Sega Mega Drive 1 European PAL to 1084S-D1

[marquisor]

hello!

i just read the topics, but i'm still confused on what and how to do, to get my mega drive in sync on my 1084S.
i got the PAL 9-pin Sub-D version as widely known for sure.

now i soldered a special cable, everything fine, RGB, GND etc. audio i take from the headphone jack.
picture is pristine, crystal clear, but soon get's out of sync and scrambled.

i even don't know what the right pinout/numbering the MD1 has?`if someone could show me i can tell you what wires i soldered together.

I've found many many different mods/possibilities and pinouts, so what do i really have to do to get it working?

please help! thx very much

regards
marquisor

[Midori]

You mention soon, how soon is that? A few seconds, a minute?

As for pinout and such, viletims page has good info here: http://members.optushome.com.au/eviltim/gamescart/gamescart.htm#megamstr

This should work for you, if you already made it like this... There's something else going on.

[marquisor]

hello again! thx, that's a good source for many consoles, i'll keep it as reference!

ok, what i've done so far is:

MD1 to SCART but without 75Ohm, 220µF. For blanking I got a 220Ohm in spare... works fine on LCD TV
did the same for 1084S-D1 pinouts here with following connections (no audio as i use headphone jack for stereo, no res/caps):

1084S-D1 <- MD1

1,2 <- 2
3 <- 6
4 <- 5
5 <- 8
7 <- 3 or 7, tried many combinations
(8,9) <- tried to connect 3 or 7 from MD1 single or bridged on 1084 (8+9 together)

because it works fine on LCD TV i did not yet sold in any resistors nor capacitors... but i don't think that's the issue, as the screen, colors etc. are as they should be.

for getting sync i also tried to cut some traces. pin 7 trace on back of the board is cut. connected pin 11 from cxa1145 to pin 7. "naked" and also with caps+res's. no sync, mostly black screen.
if i cut pin 3 trace too i get sync for short time but then picture fades out i guess 5 secs not more (that seems to have smthng. to do with loading/unloading caps).


that's it so far... if anything more comes in mind i'll post more...

regards
marqs


EDIT: @Midori: with above method and no traces cut yet and composite video (MD1) connected to composite sync (1084), switched MD1 on.. first all good, after 10-15 secs there's some flickering in some pixels, 10-15 secs later white gets grey/black, background colors disappear, tearing occurs, v-hold dances, sometimes screen is out of center above, sometimes it gets correct but not for long maybe a second or so, then same distortion again