[Elecraft] K4 S-meter characteristics

[Greg Troxel]

Wayne Burdick <n6kr at elecraft.com> writes:

Thanks for the note.  I am a fan of radios being able to serve as test
equipment, when that's a reasonable approach.

> In addition to the S-meters, the K4 provides a convenient way to see
> signal levels directly in dB (relative). Typically you'd zero the
> reference level on band noise, then tune into a signal to get the dB
> increase (S+N / N). This is useful for comparison tests. The numeric
> values for dB, both main and sub, are shown in the status area of the
> display, so they don't overwrite VFO B as on the K3/K3S.

I am not sure how popular this request will be, but I would like to be
able to see signal levels in dBm.  Given what you said, that's just a
different labeling, similar to how the PX3 can label in dBm or S units.
But without seeing it, I realize that it could be awkward to have lots
of large negative numbers, and if "S1" really means -73 - 8 * 6 = -121
dBm, as it seems to on the PX3, there's no real need.  Probably, it's
enough to see this in the "P4" section, and to use the SHM interface
command.

I think you are intending to stick to -73 dBm for 6m as well.  There is
a notion of using 5 uV for VHF, but I think that's more confusing than
helpful, so I am in favor of -73 dBm for S9 always.

It would also be nice for the KX3 to finally get the long-discussed
absolute S-meter mode.

73 de n1dam