800xl Atari 800XL Keyboard Issue

[Classic Pac]

My saga started when a friend gave me their 800XL, turned out it had problems. Most of which was solved by a PC Tech friend who basically recapped everything. The motherboard is now perfect. Even after buying a new mylar, my friend discovered some of the keys on the keyboard are broken. Neither one of us are keyboard experts, I would love to keep the 800XL as original as possible. Can anyone help me? I need someone to look at the keyboard and figure out what is wrong.

[Beeblebrox]

A few pics would be helpful. Open the XL up and take a few shots so we know which keyboard we are looking at. Chances are if a new mylar was installed maybe some springs were lost in the process or  something is misaligned. Perhaps the mylar was damaged in the process. Sometimes over tightening the little screws can do it.

I fixed a mylar xl kb this morning funnily enough. Lots of expertise here on AA. Also Google flashjazzcat and see his YouTube videos. He shows a good few atari keyboard fixes. The 800Xl range has around 5 different types. Yours is one of the mylar types clearly. 

 

Also which keys don't work? 

[invisible kid]

You probably have to put in a new connector.

[ivop]

Also check both 4051 ICs that sit between Pokey and the keyboard connector. And check Pokey itself in another working machine, to see if it's not broken.

[+kheller2]

We need more information on what exactly doesn't work on the keyboard.

 

 

 

 

[djglish]

Which keys aren't working?  I had problems after replacing the mylar.  Turned out most of the issues were due to overtightening the little screws as mentioned earlier.  If you look at a keyboard pinout and the bad keys correspond with one pin from the connector that can help troubleshoot.

 

 

If all of the bad keys are on say pin 4 (TAB, Q, W, E, R, T, Y) then that is the problem.  If they keys feel like they aren't working properly, then you may have lost some springs as noted earlier.

[Beeblebrox]

Really useful tips above. In the case of the mylar I fixed yesterday it was a combo of coffee a previous owner had spilt over the keyboard, one broken track on the mylar, and over tightening of the little screws. 

 

I repainted the broken track after cleaning the mylar, and after a bit of trial and error I managed to get the screws tightened correctly. Fully restored XL keyboard. ??

 

One major consideration if anyone ever takes these things apart to clean, fix or replace these folding mylar types is to keep the keyboard face down on a flat surface at all times, otherwise all the tiny springs fall out instantly. ?

 

BTW this much references XL keyboard type guide thread is very useful:

 

https://atariage.com/forums/topic/105170-600800xl-keyboard-variants/

 

 

Edited July 10, 2022 by Beeblebrox

[JagChris]

I have a 600XL. I just replaced the keyboard Mylar I got from 8 bit classic.

 

What I haven't seen in the videos I could find on the subject is that hooking up the option keys first worked best for me before trying to put the main part of the keyboard on.

 

  Everything works except the red power light diode. During my fussing with it the red diode bent out a little bit and I gently bent it back into place. 

 

I don't think I broke it however now I put the machine back together it all works except the red diode does not light. What are the chances that I snapped a connection on the red diode or perhaps the Mylar isn't lining up in that area exactly right?

[Beeblebrox]

@JagChris If the led wasn't too madly bent its probably still functioning. I'd guess it is now not quite making the two connection points with the mylar underneath. Also sometimes over tightening the little screws can have a detrimental effect on mylar. I'd disassemble and try again. Whislt you are at it see if you can test the led just in case it is at fault. (Check also the area around the led for any other damage) 

Edited February 20, 2023 by Beeblebrox

[JagChris]

Thanks. I was hoping it may be something like that. 

 

Ill look into your suggestions.

[JagChris]

I hope I don't have to completely disassemble it again. Maybe I can just loosen it enough for some wiggle adjustment.

 

Anyone know off hand the size of screws that secure the keyboard into the cover on the 600XL? Mine is missing one.

[Beeblebrox]

3 hours ago, JagChris said:

I hope I don't have to completely disassemble it again. Maybe I can just loosen it enough for some wiggle adjustment.

 

Anyone know off hand the size of screws that secure the keyboard into the cover on the 600XL? Mine is missing one.

Try loosening some of a fraction first, (and where you might tighten never repeatedly overtighten as you can strip the plastic threads). 

Personally I've often found it does take a complete disassemble in these cases. I've done it a fair few times with all types of membrane based XL keyboards (as well as XE). You get better. 

 

Screw size. Can't recall but I think they could be the same as those you get for modern msata laptop pcb type hard disk drives. 

 

 

Edited February 21, 2023 by Beeblebrox