[Elecraft] K3 dbV in 2.38

[Eric Swartz WA6HHQ - Elecraft]

Hi Brian,

The dBV and AFV functions were designed primarily for use with steady 
state lab signals to test receiver sensitivity etc. We added these two 
displays to speed our final test of the K3 in production, and as an aid 
to do this in the field with simple tools like our XG2 test oscillator. 
They were not intended for dynamic signal, off the air measurements.

73, Eric  WA6HHQ
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_..._



alsopb wrote:
> Apparently I need some help in trying to use this dBV capability with on the
> air signals.
>
> For example, using it as an AGC off "relative" S-meter with digital readout
> to run some antenna pattern checks for skewness etc.
>
> I've used it just fine in "lab type" measurements with a constant signal
> source.
>
> First question.  What is meant by stable value of AFV?
>
> Here's what I see for a bunch of AFV edited values one after another with no
> change in K3 settings.
> 1579,1688,1598,1624,1696,1613, 2168,1758,1425.
> The range is 6db.  
>
> Is the reference value of AFV used in the dbV calculation the last one taken
> at the instant one leaves the menu entry?  Yes, it doesn't really matter if
> that values is used forever.
>
> Suppose one then takes a series of dbV measurements,  is the reference AFV
> ever changed during the set of readings?
>
> The integration times available are 500 and 1000 ms.  It would seem that
> longer integration times are required for off air type measurements.
>
> Is there any integration time in the measured voltage used in the dBV
> calculation?  Or is it nearly an instantaneous value?  For off the air type
> measurements, it would seem that a suitably long value is needed.
>
> 73 de Brian/K3KO
>