Asteroids pcb resets every couple seconds.

Dr_strange1

Member
Joined
Jul 30, 2016
Messages
59
Reaction score
0
Location
Trenton, Michigan
I bought a cheap Asteroids stand up but it constantly resets every couple seconds. Also random vectors and occasional large ships and saucers. I reflowed a good many connections, cleaned the edge connector, cleaned and reseated the chips, replaced 1 broken capacitor. Rom test stops on the 3rd beep. Says its M4 rom. Reflowed the pins on M4. Also reflowed AR board. Reset button works and doesn't seem stuck. Nothing has changed. If I'm lucky i can destroy 1 asteroid before it resets again.
 
Beeps indicate RAM failure, not ROM.

If you are getting beeps, you must replace the faulty RAM chip.

ROM errors show up as error codes under the test screen. What is the test screen showing you?
 
Whoops...sorry i meant RAM. 3rd beep is low. The manual says M4 ram is faulty. As far as a test screen....i didnt know there was a test screen. Whe i switch to test mode i just get a blank screen with 2 high beeps and 1 low beep.
 
Generally it's a good idea to socket chips. However with Atari boards, be careful, as it's very easy to get shorts under the sockets, particularly for ROM and RAM sockets. Atari did not use solder mask over the traces on the component side of the boards, and the bus traces run between the pins for the ROM and RAM. If you use too much solder on any pin, it can easily spill over and short to the traces running between pins, under the socket. These are a pain to troubleshoot when they happen, as you usually can't see them.

Also, the PCB caps rarely go bad. Atari used good quality caps, and they don't get much stress, so they generally only need to be replaced if they have been physically damaged. I have tested countless PCB (and AR) caps, and never found a bad one, unless it had been stepped on or ripped off, etc.

The more stuff you replace on PCBs, which does not need to be replaced, the more you increase your chances of introducing a new problem (shorts, pulled traces, etc), which can compound things if you are trying to figure out one problem. It's better to get the board running first, by replacing parts that you know you can prove/measure as being bad. Then once it's working, bulletproof any other components that you think need replacing.
 
Good advice! Thanks! Jeez, hope i didnt use too much solder already. So is the same true for the AR boards? I've got an AR from Centipede on my bench now. It works fine but i figured it needed the new caps.
 
Back
Top Bottom