MOD: Mega Drive 2 PAL 60Hz color fix with a 2 pin crystal

Hi all

I am having issues with this mod on MD2.
The image color is not right, its sort of pinkish?
Adjusting the C2 does not seem to help at all.
I am using 22 pf for C1, and 30-60 pf for variable C2, I am wondering if this is causing the problem?

Any help greatly appreciated.

 

Hi modders,

(Have only tested with samsung video encoder, and sony CXA1145M)

Not sure if this has been posted before, however i have successfully restored colour using a 2 pin crystal to a sega genesis model 2 and i guess it would be the same for a MD2.

basically all i did was remove SMD cap at C24 and solder a 4.433619mhz 2 pin crystal to leg 5 and 6 on the video encoder. The output video was wavy, so added capacitors 3.3uf to both legs of the crystal and it cleaned the output video up quite some bit. perhaps using trim caps might be a better choice.

thought i would share, as im not sure if its known?

picture of rough install i did to a test board.

cheers

 

That wouldn't work for CXA1645 because it doesn't have a oscillator driver.

I see that console has the Samsung chip instead. I don't know the specifics for that one, though. The Fujitsu one has oscillator driver and so does SONY CXA1145.

That works for those with oscillator driver no problem.

 

thanks for the info oliveria

i have tried it with only the crappy samsung encoder and the better sony cxa1145. will update my post above, as to not confuse people.