#2119a

[@nigelcleaver]

I would just like to say how much I enjoy your channel. Many (and I mean many) of your previous videos have been very interesting, informative (and prompted me to order ATTiny ICs (10s, 414/814) to experiment with. Carry on doing what you enjoy! It's good to have fun. Thanks.

[@johnlehman2157]

When I worked at NASA Houston in the late 1960's and early 1970's, there was only one computer in the building # 15. It was a IMSAI 8080 or something of that ilk in a small closet. There was only one guy that knew how to use it. and nobody seemed to know what he was doing but he spent hours going over stacks of printouts. We were impressed.

[@dalewheat]

Excellent expectation management on display here, folks. Let the man play with his toys that he built. Or do it yourself. I think it’s an adorable little IMSAI-esque tribute to the thing that he so obviously loves and has invested his time into.

[@jsdutky]

I actually went looking for this kind of toggle switch (mom-off-mom) on DigiKey and Mouser after watching your last video. I got a lot of hits, but the prices were pretty high for a toy. Also, I doubt that any of them were small enough to fit your toy board, though some might come close.

[@egoincarnate]

You could just replace each of the momentary switches with two tiny buttons?

[@humidbeing]

This is the obvious solution. Two tiny momentary SMD clickers.

[@jamesross3939]

Yep, this is the solution.

[@bayareapianist]

But you can press both switches which is a no-no.

[@jamesross3939]

@ I'm sure there is a simple circuit that could rule out that condition and only allow one button push to latch at a time.

[@ParabolicLabs]

The smallest ones I know of are subminiature 1M1-Series from carling tech. I think it was a R2 (standard paddle) and they were the smallest on-off-on paddle I could find. I don't remember if they were momentary or toggle. I only needed one, so the price didn't matter but I'm pretty sure I paid like 11 dollars or something with shipping, I think they were like 6.50 a piece. I know there are other ones like APEM SY237CD but these were miniature not subminiature. What I would do is replace them with two push buttons and 3d model a paddle that sits on top of the two buttons. All the paddles could be 3d printed and would have a single "axle" of some relatively thick diameter wire like 2mm or 3mm. That's probably the best approach imo.

[@AttilaAsztalos]

What would work here would be a thumb wheel navigation switch like the COM-08184 from Sparkfun. They're SMD, but only 0.1" wide (!) so there's just enough space left there to solder on three pins on the side, to connect them into the PCB. They do exactly what you want - momentary "up", momentary "down", rest at center. They're available from plenty of other places as well, Aliexpress or whatever.

[@makerspace533]

I built 3 IMSAIs back in the seventies and actually used them for real work. I've thought about making a real one just for fun. I think I have some 8085s around, maybe one of those old white ceramic 8080s. But, life is too short for that. I'd have to find a copy of CPM 1.4 and some 8" floppys.

[@IMSAIGuy]

you might like this: kzbin.info/www/bejne/n5SnZYZ5orRriac

[@makerspace533]

@@IMSAIGuy He packed a lot on one board!

[@mnoxman]

Nothing wrong with a blinky lights toy. I have a nano-kenback 1 from Adwater and Stur. Fun blinky toy. I'v seen a cosmac ELF in the Altoids tin. I don't know about others but I see your IMSAI as set dressing. I tagging a few others who do IMSAI videos is just spreading the joy of a toy.

[@adrienferreira4666]

Long press: low, short press: high. Doesn’t answer your question, but answers your needs. Just a firmware update.

[@TjpjMusic]

the CSS-1302MC would fit although it's a bit skinny and long. Unfortunately it seems very few if any of the big retailers stock them

[@jj74qformerlyjailbreak3]

Reeeeeeeeeeee. Imsai Mad. Lol. Love ya man.

[@randallrouth9029]

I love you little board. How much bigger would it be if you used the ubiquitous switches with 0.185" spacing? Did you consider using a max7219? It will drive 64 LEDs to without the need for dropping resisters. For the address switches, I would think that a 4x4 matrix would save in parts count. I look forward for future updates.

[@jercos]

MTS-123 is the number I see in a few hobby shops and Chinese suppliers, for a switch that could be packed as tight as 7mm. Mind you, I wasn't expecting a full IMSAI 8080 emulator, just a fancier Christmas ornament, but specifically being able to single-step the pre-patterned blinkenlights sounds very appealing.

[@IMSAIGuy]

that is twice the spacing that I have now. it would end up like this altairmini.com/en/home

[@jercos]

@@IMSAIGuy Yep, maybe it's just a collective pipe dream. You've done lovely work with the parts available to you.

