Help needed: Dead RCA Studio II

[lazzeri]

Hello,

 

I´ve just plugged a RCA Studio II and got the following image - a pile of junk pixels. Putting a cart makes no difference.

 

http://www.lazzeri.online/pub/IMG_3323.JPG

 

I´ve tried the same setup (switchbox + power brick + TV) with another RCA and it worked as it should be. So the problem is on the RCA unit itself.

 

I know NOTHING about electronics but I do know a skilled technician who said he might help. But he said he need to study it first.

 

In my ignorance it seems like bad memory chips. What do you guys think? Anyone knows where to start from?

 

Thank you!

[+KylJoy]

Top of my head? Looks like a logic issue since the video is clean, just scrambled. One or more of the memory chips or one of the ROMs. Is there any sound when you try to start games?

 

Is the regulator (7805) putting out the correct voltage? You can use the test points on the motherboard to check. Do the caps look OK?

 

I don't think there are normally socketed ICs in the RCA Studio II. I'd socket them all, one at a time, starting with the ROMs, and immediately socket the corresponding IC in a second, known good unit and swap ICs from the bad unit into the good one until I found the bad IC - but I'm crazy like that. If you are going to do this, take your time and keep track of the good chips! These things are old and may be susceptible to traces lifting. I'd also likely desolder one side of every cap and diode and test them. Again, I'm wacked that way.