deskthority

So, I had been wondering about the non-yellowing white plastic in beamspring and selectric caps was. Even in the same device, you would see the actual white abs yellow and at the same time this other plastic did nothing. While cleaning some recently, I realized where I had felt that almost slightly ...

Got mine for ten. Thanks for the heads up gainsborough. Never had the pleasure of trying monterey blue and 75% is just my style for a compact.

I use a four inch high board every day. Usability has nothing to do with the height of the board itself and more the relative height of your desk.

Gorgeous caps, and I like how there's enough buttons up top you can actually use it as a daily driver board with some creative layering. As far as caps go, the electrolytics had a lifetime of about 10 years. The ceramic and mica ones are good basically forever. Main thing I would look for on the boa...

Chyros wrote: ↑Jaysis, how am I going to get one of those?! xD

I'd loan you mine if you were in the states, but I like it too much to risk two Atlantic transits.
If you can find one, they're pretty cheap though like most oddball old terminal boards.

Looks great. How did you hook it up? Just rows and columns to a teensy?

I've also been meaning to ask this from all the stackpole and hi-tek switches like this you see on stuff like the old TI home computers. Does lube on the stem help at all with the feel?

Thought beamspring wobble was just a function of the key cap loosening up over time on the thin and small metal tab that it mounts on. Mine were on so tight I got blisters on my fingertips taking them off. Maybe that happens to ones that had the metal stuff sanded or restored? Also, there's a tiny ...

Wobble is a function of the condition of the foam I think, or maybe the plastic rings in the plate mount. My 3278 fullsize has immaculate foam and almost no wobble. Man, that 5251 board is pretty though. I see I'm not the only one who's been trawling for some blue selectric keycaps lately. Got some ...

Generally, 320 is pretty heavy duty. You can see the grain tracks in that red cap. You probably want to go with 800 to 1000 and then follow up with 2000 for a satin finish. Toothpaste on a 2000 satin finish will get you a mirror polish with just rubbing a small amount with a paper towel. Your flesh ...

Has anybody ever tried frankensteining a BTC 5100 and 5100C together with Topre springs and domes? Worst case you'd have to hook up a xwhatsit controller for the right voltage settings if the switching is borked with the original 5100 controller. That would dead 100% allow the most direct comparison...

It might be that the controller firmware switch rest position wasn't reversed by mistake. Run the voltage up to like 115 where everything is actuated and try pressing some keys and see if any of the squares goes white.

Auto voltage just plain doesn't work that I've seen, so I wouldn't bother with it.

Have you opened up the board module and cleaned between the PCB and the switches and all that? Cause it just takes a few little chunks of stuff to get down in there and cause chatter. 107 also seems a little low. I had to set mine around 138 I think. You should have a couple reference pads show up a...

JP!, you pretty much nailed it. The only thing I'd add is that I had to increase my thresholds a few millivolts once I connected solenoid boards to kill chatter. Something about the current pulse through the controller I think. Oh, and that the reference pads will show up as depressed as soon as you...

3278 with a little remapping is pretty perfect. You just set the numpad/function cluster as a standard nav cluster in one of the layers and bottom keys to modifiers. Then you can also set the block nav to media and volume controls in that layer too. :D The only thing you really miss out of habit is ...

You can just use a sponge or wet cloth to keep from getting water on the card. You don't need to submerge the whole thing.

This is 100% the right material and the right thickness to replicate the original feel. The trick is how to get enough slack around the switches without molding. Probably could do it with an extra large sheet and scrunching it up a row at a time. But with that much free material wadded up, it might ...

Got a replacement contamination shield made of extremely thin silicone rubber, same thickness as the original vulcanized rubber. It works but it completely sucks. The keys are a good 30g heavier and you literally see them pull toward each other when you press a key. Looking at the original shield, I...

I love these videos. The reviews are great, but the teardowns and switch history ones are the best.

Awesome project. A really clever bit of restomodding.

One last update. Tightened up the throw a little on the solenoid I added and got a few of the original 70's LED's up and running to show when the keyboard is connected to the computer and that the solenoid is powered up (system available and online). Then I hooked a third up to input so it flashes e...

Yep, just plugs right in.

xwhatsit compatible solenoids for $10 Found a good replacement for the standard beamspring/model F/model C solenoid that's cheap and works perfectly with a couple minor mods. Best first thing about it is that it has an adjustable throw. Default is around 4mm or 5mm. But with a couple minutes with a ...

I went ahead and made a small picture of how the capacitive leaf switches in this thing work for the curious. Sorry I wouldn't tear it open a third time but it's crazy how careful you have to be to not bend these the wrong way with them just naked on the board.

Got the keys all clean for the most part. I wiped them down by hand since I was worried some of the paint on the engraved bits might wash out. You can get a good look at the extra symbols now. The xwhatsit controller is also coming in today so I'm looking forward to firing it up. http://i.imgur.com/...

Thanks for the nice comments and info guys. For the engraved symbols, just seems like extra layers for mathematical shortcuts like on some other terminal keyboards. Seems Alt+Key for front red and Alt+Shift+Key for the top red. Haven't quite figured out the way to get the fifth symbol on some keys t...

PM the seller. I think when I bought mine he mentioned that he had the CRT's for it too, just didn't list them because the shipping would be so high. Smarts are bottom board and has a piezo buzzer and speaker that took too much juice to run straight off the controller card unfortunately. There's a t...

I think there's one up right now from the guy I got mine from. I think he mistakenly listed it as a 1977 though. Also, I really don't want to pull the board apart again to get closeup shots of the leafs because they're so delicate, one wrong brush of a hand and you can bend them out of line. But thi...

This is a bit of an unknown to me, and I was hoping somebody has seen one of these before. I got a heck of a deal the other day, and picked up a load of old IBM mainframe equipment for less than twenty bucks. This included this 3178-2A Terminal, local controller, remote controller, and more. Not sur...

I posted this project originally on geekhack but I thought it would be good to post it here as well since it's a pretty uncommon board and I haven't seen this specific switch on the wiki. This is an old Harris board from the first year after they bought out Sanders. Earlier boards of this series use...

My main worry would be the heat causing some delamination bubbles in the PCB, more than actually destroying anything because these things are pretty old. Just cosmetic but still makes you feel bad. I was lucky that didn't happen when I had to pull stuff on my old Harris terminal to get it to hook up...