fed them into the CXA chip, composite signal included, on top of adding a region chip (Obey chip from BlueBMW and TheSteve from pcenginefx) and reset button. Once I had everything hooked up, I powered it on and got this:
As you can see, the sync signal seems to be trashed. I've done a little research and found the following:
1) The sync signal from C23 on the EXT port is labeled composite sync, as is pin 44 on the 6260 CPU of the TG-16 2) Knowing this, I purchased a LM1881 Video sync seperator, and fed the a) the composite signal from the EXT port, b) the composite sync signal from the EXT port, and c) the composite sync signal from the 6260 into the chip (all at different times, obviously), hoping to get a clean sync signal out of any one of them, but no such luck. This was actually suggested by someone over on the PCEFX forums. 3) I have several 4558D OP AMPs lying around from an earlier CCAM mod attempt, but I'm not sure if I can use them to amplify this type of signal. even so, I don't have the slightest clue as to how to get it done.
I'd really like to get this up and running (and sold...), but I seem to have hit a wall on this. I'm half tempted to take it to school so I can look at it all in a lab with proper test equipment, but if I could solve it prior to that, it would be even better. So what do you all think? Any help is always appreciated. Thanks!
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on January 31, 2012, 10:59:47 AM
the 4558 is way too slow (tried it) a transistor amp can be built that works well. the 1881 also works, but must have a capacitor input, duo to the offset in the chip
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on January 31, 2012, 02:54:14 PM
the 4558 is way too slow (tried it) a transistor amp can be built that works well. the 1881 also works, but must have a capacitor input, duo to the offset in the chip
Hm. I put a 0.1uF cap on the 1881 composite pin and it didn't change anything.
I think tomorrow or sometime soon, I'm going to rebuild the circuit from scratch. This can't be that complicated.
I just hate having to undo everything and start all over again... >=(
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 01, 2012, 06:06:38 AM
a good way to confirm the sync sig is to hook it to a tv. the tv will see the sync as a black picture (not rolling)
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 01, 2012, 09:39:09 AM
a good way to confirm the sync sig is to hook it to a tv. the tv will see the sync as a black picture (not rolling)
So, here's what I did, and my observations:
I took the csync signal from the 6260 and added it to the composite out jack on the system and the image stabilized, albeit in B/W, which leads me to believe that the sync signal is good on the system, I just need to rework the CXA1645 circuit - something must have gotten messed up somewhere.
Parent/teacher conferences tonight, so I doubt I'll get to this until morning, but I'll figure it out...
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 01, 2012, 04:17:53 PM
the 1645 needs the sync to be TTL levels (0 to 5V switching) you have about 180mV off the chip
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 01, 2012, 04:42:52 PM
I'm kinda lost right now and not sure which way to go.
I'd appreciate the help. :)
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 01, 2012, 09:04:50 PM
nope that circuit wont work at all
Title: Re: Where can I tap a sync signal for s-video?
Post by: SignOfZeta on February 01, 2012, 09:29:33 PM
OK, seriously, there are a lot of s-video modded Duos out there. Someone must know how to do it.
Also, my question got buried back there: will a Neobitz work directly from the Hu chip or do I need something else? I also have a JRok.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 01, 2012, 10:22:14 PM
ok i dont know anything about neobits...........checking......................nope not enough info on the jrok.
most have used the 1881 sync stripper on the composite output. the TE uses a common emitter transistor amp, which causes +sync of TTL levels. the best way is comp sync from the chip--->common emitter transistor amp----->logic inverter------>encoder ic
Title: Re: Where can I tap a sync signal for s-video?
Post by: grahf on February 01, 2012, 10:57:36 PM
SignOfZeta, I've always heard that the JRok kits don't work for whatever reason, and the guy who makes them doesn't know why. Never tried one myself, though. I have no idea about the Neobitz.
lastcallhall, seriously, stop jumping around all kinds of hoops and just go with the LM1881. It's pretty much the standard way to do this, and it works. Everyone uses it for everything. Here is a picture of a circuit from the gamesx page:
Original link: http://www.gamesx.com/misctech/lm1881.htm (http://www.gamesx.com/grafx/lm1881.gif)
It's incredibly easy, and you only need like 50 cents worth of components. You are ONLY going to use pins 1, 2, 4, 6 & 8.
Composite out is pin 1, which is what you're after. This goes into your CXA1645.
Composite Video goes into pin 2, NOT composite sync from the HU6260. The easiest place to get composite video is off the back of the original AV out plug. Just solder a wire to the right place on the inside of your Duo. You need to put an 0.1uf capacitor in-line, which looks like this: http://www.newpages2u.com/images/12882347761ef4fa1d3bb9fa56b4ee022142f88ecc.jpg and will say "104" on it.
Pin 4 goes to ground. Make sure the LM1881 and your CXA1645 circuit share the same ground. The grounds for everything should end up connected to the ground on your Duo's motherboard.
Pin 6 is the "set" pin. Not reset. You need another 0.1uf capacitor, the same one as above. You also need a 680kohm resistor. Make sure the value is correct. You hook both of these parts to pin 6, then the other side of them goes to ground. The same ground as everything else.
Pin 7 is 5v input. You can use any value up to 12v, but it's easy enough to get 5v off of the Duo motherboard, and I personally use 5v.
Good luck, and if this still doesn't work please post pictures of what you have currently made.
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 02, 2012, 07:51:25 AM
SignOfZeta, I've always heard that the JRok kits don't work for whatever reason, and the guy who makes them doesn't know why. Never tried one myself, though. I have no idea about the Neobitz.
lastcallhall, seriously, stop jumping around all kinds of hoops and just go with the LM1881. It's pretty much the standard way to do this, and it works. Everyone uses it for everything. Here is a picture of a circuit from the gamesx page:
Original link: http://www.gamesx.com/misctech/lm1881.htm (http://www.gamesx.com/grafx/lm1881.gif)
It's incredibly easy, and you only need like 50 cents worth of components. You are ONLY going to use pins 1, 2, 4, 6 & 8.
Composite out is pin 1, which is what you're after. This goes into your CXA1645.
