Weird Colecovision situation

[Dreadstar]

Hi folks, I've got a gremlin somewhere and I could use some second/third/nth opinions.

I bought a Colecovision off a guy today, did a little cleaning, hooked it up, and played all the cartridges to make sure they were working. Everything was cool for about an hour and a half. I took a break, turned the unit off and left the room to work on the controllers since they were in need of some TLC. Came back, plugged in a controller, turned the unit on, and it's dead. No audio or video, regardless of cartridge or none at all. So I took the case apart and noticed right away that a solder joint has come apart. (The one where the wire shield is flattened out and soldered to the top of the metal shield above the circuit board.) As I'm taking it out of the case, another solder joint breaks (up front by the expansion port where the shield is soldered to the strip on the front edge of the board). So I resolder those, put it back together, try again, still nothing. So I'm wondering if the power's gone bad. I just checked the adapter by itself, +5v and -5v seem to be normal but the +12v is only giving me 2.5v. That can't be right, can it?

So...I know it's not a lot to go on, but is it more likely to be the adapter or something on the board? Could I have killed something by resoldering those two spots? Did the board kill the power brick, or vice versa? Should I drop back 15 and punt, walk him and pitch to the rhino, etc?

[Pete Rittwage]

What did the controller TLC involve? If you did something where it became shorted internally, it could pull too much current and kill the power supply.

[Dreadstar]

Took them apart, wiped the finger funk off the edges of the number keys, wiped the dust off the joystick mechanism, pushed the side trigger switches a few times each, and put them back together.

[Dreadstar]

Something's definitely fishy in Denmark.

After letting it sit for a while, I unplugged the brick and plugged it in to a different outlet. Got +5, -5, and +12. So I try the system again, it's stil dead, and now I'm back to getting 2.5 on the 12.

[Dreadstar]

OK now sometimes it gives me no signal, then a black screen and a low hum for about a second, then no signal again. I think I probably killed the thing in the process of trying to fix it. The first time I powered it up after I resoldered the two spots, I didn't have the top on the console so there was no cartridge door. Now that I'm looking closer I see a couple pins that are slightly out of whack. Not touching neigboring pins, just bent and funny looking. If I had a cart in there slightly out of alignment and turned the system on, how much damage could it do?

Anyway, I'm calling it a night, but if anyone has any other suggestions or ideas, please feel free to add them and I will check back in the morning.

[disgraceland]

Did you ever figure this one out? I've got the same problem: 2.5 where 12 should be. Confusing.

[omnedon]

Try a different (ideally known to be working) AC adapter.

[RickHarrisMaine]

I might be mistaken here, but if you had a TI-99/4A, i think it uses the same power supply as the Colecovision.

[channelmaniac]

Check the output of the power supply without it plugged into the game...

Check the resistance on the 12v lines in the game. Maybe you have a shorted capacitor on the board. I've seen that plenty of times on old old systems. Bad part is it's a bitch to track down which one it is.

[izarate]

I might be mistaken here, but if you had a TI-99/4A, i think it uses the same power supply as the Colecovision.

Don't do that!!!! While the connector and pinout are the same, the TI-99/4A power supply is unregulated (the regulator is in the computer) while the Colecovision requires a regulated power supply since the console doesn't have an internal regulator.