Howsit? Having recently purchased a pc engine, i am wondering if anyone here has done it (since the pc engine forun is so much fun to join). I have seen the guides where they suggest to simply tap off the ext port. With the pc engine i got it came with the av booster, in this it has a simple "amp" for the video (transistor, caps and resistor) & audio (lm358 & its friends to make it work). I have read people say the audio is quiet, i am guessing av modded sms 2 style? How is the composite un amped? Living in Australia, no go on the rgb BUT i do have the scart component converter, has anyone done this and which way, amped or un-amped? I am thinking to mod the console and maybe sell the av booster. Cheers Pete
Take a look at THIS THREAD I started on the topic, since that's where I started when I RGB modded my PC Engine. In case you can't read the schematic that was posted, I made an idiot's schematic, on the last pages you can find a final version that I used. Just make sure that you've got the ground and voltage wires soldered to the correct legs on the amp, I had them the wrong way around when I first tried it. Compare what you've got to the amp legs schematic that was posted. I've heard the audio is quiet, but I amped my audio from the get go, so I wouldn't know, since it sounds as loud as any other console. It requires nothing more than sticking a cap on the audio. I use an RGB to component converter too, no problems here, since you can use a standard Mega Drive II RGB SCART cable if you use the appropriate connector in the mod.
Ok thank you, i have a few mini din 9 pin connectors so using the md2 setup was the plan. Got a few other things to do first, just doing the research first. Cheers *edit I have a few things to get and confirm what resistors/caps I have here. I find it strange though the AV booster has the composite amp'ed as well? Do AV modded PC engine (ie just tapping from EXT port) have strange AV output?
Composite video from the expansion port is a little weak, so the TurboBooster/AV Booster has a small amp to fix that issue. The audio out of the expansion port is also fairly quiet so there's an amp for that as well. Another thing (and one I totally forgot about in the thread Fireaza linked to) is that if you're using a Genesis 2/MD II cable, you don't need the resistors and caps on the outputs, as the SCART cable will already have them. They're only necessary if you're building a cable that's straight RGB without any extra components built in.
Cheers for the reply, yes i will be using a md2 scart cable and had noted to leave those 3 x 2 components out (as per sega style). I think i will backwards engineer the composite circuit from the av booster incase i need to use composite for whatever reason. Or could i use another ths7314 for composite boosting duties? May save room. I have seen on a web page where there is an image showing (from the manual apparently) the rgb amps but using 4 transistors (i think they use sync though not composite, on train going to work lol). What audio amp do people use?
Just tap off the CXA chip, on that you can get composite, S-video and RGB too. Composite isn't good on the PCE as the colours are wrong (eg green not yellow; and colour bleeding).
Sorry no CXA chip here. Got up at 3am this morning (couldn't sleep) so what else should one do? I have to order the stuff for the RGB circuit, but I copied the video circuit from the AV booster sans the emi filter and inductor. Works just fine, didn't bother amping the audio. Sounds the same volume as a modded Master System 2, bump the volume 2 or 3 and it's fine. The 9 pin mini dins I have I got a long time ago and they don't have the shroud, seem's that is all they have now lol! Looks like it worked out ok as the socket sits smack bang in the middle of the cutout in the case! Missing the shroud allowed it to sit that smidge lower. Small circuit for the Video (composite). Will neaten it up (wiring) when I do the RGB mod.
The only PC-engine variant I've seen with a CXA encoder is the European Turbografx model. Pretty sure the other models doesn't have them. It sounds like you had your hands on the European Turbografx when you say that the composite image is bad. PC-engines normally have the best composite image (if there is such a thing) of all the systems out there. Where everything that uses the Sony CXA1145 for composite sucks absolute ass, Mega Drive, Master System and Neo Geo CD (MVS too I guess?), are the ones that comes to mind. http://www.chrismcovell.com/gotRGB/rgb_compare.html
The MVS is arcade hardware so it has no video encoder, though the AES has the CXA1145 and probably has the worst composite video of any console I've seen. Also the NGCD has the CXA1645, not the 1145.
LOL I meant the AES of course Sorry about that I thought for sure the NGCD had the 1145 too, it looked almost as bad as my Mega Drive, but I'll take your word for it