[@gorak9000]

Could you do custom switches, where you 3d print the "paddle handle", and that just pushes the bog standard tactile surface mount PCB switches when you push the handle up or down? You can get those tactile switches in many different sizes, and with different levels of "clicky-ness" (yes, that's the technical term) - just go for "low-clicky" variety. Another alternative might be rubber membrane button contacts - probably give you more travel and more springiness than the tactile switches. You probably need to make a base / pivot that clips into holes on the PCB, and holds the paddle handle at the correct height above the switches, and the handle itself as 2 separate parts.

[@gorak9000]

another option could be to use optical interrupters rather than actual switches under the paddles - and I guess you need 2 different paddle designs, one that's "bi-stable" either up or down, and one that's mom-off-mom

[@argoneum]

Some optical drives had such switches for detecting if the tray was opened, closed, or "in between". Ended up using some for driving bistable relays, liked to play with them. No idea if you can still get them, had mine from scrap.

[@Gorantp]

Apem 5637 switches might be a good fit.

[@pikaonyoutube2139]

That would be interesting to build tbh 😊

[@BersekViking]

Why not use two push buttons instead of one on/off switch?

[@josephthibeault4843]

Are they signal pole, double pole. Center on or off

[@RommudohDev]

maybe it really is too small for such switches - but it really is a nice looking toy!

[@IMSAIGuy]

bingo

[@colonelbarker]

Time to call the horn of the internet.

[@Bit_byte_bit]

Mouser has a lot of sub-miniature (on)-off-(on) rocker switches. I'm sure there are a few that will fit within your dimensions.

[@IMSAIGuy]

give me a part number, no one has found one yet. the best has been on 0.300" center. this one is 0.150"

[@computeraidedworld1148]

⁠@@IMSAIGuywhat does it mean to be .3 or .15 inch center?

[@IMSAIGuy]

@@computeraidedworld1148 switch one to switch two distance

[@matteoricci9129]

Can't you use two push button?

[@Altomare3]

C&K does miniature mom/off/mom lever switches but they're hella expensive. Look up C&K ET05 series. PCB footprint is .320 x .200 in freedom units

[@IMSAIGuy]

those are big also. they would require 0.3" center to center. they are used on the altair computer and actually on the full size IMSAI.but the IMSAI uses C&K in a plastic paddle version.

[@Ouefdie]

Why not just use 2 momentary buttons for those switches on the right? Sacrificing some aesthetics for functionality?

[@kpnconsulting8739]

Wot? IMSAI Guy doesn't have an IMSAI computer? Well let's roll over to ebay and see what the story is.... MOTHER OF GOD! 4000 Ameros?!?!?!? That's more than they cost new, inflation adjusted.

[@IMSAIGuy]

I sold mine for $5000 after all the videos

[@Pickle136]

surface mount tactile switches?

[@IMSAIGuy]

no, would not have the IMSAI vibe. give me some part numbers that you think would work

[@weefween]

the switch type is called (ON) - OFF - (ON)

[@IMSAIGuy]

that's the one

[@weefween]

on mouser it is possible to filter by (ON) - OFF - (ON) and rocker switches at the same time

[@IMSAIGuy]

let me know if you find a tiny one

[@herbertsusmann986]

Why does this board have to be so tiny? There are many mom off mom switches out there just a bit bigger.

[@IMSAIGuy]

tell me some part numbers

[@IMSAIGuy]

those switches are used on the altair

[@IMSAIGuy]

altairmini.com/en/home

[@herbertsusmann986]

@@IMSAIGuy E-Switch 100SP4T1B4M2QE or Digikey part number EG5759 for example. No, not tiny but a reasonable size (mom)-off-(mom) switch. Can you just build a new slightly larger board around switches like these? Why does it have to be so tiny?

[@IMSAIGuy]

because it makes me happy. bigger ones have been done several times

[@ludmilascoles1195]

Oh no I am so disappointed 😢 Next you will tell me to ignore the man behind the curtain 😂😂😂

[@notsogreat123]

Yeah I don't think so

[@computeraidedworld1148]

Maybe NKK’s G13KP with the top removed. Mouser part 633-G13KP

[@IMSAIGuy]

Those look good. $150 per board though

[@robertvandersanden]

G18KP is the momentary version. Pretty expensive indeed, but if that yields a tiny real working emulator it may still be worth it for some people.

[@computeraidedworld1148]

@@IMSAIGuy it’s the smallest I could find. They make a bunch of versions mostly differing in color. Good luck.

[@jyvben1520]

pushbutton long press short press

[@b.c.5024]

It's your PCB design, OK? You can change it to make a common switch fit, OK? KiCad is not difficult, OK? Are you OK?

[@IMSAIGuy]

I don't want it bigger. Are you ok