[Elecraft] K3 Transmitter Gain Calibration Problem

[Joseph M. Durnal]

I'm building the K3 and getting near the end (hopefully).  When I
follow the transmitter gain procedures, it displays ERR TXF over VFO
B.  The watt meter showed that it was putting out 5 watts, but the
error message worries me.  Any ideas?

Thanks,
Joe