Sega Mega Drive 32X Bad Video

Picked up three 32X units off the internet that were sold as-is. Found that three of them all work to some degree. However, the jittering/distortion in the video above might be common to all four of the 32X units I own at the moment. I’m looking forward to testing this out more extensively when I find the time. One of the 32X units would not show any video at all. Gave it a clean out and it now works well. I have a video to upload with the details on what I did for that also – stay tuned!

In the past week, I have also received a Mega Drive 2 with Mega CD 2 unit – both were dead. The Mega CD is an easy fix. The pico fuse is broken, just like the Mega CD 1 unit I had. I am pretty sure the fuses are exactly the same too which is handy – I should have a spare somewhere. The CD deck seems to be working a charm.

The Mega Drive 2 that was coupled with it seemed to be dead at first. I noticed just today that it appeared that the unit did have some life left in it. Sure enough a dry broken joint on the DC-in power socket. Not the first time I’ve come across that! Gave it a quick resolder, looks like it might have been repaired in the past, and it roared to life with some Aleste. I managed to complete the first level before realising I had left the soldering iron on in the other room – whoops!

Stay tuned, we should have some more exciting things coming up in the next week as I try to repair the Mega Drive with video problems that I previously reported. Also, I need to upload some video of other things I was trying with those Saturns. Until next time, keep powering on everyone!

Edit 2018-02-06: There is an official tech document from Sega detailing this issue with PAL VA4 units and (at least) PAL 32X units with a repair workaround.

4 thoughts on “Sega Mega Drive 32X Bad Video”

  1. VDP = video display processor.

    Looks like the 32x has problems with its own video signal. The stuff it gets from the Megadrive is fine, thats why the menus and the HUD is correct, but the 32x part is screwed. Retrace the lines going from the 315-5788 (the video muxer) to the SH2 main board and search for bad caps/resistors/broken trances.
    The shaking is due to the sync line being bad and the color dropout is due to the RGB lines being bad.

  2. VDP! Perfect! Haha!
    Why do they have so much EMI shielding? AND WHY IS IT SO DAMN SHARP?
    I am not looking forward to fixing / diagnosing these as much as I should be.
    They are such a strange design.
    Why are all the main chips jammed onto the small PCB that slots into the Mega Drive?
    No idea when I’ll find time to look into these ones sadly. They’ll likely sit sprawled over my bench for weeks and possibly months to come yet.

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