[Elecraft] K3 ESSB transmit now allowed with the FM filter (firmware rev 4.60)

[Wayne Burdick]

I've modified the K3 software to allow use of the FM filter for ESSB  
transmit. (The current beta release, 4.58, already allows AM transmit  
with the FM filter.)

The AM filter (6 kHz BW) is still a much better choice for AM and ESSB  
receive, because it provides better close-in dynamic range. But it  
turns out that the difference between the two filters is fairly minor  
in transmit. I have a new Rigol spectrum analyzer which made it easy  
to do a detailed survey at both narrow and wide spacings.

If you're interested in testing the new field-test release (4.60),  
please email me directly.

73,
Wayne
N6KR