Elektronika MK-61 - today I ordered one NIB

[voltaage]

(12-09-2021 10:21 PM)HP67 Wrote:  Thank you! I should find some sponge and fix a few of my Elektronikas.

Wish you the most sucess! Plastic clips on these calculators are not to be trusted. When you think they'll flex out enough, they just snap off. I can anticipate that the search for that sponge will take long. After replacing the one on the keyboard... Why not having an extra bit around for the future? - I said to myself - I can only say that I'm still looking for that 0.5 cm sponge sheet. It sometimes too thick or not "spongy" enough. Good that I still have a bit left of the one in that frame.



Quick annotation regarding the keyboard assemby:

The plastic mat's traces on my MK61 are made out of some sort of carbon paste similar to the one often found in tv remote controls. This one I often see it fades out or tears apart with use/age. Mine's all right. I've seen some pictures of the MK52 having the traces made out of flat wire, like the IBM Model M. Seems that some of the MK61's were made like this, but very little is known from those variants. A very durable keyswitch option: metal vs metal instead of metal vs carbon paste. Not to be confused with the very early variants that have a tactile metal dome array, like in many of the HP's. Ultimate durability. But this is doomed if you want to change the sponge retaining the keys, since the black cover is plastic-riveted. Tic-Tac(TM) inside guaranteed.