Keyboard woes

[gozar]

I have three machines with various keyboard problems. Is it worth it to try to fix them?

 

The AWC (number 70166201) keyboard just has two "columns" that don't work, I just don't know how to repair them. Another 800XL keyboard causes the machine to not start up when plugged in. Finally, none of the keys on my 600XL keyboard except for the RESET/OPTION/SELECT/START/HELP keys.

 

I can pull up more about the keyboards, if it's worth fixing them (I hate throwing things out)

[flashjazzcat]

Definitely worth fixing! I threw out an old XE keyboard just because it was yellow when I ordered a new one from Best Electronics years ago. Regretted it ever since. Never scrap anything if you can avoid it.

 

XL keyboards, meanwhile, are very "fixable", so it's well worth researching the topic on the forums. There's lots of information floating around.

[+BoatofCar]

I recently repaired a 1200XL keyboard using the instructions found here:

 

http://retrobits.net/atari/keyboard.shtml

 

I don't know if it's the same as other XL keyboards, though.

[flashjazzcat]

There's a great thread here all about the different types of XL keyboard:

 

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

 

Some use a mylar, some mechanical switches, so the repair techniques will all depend on which model you have. Mechanical switch keyboards are easy: you just take out the offending switch and solder in a new one (if you can find a replacement), or if you're luckier still, there might be a broken solder connection. Mylar versions will require conductive paint to bridge discontinuous traces.

[+orpheuswaking]

Don't forget it could also be the Keyboard Multiplexer ICs - Do a forum search and a bunch of info should come up.

[gozar]

I looked at both of those, but I couldn't figure out where to start with the Type 2 keyboard on the 800xl. It's just two columns, so I figured it would be the easiest to repair, but I just can't see anything wrong with it.

 

Do the keys come off? What do I look for first? (I don't see anything like what's on the 1200xl keyboard page)

[gozar]

Success. A bad multiplexer IC on the motherboard. One fixed!!!

[gozar]

Ok, I was making it a lot harder that it was. One keyboard was fine, three of the keyboards with mylar just needed to be dissassembled and then reassembled. Two of my 800XLs needed one of the multiplexer ICs replaced. I'm assuming that's what my 600XL also needs, I just ran out of chips from my donator 800XL.

[re-atari]

Ok, I was making it a lot harder that it was. One keyboard was fine, three of the keyboards with mylar just needed to be dissassembled and then reassembled. Two of my 800XLs needed one of the multiplexer ICs replaced. I'm assuming that's what my 600XL also needs, I just ran out of chips from my donator 800XL.

It's easy and cheap to get your donor XL complete again, as the demux IC's are standard CMOS parts, CD4052 IIRC. They are still readily available in electronics shops, and should not cost you more than $1 a piece. Be cautious when handling them, they are susceptive to static electricity.

 

re-atari

Edited February 5, 2014 by re-atari

[gozar]

Jameco has them for $.39 a piece. What other standard chips should I buy? Anything under $10 and they add $5...

[Bryan]

For a while I would buy XL's with the good keyboards and get rid of ones with the mylars (or swap the keyboards). Now I don't have to worry about it.

 

My favorite one has outlines instead of inverse lettering, but there's more than one type like that so you have to look closely.

[thegamezmaster]

Any pics of the good keyboards? Know of a good place to buy them that doesn't charge high prices?? Got two 800XL's with the mylar keyboard. Tried reading the repair guides but too much stuff on them and get lost. Thanks.

Edited April 28, 2014 by thegamezmaster