KBK update for Sunday, 3rd July
“fricked” has found the first example of a wired inductive Licon keyboard, part number 55-000084, listed for sale on eBay for a paltry $599.99. This example is the type described in US patent 3714611A and, from the part number, will be a low-profile Series 550 keyboard, and the first Series 550 keyboard ever seen. Strangely, despite the use of encoding switches, the logic board is the same size as the keyboard itself, with a total of 49 logic chips! Unfortunately eBay photos are too small to allow anyone to read off the chip codes. (See the ITW page for a link to the eBay listing, since at some point it will die and–as whoever is buying all these rare items squanders them and they vanish without a trace—the link will have to be replaced with one pointing to my archived photos as the only thing keep alive the item’s existence.)
The model I forgot to archive the photos from (55-100007, which the new owner has predictably kept hidden from the world) was probably an original Super Switch keyboard, considering that the switches were soldered to a PCB instead of threaded. Conceivably these PCB-mounted models were created to allow matrix wiring and thus N-key rollover, and may have been classified as Series 551.
The switches in 55-000084 are a lot like the “Style A” switches from Series 555, which implies that the patents filed in 1973 for tactile feel and alternate action were more likely intended for either Series 550 low profile or Super Switch. (The patents, uncharacteristically, omit the details of the switch itself.)
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