The RF board of the K2 is the most daunting part of the build. It has the most components to install, and also requires the precise winding of quite a few toroid inductors, which I've never done. A lot of people seem to quiver in fear of winding toroids, but everyone I know who has done it says that it's really not that hard. The important part is to just take your time and keep an accurate count. I had the option to pay extra for pre-wound toroids for the K2, but I decided to man up and do it myself.
As of now I have finished phase one (of three) of the RF board assembly. At this point you get to put the RF board together with the front panel and control boards, power it all up and do some testing. At this stage we make sure the relays and rotary encoder are working, we test the audio amplifier and tone generator, we try out the keyer, we set the AGC threshold and align the S-meter, and we make sure the S-meter is drawing the right amount of current. The toroid winding starts in phase 2. Here are the pictures of my progress so far:
Latching relays, a socket, and spacers (on the bottom) installed.
Keyer and headphone jacks, antenna connector, power switch, header pin sockets, and various other components installed.
Side panels attached.
Now it REALLY starts to look like a radio!
The K2 includes a built-in frequency counter for testing. We assemble its probe and test it out at this point. Phase 2 of the RF board starts tomorrow, I hope!