MFoolsRun Posted April 24, 2008 Share Posted April 24, 2008 This is sorta cross-posted so forgive me if you've read this before: Here's what's up with the Coleco: When I flip the switch, the static on the TV jumps, and the static changes from black and white to green and red, but no picture ever appears. Is this possibly the notorious power switch issue? I opened the system up and everything looks normal and un-corroded, but I don't really know what I'm looking at. It's also possible that the TV is just picking up the RF interference from the machine being on, as the static changes is more prominent with the cover off the Coleco. In my disassembly, I broke one of the solder points holding the RF shield to the board. I have no idea if that's important or not. None of the power-switch issues I've read about are described like my issue, but I've never owned a Coleco before, so I don't really know. Thoughts? Quote Link to comment Share on other sites More sharing options...
Prodos8 Posted April 24, 2008 Share Posted April 24, 2008 Try cleaning the power switch by dripping some alcohol into it and working it back in fourth a few dozen times while praying. Also there's a little potetiometer in the RF modulator try adjusting that, but be careful as its somewhat fragile. You could also try doing a composite video mod, Ben Heck's is very easy and gives good results. I had a CV with a bad RF modulator that I got working by doing that. Here's a link to the mod which also shows the little pot inside the RF box: http://benheck.com/Games/Coleco/Video_Mod.htm Quote Link to comment Share on other sites More sharing options...
MFoolsRun Posted April 24, 2008 Author Share Posted April 24, 2008 Thanks for the reply, I'll check out that link when I get home. Since the static does change, the system is powering up, right? How likely is it that the system can be restored to working order? Quote Link to comment Share on other sites More sharing options...
MFoolsRun Posted April 24, 2008 Author Share Posted April 24, 2008 Is there any indicator I could use to determine whether it's worth trying the composite hack? Any way I could tell if the system is truly dead? Quote Link to comment Share on other sites More sharing options...
Ikrananka Posted April 24, 2008 Share Posted April 24, 2008 Is there any indicator I could use to determine whether it's worth trying the composite hack? Any way I could tell if the system is truly dead? Do you have a multimeter? If so then you can at least check to see if power is getting past the switch. Quote Link to comment Share on other sites More sharing options...
MFoolsRun Posted April 24, 2008 Author Share Posted April 24, 2008 Is there any indicator I could use to determine whether it's worth trying the composite hack? Any way I could tell if the system is truly dead? Do you have a multimeter? If so then you can at least check to see if power is getting past the switch. I don't. I'm gonna have to get one (and a soldering iron) if I'm going to keep up this hobby, though Quote Link to comment Share on other sites More sharing options...
ckrtech Posted April 24, 2008 Share Posted April 24, 2008 Not getting too far off topic, but I got my multimeter pretty cheap at a pawn shop. You may find some handy tools for cheap if you check there. Good luck with your issue. From the sound of your topic, I was praying that you only had the channel set incorrectly. haha. Quote Link to comment Share on other sites More sharing options...
Tony Montana Posted April 25, 2008 Share Posted April 25, 2008 (edited) It sounds to me as if the system IS powering up when the static jumps and changes colors. Have you tried it on a different TV ? maybe the TV you are using is unable to tune into the CV On a side note - I would like to ask you a question. Is there a wire soldered to one of the pins on the bottom of the expansion port (at front of motherboard) and runs to a point on the motherboard ? Like the picture i have attached ? Thankyou Edited April 25, 2008 by Tony Montana Quote Link to comment Share on other sites More sharing options...
MFoolsRun Posted April 25, 2008 Author Share Posted April 25, 2008 It sounds to me as if the system IS powering up when the static jumps and changes colors. Have you tried it on a different TV ? maybe the TV you are using is unable to tune into the CV On a side note - I would like to ask you a question. Is there a wire soldered to one of the pins on the bottom of the expansion port (at front of motherboard) and runs to a point on the motherboard ? Like the picture i have attached ? Thankyou There is NOT a wire like that. What does that mean? Quote Link to comment Share on other sites More sharing options...
