[Elecraft] Err TXF on 7.077

[David Ferrington, M0XDF]

I just tried to make my first QSO (s/n 174 K3/100) - I get ERR TXF when
trying to transmit on 7.077 LSB at 5.0w using Proset K2, via AD-1-K adapter
into front connector with Mic Sel set to FP.L Bias

Selecting bypass ATU and TUNE to my SG-237  appears to work ok, an ext.
Watt/SWR meter shows it transmitting and the SGC tunes ok.

Must be something I'm doing, but haven't the faintest what it is
-- 
If all is not lost, where is it?