Alps SKCL (complicated linear) with cream colored sliders?

[jacobolus]

I have here a Bondwell 8T laptop (from late 1980s, not sure what year) which I posted here http://geekhack.org/index.php?topic=53407.msg1192078#msg1192078 but finally decided to make an offer for after no one else snatched it. I’ll take some pictures and post soon, but...

* Nice double-shot Alps caps, in something like DSA profile
* Funny numpad that uses some kind of switch I haven’t seen with Cherry MX-compatible keycaps, but no housing on the switches, and a piece of clear plastic between the switches and the keycaps
* Main keyboard area uses some kind of linear Alps switch. Housing is identically shaped to SKCL yellow/green with LED cutouts [switch has no logo on top], but the sliders are much less colorful, and also a bit darker than the cream colored dampened tactile sliders.
* Long spacebar with 2 switches underneath as well as a stabilizer bar and a little plastic post
* NKRO with a diode for each switch

Someone else’s nice photo of the top of the laptop:


Anyone seen such switches before?

[fatchoi]

the keys look elegant. Quite nice

[Daniel Beardsmore]

Ah. There's a New Zealand machine of some kind with those Alps doubleshots:

http://deskthority.net/keyboards-f2/alps-as-a-doubleshot-manufacturer-t7296.html#p144882

They are indeed a lot like DSA.

Alps did make a cream linear/LED switch, that was used in some Zenith ZKB-2 keyboards for the space bar:

http://sandy55.fc2web.com/keyboard/zkb-2.html

I get the impression that it's not hugely stiffer than a regular green or yellow linear — what does a Coin-O-Meter suggest for the switch weight for yours?

I can't say owt about the other switches as you've not posted any switch photos : P

(SKCL is not literally complicated linear — "SK" means "Single-key switch" apparently, and "complicated" for C and "linear" for L are just memory aids to help remember the part numbers. Official information about Alps switches is extremely scarce, and all we have to date is mono photocopies of the 1994 catalogue and a datasheet with no year on it, plus two dated Forward datasheets for simplified Alps.)

[jacobolus]

Yeah, I wasn’t trying to imply that “SKCL” stood for “complicated linear”, just that those are two common descriptions.

You’re right, it’s the same color of slider used on the spacebar switch in this Texas Instruments 924 terminal keyboard that otherwise uses yellow Alps (with green ones for LEDs), except that the writing on the top is different.

I’ll take pictures sometime in the next couple days.

[Daniel Beardsmore]

Wait, that Texas Instruments keyboard has yellow linear (with LED holes) for normal keys, and green linear (with LED holes) for the switches that actually have LEDs?

What's different about the writing?

[jacobolus]

Wait, that Texas Instruments keyboard has yellow linear (with LED holes) for normal keys, and green linear (with LED holes) for the switches that actually have LEDs?

Yes, that is correct.

[jacobolus]

Pictures of the laptop sans keycaps, and then the keycap tops:



Keycaps top and bottom (one thing I don’t at all understand is why “End” uses mixed-case letters, while “HOME” is all caps):



Closer switches:



Switches w/ plastic over the top which take MX compatible keycaps [edit: apparently these are http://deskthority.net/wiki/Cherry_M8]

[Daniel Beardsmore]

Wow, those weird metal rings over all the Cherry M8 switches really confused me, until I realised that the broken slider I was looking at was in fact optical distortion, and that it's a clear plastic sheet with holes in :-)

What's the approximate force on those switches? 5 g coins is fine, I just want a rough idea.

[jacobolus]

Should I add coins with or without a keycap on there? With no keycap, to depress the switch all the way to the bottom takes about 15 US nickels.

These are definitely a bit heavier than the yellow or green switches, but not *too* much heavier feeling. I'd say it's maybe 5g heavier than the yellow switch? Maybe 10g heavier than green? (I dunno, it’s pretty hard to judge.)

Supposedly HaaTa has now gotten his force curve measurer thingy closer to finished, so maybe in a few weeks we can actually make some charts comparing them.

[Daniel Beardsmore]

Coin testing is always done with the keycap present (you would struggle to balance one on an MX switch!), although that's a good point, because switch specifications may be for force without a keycap (instead of with a "standard" keycap fitted).

12 nickels is 60 grams, which seems low — SKCLAR (yellow linear) in 1994 was rated at 58.8 cN, and SKCLAQ (grey linear) was rated at 88.2 cN. It will be interesting to get some accurate measurements of these.

I'll also have to go back to Sandy and see what the force is on his cream space bar switch.

[Daniel Beardsmore]

PS got a pic of the Texas Instruments 924 terminal keyboard?

[jacobolus]

Do you care about weight to depress the key at all, or to depress the key fully, or just to get it past the actuation point? [for the latter, I’d need to take the case apart and hook a continuity tester to the switch pins I think.

The TI keyboard looks just like this one http://geekhack.org/index.php?topic=33343.msg627183#msg627183, but without the little overlays, and with mostly yellow instead of green switches:

[Daniel Beardsmore]

Do you care about weight to depress the key at all, or to depress the key fully, or just to get it past the actuation point?

Actuation: that's how switches are rated.

The TI keyboard looks just like this one http://geekhack.org/index.php?topic=33343.msg627183#msg627183, but without the little overlays, and with mostly yellow instead of green switches …

Do you know which keys have the green switches? i.e. what did they consider would need a lighter switch?

