Canon S-51 typewriter (SMK "peerless"?)
Posted: 28 Sep 2018, 19:45
I found a cheap-looking electronic typewriter at a flea market for €5. The keycaps were nice though and I liked the key feel so I bought it without looking further. And when I got home, I took it apart ...
Keyboard: We have seen other other Canon typewriters, but with Alps stems and switches. This keyboard however, has two other types of switches that I have not seen before. Also, the keycaps are cylindrical, not spherical... except for the ones on either side of the space bar which are flat.
The full-size keys have a discrete integrated slider-over-spring-over-conductive rubber dome-over-PCB switch, whereas I think the smaller buttons are merely discrete integrated domes.
PCB Apparently, this keyboard was made by SMK. And like some verified SMK switches, these switch modules have no markings other than a digit or letter, probably indicating position in the injection-mould parts tree.
The LCD screen 's PCB is attached to the top of the plate, with passthrough to the keyboard PCB which has a ribbon cable to the typewriter's main PCB. In each switch's bottom, there is a dome, and ...
Large switch ... inside the top of a larger switch module, I can just see that there is a coiled spring in there.
I have not found a way to take these modules apart, yet ...
The large switches are light and clicky, with a very light sound that got louder after I had unscrewed the PCB-plate assembly. The switches feel linear up to the click point at which resistance drops off and the dome inside juts forward.
So, this is most likely similar to the Fujitsu Peerless mechanism — but I would dare say, better, as these are light and stable. No key felt the least scratchy on a off-centre key press but then I got this in good condition.
With my measly calipers I measured total key travel at 4 mm and (slow) travel to actuation to ~2.5 mm.
I do suspect that (as Peerless switches), the actuation distance could vary with typing speed.
They bottom out soft and distinct, like good rubber domes (such as Topre, BTC etc).
The stabilisers are nice too. Hinged inside the keycap and the clips in the plate have ramps that guide the stabiliser wire into the right position when you install it. A much better solution than Costar-style or Alps stabilisers IMHO.
Small switch The smaller switch has a slider that covers the top of the switch: the entire top presses down and only a short amount.
The mount is not Cherry MX-compatible BTW. These can also have stabilisers.
Anyone seen these before? I quite like the larger switches. Clicky but quiet.
Keyboard: We have seen other other Canon typewriters, but with Alps stems and switches. This keyboard however, has two other types of switches that I have not seen before. Also, the keycaps are cylindrical, not spherical... except for the ones on either side of the space bar which are flat.
The full-size keys have a discrete integrated slider-over-spring-over-conductive rubber dome-over-PCB switch, whereas I think the smaller buttons are merely discrete integrated domes.
PCB Apparently, this keyboard was made by SMK. And like some verified SMK switches, these switch modules have no markings other than a digit or letter, probably indicating position in the injection-mould parts tree.
The LCD screen 's PCB is attached to the top of the plate, with passthrough to the keyboard PCB which has a ribbon cable to the typewriter's main PCB. In each switch's bottom, there is a dome, and ...
Large switch ... inside the top of a larger switch module, I can just see that there is a coiled spring in there.
I have not found a way to take these modules apart, yet ...
The large switches are light and clicky, with a very light sound that got louder after I had unscrewed the PCB-plate assembly. The switches feel linear up to the click point at which resistance drops off and the dome inside juts forward.
So, this is most likely similar to the Fujitsu Peerless mechanism — but I would dare say, better, as these are light and stable. No key felt the least scratchy on a off-centre key press but then I got this in good condition.
With my measly calipers I measured total key travel at 4 mm and (slow) travel to actuation to ~2.5 mm.
I do suspect that (as Peerless switches), the actuation distance could vary with typing speed.
They bottom out soft and distinct, like good rubber domes (such as Topre, BTC etc).
The stabilisers are nice too. Hinged inside the keycap and the clips in the plate have ramps that guide the stabiliser wire into the right position when you install it. A much better solution than Costar-style or Alps stabilisers IMHO.
Small switch The smaller switch has a slider that covers the top of the switch: the entire top presses down and only a short amount.
The mount is not Cherry MX-compatible BTW. These can also have stabilisers.
Anyone seen these before? I quite like the larger switches. Clicky but quiet.