Black screen with sound and play

[bvanesch]

Hello everyone,

I´ve just acquired my first Atari: a 2600 six switch from Hong Kong, looking clean and with 10 games. Hooked it up by RF to my older Philips LCD screen which I also use for other consoles using RF. It picks up the signal well enough but it´s the black screen.. Sound is great though and I can play Pacman for example by feel and the other games make all the proper game sounds as well. 

 

I´ve resoldered the boards, replaced the 2200 and 4,7 uF capacitors, cleaned cartridges and the holder, cleaned the IC´s pins and sockets, but with no change. So I guess I´m switching IC´s. I´ve been reading through many of the threads on the subject here but one aspect that may help narrow it down is not mentioned:

 

Which IC is the likely culprit, if any, when you can still play the game and have crystal clear audio?   

 

Greetings, Bram, the Netherlands.

[fiddlepaddle]

before doing all that work, i would try it on a CRT, just to make sure it's the console.

[bvanesch]

I would have if I´d know of one nearby. So far my trusty Philips has never let me down and the Atari reception looks promising enough. But you are right. I thought I´d just get a composite mod done but if that fails then I´m still in the dark.

 

Still, wouldn´t a working game suggest that at least the CPU is ok?

 

Thanks for the reply, Bram. 

[overgrouth]

One might think so however, I have a friend who own a gaming shop and repairs consoles for a living. He recently repaired a Snes (I know the Snes is no Atari just working on principles and ideas here that meet the same criteria) that had a broken processor. He know the system was broken but it would kinda play games abd sound. So he used my SD2SNES to load a test cartridge that runs various display settings that give details on each thing being teated. Onces he had it screw up on a specific setting aka processor which lead to graphical errors he then knoew the processor was the bad part even though many things like auido and even visual were working. He replaces the processor and all complocations seast. This comes to show that when you have a broken processor some times it is not fully dysfunctional.