[jacobolus]

The ones with LEDs in them [caps lock and compose character] have green switches with LEDs. To be honest yellow and green feel pretty darn similar. I assume they just had green switches lying around with the LEDs already stuck into the little cutouts.

I don’t know how to determine the actuation point and measure force at actuation without desoldering a switch, putting it in a plate where I have easy access to the bottom, hooking up my multimeter's test leads to the switch leads, and then adding nickels until I hear a beep. That sounds like a bit of a pain though. [This keyboard uses something like an RJ11 connector, which of course doesn’t plug into my computer.]

[Daniel Beardsmore]

So, yellow when there is no LED, and green when there is an LED? Odd.

Yes, if the keyboard doesn't talk to a normal PC, measuring actuation will be quite involved! Never mind, there's no rush. Your findings (cream slightly heavier than yellow, and yellow slightly heavier than green) seem to be right, so that gives us a good idea at least.

Sandy mentions a keyboard that used green switches, but yellow for the numeric keypad! It's still unclear why people would mix the three switches in these ways. (Yet no-one seems to have tried variable weighting!)

There's also a set of photos of a Wang keyboard with black Alps, and what appears to be cream Alps switches instead of yellow for the LED keys. It's very hard to tell whether they're cream, or yellow switches in a really washed out photo. Now we have proof that cream Alps switches are not exceptionally heavy, it could indeed be either.

[Daniel Beardsmore]

Added to http://deskthority.net/wiki/Cherry_M8 under Keyboards.

I've finally got around to creating a page for those Alps switches:

http://deskthority.net/wiki/Alps_SKCL_Cream

[jacobolus]

Feel free to use my photos for any purpose. I happily release them under Creative Commons CC-BY-3.0 license.

I’ll try to deconstruct green, yellow, and cream switches and take photographs/measurements of the spring sometime soon. I haven’t desoldered the green switch to look inside yet, but it’s clear that the yellow and cream switches have different springs: the cream switch has fewer winds [making it stiffer]. My guess is that the spring is the only difference (or at least the primary difference) between these three types of switches.

* * *

Completely off that subject, I’ve been experimenting with mixing/matching/modding old alps switches. The keyboards I have with blue and white clicky switches both are pretty inconsistent from switch to switch [I think a combination of wear, dirt, age, etc.] Anyway, the blue keyboard actually feels pretty nice to type on despite the inconsistencies, so I’ve been playing with some of the white switches.

I found that if I take the housing, spring, and slider from a dampened tactile cream switch [from AEK II], and the click leaf from a white switch, bend that click leaf slightly so that its "back" is straight [making it clickier; I suspect these started out straight and have deformed with age], and cut a few winds off the spring, I get a very nice feeling clicky switch, about the weight of the blue switches, with a louder click, and no bottom-out sound. I have only done this to a couple switches so far, trying out a few possibilities. The next thing I want to try is using one of the springs from a linear cream switch, since those are a bit stiffer, but then cutting some winds off it. This will get me a switch that requires lighter force at the start, but then gets heavier toward the bottom of a keypress. I suspect that I will prefer this to the current springs.

I hope that HaaTa’s force curve measurement device gets up and working soon. My current theory is that my criteria for keyswitches include: (1) low amount of work to reach actuation point [i.e. the integrated force to press the switch until it actuates], (2) sharp drop-off in force at tactile point, so that (3) actuation precisely at the tactile point, (4) at least a slight audible click at actuation, (5) increasing force near the bottom, so that landing is cushioned after actuation. It would be nice to try to tweak a switch based on these criteria, measure the results empirically, and then test the feel to compare.

[Daniel Beardsmore]

I don't post photos from forum members. Only from outsiders.

That's what buckling spring does have in its favour: very long pretravel. The switches are stiff, but you don't have to strike them hard.

The variables are complicated. For example, I don't like ~60 cN linear (it's just spongy to me), but Cherry MX Red's reduced force (45 cN) makes a huge difference in feel. It's not too light, and it's not mushy either. Then you have Oriental Tech switches, which I classed as linear, but I sense that it's a compound curve of some kind, created by using two different springs. Roughly, it feels like a lightweight switch (e.g. 45 cN) down to actuation, then a stiffer switch (55–66 cN maybe) from that point on, making it easier to avoid bottoming out.

The membrane spring gives you a working switch by itself — I need to play with that keyboard some more at some point. I just can't post off switches from it, as they're integrated into the keyboard. I also can't use it as (assuming I hadn't somehow broken it) it's so horrendously badly made as to be unusable. It ghosts like crazy and some of the keys jam. My Poker II is NKRO so there's no risk of ghosting from the use of lightweight switches.

I'm really surprised how much I get on with Cherry MX Red. The lack of tactility makes them feel stiffer than brown, as the force just keeps rising instead of falling off. The lack of click is desirable for the office, and while Matias quiet click (argh) switches are perfectly weighted and very tactile, MX Red is just so much smoother. The only design I've never tried full-time is SMK tactile. I am not sure whether I rate MX Red above MX Brown, but I think I'd rate it above Topre: the balance of perfectly medium weight with Cherry's smooth, crisp feel beats out the dough-kneading feel of Topre 45 cN domes. (I've never tried all-55 cN — maybe one day)

MX Red was something I figured from everything I read that I would hate, but finally found a good excuse to try them, and I'm impressed. I also really like Cherry ML, though, so there you have it … Sometimes you simply don't know what you'll like until you try it.