[Elecraft] Internal K2/K3 S-meter resolution for computer recording?

[Lyle Johnson]

> So, the question is:  How much internal resolution of the S-meter reading do
> we have in the K2 or K3 (or other Elecraft rigs, for that matter), that
> could be read by a computer?

You can go one better with the K3.  It has an internal dBV output which 
is based on a true RMS voltmeter function.  This will eventually be 
readable by software.  So, you set things up, perform an "AFV" (AF 
voltage, not affected by the AF Gain control, fortunately) measurement 
to get your reference level, then switch to dBV and see it is around 0.0 
(with some bobble due to noise, etc.) Now increase or decrease the Tx 
output of the thing you are measuring (or swing the beam, or...) and get 
the result in dBV referenced to the first measurement.

As long as the S/N is reasonable, you can measure over a pretty wide 
range of signals.

Of course, you'll want to have AGC off when you make this sort of 
measurement so the AGC compression doesn't affect the AF voltage.

And, yes, since it is an AF voltmeter, you can use this to measure 
insertion loss of filters, effectiveness of notch, etc.

Enjoy!

Lyle KK7P