need help 2600 heavy switch board

[bah]

Hey everyone.

 

I have heavy 6 that was my main machine. A couple of weeks ago it started only playing for about 30 seconds before the screen went to color bars or static. Sometimes even corrupted graphics. When I turn it off, then on, the problem is exactly the same. If I turn it off and wait say 5 minutes, then it will let me get another 30 seconds of play.

 

So far I have swapped out the switch board and was able to play as normal. Voila the problem is on the switchboard. Assuming it sounded like a capacitor going bad, I replaced the main 3 caps (the big 22000 mf and the 2 large green "chicklets"). No change in problem at all. My voltage out is 4.99 volts before and during the problem so the voltage regulator seems fine.

 

What are the next items to check? This is an early Sears heavy with no 2/3 channel switch and It almost seems sacrilege to not have it running again.

Thanks for reading

 

BAH

[pags35]

Hey everyone.

 

I have heavy 6 that was my main machine. A couple of weeks ago it started only playing for about 30 seconds before the screen went to color bars or static. Sometimes even corrupted graphics. When I turn it off, then on, the problem is exactly the same. If I turn it off and wait say 5 minutes, then it will let me get another 30 seconds of play.

 

So far I have swapped out the switch board and was able to play as normal. Voila the problem is on the switchboard. Assuming it sounded like a capacitor going bad, I replaced the main 3 caps (the big 22000 mf and the 2 large green "chicklets"). No change in problem at all. My voltage out is 4.99 volts before and during the problem so the voltage regulator seems fine.

 

What are the next items to check? This is an early Sears heavy with no 2/3 channel switch and It almost seems sacrilege to not have it running again.

Thanks for reading

 

BAH

 

Sounds like a problem of something overheating, but since you already checked the regulator before and after the problem and replaced the caps you are running out of parts on the switchboard. You might want to check the RF modulator. Check the pins before and after the problem and see if they change. Pin 1 should be ground, Pin 2 the output, Pin 3 +5v, and Pin 4 the input signal(mine reads around 3.5v) . Pin 5 is usually the channel select switch if you had one. Also check for continuity between the pins and see if there is a short somewhere. Good luck.

[A.J. Franzman]

Sounds like you definitely have a voltage problem. It may not be the regulator itself, but the +5 V connection to the motherboard. Did you only check it at the regulator, or did you check it on the motherboard too? Swapping the switchboards may simply have given you a better connection at the ribbon cable connector. The power switch would also be a suspect, but if it were flaky you would see decreased voltage at the input side of the regulator.

Edited June 27, 2010 by A.J. Franzman

[bah]

Guys,

 

Thanks for the input. A J, I went back and re-tried swapping switchboards between my 2 heavies. Both units worked. My bad for not fully checking this out first! Switched back and only the newer model still worked. The earlier model is the one with symptoms as listed earlier. I switched the jumper connector ribbon between units and one time I thought the bad unit worked a little longer, and the next time it was same as before. Long story short, I think I have a poor connection or a bad connector on the mother board to the jumper wire.

 

Next, I need to pull out the mother board and check voltage drop after the ribbon connector to verify but no time today. Packing to go on a camping vacation.

 

Thanks again.

 

bah