deskthority

Forgive me, I just woke up from a stupidly long nap a couple minutes ago and had an epiphany.

Who said the hall effect should only be used for smooth linears. The sensors work in game controller shoulder buttons and probably anything else. What's a plentiful keyboard with great feel that lacks NKRO?

Hall effect model M. Just attach a magnet under each stem/keycap and get a new PCB to to the underside of the case, under the original barrel assembly.

Easy NKRO with no impact on keyfeel and no need to bolt mod or flippers.

Anyone know how to make a hall effect PCB?

Edit: An F to M mod is probably a better way to convert an M given fitting a new PCB would probably require taking the barrel assembly apart anyway.
Anyone know of an easy to find foam and foil board that would benefit from a hall effect modification?

While I commend the idea, I have always thought that the major ingenuity of the Model M/F was that it had a simple switch mechanism in which the tactile event, the click and the actuation were intrinsically linked 1-to-1.

It sounds like a fun project, but you would lose that intrinsic coupling.
The Model F - being capacitive - has NKRO, as I'm sure you know

If you wanted an M with higher KRO you'd have better luck with expanding the matrix, which is exactly what Unicomp has done with their latest offerings (the mini, and I believe their new M classic has it too). Or diodes.

It's been discussed before.

viewtopic.php?t=6763

I'm starting to think a foam and foil board might be a better candidate for a hall effect mod. Any suggestions?

E TwentyNine wrote: 11 May 2021, 12:10 If you wanted an M with higher KRO you'd have better luck with expanding the matrix, which is exactly what Unicomp has done with their latest offerings (the mini, and I believe their new M classic has it too).

Just the Mini, unfortunately. I'm guessing something to do with the Mini having fewer keys allowed some jiggerypokery, and I've heard it causes some weirdness so perhaps I shouldn't be too sad about not having it on the full size. My New Model M appears to have essentially the same matrix as an original Enhanced Keyboard just with the three additional bottom row keys (and they messed up the Pause/Break key on the PS/2 controller somewhere along the line but that's a slightly different matter).

Rayndalf wrote: 11 May 2021, 12:26 I'm starting to think a foam and foil board might be a better candidate for a hall effect mod. Any suggestions?

Foam and foil conversion to buckling spring?

I know very little about hall effect sensors, but to me the benefits of hall effect over other switches are NKRO, potential big smoothness (no contacts or moving parts), analog sensing (with the right controller), and long life (no contacts or moving parts to wear or oxidise). I would expect their main disadvantage is complexity, especially when for analog switches.

As a switch, foam and foil (assuming KT as it's the most common) is... not as bad as the most vocal members of the community would have the rest of us believe, even in its low profile variant. When the foam disintegrates and it looses the sponginess at the bottom, it's actually decent, and I suppose hall effect sensing would leverage that. However, it already has NKRO. Smoothness isn't one of its strengths either, and I would imagine you'd want a smooth base switch to get the most out of a HE mod. It's also already contactless, so it's not going to get any smoother. Removing the foam would fix F&F's biggest flaw though - it's durability.

So, a HE mod on F&F would give you a bit better feel, and a greatly improved durability, at the cost of a new hall effect PCB and controller. It would be very cool, but my feel is given the benefits, it's probably too niche to gain much traction, especially considering the general negative reputation F&F boards have, and the fact that a protocol conversion or controller swap via Commonsense is likely less effort for most people.

I do love these sort of mods though, and I really liked your original idea. My original dumb comment wasn't totally baseless either. I think the capacitive PCBs are the most interesting part of F&F switches, and I've got two lovely capacitive PCBs sitting next to me doing nothing. Forgive me for knocking your idea then raising a worse one of my own, but wouldn't it be nice if we could bend a Keytronic PCB against a model M barrel plate with some model F flippers and get ourselves a 101 key capacitive buckling spring board... obviously it would make sense to get a new PCB, but then what am I supposed to do with these Keytronic remains.

Edit: Regarding a hall effect mod, I think the best candidate would certainly be an interesting, common and well built rubber dome board. Most rubber domes are pretty smooth (to the point I almost had an existential crisis after finding that the smoothest used Alps board I could find was much scratchier than most generic dome boards), and no one wants them. How about rubber dome unsavers, or even something like those pretty HP boards - viewtopic.php?t=18339.

4_404 wrote: 11 May 2021, 13:35 Edit: Regarding a hall effect mod, I think the best candidate would certainly be an interesting, common and well built rubber dome board. Most rubber domes are pretty smooth (to the point I almost had an existential crisis after finding that the smoothest used Alps board I could find was much scratchier than most generic dome boards), and no one wants them. How about rubber dome unsavers, or even something like those pretty HP boards - viewtopic.php?t=18339.

This is all good information. If I'm honest I didn't realize foam and foil boards were capacitive until a few hours ago. Foam and foil gets a lot of hate, but replacing the foam (meant to dampen post actuation switch travel?) with something denser and maybe a little thinner might make keytravel sharper without dramatically increasing the actuation distance.

I think I need to give foam and foil an honest try before I modify it which should be pretty easy since most people (like me a few hours ago) completely discount it like a mushy rubberdome with inconsistent keyfeel/weighting across the board and 2KRO.

As for dome boards, many already have holes in the stems for magnets and many have more modern layouts and good keycaps with good price/availability.

I don't know how to design my own PCB let alone a hall effect one (I assume the sensors are SMD and somewhat expensive), but I have a whole summer to figure it out. A lot of the "good" boards are getting expensive, so it'd be really to save some otherwise good boards from the trash.

I just remembered I have a PCjr board in desperate need of help too.