PC-Engine RGB AMP Modding?

[lettuce]

So i have a few PC-Engine system's being delivered to me soon (PC-E, Core 1 and Core 2) and will want to RGB mod them. Over the years i understand there have been a few methods of doing the mod, but the most recent version seems to be the THS7314 chip and grabbing the sync and RGB lines from the actual rear expansion connector rather than the main chip on the mainboard. Is there a guide about for this type of mod at all as all the guides ive seen seem to be fairly old!?

I currently have.....

THS7314 chip
SOIC-8 adapter
75ohm resistors
8 Pin mini-din

not sure what other parts are needed i know there are caps involved but not sure which type?....220uf maybe?, im guessing a perfboard is preferred aswell for this mod?, i have seem some RGB amp kits like this....



which ideally id want but for the life of me cant find who stocks them?. Is it the same method to mod a PC-Engine as it is for a core grafx 1 and 2??

Any help would be much appreciated

[Fudoh]

220uf maybe?

will work, I've anything between 220uF and 470uF and it's all good.

complete boards are available here: http://shmups.system11.org/viewtopic.php?f=4&t=53517

[RGB32E]

Copy pasta:

There have been several similar PC Engine RGB threads started recently. Best RGB mod uses Tim's AV-DRIVER.

viewtopic.php?p=1134071#p1134071
http://etim.net.au/shop/shop.php?sc_page=105
http://www.etim.net.au/

Contact Tim and order his AV-DRIVER, end of story! Don't waste your time with THS7314 solutions that make the output over blown. Seems like a new thread about PCE/Turbo RGB mods pops up every week!

[ApolloBoy]

Don't waste your time with THS7314 solutions that make the output over blown.

Never really had any issues with the THS7314-based mod...

[kamiboy]

Me neither, everything looks fine to me. Only problem with PC Engine RGB mods is jailbars, and the AV driver does not solve that.

[BuckoA51]

Contact Tim and order his AV-DRIVER, end of story! Don't waste your time with THS7314 solutions that make the output over blown. Seems like a new thread about PCE/Turbo RGB mods pops up every week!

Does Tim still sell them? I can't find them anywhere on his store.

[kamiboy]

They were never on his store so far as I can tell. You have to be in the know and contact him directly for one.

[eatfrog]

http://www.tg16pcemods.com/

[RGB32E]

Contact Tim and order his AV-DRIVER, end of story! Don't waste your time with THS7314 solutions that make the output over blown. Seems like a new thread about PCE/Turbo RGB mods pops up every week!

Does Tim still sell them? I can't find them anywhere on his store.

Yes, he still sells them, but you need to email him to order.

[lettuce]

http://www.tg16pcemods.com/

Damn thats a good price!

[low_budget]

I sell easy install RGB mod boards for turbografx and PC engine at my website for $39 .00

www.lowbudgetify.com

they fit over the expansion port pins and solder in place. I haven't tested figment in core grafx though.

[RGB32E]

Don't waste your time with THS7314 solutions that make the output over blown.

Never really had any issues with the THS7314-based mod...

I was previously using THS7314 and THS7374 circuits and I found a picture quality improvement when using the AV-DRIVER. Give the AV-DRIVER a try and see for yourself!

[lettuce]

I sell easy install RGB mod boards for turbografx and PC engine at my website for $39 .00

http://www.lowbudgetify.com

they fit over the expansion port pins and solder in place. I haven't tested figment in core grafx though.

While that looks like a nice design, its twice as much as the other places ive looked at today, any movement on that price if im ordering 5 units?. If you could PM me that would be great.

[lettuce]

Ok am going to order some RGB amp kits from mickcris on here, i have sorted out a din connection and scart cable for the White PC-Engine system, but what about the Core Grafx 1 and 2 systems, it seem to be recommended to use this type pf 8 pin did connection.....



which looks identical to the connector already on the Core 1 and 2 system but with more holes and not to use the Megadrive 2 connection....



question is if im not going to use the MD2 type din socket, is there a suitable scart cable that can be used with the type of din connector???. Dont really want to go to the hassle of making up like 3 scart cables

[mickcris]

Ok am going to order some RGB amp kits from mickcris on here, i have sorted out a din connection and scart cable for the White PC-Engine system, but what about the Core Grafx 1 and 2 systems, it seem to be recommended to use this type pf 8 pin did connection.....



which looks identical to the connector already on the Core 1 and 2 system but with more holes and not to use the Megadrive 2 connection....



question is if im not going to use the MD2 type din socket, is there a suitable scart cable that can be used with the type of din connector???. Dont really want to go to the hassle of making up like 3 scart cables

I have premade cables for both 8 pin large din and 8 pin mini din for sale also. The only issue is with the wieght and size, shipping to the UK would be quite a bit more. Just sending amps is cheap cause they are so light. You could still use a genesis 9 pin if you remove the resistors and caps from the cable or bypass the caps and resistors on the amp board.

[Ripthorn]

Ok am going to order some RGB amp kits from mickcris on here, i have sorted out a din connection and scart cable for the White PC-Engine system, but what about the Core Grafx 1 and 2 systems, it seem to be recommended to use this type pf 8 pin did connection.....

http://ddata.over-blog.com/2/11/04/71/O ... chage2.JPG

which looks identical to the connector already on the Core 1 and 2 system but with more holes and not to use the Megadrive 2 connection....

http://thumbs.ebaystatic.com/images/m/m ... s-l140.jpg

question is if im not going to use the MD2 type din socket, is there a suitable scart cable that can be used with the type of din connector???. Dont really want to go to the hassle of making up like 3 scart cables

I'm pretty sure you can use the same mini din connector on the white PCE and core grafx 1 and 2.
Unfortunately, I do not remember of any video game that uses a mini din 8 connection for video output.
So if you do not want waste your time making cables, the best way would be to use mini din 9 connectors and wire up following the MD2 pinout, thus it would be possible to use MD2 scart cables.
The good thing is the possibility to use both composite video and CSYNC.
If you want to make the 'complete' mod, I think it's possible to use the mini din 10, following the sega saturn pinout and wire up luma e chroma.