Composite Video goes into pin 2, NOT composite sync from the HU6260. The easiest place to get composite video is off the back of the original AV out plug. Just solder a wire to the right place on the inside of your Duo. You need to put an 0.1uf capacitor in-line, which looks like this: http://www.newpages2u.com/images/12882347761ef4fa1d3bb9fa56b4ee022142f88ecc.jpg and will say "104" on it.
Pin 4 goes to ground. Make sure the LM1881 and your CXA1645 circuit share the same ground. The grounds for everything should end up connected to the ground on your Duo's motherboard.
Pin 6 is the "set" pin. Not reset. You need another 0.1uf capacitor, the same one as above. You also need a 680kohm resistor. Make sure the value is correct. You hook both of these parts to pin 6, then the other side of them goes to ground. The same ground as everything else.
Pin 7 is 5v input. You can use any value up to 12v, but it's easy enough to get 5v off of the Duo motherboard, and I personally use 5v.
Good luck, and if this still doesn't work please post pictures of what you have currently made.
Good deal, that sounds workable. Thanks!
Quick question, though - I'm doing this on an american TG-16, not my Duo. Would the video signal from VIDEO A23 on the EXP port suffice for pin 2 on the LM 1881?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 02, 2012, 08:28:00 AM
yes
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 02, 2012, 09:32:17 AM
:?
Still didn't work.
Here are some closeups of what I'm looking at:
Here's the LM1881. Solid green is video in from pin A23 on the EXP port, striped green is sync out, solid blue is 5V in and the two striped blue are tied together and are connected to ground. (http://pic.photobucket.com/bwe.png)
Here's a shot of the voltage regulator. You can see the striped blue wire coming from the LM1881 to the center pin which is ground, along with another ground wire from the CXA1645, as well as the solid blue 5V wire from the LM1881, and the 5V line from the CXA1645 (Will show shortly) connected to voltage out, which should supply a 5V voltage to all components. (http://pic.photobucket.com/bwe.png)
Here's the CXA1645 itself. Pin 1 is grounded, pins 2,3,&4 are RGB respectively, pin 5 is No Connection, pin 6 is connected to pin 3 of the oscillator (shown above the IC), pins 7, 12, & 19 are all tied together, and fed into pin 4 of the oscillator, which is connected to the voltage out on the regulator (shown in the previous pic). Pin 8 is no connection, pin 9 is grounded, and pin 10 is sync in. Pin 11 is no connection. (http://pic.photobucket.com/bwe.png)
Bottom half of the 1645. Pin 13 is connected to a 47KOhm resistor and a 0.1uF capacitor, which are then each ran to ground. Pin 14 is connected to a 10uF capacitor connected to ground, while pins 15 and 16 are connected to a 75ohm resistor and a 220uF capacitor in series each, connected to chroma and luma respectively. Pin 17 has no connection. Pin 18 is connected to a 20kohm resistor out to ground. Pin 19 has been discussed earlier, pin 20 is also connected by a 75ohm resistor and 220uF capacitor in series out to composite out. Pins 21, 22, & 23 are not used for this circuit. Pin 24 is connected to ground. (http://pic.photobucket.com/bwe.png)
Here's a shot of the ground wires all bundled together and fed into a single wire for organization's sake (note: my finger is on the composite out wire; the striped orange wire ABOVE my finger is connected to the bundle of wires running to ground: (http://pic.photobucket.com/bwe.png)
So... here we are.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 02, 2012, 11:09:05 AM
check if the output from the 1881 chip will give a raster (sync no-pic) on your monitor. another note when you have multiple grounds tie them together at the chip
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 02, 2012, 11:19:30 AM
check if the output from the 1881 chip will give a raster (sync no-pic) on your monitor. another note when you have multiple grounds tie them together at the chip
OK, I'll take a look shortly, thanks. :) Also, I tied together several groups of ground @ the chip - there's something like 12 grounds on the unit and I got them down to four before tying them up to one on the way out...
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 02, 2012, 02:02:06 PM
you really want the grounds tied as close to the chip as possible, as you can see in this pic i have them jumpered across the chip. (http://pcengine.freeforums.org/download/file.php?id=21)
BTW that chip outputs composite and S-Video
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 02, 2012, 03:07:52 PM
No raster signal when the output is applied directly to the composite out - it still flickers.
I even pulled the video signal from A23 on the EXP port and fed it straight to the composite out - no change.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 02, 2012, 10:22:21 PM
i just pulled S-vid strait off the huc6260. i needed to amp the Y output and filter C out of composite
Title: Re: Where can I tap a sync signal for s-video?
Post by: grahf on February 03, 2012, 01:54:37 AM
No raster signal when the output is applied directly to the composite out - it still flickers.
I even pulled the video signal from A23 on the EXP port and fed it straight to the composite out - no change.
lastcallhall, your descriptions of what you have going to each pin looks good. I compared it with the CXA1645 datasheet, and everything is right. The only possibility is that one of your chips is fried, which isn't that likely, or you mixed up a wire somewhere. You said you were getting composite video signal off of pin A23 on the expansion port. That's the wrong pin. Composite video is on pin A22. See this for the pinout: http://www.gamesx.com/misctech/pcebp.php
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 03, 2012, 04:08:45 AM
ya could go simple, and just pull S-Video right off the huc6260 (http://pcengine.freeforums.org/download/file.php?id=28) the cap is 0.001uf the transistor i tested with is an S9013 40 is pin 40 of the huc6260 comp is anywhere you can get composite video (I tapped the vid pin on the RF modulator)
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 03, 2012, 04:32:23 AM
No raster signal when the output is applied directly to the composite out - it still flickers.
I even pulled the video signal from A23 on the EXP port and fed it straight to the composite out - no change.
lastcallhall, your descriptions of what you have going to each pin looks good. I compared it with the CXA1645 datasheet, and everything is right. The only possibility is that one of your chips is fried, which isn't that likely, or you mixed up a wire somewhere. You said you were getting composite video signal off of pin A23 on the expansion port. That's the wrong pin. Composite video is on pin A22. See this for the pinout: http://www.gamesx.com/misctech/pcebp.php
Oh, crap.
