[renovigo]

Well ok then, I will keep pluging the MD on direct aux in, as the latest fw version are much more improved than the 0.81.
Thanks a lot for having look at this by the way !

[renovigo]

Hi,

Thanks for sharing this, but the problem is still here. I understand it’s very strange, but again I’m sure it only happens via the ossc, because when I make a direct connection to an aux in to my amplifier, it’s good.

So here’s what I read when pressing “info” :

00c101e400080000
0800010002db1100

[renovigo]

I’ve tested it this morning, and unfortunately no change, I’m sorry. Always the same hiss on bass sounds, exactly as reported on the another thread.

[renovigo]

I just did the test. Still the same issue with MD1 unfortunately.
By pressing INFO I get these numbers displayed like this :
00 00 03 00 30
262p 454727

[renovigo]

Hi Marqs,

I will test it as soon as possible, and let you know. Thanks for looking into this by the way.

[renovigo]

0.81 is fine, I’m using it now, but 0.83 had the issue. Then I decreased to 0.82 to give a test and the problem was still here.

Maybe it would be interesting to know if anyone encountered the problem as well.

So 0.80 and 0.81 = good for MD sound
0.82 and 0.83 = sound issue

[renovigo]

Maybe it could, but in my case the system is freshly recapped and wires for the mod are ok (I think). It’s just that I see for a while now that people with PAL systems are encountering troubles with this MD mod, and when I think about it, I didn’t see any example of a succeeded one except concerning NTSC Genesis systems.
I just have the feeling that we are missing something to make it work properly with the OSSC (main interest of the rgb bypass mod is to use the MD with the OSSC, as flat screens reveal all the hidden interferences). But I would be very interested to see pictures of a working one !

[renovigo]

That’s very strange…Maybe try a more powerful amperage PSU like I said before, just to check. I know it’s not a big difference but it worth the try.

If the continuity test says there’s still power getting through the machine, I guess there’s still hope.

Maybe check the CXA again for simple things like to see if it’s not upside-down, or if all the pins a well soldered to the board, or if there’s no little solder blob around it on the board.

[renovigo]

Didn’t ask before or maybe you’ve already mentionned it, but do you hear any sound when you put on the machine ? Because I see on your picture that the mini mega is not plugged into outlines, and it would be interesting to know if you get some sound.

[renovigo]

Hi,

I’m sorry to hear you’re still in trouble with these.
Well, I’m looking at your picture, and here’s what I would do, just for trying (in that order) :

– put the CXA back (I understand you’ve already did that).
– connecting the mini mega to different +5 and grd points ( a capacitor would be fine).
– disconnect the switchless board and try without it, just to see.
– check for false contacts on the VDP, could be a little solder which leaked to a pin beside another one.
– with all these mods, you can try to use a power brick with 9V and at least 2A (I use one with 2,5A).
– recapping the system with new capacitors + new voltage regulators (last thing to do because it’s quite long).

Honestly, I would find it very strange that an rgb bypass amp kills an entire system, because it’s just dealing with video and nothing else. But I know that the more you add mods on a megadrive, the more you expose yourself to risks of interferences between them, and sometimes it could be a tiny thing to change to get everything sorted out. But I understand it could be a pain in the back sometimes.

Please let us know about you’re investigations.

Best

[renovigo]

Hi,

I encountered that kind of problem on a pal va4 megadrive with rgb bypass installed as you did AND the CXA video amp removed. I saw on your picture that the CXA is removed too am I right ? If so, try to put it back. It seems that some people had the same problem of a machine working for 2 hours and then won’t boot anymore. It’s linked to the missed CXA. This chip seems to do more than video amplify (maybe a clock relation).

The consoles are not dead I’m pretty sure about it.

Try to put the CXA first and then see.

Best

[renovigo]

Hi,

As I’m still confused with the process of re-programing the ossc remote in order to avoid interferences with other remotes in the room, I’m permitting myself to ask for some clues on this thread too. The process explained on the wiki page appears quite complicated to me, so if anyone encountered this issue, I would be very happy to follow some explanations.

Thanks a lot.

[renovigo]

Hi,

I just found this thread as I’m getting the same kind of issues with remotes interferences with the ossc, with a Yamaha receiver remote, and an LG tv remote too. Both interact with the ossc. Quite annoying.
But I’m quite confused with the procedure described on the junkerhq wiki…Doomisforu, did you managed to sort this issue out ?

Thanks

[renovigo]

Hi,

I try to relaunch the japanase VA0 subject. Does anyone found out a solution ? I worked again on it several times, and unfortunately I get no more picture now.

This board seems to be routed in a very unexpected way.

Any clues would be welcome.

Thanks

[renovigo]

Hi,

It’s just an information post, following this thread

I removed completely the CXA1145 on my VA4 PAL MD, as it has an rgb bypass, I followed some installation clues I saw on the internet (here for example), telling myself that it worth the try -and it kind of made sense regarding the all bypass purpose-.

So I did it. And it worked indeed. BUT it didn’t worked everytime.

Everytime the console ran for more than 20 minutes maybe, once you turn it off and change the cartridge, the system didn’t boot anymore. No picture, no sound, nothing.
The weird thing is, if that happens and you open the console to see what’s happening and try to “repair” (checking voltages, make fresh solder, etc.), it can boot again ! You can play for 30-40 minutes. But again, when it turns off, it doesn’t boot anymore.

SO, if I would advise something for people who are installing an rgb bypass to a VA4 MD PAL system, DON’T REMOVE THE CXA1145. I guess this chip makes more than just video encoding, maybe some clock purposes or whatever. Or maybe it works only on NTSC systems.

If anybody encountered the same issue, or on the contrary, didn’t faced any problem at all, feel free to share !

Thanks !

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