For sale on Ebay: Re-capped Tandy Model 102 (with screen issue)

[abrahamstechnology]

Hello,

I am selling a Tandy 102 on Ebay, the link: https://www.ebay.com/itm/123076524230

I have replaced all of the electrolytic capacitors on the motherboard with polymer and ceramic capacitors of the same values.

(This is my first re-cap on a vintage computer, so it's a bit messy in places, I also removed the clock battery as it was starting to leak)

There is a horizontal line of dead pixels in the screen, I suspect it's one of the IC's on the screen board, although I re-flowed them with no success. Maybe someone that knows more about LCDs could repair this.

Enjoy!

 

[GiGaBiTe]

I think it looks decent besides that SMD cap which is glued on.

Horizontal / vertical lines are usually a result of either the ribbon cable going to the screen having connection issues, or the screen itself degrading. You could try reheating each connection from the ribbon cable to the screen and on the board to see if anything changes. The screen does look like it has oxidization on the bottom that's creeping upwards though.

 

[geoffm3]

Should note that a backup battery is pretty essential to the usability of the 102.

 

[abrahamstechnology]

I think it looks decent besides that SMD cap which is glued on.

Horizontal / vertical lines are usually a result of either the ribbon cable going to the screen having connection issues, or the screen itself degrading. You could try reheating each connection from the ribbon cable to the screen and on the board to see if anything changes. The screen does look like it has oxidization on the bottom that's creeping upwards though.

Yes, the ribbon cable is pretty worn/degraded. Any idea where I can get a new one?

 

[abrahamstechnology]

I ordered a new battery, but it is wired, so I should be able to put it elsewhere in the case to keep the board safer if it ever leaks.

 

[GiGaBiTe]

Yes, the ribbon cable is pretty worn/degraded. Any idea where I can get a new one?

I don't know how the ribbon cable is bonded to the screen since you don't have any pictures of that.

If it looks like there are solder tabs on the screen assembly, you could try to use generic ribbon cable like this:

https://www.ebay.com/itm/173078152114

But if the ribbon cable looks like its directly bonded to the glass (most LCD panels are like this), then you're going to have to do some very delicate surgery.

You'll need to figure out which wire in the ribbon is disconnected, you can use something soft and blunt like a pencil eraser to push down on the connections on the LCD panel and on the motherboard to see if anything changes. If you find the broken wire, you can try heating it with a soldering iron quickly while pushing down the ribbon and see if it sticks. If pushing down the ribbon connections does nothing, you can turn off the device and use continuity testing to make sure each wire in the ribbon isn't broken.

If there are no broken wires, then the LCD panel has internal damage that's causing the line. You could try and find another LCD panel to fit in the unit, but that's a whole lot of time and money that you probably don't want to spend.