Someone on the Sega-16 forums said that something was probably overlooked. I'm tapping into the wrong signal from the EXP port...
I'll play with it now and see what I can do.
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 03, 2012, 05:17:31 AM
OK, it still doesn't work, but I have it narrowed down to the chip...
From another member on Sega-16, I constructed this circuit prior to running the composite signal into the LM1881:
I purposely left the leg on the 10k resistor connected to composite uncut and when I connected it directly to the composite out, it stabilizes the picture, but the colors are all out of wack. I tried to take a picture and video, but it doesn't come out the way I see it in person. Anyway, I'm fairly sure that the CXA chip is the culprit, as I can get a solid sync signal from the EXP port, the C6260, and from the composite out on the EXP port, as well. So, what I'm going to do is I'm going to order a new CXA1645 from a stateside dealer and just redo the entire circuit. This may take some time, so I'll check back in once I get that done.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 03, 2012, 05:51:30 AM
skip it, you dont need an encoder, as the TG16 outputs S-Vid almost native. you will need a driver amp for the Y (luminance) and an isolation cap for the C (chroma) see simple schematic above
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 03, 2012, 07:18:55 AM
What the hell, I'll give it a shot. :)
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on February 03, 2012, 07:50:24 AM
Let me know how it goes, I'd love to give that mod a shot if it works!
Will do. Looks like I'm going to have to order the S9013 - All I have are 2SC945 and 2N3904 transistors lying around (unless one of those will work, but I'm guessing not).
Off to Digikey...
Also, @ TheSteve: which pin did you tap into on the RF modulator for video? I took my modulator off to make room for the other mods. Thanks!
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on February 03, 2012, 08:21:17 AM
Looks like I'm going to have to order the S9013 - All I have are 2SC945 and 2N3904 transistors lying around (unless one of those will work, but I'm guessing not).
You could try a 2N3904, it's an NPN transistor like the S9013 is and it usually comes up as an S9013 substitute.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 03, 2012, 08:53:49 AM
any npn should work fine rf mod pin2
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 03, 2012, 09:21:40 AM
It works! None of that fancy encoder stuff, you can pull it right off of the chip! As soon as I find my video capture card, I'll toss up some comparison pics. However, I can't tell if the chroma signal looks slightly washed out, or if that's just the way the games are meant to be seen. Either way, I'm sure there's a method to adjust it. :)
Thank you all so much!
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 03, 2012, 12:33:21 PM
the picture intensity can be adjusted by changing the resistor value (less resistance= brighter picture) the transistor chosen will effect contrast just a little.
Title: Re: Where can I tap a sync signal for s-video?
Post by: grahf on February 03, 2012, 01:58:33 PM
That's pretty cool, I've never heard of that before now. I'm really interested in seeing how it looks.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 03, 2012, 02:45:47 PM
i tested it on 2 monitors last nite using a 47ohm resistor. 1 was perfect, the other a bit clipped. they both looked good, just my Y signal was super hot (too much for 1 of the displays) the 100 was somewhat a guess.
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on February 03, 2012, 02:53:49 PM
What would the signal be like with a 75 ohm resistor?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 03, 2012, 03:07:01 PM
solid, might be too hot depending on the transistor
Title: Re: Where can I tap a sync signal for s-video?
Post by: Bonknuts on February 04, 2012, 05:35:27 AM
ya could go simple, and just pull S-Video right off the huc6260 (http://pcengine.freeforums.org/download/file.php?id=28) the cap is 0.001uf the transistor i tested with is an S9013 40 is pin 40 of the huc6260 comp is anywhere you can get composite video (I tapped the vid pin on the RF modulator)
Yeah, but C(chroma) line isn't clean. Some svideo input displays *might* have a problem with it (one TV I had was quite touchy about svideo spec. It wouldn't see chroma for SNES Y/C. It came out B/W). Why not just tap pins 20, 26, 33 directly and build the amp circuit for that, for C?
lastcallhall: If I give you an ISO, can you burnt it and test/capture the screen for me?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 04, 2012, 10:46:55 AM
yes the chroma could be cleaner (its from pin 20 inverted) the cap cleans the signal (smaller cap cleans it more) i just used a cap and transistor i had handy
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 04, 2012, 02:52:08 PM
Yeah, but C(chroma) line isn't clean. Some svideo input displays *might* have a problem with it (one TV I had was quite touchy about svideo spec. It wouldn't see chroma for SNES Y/C. It came out B/W). Why not just tap pins 20, 26, 33 directly and build the amp circuit for that, for C?
lastcallhall: If I give you an ISO, can you burnt it and test/capture the screen for me?
This isn't for my Duo-R, this is for my TG-16. My Duo-R doesn't read burnt discs anyway... :(
EDIT: Is there somewhere I can see the C6260 pin values?
Title: Re: Where can I tap a sync signal for s-video?
Post by: Bonknuts on February 04, 2012, 04:11:04 PM
Yeah, but C(chroma) line isn't clean. Some svideo input displays *might* have a problem with it (one TV I had was quite touchy about svideo spec. It wouldn't see chroma for SNES Y/C. It came out B/W). Why not just tap pins 20, 26, 33 directly and build the amp circuit for that, for C?
lastcallhall: If I give you an ISO, can you burnt it and test/capture the screen for me?
This isn't for my Duo-R, this is for my TG-16. My Duo-R doesn't read burnt discs anyway... :(
EDIT: Is there somewhere I can see the C6260 pin values?
http://i1216.photobucket.com/albums/dd379/PCGenjin/cvbs.png?t=1295176022 (http://pic.photobucket.com/bwe64ad.png?t=1295176022) (the resistor values are somewhat off because I measured them in circuit - yeah, yeah :P ) Your Chroma line has both Y and CB on it, when it should only be R-Y and B-Y. Some svideo receivers will probably just remove *everything* with a notch filter. Remember, Chroma is still a 3.58mhz signal - or rather it's supposed to be. Some TVs and NTSC input devices might share common lines/inputs and it could through off detection logic. I know my capture card has a separate plug for svideo, but if there is CB on the Y line on the input - then it just treats the whole thing as Composite and ignores Chroma line decoding (and vice versa. Remove CB, it removes the filter circuit for Y which gives a much sharper image - allowing you to see the chroma dot pattern interference on Y). Your setup doesn't have CB on Y, but that doesn't mean it won't throw off other redundant checks on the svideo input of the device (and either disable it or give weird results).