Tony Montana Posted April 25, 2008 Share Posted April 25, 2008 It sounds to me as if the system IS powering up when the static jumps and changes colors. Have you tried it on a different TV ? maybe the TV you are using is unable to tune into the CV On a side note - I would like to ask you a question. Is there a wire soldered to one of the pins on the bottom of the expansion port (at front of motherboard) and runs to a point on the motherboard ? Like the picture i have attached ? Thankyou There is NOT a wire like that. What does that mean? I have no idea mate, I am trying to determine if it is a mod that has been added by a previous owner. I have no idea what it is there for Thanks for your reply Quote Link to comment Share on other sites More sharing options...
MFoolsRun Posted April 25, 2008 Author Share Posted April 25, 2008 So does anyone have a recommendation for what to try next? My guess is buying a multimeter and checking the switch. How hard could a multimeter be to use? Quote Link to comment Share on other sites More sharing options...
doubledown Posted April 25, 2008 Share Posted April 25, 2008 It sounds to me as if the system IS powering up when the static jumps and changes colors. Have you tried it on a different TV ? maybe the TV you are using is unable to tune into the CV On a side note - I would like to ask you a question. Is there a wire soldered to one of the pins on the bottom of the expansion port (at front of motherboard) and runs to a point on the motherboard ? Like the picture i have attached ? Thankyou I can't guarantee it, but I assume that was someone's repair of a broken trace. Quote Link to comment Share on other sites More sharing options...
Ikrananka Posted April 25, 2008 Share Posted April 25, 2008 It sounds to me as if the system IS powering up when the static jumps and changes colors. Have you tried it on a different TV ? maybe the TV you are using is unable to tune into the CV On a side note - I would like to ask you a question. Is there a wire soldered to one of the pins on the bottom of the expansion port (at front of motherboard) and runs to a point on the motherboard ? Like the picture i have attached ? Thankyou I can't guarantee it, but I assume that was someone's repair of a broken trace. doubledown - checkout Tony's other thread on this. I've traced some of the connections made and none of them seem to make sense for repairing a trace. In fact extra components have been soldered to the board crossing points that were never part of the original circuitry. Just my uneducated evaluation - I'll certainly be interested to hear if you can shed any light on it further. Quote Link to comment Share on other sites More sharing options...
dashv Posted March 4, 2014 Share Posted March 4, 2014 Did you ever discover what the source of the problem was? My coleco does the same thing. The static just changes color. I have verified the board is getting the correct power and that the switch is making good connections (with a volt meter). Quote Link to comment Share on other sites More sharing options...
MFoolsRun Posted March 4, 2014 Author Share Posted March 4, 2014 It was six years ago, but if I recall correctly I tracked down a different power supply and that ended up fixing it. 1 Quote Link to comment Share on other sites More sharing options...
dashv Posted March 4, 2014 Share Posted March 4, 2014 Thanks for following up. I have tried a new power supply but it does not fix the issue for me. Quote Link to comment Share on other sites More sharing options...
bradd1978 Posted March 5, 2014 Share Posted March 5, 2014 I had a Colecovision that was giving me really poor signal and audio. Tried adjusting the pot in the RF but did nothing. Ended up doing the Ben Heck AV mod and the system worked perfect :-) I later upgraded and did an S-video mod and that looked even better :-) Anyways hope that might help 1 Quote Link to comment Share on other sites More sharing options...
19rsn007 Posted March 5, 2014 Share Posted March 5, 2014 could be the powerswitch, but could also be the PSU or the RAM.... Quote Link to comment Share on other sites More sharing options...
dashv Posted April 20, 2014 Share Posted April 20, 2014 (edited) For me it was a perfect storm. Used a volt meter to figure out the power brick was bad. After that I discover the switch needed cleaning. After that... The potentiometer in the RF box needed tweaking. Finally got a (remarkably good) picture but it only works on channel 4. Then I played Donkey Kong for 2 hours. :-) Thanks to everyone here that each gave me something helpful to look into. Edited April 20, 2014 by dashv Quote Link to comment Share on other sites More sharing options...
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