|Honeywell encoder shaved to fit|
Seeing that I was going to have some challenging mods to make to get this to work, I first made a promise to myself that under no circumstances was I to modify the K2 itself. All modifications had to be to the part. That way, if I did get stuck I could always be sure that the original K2 encoder would fit again.
|Encoder mounted on rear of FP board|
|New encoder mounted to FP board|
Up to this point I'd been pretty lucky. There was room to spare between the back of the encoder and the Control Board behind it, so no worries there. There are a couple small spaces in the square FP hole to route the encoder wires to the front pads. Of course, I'd already put in the new FP U3 and temporarily wired the encoder so that I knew this was all going to work electronically.
|Extending the tuning shaft|
I first tried simply gluing on a short piece of steel rod. The only metal-to-metal glue I could find in town though was epoxy and it wasn't up to the job because of the tuning knob weight. I considered welding on the extension, but even if I had wrapped the encoder in a rag drenched in ice water I doubt I could have done that that without damaging the electronics.
|Extension with plastic shim|
I think this is a permanent fix and no mods to the K2 chassis itself were made. It took a little adjustment of the tuning knob to get it to turn without wobble, but that wasn't much to overcome in the end.
The radio now works FB, the only change being that it tunes slightly faster since this encoder part is 128 PPR (Pulses Per Revolution) whereas the original encoder was 100 PPR. I think I can consider that an improvement! It was a fun project and saved me 60 bux over buying a new encoder from Elecraft.
Please share your experiences with homebrewing a radio equipment repair in the comments!