Title: Re: Where can I tap a sync signal for s-video?
Post by: nat on February 04, 2012, 04:41:18 PM
This is a great thread.
In the past, I built an encoder based on (I think) grahf's design for SVIDEO output mods and it seemed to work OK.
I'm going to have to give steve's more direct approach a shot and see where it gets me. It seems.... Too easy.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Bonknuts on February 04, 2012, 04:45:12 PM
Hmm, looks like I was wrong. I mean, you need CB on Chroma line besides the other two - just not Y. Was just looking through old notes: http://forum.fobby.net/index.php?t=msg&goto=941& (also, the real values for the resistors are there)
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 04, 2012, 07:28:00 PM
the way i did it the Y is clean (I checked) as 3.5Mhz is higher than your clock i was able to greatly reduce its Y content through a simple capacitor. using 2 op-amps to invert and amplify the C and just buffer the Y would provide a better signal.
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 05, 2012, 08:21:19 AM
Some comparison photos. S-video is on the left, composite (pulled from A23) is on the right:
(http://pic.photobucket.com/bwe.png)
(http://pic.photobucket.com/bwe.png)
(http://pic.photobucket.com/bwe.png)
(http://pic.photobucket.com/bwe.png)
(http://pic.photobucket.com/bwe.png)
(http://pic.photobucket.com/bwe.png)
(This one I may have picked a different court between the two) (http://pic.photobucket.com/bwe.png)
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on February 05, 2012, 08:25:10 AM
Looks pretty good, do you have higher res screencaps?
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 05, 2012, 08:31:54 AM
Photobucket resized the images, and they're too big to upload on here. If you know of a working file hosting site I'll up them there.
all the info is in a post above. (post 34) thats how LastCallHall was able to do it
What he said. :D
Really, credit for this goes to thesteve, as he was the one who provided the info; I just had the system to use as a guinea pig.
Also, @thesteve: if you look at the comparison photos, especially the download package I linked to, you can see some noise when using composite. I just ran the composite signal straight from the EXP port; do you think if I placed a cap in series with the signal it would clean that up?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 05, 2012, 05:38:22 PM
i had a TG16 on the bench for region mod so i tested some signals and built it. the reason i was thinking on the subject was this thread. i just installed it in my DUO and used a 75ohm resistor.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 05, 2012, 06:08:27 PM
one of the high res pics (http://pcengine.freeforums.org/download/file.php?id=30)
Title: Re: Where can I tap a sync signal for s-video?
Post by: SignOfZeta on February 05, 2012, 08:29:02 PM
These look to be taken from a capture card. Is all that jpeg compression noise coming from there, or can you reduce that somehow?
Title: Re: Where can I tap a sync signal for s-video?
Post by: SignOfZeta on February 05, 2012, 08:30:29 PM
ya could go simple, and just pull S-Video right off the huc6260 (http://pcengine.freeforums.org/download/file.php?id=28) the cap is 0.001uf the transistor i tested with is an S9013 40 is pin 40 of the huc6260 comp is anywhere you can get composite video (I tapped the vid pin on the RF modulator)
Wait...that's it?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 05, 2012, 08:46:39 PM
thats it 3 parts
Title: Re: Where can I tap a sync signal for s-video?
Post by: SignOfZeta on February 05, 2012, 08:55:38 PM
So the Hu6220 outputs a luma signal, but not a desecrate chroma signal. Is this common? I assume I would get better results with a RGB to s-video encoder like a NeoBitz (if I could actually get the f*cker to work, which I'm sure I couldn't)?
Anyway, I guess I'll try this soon.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 05, 2012, 08:58:50 PM
the chroma signal is there too it just requires another amp (inverting) from pin 20. the best way is to use a high speed op-amp 2 channel for luma and chroma
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 05, 2012, 09:07:46 PM
the neobits is less than perfect too, due to the sync offset. the 6260 sync is delayed for final mix, causing it to not properly align with the RGB signals
Title: Re: Where can I tap a sync signal for s-video?
Post by: Bonknuts on February 06, 2012, 03:14:47 AM
So the Hu6220 outputs a luma signal, but not a desecrate chroma signal. Is this common?
Didn't see the links I posted earlier? Here (http://forum.fobby.net/index.php?t=msg&goto=1744&) and here (http://pic.photobucket.com/bwe64ad.png?t=1295176022). Not only does it output a clean chroma signal, it actually outputs both separate color components. The final step of the quadrature amplitude modulation to make C is done in the analog circuit (two lines are tied together). All VCE chip models for the PCE console systems have this (there are two revisions). I've never taken apart the portable PCEs, but I've been told they use the same VCE (huc6260) chips as well.
It outputs 4 lines: Y + sync, Color burst (the reference signal for chroma), R-Y and B-Y.
Quote
I assume I would get better results with a RGB to s-video encoder like a NeoBitz (if I could actually get the f*cker to work, which I'm sure I couldn't)?
This method gets you the same custom/unique color space that the PCE always had, just nice and clean. RGB out on the PCE has a different color space. If you care about real PCE colors, this would be the way to go IMO.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 06, 2012, 03:56:34 AM
thats an odd configuration, as the Cb,Cr is interleaved in the chip (even if mixed externally) all 4 signals come out inverted and are fed in to an inverting amp and then a buffer/driver
Title: Re: Where can I tap a sync signal for s-video?
