I suppose you folks ought to make a note as to _which_ rotary encoder is (1) wearing out, and (2) being purchased as a replacement.

The Mk2 and Mk2a used different encoders, and different means of soldering them to the displayboards. I think.

I still have a small number of spare Mk2 encoders at home, for the cost of postage to needy BBS members.

Cheers