Still trying to nail this power up issue down. I welcome any additional feedback to troubleshoot this.
And I have yet to hear from anyone on the Pitfall sound issue. I have 2 different Pitfall carts now, and the only sound I get on the CRT is running into logs. Swinging, falling, dying....no sounds. But if I hook up to an LCD TV, I hear everything.
I assume it worked fine before hand?
Checked all your soldering?
did you remove the resistor that blends the audio and video signals into one for the RF
I have not yet completely ruled out a possible soldering issue but since it seems to mostly only happen on Activision carts, I'm thinking soldering isn't the problem.
However, what resistor specifically are you referring to? When I did the composite mod, I completely removed the RF unit, the transistor 202, and resistor R209. I also removed the tall pink (I forget what it's called) but it's used for RF.
I also added a resistor underneath the board to pins 6 and 9. Is that done for either RF or composite?
Do you have any Activision carts? If you do, see what it does.
I do as of today. I purchased a second Pitfall and also Freeway. They seem to have by far those most problems. I put them in and they'll start right up on occasion. So I switched on and off in rapid succession and they'd be fine for some but then go on a run of like 12 times glitching and then it'd work again. I tested Donkey Kong (Coleco), Survival Run (Parker Bros. I think), Frogs & Flies (Mattel), Cosmic Ark (Imagic), as well as Space Invaders and Superman. All of the rest except Superman I would say had no issues. Superman had a couple but excluding the Activision titles I'd say 95% of the time the other titles came on as expected.
What do you think is the issue with Activision since you mentioned it specifically?