Post by: Bonknuts on February 06, 2012, 04:38:57 AM
Now all you need to do is separate Y from sync on the Y+sync line, scale Y down my 92.5% then shift it back up into place (IRE 7.5). Then you'd have true brightness scaling that the Japanese experienced with their NTSC TVs and Japanese consoles. :wink:
They didn't bother fixing the IRE 0 vs IRE 7.5 issue when they brought out the TG16 and Duo. What does it mean? Makes the brightness of the all the colors closer together, rather than spaced apart. They blend a little better in relation to each other. Of course, that would be over the top or best of the best mod setups. Doubt people are really that ana.. err picky.
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 06, 2012, 05:12:59 AM
These look to be taken from a capture card. Is all that jpeg compression noise coming from there, or can you reduce that somehow?
They are indeed taken from a capture card. But notice the noise on the composite side over the s-video - that makes me think you can clean the composite signal up a bit. I'm out of parts for this stuff ATM, so I'll be submitting an order to digikey shortly to get everything I need to test this out a bit more.
RE: Cleaning and inverting pure Y/C - That would still be a relatively small circuit to construct, no? I wonder how much better the signal would look, and if it's worth it.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 06, 2012, 05:27:25 AM
it would depend on the monitor on some you will get a color mark on hard lum transitions white to black black to white ect, others wont see it at all. the simplest way is a 2 channel video op amp
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on February 07, 2012, 07:37:41 AM
Awesome info, I will be trying this out myself at some point once I buy the needed materials.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 07, 2012, 11:01:30 AM
if you have any scrap boards around you have the parts
my next task is composite from the express (without an encoder) I have lum now
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on February 14, 2012, 04:29:19 PM
Pardon me for being stupid but I don't quite understand the diagram. What is pin 40 and what does it do? Which pins on the transistor get wired up and where to? Also, what is the part marked with a 100 coming off of the transistor?
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on February 14, 2012, 05:16:54 PM
Pardon me for being stupid but I don't quite understand the diagram. What is pin 40 and what does it do? Which pins on the resistor get wired up and where to? Also, what is the part marked with a 100 coming off of the transistor?
Pin 40 is luma (brightness) on the HuC6260 chip. On the transistor (not a resistor), assuming it's a standard 2N3904, you wire up the middle pin (base) to pin 40 on the HuC6260, the left pin (emitter) goes to a 100 ohm resistor and then to the luma pin on your S-video jack, and the right pin (collector) goes to 5V, which can be found on the HuCard slot or various other places on the board.
For chroma (color), take the composite video signal, wire it up to a 0.001 uF ceramic cap, and the other end goes to the chroma pin on the S-video jack.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on February 14, 2012, 06:43:13 PM
Thank you very much. That makes a lot more sense. I was looking around the internet trying to figure out what the hell pin 40 did. So does this mean no video amplification of any kind will be needed for this to work or does it still output a week signal?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 14, 2012, 07:02:25 PM
the transistor is your video amp for pin 40 your taping chroma from amplified composite, so no amp needed
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on February 14, 2012, 07:53:50 PM
Quite the badass setup. Thanks for the help. I'll get around to doing this on my duo-r in the next couple days I hope.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on February 21, 2012, 03:26:06 PM
So both the composite sync and pin 47 from the RGB go to the same pin on the S-video jack? Maybe I am just confused as to where the RGB signals go?
Title: Re: Where can I tap a sync signal for s-video?
Post by: SignOfZeta on February 21, 2012, 04:37:39 PM
You aren't using the RGB signals.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on February 21, 2012, 04:42:39 PM
Ha yeah, I just figured that out. I just spoke with the steve. I was looking at the completely wrong diagram online. http://jrok.com/hardware/RGB_diagrams/video_output_wiring_v31.jpg
I got it all wired up nicely now. Even made a nice mounting place for it on my DUO-r. Thanks again steve.
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 23, 2012, 10:14:06 AM
Ha yeah, I just figured that out. I just spoke with the steve. I was looking at the completely wrong diagram online. http://jrok.com/hardware/RGB_diagrams/video_output_wiring_v31.jpg
I got it all wired up nicely now. Even made a nice mounting place for it on my DUO-r. Thanks again steve.
Where did you put yours? I've been looking over my Duo-R and can't decide on a location.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on February 23, 2012, 06:52:47 PM
I mounted it directly next to the din5 port on the rear. I am not at home right now to be able to take a pic but here is an older pic of my system. RED is where I mounted the S-video jack. It makes it real easy having it there cause you can tap composite and the 5V right from the Din 5 port. I actually mounted mine right to the plastic with some glue and one screw for the hole in my s-video jack. I didn't actually solder it to the board. However, in the future I might consider soldering the grounds to the board since that spot on the board has a large area of ground to scrape free. It's almost like the system was setup for that spot to take an S-video jack in the first place cause it is the perfect size. Alternatively you could use a Din 8 connector instead of a din 5(standard DUOs already have them) and wire it up to the other non used pins much like an RGB mod. Then make yourself a Din 8 AV cable with S-Video and AV on it. This method would take much more time not to mention the need for always having to have your specially made AV cable to use it. (http://img403.imageshack.us/img403/7793/cimg6384stuff.html) (http://imageshack.us/photo/my-images/403/cimg6384stuff.jpg/)
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on February 24, 2012, 04:14:54 AM
there's mine (http://pcengine.freeforums.org/download/file.php?id=36) right next to my RGsB
Title: Re: Where can I tap a sync signal for s-video?
Post by: lastcallhall on February 24, 2012, 07:35:42 AM
Awesome, thanks for the suggestions!
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on February 24, 2012, 11:02:57 AM
The S-video I have looked good but was way to bright compared to the original composite. Meaning the colors don't look as good in my opinion being so bright. Since I had already bought myself a 5 pack of resistors I wired up a 2nd 100ohm resistor in series with the first one and it fixed it. The video looks awesome now. So I suppose if anyone else is thinking about doing this you might want to consider using a 200ohm resister instead of 75 or 100. Oh and here are some updated pics of where I mounted it. Because of where I mounted the jack I had to break off one mounting pole from the case lid. The mounted pole isn't an important one since no screws go inside of it and nothing goes around it. So if you don't have an 8pdt switch in your system then it might be better to put the S-video jack on the other side so you won't have to do any case modifying. (http://img17.imageshack.us/img17/5020/cimg6508m.html) (http://imageshack.us/photo/my-images/17/cimg6508m.jpg/)
as i said your resistance will vary depending on the transistor used
Yep, I had also wanted to test the signal with 220 or 330 ohms to see the difference. Thanks to Keith Courage for testing out the 200 ohm range. Still, I may get a variable resistor to play with the color a bit without having to destroy the circuit every time.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on March 05, 2012, 06:39:54 PM
I was wondering if anyone else has experienced this and if maybe there is a solution. On some TVs I notices wavy lines going across the screen with my S-video. It looks like what happens when you have ground interference. Could I maybe have a bad ground inside the system? I tapped my ground right off of the bottom metal plate. Is it maybe a bad s-video cable?
