How to retension a coleco adam computer's printer

[craigm71]

So I am about done cleaning and Retr0brighting my second Adam computer (I will post soon on that) and I have a big issue.

 

While tearing apart the printer to clean it, the string that moves the printer head back and forth came off the fly wheels. I have been able to make the string have tension but the second I turn on the Adam, the Printer head moves to the right, then the sting goes slack and falls off the right fly wheel.

 

I have tried a dozen times, with different methods but I am having no luck with getting it working.

 

Does anyone know a link or youtube page, I have been unsuccessful on showing me a how-to on it. Thanks!!!

[NIAD]

I don't recall ever seeing a Youtube video covering this repair and BITD, I gave up the one and only time I tried to fix the same issue. The worst part of your detailed explanation is that the Printer Head moves to the right when you turn on the ADAM ! From past experience, this usually means that a bad Printer Logic Board is the culprit and usually the Printer Head will make it all the way to the right side and continuously keep knocking until you power down.

 

Since you have the other working Printer, I would take off the lid and compare to the Printer in question that each of the small 6 connectors that run from the Printer Head Assembly and connect to the Print Logic Board are orientated correctly. Then compare the whole tension string assembly to make sure that everything is orientated correctly as well.

 

Hopefully the two Printers are the same revision to make the comparison between the two easy. IIRC, there were 3 revisions of the Printer Head Assembly and 3 of the Printer Logic Board, but they are all compatible with one another from what I've been told.

Edited May 7, 2013 by NIAD

[Kiwi]

I don't recall ever seeing a Youtube video covering this repair and BITD, I gave up the one and only time I tried to fix the same issue. The worst part of your detailed explanation is that the Printer Head moves to the right when you turn on the ADAM ! From past experience, this usually means that a bad Printer Logic Board is the culprit and usually the Printer Head will make it all the way to the right side and continuously keep knocking until you power down.

 

I did recall someone had the printer head moves to the right continuously knocking, and it turns out it was the switch shorting. He removed the switch and had it wired to be on, and the printer works properly. Turns out that the switch was faulty. I thought I may bring that up.

Edited May 7, 2013 by Kiwi

[retroillucid]

Be sure to post pics of your unit cleaned with RetroBright

[craigm71]

I was wrong guys...it goes left...it tries to act normal but cannot move the printer head so after while gives up...blah...I can't believe there is nothing out there showing the how to...

 

anyways...I will look at my second computer and see if I can get it that way

 

And yes...Retr0Bright pics soon!

[NIAD]

I did recall someone had the printer head moves to the right continuously knocking, and it turns out it was the switch shorting. He removed the switch and had it wired to be on, and the printer works properly. Turns out that the switch was faulty. I thought I may bring that up.

The normal movement of the Printer Head when the system is turned on is to move all the way to the left, cycle the print wheel and then move to the right slighly before stopping. If the Printer Head initially moves to the right and then starts knocking back and forth at the right side of the track, that is usually a very bad sign that the Printer Logic Board is bad.

 

Thankfully in craigm71's is moving to the left, so it more than likely is that contact switch that is used in all the earlier Printer revisions and there should be an easy bypass of the switch if all else fails to remedy this problem. BTW, is this the same printer that already had the problem with the switch previously?

[NIAD]

I was wrong guys...it goes left...it tries to act normal but cannot move the printer head so after while gives up...blah...I can't believe there is nothing out there showing the how to...

 

anyways...I will look at my second computer and see if I can get it that way

 

And yes...Retr0Bright pics soon!

If all else fails, at least you have a backup power supply.

[craigm71]

NIAD,

 

Yes, it is the same printer that was giving me issues before...I removed the switch like last time but it's not helping. Before, it was going to the right and when I removed the switch it worked, now, its going all the way to the left and then just tried to keep on going (even with the switch removed). Not sure if I can do anything. If its dead I will just put it away as a second power supply but I would rather get it working. Any other ideas?

 

I did get the printer re-tensioned though! Which was amazing as I was about to throw the dam thing out the window. I don't think there was any way I would of figured that out without a second printer to look at. If you have ever tried to re-tension on will know what I am talking about as you have to be able to keep everything tight so the sting does not come off the fly wheels...gah!

 

Thanks!!!

[adamcon]

NIAD,

 

Yes, it is the same printer that was giving me issues before...I removed the switch like last time but it's not helping. Before, it was going to the right and when I removed the switch it worked, now, its going all the way to the left and then just tried to keep on going (even with the switch removed). Not sure if I can do anything. If its dead I will just put it away as a second power supply but I would rather get it working. Any other ideas?

 

I did get the printer re-tensioned though! Which was amazing as I was about to throw the dam thing out the window. I don't think there was any way I would of figured that out without a second printer to look at. If you have ever tried to re-tension on will know what I am talking about as you have to be able to keep everything tight so the sting does not come off the fly wheels...gah!

 

Thanks!!!

 

So now you know that the entire problem revolves around that little momentary switch on the left side. I don't quite undrstand that you removed the switch and the printer worked; my understanding is that the switch needs to be there and operational inorder to reset the printer each time the cpu reset switch is pulled. Did you try disconnecting the switch when the printhead gets to the left? For that matter; any time the print head is moving, you should be able to hit that momentary switch and the head will recycle.

[craigm71]

Sorry i did not explain it correctly, I meant that I removed the switch by unscrewing it from the printer itself. I never de-sodered the switch. Before, I would just losen the screws from the switch and that fixed the printer head from moving all the way to the right and not stopping. Now, it is going left even if I unscrew and move the switch off the printer lie before.

[adamcon]

Sorry i did not explain it correctly, I meant that I removed the switch by unscrewing it from the printer itself. I never de-sodered the switch. Before, I would just losen the screws from the switch and that fixed the printer head from moving all the way to the right and not stopping. Now, it is going left even if I unscrew and move the switch off the printer lie before.

You need the switch, usually th head goes left and trips the switch, then goes to the right about 1/2" to be ready to print at the correct indent margin