Japanese Mega Drive, Scart question?

[lettuce]

I have just gotten a Japanese mega drive from and i have a scart cable which has the headphone cable so you can get stereo sound from the MD, with the MD connected up to my hantarex monitor (that i use for all my retro consoles) all i get is an inch blue bar rolling up the screen with a game cart inserted and just a buzzing sound for the speakers. Does the Japanese mega drive require different wiring in the scart cable or if not any ideas what the problem might be?

[Fudoh]

The output on the PAL and JP MDs is the same. Maybe the cable is wired for japanese scart pintout while your monitor adapter expects european layout (or vice versa?).

[lettuce]

This is the cable i got........

http://www.ebay.co.uk/itm/Sega-Megadriv ... 1c22478a02

Says it works with PAL and Asian/Japanese consoles, so i dont think its the cable that is at fault, any other ideas?

[lettuce]

Anyone have any experience with display problems for a Japanese MD?

[Fudoh]

If you don't even get proper sound and the cable is ok, then the MD probably doesn't even properly boot up.

[ninn]

I got several japanese megadrives, and they all work great on the same cables.

Do you have an european Megadrive to check?

As far as I know, MDs do not output raw sync on pin 3, but sync from composite video. I saw a guide, how to change that by cutting a trace, but I cant find it now.

[gray117]

Not regionally on the megadrive, just different wiring pinout on scart depending on region of the cable. Cables for megadrive 1 / 2 are different though so you need to match those up - not sure if you'd mix that up though since you'd have issues with the connector.

Instinctively I'm suspecting a faulty component - probably a wire or few loose in cable. However, couple of variables to chase down though:


Hantrex monitor as in arcade, or a different unit? How are you connecting the scart?

Have you been able to confirm operation of the megadrive via another connection/screen?

Have you been able to confirm operation of the cable via another device/screen?

[ninn]

Does this help? http://nfggames.com/forum2/index.php?topic=2097.0

[ninn]

... at least the sound should work ...

[Overkill]

As far as I know, MDs do not output raw sync on pin 3, but sync from composite video. I saw a guide, how to change that by cutting a trace, but I cant find it now.

Maybe this?
http://www.assemblergames.com/forums/sh ... -mod/page3 it's talking about cutting pin 6 on the sony chip

[Fudoh]

not neccessary. To get raw sync from the MD you simply use the proper pin in the output and add a capacitor to the line. No need for any internal modding or tapping.

[lettuce]

Thanks for the suggestions. I have got it working now, must have been a faulty or maybe even under powered PSU. I was using a 3rd party 9v 1amp adapter, tired a 10v 1.2amp one and it works!!

[Fudoh]

12W is still kinda borderline. The original japanese PSUs got hot as hell. If you played an hour or two, check your current PSU's temperature.

[Lawfer]

Did Sega ever release an official 21-pins scart for the Megadrive in Japan? I know they did so for the Saturn in Japan

[Fudoh]

I don't think so. There were official european ones, but I've never seen or heard about a JP21 version.

[Lawfer]

I don't think so. There were official european ones, but I've never seen or heard about a JP21 version.

The Saturn pins layout is different so it does not fit in, I read on a forum someone on ebay used to sell modded ones with the din input changed to be similar to the saturn one or something.

[Fudoh]

MD2/SAT are interchangeable if you bend the pins a little.

For the MD1 there's no point in an official cable anyway. They would have use the composite video output for sync, which causes a lot of picture artefacts. Getting GOOD custom cables for the MD1 is easy.

[ApolloBoy]

They would have use the composite video output for sync, which causes a lot of picture artefacts.

My SMS/Genesis/MD SCART cable uses composite video for sync and I don't have any problems like that.

[Fudoh]

you certainly have. All MD revisions are jailbar-ridden as long as they use composite video for sync.

[ApolloBoy]

you certainly have. All MD revisions are jailbar-ridden as long as they use composite video for sync.

Do you mean the jailbars you get with blues? Aren't those caused by interference from the color subcarrier signal on the VDP? I have those but I haven't noticed any other flaws. I've tried experimenting with composite sync and I noticed zero difference between that and composite video.

[Fudoh]

you can usually get rid of 95% of the jailbars when using c.sync with a capacitor in line to buffer the signal. I didn't do the VDP mod for ages on my MD and it was still practically jailbar-free on my XRGB-3 and Mini.

Gunstar Heroes, MD1, raw sync, no VDP mod, XRGB-3: