PC Engine/TG16 RGB amplifiers
I am now offering RGB amplifiers that are designed with the PC Engine and TurboGrafx16 in mind. The stock RGB levels on the PC Engine (and TG16) are way to low to be usable and this amp boosts the levels up so they are suitable for use on a RGB capable TV or monitor. It should work on a RGB capable NTSC N64, but I don't have one on hand to test it with. These have also been successfully used in a JammaSNES project. That project is for connecting a SNES or SFC up to a standard Jamma arcade cabinet.
This board uses the popular Texas Instruments THS7314 3 channel amplifier. It has a biasing network, decoupling caps and DC filtering caps. You might see some other designs that use the THS7314 and a couple resistors and that's it. Well, they are built wrong and not designed per the TI spec sheet. This circuit and pcb layout was designed by micro over @ NFGGames forum. I asked micro for his permission ahead of time to build and sell his amp design. You can also find a link to the gerber files for the pcbs in that thread.
So far to date I have built over 30 of these boards. Up to this point they have all been hand soldered. This is pretty time consuming as you can imagine, so starting with this run of boards I am switching to solder paste and a reflow device. This will allow me to build these at a far faster rate.
I have made a change to micro's circuit by opting to use 100 ohm resistors on the output rather than the original 75 ohm that he specs. I found that with 75 ohms the picture was a little too bright and over saturated where as passing it through 100 ohm resistors seems just about right. For more information, including pictures of folks installs or screenshots, see this thread @ Neo-Geo.com. My name @ N-G.com is 'broken'.
The blank PCBs are fabbed in China/Hong Kong (of course) but everything else is assembled right here in Ohio.
Each board is approx. 1.25 inches long by .75 inches wide. It's tiny. Easy to fit in even the most cramped of spaces like the original white PCE:
Very first of the finished amps. New ones have cleaner soldering and output through100 ohm resistors.
Installed in a White PCE with 8 pin mini din connector replacing the stock RF unit.
Installed in a Duo-R.
Supergrafx install
The amps are fairly easy to install. They need 5v and ground for power. Then just solder 3 wires for Red, green and blue to the amp (from either the expansion port or Hu cpu) and then 3 wires from the amp to your RGB connector on your system. You will use composite video as your sync as this is only a 3 channel amplifier. The board can be secured down with simple double sided foam tape which is provided.
White PCE/CoreGrafx/TG16/SuperGrafx/SCDrom2 can tap RGB from either the bottom side of the expansion port or from the HU cpu directly. On any of the Duo's you must solder to the Hu cpu directly to obtain RGB.
I also offer kits that include 1 amp, an 8 pin din socket to replace the original 5 pin and a Euro Scart cable. This would be suitable for all PCE systems except the original White PCE and TG16 as they don't have 5 pin Din A/V outs. You will need to roll your own cable/connector solution on those machines. Mmmonkey's website has a good guide to replace the original RF socket with a 8 pin mini din (like my White PCE pictured above).
I wouldn't say this is a difficult install, but you need good hand soldering skills when soldering to the Hu CPU and appropriate desoldering tools if removing the stock 5 pin connector and replacing with an 8 pin din.
These are $25 shipped for each amp.
or
A kit which includes the Amp, 8 pin din socket and Euro Scart cable (Euro only, no JP21) which is $45 shipped.
These are domestic shipped prices. International will cost a couple dollars more.
For those that choose the kit, here is a pic of the back of the 8 pin din and where the RGB wires need to be soldered to correspond with the Scart cable wiring:
The 8 pin din will already have the 3 rear pins trimmed so that the it can be installed where the 5 pin din was.
Here is the Scart RGB cable that I build and provide with the kit:
It's fully shielded with a foil outer shielding and drain wire connected to ground. Also has a molded 8 pin din connector ensuring it should stand up to being inserted and removed over and over again for years to come.
If you have any questions, please post them in this thread. Want to order one? Shoot me a PM.
I expect to have this batch of PCBs on hand towards the end of this week/beginning of next week. I can then begin assembling them. This is my 3rd batch of these amps to date and the first offered here @ Amibay. First two were offered exclusively at Neo-Geo.com. This batch will be offered here, Neo-geo.com and PCEFX forums.
So I imagine the first of this batch will start shipping late next week and it will take a little longer for orders which include Scart cables since it takes a bit of time to build those.
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Originally Posted by keropi