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on March 05, 2012, 07:21:44 PM
I was wondering if anyone else has experienced this and if maybe there is a solution. On some TVs I notices wavy lines going across the screen with my S-video. It looks like what happens when you have ground interference. Could I maybe have a bad ground inside the system? I tapped my ground right off of the bottom metal plate. Is it maybe a bad s-video cable?
Try moving your ground to a ground point on the motherboard itself and if that doesn't work, try a different cable.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on March 05, 2012, 07:25:57 PM
you need to tap your ground from the board, not the plate. you could have a bad cable as well, but because this method uses a current controlled sig, not voltage controlled it should be less suseptable to cable issues causing noise (open cable= no pic)
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on March 05, 2012, 08:29:28 PM
Well, I soldered the ground to the board itself and the issue got better but was still slightly noticeable. The rest of the problem got cleared up when I moved my S-video cable away from the other cables that sit behind my TV. My cable must have been getting interference from something back there. Thanks guys
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on March 10, 2012, 10:09:38 PM
Well, after all the work messing around with the ground in my DUO and cables on my TV it turns out that the problem is my TV. I just remembered that I used to have issues with vertical lines when I used a DVD player on it before with S-Video. To test this out I grabbed my old 27 inch Toshiba out of my closet and hooked it up. Dam does the S-Video look good and no lines whatsoever. I think I might end up trying to find myself a different CRT TV cause my 36" Sony Trinitron just doesn't do S-Video without showing verical lines. Thanks for the help though. This is a killer mod with the right TV.
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on April 26, 2012, 01:48:07 PM
I'm in the process of trying this mod on a white PCE I got from Samurai Ghost, I'll let you guys know how it goes!
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on April 26, 2012, 02:33:33 PM
I was actually surprised how easy it is once I got used to it. I was making it way more difficult in my head until you guys helped me out. Really the difficult part is just trying to figure where or how to mount the S-video jack itself. On a pc engine you would be best using the kind you can solder to the board since you can remove the RF and have a nice big space of ground to mount to. With my DUO-R I went with a plastic style jack that screws into the casing as opposed to one that you solder to the board. I added some glue to the jack to make sure mine was solid cause one screw is hardly enough to hold the pressure of pushing the cable in.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on April 26, 2012, 02:48:54 PM
ive done 1 with the jack having a metal box (like the controller port) and i soldered it to the RF shield (the one pictured above) the next had no shell, so i braced it and glued it to the housing
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on April 26, 2012, 04:26:56 PM
That's exactly the technique I used, I just removed the RF modulator and in its place soldered on a PCB mount S-video jack. I also put in some audio jacks, one on each side of the expansion port. I also used a 220 ohm resistor since I originally wanted to try a 200 ohm like Keith but only had 220s laying around. The colors are a tad bit washed out, but I think that might be because I'm more used to RGB these days.
But overall I'm pretty pleased with the result and now I have a PCE I can tote around to meetups and stuff with my friends!
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on April 26, 2012, 04:49:32 PM
this is a close-up of my ship in image fight showing S-Vid VS Composite (2 pics) note how the color bleeds between objects on composite S-Vid (http://pcengine.freeforums.org/download/file.php?id=49) Composite (http://pcengine.freeforums.org/download/file.php?id=48)
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on June 03, 2012, 02:40:13 PM
I just made a diagram to help those of you out who want to upgrade your video to S-video. Especially since I was confused myself when I first did this without seeing any pics. There is also info on where to tap the needed signals for both a DUO system or a standard TG16/pc engine.
Title: Re: Where can I tap a sync signal for s-video?
Post by: city41 on June 03, 2012, 04:42:50 PM
That diagram is great. I think I will give this a shot on my spare TG16 and if that succeeds do it on my main one. Thanks Keith!
Title: Re: Where can I tap a sync signal for s-video?
Post by: SignOfZeta on June 03, 2012, 04:56:06 PM
Nice! I have a long weekend coming up. I really need to do this.
Title: Re: Where can I tap a sync signal for s-video?
Post by: NightWolve on June 03, 2012, 05:24:01 PM
Thanks Keith! Awesome! I'm gonna do it for sure, was toying with the idea, but now having full/clear information, I think it'll be another fun project to do having already done the cap replacement on my Express! Oh, if you can sell me all the parts, that'd be cool! If you got extras!
Title: Re: Where can I tap a sync signal for s-video?
Post by: YAGRS on June 05, 2012, 10:02:44 AM
Question from someone who isn't very tech savvy—will this work with the Turbo CD? If not, has anyone come up with a solution for getting S-video from a Turbo CD?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on June 05, 2012, 10:09:33 AM
from the cd base it can be done with an encoder, but not this way
Title: Re: Where can I tap a sync signal for s-video?
Post by: YAGRS on June 05, 2012, 10:22:04 AM
And that, in all likelihood, is beyond my abilities at this point. Maybe someday.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on June 05, 2012, 05:19:53 PM
There is no reason to put an S-video jack in the CD base. Installing one in the turbografx system itself would be easiest and will work for both chip and CD games. You would just want to use the CD base still for the audio.
Title: Re: Where can I tap a sync signal for s-video?
