Left shift key not working on a Model 4

[offensive_Jerk]

I just bought a model 4, and don't know much about them.

It was running frogger when I bought it so couldn't really test much.

I brought it home and made some TRSDOS disks, but it seems the left shift key doesn't work. Other keys seem to double press at times.

Before I tear into this thing, are there any tips on getting it working? Could be something stupid for all I know, like how the TI-99 up joystick doesn't work when the caps lock key is on.

 

[bladamson]

The switches go bad sometimes. They can be taken apart and cleaned, although it's kind of a pita. I think I'd try a bunch of deoxit and some exercise before I went to all that trouble, especially if it's only one key that's bad.

 

[offensive_Jerk]

Thanks, That's what I was thinking to try first too.

 

[bladamson]

I think there were two different keyboards. One may have been rubber dome? I can't remember. One of the more serious Tandy guys will chime in I am sure.

 

[ldkraemer]

Here is a bit of information on the Model 4 Keyboard, in case you want to check the
Row & Column of the Left-Shift key.


Larry

 

[ldkraemer]

A replacement (PULL) ALPS Key Switch fixed his problem.

Larry

 

[jaycrutti]

If he ever decides he wants to replace the original with a modern keyboard, check out my replacement keyboard project:
https://www.jaycrutti.com/hardware-projects/tandy-trs-80-model-4-replacement-keyboard

 

[offensive_Jerk]

Oh man, this is amazing! I actually tossed around the idea of how about going about an entirely new keyboard. This looks amazing!!!!