[Elecraft] K2 no receive . . . where to start?

[Mike Geddes]

Finishing up K2 6042 today.  Have fine output on all bands, but no receive!  I did use another HF rig to create signal for alignment . . . and I did hear that.  I can also hear SPOT, so think amp is okay. But nothing from antenna. For reference, I connected my K1 to same antenna and receive was fine.  I checked voltage at anode of D6 on the K2 and it is fine.  Not sure where to go from here. Any suggestions?

Thanks and  73,
Mike
N4JX

K1/4  2319 on the air
K2/100  6042 under construction!