Post by: ApolloBoy on June 05, 2012, 08:39:57 PM
After having done this mod to a couple of PCEs, I've found that 220 ohms is the "sweet spot" for the resistor on the luma amp. Part of my reason for selecting it was because I didn't have any 200 ohm resistors on hand and because I wanted to try a higher value. It's been tested on three different TVs (two Sony PVMs and a big Toshiba CRT) and looked fantastic on all three. I was amazed at how great it looked on my friend's 20" PVM, it looks very close to RGB!
Title: Re: Where can I tap a sync signal for s-video?
Post by: NightWolve on June 05, 2012, 09:31:42 PM
Hm, you pretty sure about that 220 ohms? Sucks about the uncertainty here, but if you say 220 Ohms is the "sweet spot," I'm inclined to use it.
Keith, I take it you're not interested with the idea of s-video mod packs, selling everything needed ready-to-go ? Wanna put my order in with DigiKey if not. BTW, in general, is DigiKey the preferred retailer around here for electrical components ?
Title: Re: Where can I tap a sync signal for s-video?
Post by: YAGRS on June 06, 2012, 02:01:39 AM
There is no reason to put an S-video jack in the CD base. Installing one in the turbografx system itself would be easiest and will work for both chip and CD games. You would just want to use the CD base still for the audio.
Okay, this is what I was wondering. I didn't know if the CD video had to come out of the CD base or not. If I can mod my TG-16 for S-video, connect the CD base, and use the S-video for both, then I'm going to try this mod.
Title: Re: Where can I tap a sync signal for s-video?
Post by: BlueBMW on June 06, 2012, 03:08:47 AM
Hm, you pretty sure about that 220 ohms? Sucks about the uncertainty here, but if you say 220 Ohms is the "sweet spot," I'm inclined to use it.
Keith, I take it you're not interested with the idea of s-video mod packs, selling everything needed ready-to-go ? Wanna put my order in with DigiKey if not. BTW, in general, is DigiKey the preferred retailer around here for electrical components ?
I typically use mouser but also ebay for odd things like logic chips.
Title: Re: Where can I tap a sync signal for s-video?
Post by: bust3dstr8 on June 06, 2012, 04:18:30 AM
What about using trimmers? Use a 0.5K and dial it in until you get the best result. There are vary small ones made that are not much bigger than a resistor.
Title: Re: Where can I tap a sync signal for s-video?
Post by: futureman2000 on June 18, 2012, 10:19:04 AM
Did this mod today, it looks fantastic! Looks way better than composite, which isn't that bad to begin with on these consoles. Also, it was nice to get the plug all on the back of the console... no more goofy av cable coming out of the left side! I didn't try any other resistor values- 220 seems just right.
Title: Re: Where can I tap a sync signal for s-video?
Post by: NightWolve on June 20, 2012, 01:20:26 PM
Thanks to futureman2000, I stopped by my local Radioshack and was able to find all parts needed except a female s-video mount which I guess I gotta buy online. But during my visit, I ran into something interesting. Apparently, RCA/Composite-to-S-Video adapters already exist. Has anybody ever tried these ? I mean, if it's possible just from the composite signal, why wouldn't a good quality TV already better process the signal ? Here are the items in questions:
Bidirectional RCA-to-S-Video Adapter "This Cables To Go™ RCA-to-S-Video Adapter is an alternative to costly active converters. The Y/C signal separation circuitry provides a crisp picture, perfect for your multimedia setup." http://www.radioshack.com/product/index.jsp?productId=2486496
Expensive one (This is the one I saw at the store): http://www.radioshack.com/product/index.jsp?productId=2102651
thesteve, what do you think about these?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on June 20, 2012, 03:53:49 PM
a good set will do T least as well........probly better the color sig punches holes in the luma sig when mixed
Title: Re: Where can I tap a sync signal for s-video?
Post by: NightWolve on June 20, 2012, 05:03:40 PM
Hmm, anybody by chance know anything about this encoder, does it work with a TurboDuo ? I'm wondering now if I should give this a shot, go all the way, not just s-video (I noticed that new LCD TVs stopped supporting it, it's down to Composite, Component, VGA and HDMI these days)... The guy wants you to email him for a price, so I'm guessing he gives a "special price" per customer... ;) Anyhow, I'm somewhat interested if the price is right and if it works.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on June 20, 2012, 05:11:57 PM
how would that help you the duo has better composite than that thing can possibly do.
Title: Re: Where can I tap a sync signal for s-video?
Post by: NightWolve on June 20, 2012, 05:20:02 PM
??? The Component output converted from raw RGB via this circuit is worse than the native composite output ???
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on June 20, 2012, 05:25:10 PM
err no the component is good if your display does 240p
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on June 20, 2012, 06:36:58 PM
Most new LCDs will still take a composite source. It's just not what you are used to seeing. You just need one of those stupid adapters for them. I had to track one down for a friend not too long ago. I mean, how much money are they really saving by not just putting RCA jacks on the TV for you instead of that 3.5mm port? http://akamaipix.crutchfield.com/products/2007/130/h130CDRM10-f_mt.jpeg (http://images.crutchfieldonline.com/products/2007/130/h130CDRM10-f_mt.jpg)
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on June 20, 2012, 06:42:06 PM
lol its real-estate not money thats what i use on the express
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on June 20, 2012, 08:24:51 PM
Oh, by all means that makes perfect sense to use it for an express since space is limited. But inside a LCD TV or plasma there is plenty of room. Not to mention if you are throwing down $500-$1000 on a nice TV don't you think TV manufactures could put/build in some composite RCA jacks for you.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on June 20, 2012, 08:30:26 PM
they dont want to remind you its just a tv
Title: Re: Where can I tap a sync signal for s-video?
Post by: grahf on June 21, 2012, 12:50:17 AM
Those jrok encoders have been around for a long time, and don't seem to work with PCE stuff for some reason. Not sure if anyone ever got one to work, but there are cheaper RGB to Component options out there.
Title: Re: Where can I tap a sync signal for s-video?
Post by: NightWolve on June 21, 2012, 05:28:26 AM
Yeah, you're right, grahf... Bad idea. I asked him about it to be sure:
Quote
I have sold at least one in the past for use with the TurboDuo, but they also used one of the sync-cleaner boards, I don't know if it's required to be honest as I've never tested it myself. From a quick read about the if the sync is very low level, then the encoder may not be able to detect it at all. Also the issue of low RGB levels output from the Turboduo sounds like it would almost certainly need an additional video amp, which the board does not include.
