I'm writing to ask you something, maybe you can help me. I found an old and dear Atari 800XL from my childhood and i want to know how i can fix it because in that time (about 20 years ago) it had a problem that could never be solved.
The problem is the following: when i load a game from tape recorder, i spend some time playing and then suddenly the screen starts to change its color, for example, the blue screen with "Ready" turns green, then red and finally appears a black frozen screen and a lot of characters filling all the screen (in certain forums they called garbage screen),then to play again i must wait some period of time, load another game, play a little time and crashes again. Some people says that maybe is a problem with the ANTIC Chip but i don't know how to test it.
I opened the case and there's no sign of something bad or burned in the main board, so i measured the voltage inside the Atari and i found that the voltage drops slowly, and reaches a point where there is only 3.70 volts which coincides with the black screen, i suppose that by failing to maintain the correct voltage, it stops working. I have tested the plug power supply and gives me 5.04v (i think is normal), so i opened the power supply and found that there is a leakage from a capacitor, i have changed it for a new one, but the problem remains. The basic diagnostics (memory , sound and keyboard) don't have any error.
Unfortunately, there's no technical services who repairs this machine near of my residence (by the way i'm from Chile). I was searching and found an Atari 800XL field service manual on the Internet and they said something about a catridge called "Super Salt diagnostic Catridge" that suppose to do a diagnostic test on every internal part to find what is the failure. So, my questions are:
¿Where can i find a copy of Super Salt catridge?
¿Do you Know what could be the problem with the 800XL and how can i solve it?
¿Is there any PC software similar to Super Salt that can be used on 800XL, maybe connecting both machines via parallel o serial port?
¿Is there any Basic OS algorithm to use instead of Super Salt (In case i can't find it)?.
It's my first time here in Atariage's forum, i'm really interested in fix it, only to have the pleasure of playing again those great games. Thanking you in advance for your answer.