[Elecraft] K3 AGC and Apparent Noise and Signal Distortion

[Wes Stewart]

Rob and I are in agreement on the AGC thing.  I believe Wayne has said much the same.

When high-end receivers had two pentode -r-f stages driving a pentagrid mixer and barn door selectivity, it made sense to reduce the r-f gain.

IMHO, riding the r-f gain control (really i-f gain in the K3) in a properly designed receiver should be totally unnecessary.

If it necessary, then the "properly-designed" nomenclature doesn't apply, except in the rarest of circumstances.

Furthermore, unless you've done the r-f gain calibration in your K3, reducing the r-f (i-f) gain with AGC on might severely degrade the SNR.

Fire at will.

Wes  N7WS


--- On Wed, 2/3/10, Bill W4ZV <btippett at alum.mit.edu> wrote:

FYI here's a note I got from Rob Sherwood NC0B regarding his experience with
the K3 in the CQ 160 last weekend. 

I did post a comment on how the K3 performed.  Using 40 ohm per channel
stereo headphones, I was not bothered by any audio distortion issues.  I ran
the AGC the whole time, and noted no problems.  I am not into the RF gain
back and the audio up method.   I have the AGC setting on SOFT, an option
that came out last summer I believe.