He wanted $50 bucks for the RGB-to-Component-only version BTW, but if you have to play around with an Amp and need this "sync-cleaner", with that level of uncertainty, it's not worth it... I'm the last person that would be able to figure it out. I guess you gotta go with those external devices you see floating around eBay.
@Keith: Yeah, the ones that I was looking at had regular Composite RCA jacks, they didn't have S-Video, though. They're not bothering with S-Video is what I was pointing out - it seems that connection standard might be on the way out with newer TVs.
Anyway, I'll just do the S-Video mod for now. Spent about $5 bucks so far, minus a female S-Video mount which I still need to find.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Kidpanda on July 28, 2012, 10:52:25 AM
What about using trimmers? Use a 0.5K and dial it in until you get the best result. There are vary small ones made that are not much bigger than a resistor.
What about using trimmers? Use a 0.5K and dial it in until you get the best result. There are vary small ones made that are not much bigger than a resistor.
yea i would think this would be the way to go :D
Title: Re: Where can I tap a sync signal for s-video?
Post by: Duo_R on July 29, 2012, 03:56:31 AM
man I saw a few initial posts in this thread but missed the rest...lol! Nice work TheSteve and others (like Keith)! I have Component video in most of my Duos, but I do have one that I would like to have Svideo on. I always intended to do the CXA1645 mod but just never got around to doing that. Now Drakon has done basically the same circuit but removed a resistor on the board, I wonder how that changes the picture compared to the way the rest of you have done it?
As far as component converters go I have had good luck with the Atlona RGB to YUV converters. As others have mentioned the Neobitz didn't work so great on the Duos. Nice work
Hmm, anybody by chance know anything about this encoder, does it work with a TurboDuo ? I'm wondering now if I should give this a shot, go all the way, not just s-video (I noticed that new LCD TVs stopped supporting it, it's down to Composite, Component, VGA and HDMI these days)... The guy wants you to email him for a price, so I'm guessing he gives a "special price" per customer... ;) Anyhow, I'm somewhat interested if the price is right and if it works.
Title: Re: Where can I tap a sync signal for s-video?
Post by: HercTNT on July 29, 2012, 04:52:24 AM
You have component "in" your duo's????
Title: Re: Where can I tap a sync signal for s-video?
Post by: Duo_R on July 29, 2012, 06:05:22 AM
Well RGB amps internally to a modified AV port sends RGB to the Atlona box which converts Tje RGB signal to component video. So it isn't internal although I could internalize if I wanted to.
Title: Re: Where can I tap a sync signal for s-video?
Post by: pdiggitydogg on October 29, 2014, 11:27:41 AM
I just made a diagram to help those of you out who want to upgrade your video to S-video. Especially since I was confused myself when I first did this without seeing any pics. There is also info on where to tap the needed signals for both a DUO system or a standard TG16/pc engine.
Sorry to bring this back from the dead, but does anyone have this diagram from Keith?
Title: Re: Where can I tap a sync signal for s-video?
Post by: SmokeMonster on November 25, 2014, 10:01:47 AM
I'd love to have the diagram too if anyone has it saved.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on November 25, 2014, 11:43:07 AM
I didn't realize it was down. Uploaded it again here. Also, I have found that for a US Turbo DUO or Black PC engine DUO it is best to get ground from the AV port. Tapping it from the sheild or common ground on the board itself doesn't produce as clear of an image. There is also another good place to get 5V and Pin 40 for the collector straight from the Hu6260 chip inside a DUO that I like to use instead of the AV jack now but the AV jack still works just fine. It's just personal preference where to tap some of the signals from.
Title: Re: Where can I tap a sync signal for s-video?
Post by: NightWolve on November 27, 2014, 12:06:10 AM
Steve's suggestion for the best place to ground your video circuit is right at the Huc6260 chip itself which would be pins 55+56. Are you suggesting otherwise in having tested the AV port versus pins 55+56 ? Also, best undisputed tap for a 5V source is the output pin for the regulator. Clean voltage right from the source not having gone past many traces to get to the AV port or wherever else you might tap it.
Title: Re: Where can I tap a sync signal for s-video?
Post by: Keith Courage on November 27, 2014, 05:10:33 AM
Yeah I've tried the two pins mentioned off of the hu6260 for the ground. still produces a slightly blurry image with a US duo on my TV. ground from the AV jack is the only place that seems to fix the issue. I've tested it with many US DUOs. I would also like to add that tapping the av jack ground fixed issues with the component video mod showing big white lines as well on US and JP Pc engine DUOs.
Could just be an issue with my TV as well.
However, I've been able to use any ground for a turbo grafx, white pc engine, and duo-r without any issues at all.
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on November 27, 2014, 07:03:17 AM
the prob is the ground on the AV jack of the US duo run a wire from AV ground to 6260 ground
Title: Re: Where can I tap a sync signal for s-video?
Post by: NightWolve on November 27, 2014, 02:16:11 PM
Hmmmm, thanks for info then Keith... Guess I have to work this info into my photo guide somehow... :/
Title: Re: Where can I tap a sync signal for s-video?
Post by: existensmaximum on March 02, 2015, 06:51:21 PM
yes the chroma could be cleaner (its from pin 20 inverted) the cap cleans the signal (smaller cap cleans it more) i just used a cap and transistor i had handy
Hello! I'm doing this mod soon, and I have a couple of questions first.
1, Earlier in the thread, you said that any NPN transistor will do. Is that true? Any? Could I try with any NPN I have lying around at home, or could I damage something..?
2, Would an even smaller cap clean the signal more? I would need to buy this capacitor anyway so I could just buy an even smaller one than 0.001 uF. Same question here - could I damage anything by choosing the wrong value?
Title: Re: Where can I tap a sync signal for s-video?
Post by: thesteve on March 02, 2015, 06:55:07 PM
Yes any NPN you have should work The cap I stated should be the smallest you can use