shift key the culprit

[newTIboyRob]

Hello fellow Atarians:

 

So I had posted previously in a general repair cost thread that I have an 800XL with a broken space bar.  (I decided to make a new post here just as an update the old thread.)

 

Turns out I was wrong.  It wasn't the space bar that is broken, it is shift key related. I dug here up along with a 1993 Sanyo TV.  It booted up perfectly, but when I pressed the simple 1234567890 keys, without pressing any Shift keys,

it resulted in the printout shown in photo #3. Obviously what printed on the screen are the characters above the respective keys, though I didn't even use Shift. Neither Shift key is stuck in the down position, through the right one isn't quite as responsive as the left. But again, neither is actually down.

 

Any thoughts on this?  What's me next move?

 

 

 

Edited August 14, 2023 by newTIboyRob

[Beeblebrox]

We cannot view those pdf attachements. Can you post images instead?

 

Can you also repost a full hires image of the PCB so we can see if the machine is socketed, etc? 

 

Did you look into the replacing the two 4051 chips just in case they are failing and have a part to play? 

 

Also just a friendly tip. The title of this post (shift key the culprit) doesn't really tell us much and later on for future forum members searching for a similar issue/fix won't easily see what the thread is about.

 

Also you can link to your previous post here so people can read it if need be and you don't get repeated advice or comments. 

 

😁

Edited August 14, 2023 by Beeblebrox

[newTIboyRob]

You bring up valid points. Ok, will do.

[Beeblebrox]

No worries. Thanks. 😁