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

[John Chappell G3XRJ]

Don,

What I should have mentioned in my initial post was that the recording
was made at midday on 80m and the noise from the antenna was only s1.
For a given setting of the rf gain, increasing the threshold to 8 
increases the noise, as can be heard in the recording.

John G3XRJ

>
> 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
>
>