Harris Computer Systems KB-23B (Keytronic Foam and Foil)

[nac5605]

I just picked up this Harris KB-23B off eBay last week.

I didn't know what it was, and neither did the seller. It wasn't on the wiki either, so I decided to purchase it because it seemed like a neat F122-style-layout keyboard. Considering that it had that layout, and that it had a 5-pin DIN connector, I thought it might work with my tinkerboy AT/XT converter, however it did not. Whether or not the reason that it didn't work is because something internally is fried, I will probably never know because that is certainly not a field of expertise for me.

The Keytronic F&Fs, to me, feel and sound pretty nice for something that uses rubber domes AND foam. They didn't feel as bad as I was led to believe coming into this.

The keycaps are pretty nice as well - dye-sub PBT with blue secondary legends and side printing. They have a profile that reminds me of some of NMB's caps (namely, the bottom row has a much steeper bias towards the back of the keyboard). Not sure if they are made by NMB, though.

Anyway, here's https://imgur.com/gallery/harris-kb23-b-an6hzeH a gallery of the keyboard. The parts are soaking right now, so no finished product photos until later.

[keycap]

Interesting. Are you sure those are Keytronics? They look similar but the inside well of the slider isn't usually that smooth. They look a bit more like the KT dome with sliders I have.

[nac5605]

Interesting. Are you sure those are Keytronics? They look similar but the inside well of the slider isn't usually that smooth. They look a bit more like the KT dome with sliders I have.

Well, you never can be too sure if they're not just some knockoff clone switch I suppose. But the switches are definitely foam and foil and they have "KT" molded onto the switch housing.

[keycap]

Oh, for sure! The pics you attached very clearly show these are foam and foil. I'm mostly interested in the slider itself being a different shape than any other F&F switch I've seen to date. There were quite a few switches that straight up recycled the Keytronic mount, which I assume these to be that same mount, just a different slider shape.

Sidenote: I'm glad more obscure keyboards like this are being documented, to me it's not only about the "best" ones but rather, the history of it all. And nothing screams vintage like foam and foil IMO

[nac5605]

Update:

I just noticed while putting the board back together that it actually has either a solenoid or a buzzer to receive status codes from the computer. Too bad the keyboard doesn't actually work when i plug it in, so I wouldn't be able to showcase it.

On the note of it not working with an at/xt converter: The seller said that he used the keyboard with an IBM PC XT before selling it to me and it worked just fine with that. Why would it not be working with my XT converter that I use with my XT Model F? I didn't notice anything off when I went over the PCBs.

The key feel got way more inconsistent (as did the sound) after I cleaned it. Some keys sound like they're bottoming out hard when I press them, but I checked and they all seem to be seated correctly. Who knows what happened haha. Either way, I can't use the keyboard so I'm not particularly concerned about this issue.

[keycap]

The keys themselves look like they have small plastic washers on the stems to help seat the dome mat better. Might wanna check those, otherwise I can't really think of anything affecting consistency.

[nac5605]

Sound test:

https://youtu.be/AlYEqoGmX44?si=ikRThCdLSF2ndN_G