PS: Sorry about my crap english, I hope you understand what I typed

[Tarma]

Just installed the PC Engine RGB amp into my Jap DUO - fantastically crisp picture, but some of the colours are almost excessively bright and I'm getting shadow bars across the screen as well.

I'm running the DUO through an XRGB Mini and despite messing around with the settings I'm not really making any headway into getting the picture more acceptable.

Any ideas? Perhaps I've not installed something properly?

[CkRtech]

and I'm getting shadow bars across the screen as well.

Something like this?: http://shmups.system11.org/viewtopic.php?f=6&t=44262

[Tarma]

and I'm getting shadow bars across the screen as well.

Something like this?: http://shmups.system11.org/viewtopic.php?f=6&t=44262

No, not like that, these are horizontal bars, much wider and prominent than the jail bars in those screen shots.

I'll take a photo with my iphone and post it up.

[Tarma]

If you follow the laser shot there is a black shadow running prominent with it. It's realitively faint in this shot, but very stark when seeing it "live".



Forget that this shot is not in focus, the grey/white bar bleeding across the centre is pretty obvious. The colours are waaaaay too bright as well. Anyone would think I've got the contrast pumped up too high on my TV, but I definitely haven't!!



Again, at the top you can see bleed out of the left and right of the picture.

All this is the effect of the RGB amp mod. Either it's not working right, or I've not installed it right...?

[mickcris]

Just installed the PC Engine RGB amp into my Jap DUO - fantastically crisp picture, but some of the colours are almost excessively bright and I'm getting shadow bars across the screen as well.

I'm running the DUO through an XRGB Mini and despite messing around with the settings I'm not really making any headway into getting the picture more acceptable.

Any ideas? Perhaps I've not installed something properly?

post some pics of your install if you dont mind. im not sure what could cause this though. ive seen some weird things when the din port wasn't grounded though. i have never seen your problem happen before nor remember any reporting something similar.

[CkRtech]

What power supply are you using with your Duo?

[Tarma]

The original PC Engine Duo psu.

I'll add some photos of the install when I get in from work tonight.

[Monitor]

I've had good results using the THS7314 amp on my PC Engine installs so far, but I followed an updated schematic with pull-up resistors on the color lines before the amp. I use 220uf caps instead of 330uf, 0.1uf caps instead of 82nf, and 5.1m pull-up resistors instead of 3.6m as per recommendations later in the thread:

http://assemblergames.com/l/threads/wha ... ine.45483/


RGB amp and AV port install: I use an 8-pin DIN with the same pinout as Doujindance's RGB mods. (Core Grafx pictured as it was the best shot I had of the amp + AV port connections)


Screenshots: Duo-R RGB SCART to XRGB-Mini upscaler and Elgato HD60 capture device.

[Tarma]

Apologies this has taken me so long to get-a-hold of:

[kamiboy]

You have soldered the green input wire to the wrong side of its input resistor. Or is that a capacitor? In any regard, I am not sure how much of an impact that err wil have.

[Tarma]

You have soldered the green input wire to the wrong side of its input resistor. Or is that a capacitor? In any regard, I am not sure how much of an impact that err wil have.

Ooh well spotted.

D'oh!

I'll get that resoldered regardless and check the other wires. Anyone else got any other suggestions as to why the picture may be so bright?

[Asbrandt]

Anyone else got any other suggestions as to why the picture may be so bright?

According to the AV-DRIVER thread the PC Engine's RGB outputs at 0.864vpp instead of 0.7vpp, so for a THS7314 you would need to change the termination so the amplified 1.728vpp is divided down to the correct 0.7vpp when in operation.
In theory, this means a 92.6ohm in the place of the normal 75ohm and a 395.7ohm pulldown after it (this is in parallel with the 75ohm pulldown in your receiving device, for a 63ohm pulldown) which forms input / 2.469 instead of input / 2.

Neither of those values are common from what I could find, although the pulldown resistor in your receiving device isn't likely to be a very precise one, I'd guess probably 10% at best, the +/-0.04 that'd result from using 1% 91 and 390 standard value (within 3% tolerance at worst of the exact values) resistors is probably just fine.

[Tarma]

Anyone else got any other suggestions as to why the picture may be so bright?

According to the AV-DRIVER thread the PC Engine's RGB outputs at 0.864vpp instead of 0.7vpp, so for a THS7314 you would need to change the termination so the amplified 1.728vpp is divided down to the correct 0.7vpp when in operation.
In theory, this means a 92.6ohm in the place of the normal 75ohm and a 395.7ohm pulldown after it (this is in parallel with the 75ohm pulldown in your receiving device, for a 63ohm pulldown) which forms input / 2.469 instead of input / 2.

Neither of those values are common from what I could find, although the pulldown resistor in your receiving device isn't likely to be a very precise one, I'd guess probably 10% at best, the +/-0.04 that'd result from using 1% 91 and 390 standard value (within 3% tolerance at worst of the exact values) resistors is probably just fine.

[RGB32E]

Tarma, the AV-DRIVER can be configured to output the right video signal voltage levels for PC Engine / TG16 RGB mods. The output from a fixed 2x gain IC like the THS7314 is too high for use with the NEC systems, and methods to drop the voltage levels are not ideal.