deskthority

So … the implication is that they're Alps SKCC series. Thank you. Just need a few more examples to seal it, in case Alps burnt through half the alphabet with these! The eBay ones are cream, but I can't say with confidence if they're short or tall stem.

More than one keyboard manufacturer per computer is normal — just look at the Apple IIc!

Daniel Beardsmore wrote: ↑More than one keyboard manufacturer per computer is normal — just look at the Apple IIc!

Well yes I know. I own 4 different manufacturer Atari 8-bit keyboards, 4 different Amiga, 3 different Apple II, 2 different TI and TRS-80 - and I've seen many more versions out there.

My point was that it was strange that "General Keyboard" had a switch so similar to T-ALPS - possibly actually being ALPS switches, when ALPS also supplied keyboards to TI.

Well, the way to tell is to de-solder one and see if it says "Alps" on the bottom. I am no stranger to strange.

The yellow ones are rare, but they seem to be real. The only other example I've seen is the unbranded Tatung Einstein keyboard:

https://www.youtube.com/watch?v=WpsGU7BtBlA

From the video, they appear to be 100% authentic.

Currently I have no idea how the cream, green and yellow ones differ from each other — there aren't even clear pictures of the springs of the cream ones. Another mystery is what the red thing is that goes around the contact legs, which can be absent on all switches, present on them all, or present only on some. The slot where it goes can be two different shapes, too. And that's just for the cream ones.

mr_a500 wrote: ↑It's "SKC" so it must be T-ALPS.

"SKC" is only confirmed to mean SKCL/SKCM at this moment in time, which from the primary trace side of the PCB are identical to tee mount as they use the same switchplates.

There is compelling evidence that tee mount switches are also SKC*, and in the TI-99 they would be SKCC.

I don't know where SKCA, SKCB, and XKCD to SKCK went to — I guess nowhere, since I imagine SKC* are all ones with a switchplate (which is all that these types have in common), and all the other unnamed ones do not use a switchplate. The more codes we accumulate, the clearer a picture we're going to get.

I just noticed this side shot - and the T-ALPS look white, like the TRS-80 Model III ones: Compare with the "General Keyboard" yellow sliders:

I saw the photo and they do appear to be cream tee mount, but I like to be properly sure!

Out of curiosity, roughly how heavy are your amber and green SKCC switches?

I've yet to see a single thing that distinguishes cream, amber and green, and the only thing I can think of, is weight.

If you've got a keyboard that can't be tested for actuation, then peak force (full travel) is fine, as that's a valid measurement for a linear switch (though you can't get actuation force without knowing the preload).

You just forced me to try ripster's nickel test against my will... and I've got to say, ripster's test sucks. Maybe American nickles are gummy and all stick together or something, but when I test with Canadian nickels, they don't stay in a stack and slide all over the place. It was impossible to test properly.

From just going by feel, I'd say green is lightest, then yellow, then cream. I know that's hardly scientific, but that's the half-assed level of effort I'm capable of on a Sunday afternoon.

5 pence coins work quite well. They're a little tricky to stack in large numbers — being the smallest of all coins here — but not too hard if you're careful. 3.25g each, apparently.

https://en.wikipedia.org/wiki/Five_pence_(British_coin)

I can just imagine ripster reading this and making some snide remark about Canadians not being able to stack coins. Damn you, ripster.

I normally use £1 coins as they're 5 g exactly. Last test I did, I used various combinations of £1 and 5 p. They all stack fairly co-operatively for me.

So it looks like the colour just indicates weight, as suspected.

mr_a500 wrote: ↑ Either General Keyboard made keyboards with ALPS switches, or this is a T ALPS clone.

It's General Instrument Keyboard Division, and it's [wiki]General Instrument Series S950[/wiki]:
You can't see from that photo, but it's "GI" branded: [wiki]Clare-Pendar[/wiki] as a brand (under its long-standing General Instrument ownership) must have been fading away around 1980.

STRONIC are adamant that they had exactly one S95210 E9 switch, and that I have it. However, this is what their website told me I'd get:
STRONIC seems to be one person whose English isn't very good and I failed to even get an acknowledgement that something is afoot, since clearly he had two different switches, one matching those from the Tatung Einstein and TRS-80 Model III (amber) and one matching his S95010 (ivory). All attempts to get any kind of documentation on these (even just packing slips from his own sources) failed, but they all basically match the S950 catalogue page I got from Electro-Mech. It seems that amber vs amber seems not to have any important meaning, but it may indicate age. Really someone who speaks French needs to interrogate them.

The keycap mount is indeed different. It fits Clare-Pendar keycaps (the switch depicted is from a Tatung Einstein):



This keycap came with an unidentified "ASM MEXICO" switch that appears to be S88010. (I also have the matching clear tops, that the Electronic Surplus site insisted did not come with them.)

The switchplate front panel is so close to real Alps that I'd not be surprised if Alps were actually making some or all of these parts — the differences even within S880 and S840 batches are so pronounced that it seems unlikely that they'd replicate Alps mould numbering so perfectly.

Starstruck!

Daniel Beardsmore wrote: ↑

mr_a500 wrote: ↑ Either General Keyboard made keyboards with ALPS switches, or this is a T ALPS clone.

It's General Instrument Keyboard Division, and it's [wiki]General Instrument Series S950[/wiki]:

Brilliant research. Well done.

My thanks to Nuum for kindly flagging my spam. He may have a tasty cookie.

While I am being deleted, let me note this from my profile:

Username:Robert Barton
Location:Pakistan
Main keyboard:ck721
Main mouse:Logitech
Favorite switch:Razer Green Switches

One part of this may in fact be true.