[Elecraft] K3 AGC THR doesn't go low enough

[Don Wilhelm]

  Steve,

The solution is to RAISE the threshold.  I run mine at 008 which is the 
max.  I also run the slope at 002 which makes the K3 AGC response more 
like my K2 - weak signals sound weaker than stronger signals.  You can 
alter the slope without running into the situation where the K3 sounds 
noisy, but the signals will sound more nearly the same as the slope 
numbers get larger.

If your local noise is high, increase the AGC threshold and the K3 will 
quiet down.
There is yet another way - turn off the preamp, and even turn on the 
attenuator.  You will have to increase your normal AF Gain a bit, but 
the noise will be reduced.  If you can still hear an increase in the 
audio output when the antenna is connected, you can even reduce the RF 
gain.  You are not increasing the USABLE receiver sensitivity by running 
everything at full right controls  - in the presence of atmospheric 
noise, that will only reduce the usable dynamic range and will make the 
receiver sound noisy.

73,
Don W3FPR

On 10/8/2010 10:25 AM, Steve Wedge wrote:
> John, I've noticed the same thing: the AGC does seem to make the receiver - in the absence of signals - roar quite a bit with my early (#770) K3.
>
> I've attributed a lot of the noise to computer and suburban hash, but listening with my old Drake receiver shows things much quieter.  Noise reduction does help, but it would be nice to quiet this down as John suggests.
>
> My .02
>
> Steve, W1ES
>