deskthority

An ex-XMIT board this week; this time the one NMB Hi-Tek switch I haven't discussed yet; tactile Space Invaders. Hope you enjoy the video!

The best guess I have is that the notches on the outside of the modifier keys are to make the stabilizers work better. The stabilizers on long space invader keycaps are crap, and in particular a 2.75u right shift is horrible. By adding a little notches on the outside, they can move the switch inwards a bit, and reduce the amount of torque the stabilizer needs to handle. Personally I think they should have just shortened the right shift key to 1.75u and put some other key to the outside of it.

jacobolus wrote: The best guess I have is that the notches on the outside of the modifier keys are to make the stabilizers work better. The stabilizers on long space invader keycaps are crap, and in particular a 2.75u right shift is horrible. By adding a little notches on the outside, they can move the switch inwards a bit, and reduce the amount of torque the stabilizer needs to handle. Personally I think they should have just shortened the right shift key to 1.75u and put some other key to the outside of it.

While I agree with you overall, the feel of the stabilizers seems to vary quite a bit from board to board. I have a few where the right shift feels pretty acceptable; all seem to be later model keyboards in like new condition. I suspect that if the stabilizer wire is bent from its original form or misaligned, the feel goes to crap. It is definitely a poor design, but probably one guided by cost more so than function.

I totally agree on the 1.75u right shift. Too bad they didn't do as Focus did and use a 2u backspace and put the backslash to the right of a 1.75u right shift. The focus style layout makes the AT enter much more acceptable.

Yes, the tactile definitely seem to be the lesser of the switch triumvirate. I imagine that the 725 series switch was conceived and designed to be a linear switch. At some point there was demand for a tactile switch and the fastest and cheapest way to add tactility was the bent contacts; the other components remained unchanged. Clicky required a new design. Was the tactile switch merely a stopgap while they pondered the clicky switch? Not sure. Interestingly, even in the 1990's when most keyboards using the 725 series had either white linear or black clicky switches, the some what plentiful RT101+INTEL came with grey tactile switches and was made until at least 1994.

What happens with space invader stabilizers after some amount of use is that the plastic gets a little groove worn into it where the metal stabilizer rubs against it, and this prevents the wire from properly holding the keycap level (Chyros: you should try pulling the right shift keycap off, and examining the plastic on the underside). You (Engicoder) might be right that the metal wire could also get bent.

But even when brand new, the stabilizers on the right shift keys aren’t all that great.

Overall, they just had a bad stabilizer design compared to Alps or Cherry or IBM &c. If building custom space invader boards, I recommend sticking to 1u and 1.5u keycaps and not using stabilizers.

Thankfully, they did do an okay job with spacebar stabilizers, even on the split spacebar models.

jacobolus wrote: What happens with space invader stabilizers after some amount of use is that the plastic gets a little groove worn into it where the metal stabilizer rubs against it, and this prevents the wire from properly holding the keycap level (Chyros: you should try pulling the right shift keycap off, and examining the plastic on the underside).

Can confirm. The plastic is ever so slightly warped where the stabiliser is. Also I have a NIB Space Invaders board where the right shift works perfectly.

To be honest I think these Space Invader switches don't react all that well to use and/or dust anyway. Not as bas as Alps maybe, but definitely quite noticeable.

I don’t think dust is too big a problem for practical use day to day, more a problem with 20-years-on-a-dusty-garage-shelf storage.

Well the brand-new one I have is definitely smoother and doesn't bind on all the keys like my other boards do.

I'll side with Jacobius on this one. Don't generalize so hard from a small base! I've got a very nice black space invaders board (you've surely seen me link it before for its multicolored dyesubs, brilliant white PBT spacebar and moderately yellowed case) which is in between the use levels you've encountered. Definitely used a good bit over the years (it was DT's Facetsesame's before me) but spared grimy storage conditions. It still feels fantastic. But that dumb dumb stab in that dumb dumb dumb right Shift is completely to shit. The switches are much better than the crappy stabs they're paired with. Though fortunately NMB got the spacebar stabs just right! Where it matters most.

Muirium wrote: I'll side with Jacobius on this one. Don't generalize so hard from a small base! I've got a very nice black space invaders board (you've surely seen me link it before for its multicolored dyesubs, brilliant white PBT spacebar and moderately yellowed case) which is in between the use levels you've encountered. Definitely used a good bit over the years (it was DT's Facetsesame's before me) but spared grimy storage conditions. It still feels fantastic. But that dumb dumb stab in that dumb dumb dumb right Shift is completely to shit. The switches are much better than the crappy stabs they're paired with. Though fortunately NMB got the spacebar stabs just right! Where it matters most.

Oh I'm just throwing it up for discussion.

From the video I feel it has a soft and warm sound, something I really like on a keyboard.

I guess I could enjoy using that switch (if only it was still made).

Definitely one to get. They're not super rare, really. I have almost as many Space Invader boards as I have SSKs…

amospalla wrote: From the video I feel it has a soft and warm sound, something I really like on a keyboard.

I guess I could enjoy using that switch (if only it was still made).

They turn up often enough, I'm sure there are many people that would like this switch.

oh...here's that 101+ keyboard topic.
I have the yellow two laugh eyes too but mine is near to Yellow and pale green. And your looks like yellow at all.
Could you mind to show me the label on the back case?

terrycherry wrote: oh...here's that 101+ keyboard topic.
I have the yellow two laugh eyes too but mine is near to Yellow and pale green. And your looks like yellow at all.
Could you mind to show me the label on the back case?

Yes, it's very yellow, not green at all.

Here's the label .

Thanks. We have the same P/N but your keyboard was early. Should be made in 1988.01~03.
The yellow two laugh eyes(space bar) could be seen in 1988 made 101+keyboard only.
One thing to remind you. It's beige not brown.

Yeah I was torn between beige and light brown, the switches in the board are definitely of a much lighter shade than the loose tactile switch I own, but I think I've seen actual proper brown switches too, so that's why I went with that.