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ADB Keyboard Repair Advice

Johnnya101

Well-known member
Hi all,

I've got two extended style keyboards. One is an Extended Keyboard II (first version), and one is a Cutting Edge Extended Keyboard.

The Apple one works fine out of the right ADB port, except the backspace key does not work. Nothing happens with the left port. I see some corrosion out of the left port, so guessing that may be the issue there. How should I fix that? Would it be better to either soak it in vinegar or evapo rust or something, or should I buy a new ADB port, or find a replacement keyboard controller board?

The cutting edge one has some weird stuff going on. First of all, it is missing the number pad equal key. I could probably fit an Apple key in there, but the color is more platinum (cutting edge used white). When trying to use this keyboard, either port kind of works. The num lock light stays lit, and sometimes when moving around the connector, different lock lights flash. I cannot type anything. I see some rust in this one...

Haven't delved into keyboards before, and these are getting harder to find, so I'd like to fix them. Especially the cutting edge one, I can't even find a photo of it online... Any help would be appreciated on how to test these.
 

Johnnya101

Well-known member
Took them both apart. They both definitely need all new ADB connectors to begin, old ones are mangled and pitted from heavy rust (strangely, rest of the board looks perfect). Where does one find new ones? Or, if anyone happens to have some extra new ones, let me know.
 

LaPorta

Well-known member
I’d figure that any S-video jack would work, pilfered from an old VCR or something…or maybe just some new ones at mouser?
 

dcr

Well-known member
I’d figure that any S-video jack would work, pilfered from an old VCR or something…or maybe just some new ones at mouser?
(y)

I bought a 5-pack on Amazon seven years ago, but I'd bet Mouser or Digi-Key would have them too. I paid $3.47 and got free shipping so it probably cost Amazon more to deliver than what they made.
 

Johnnya101

Well-known member
Thanks for the help, found some on Amazon. Knew there was a name for them.

Hopefully that will get them going...
 

Johnnya101

Well-known member
Apple keyboard: Retrobrited, came out pretty nice. Did what most say not to do, but the thing was almost junk before I touched it, so figured I had nothing to lose. Loaded the PCB/keys with degreaser and washed under very hot water. Lots of gunk and brown goo came out. Looks like it sat in water for a while, lots of corrosion. Left to dry in well ventilated are. Replaced both ADB ports. Keyboard now works, except for a few keys. Took them apart, discovered irreparable corrosion internally, so am ordering new switches. Also the caps lock LED was so corroded it fell off.

Cutting Edge (Really OEMMAX): Retrobrited, came out nice. Keys were almost orange, still retrobriting. Replaced both ADB ports. Board corroded, was sitting in water for a while like above. Also degreased and washed, because I had nothing to lose. Keyboard does not work reliably now that the ports are replaced. Once plugged in, all three LEDs stay lit, keys do not register. It did this before the wash too. Guessing some component is toast. Any ideas on how to further proceed with this one? Would really like to get it going.
 

Johnnya101

Well-known member
20220317_171503.jpg

Here are some photos. I can do any soldering required on these since it is all thru hole simple stuff. Not sure how to find replacements, never had to do this before. The large chip was getting somewhat warmish while plugged in for a minute.
 

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Johnnya101

Well-known member
I -know- this is not the right way to check, but I tested the two radial caps with my multimeter. One cap, by the power connector, tests that its working at least partially, as the meter slowly climbs up as it charges. The meter stays at 1 with the other cap, as if I didn't test anything at all. They were left in circuit. Again, know its not correct really to do this, other than to check if they do anything. Am I correct in my thinking that this cap is bad?
 

Johnnya101

Well-known member
Replaced both caps. Nothing changed. Ideas on where to go next? I don't mind replacing all the components to just rule everything out, there aren't many (besides resistors). Just don't know the modern equivalents. Unless someone thinks something shorted out?
 

Johnnya101

Well-known member
I know it would stink….but that IC could also be toastz
As long as I could find a new equivalent, I wouldn't mind. How does one even look for a new one? I have tried typing in the numbers online and nothing comes up. Guessing it would be the main controller, the big one?

Got way too much time invested in it, so I will continue on and find a way to get it going.

Long shot worse case and can't find a replacement: I will find an AEK PCB (Seem to be plenty) and move these keys + plate over to that. That will make this easier.

Edit: Looks like a similar issue with a IIe clone http://swut.net/apple-2-clone.html Had to use an arduino

I am currently trying this with a Windows 10 PC using an ADB adapter. Is there any chance a clone keyboard like this wont work with an adapter and needs a Mac? Or is ADB ADB?
 
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Johnnya101

Well-known member
Somehow was able to find this exact keyboard on ebay, but it is a different clone brand (with associated label slapped on). Seems to be in better shape, and looks like it was out of a TV studio or something, has multi colored video and audio stickers on the keys. May try swapping components to rule parts out. Assuming PCBs are the same, would swapping ICs cause any damage to them?
 

Johnnya101

Well-known member
Somewhat stupid question... I am expecting the "new" keyboard today. When I swap ICs, is there any chance of damage occurring to it if it is not the issue, and another part is dead? As in, as soon as it gets plugged in, the "new" one dies? Or will it work or not? Never done this before, and don't want to kill another.
 

Johnnya101

Well-known member
Received the "new" keyboard today. Different PCB revision. Different circuit. Not even going to attempt switching anything out.

May end up either hacking in an AEK II PCB or I'll eventually convert it to USB and throw a new controller board in. Oh well. I do notice a huge difference in switch quality. Both use white Alps, and the new board feels very different. The Cutting Edge ones are either corroded or super worn out (as evident from the almost holes worn into the key caps).
 

Johnnya101

Well-known member
I could, but one is in perfect shape and works, the one I wanted to get going has a rusty plate, worn out switches and key caps, but a better looking shell. I'd feel bad ruining one for the other.

I'm debating on throwing in an AEK ii pcb I have, but I think I'll save it to build a new AEK from parts.
 
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