[Elecraft] AGC & DSP Rain Dance

[Gary and Kathleen Pearse]

I've experimented almost daily during the last two Winter seasons  
searching 160M CW signals and making a few contacts. Not S9+, not  
loud and crowded Contesting or operating EU from the East Coast of  
NA, but typically weak signals from the middle of KL7.

I'm under the Aurora's influence in a typical S5-7 city noise floor,  
even with 100-150Hz filters enabled and all of the K3's arsenal  
brought to bear. It's typically S9+10-15 at 2.4 KHz for me. I have an  
Inv-L up 70'/out 55' with seven tuned elevated radials, and a  
rotatable Wellbrook receiving loop located on a 120x120' city lot  
surrounded by three power distribution lines. Yea I know - move.

If I only used AGC-on to hear the weak I may as well find another  
hobby. ATT on, RF (IF) gain up or down, doesn't matter. Threshold 08,  
Slope 000, filter gain up or down, doesn't matter. If the AGC (S or  
F) is used, the weak blend into the noise floor. I typically listen  
at a 450-500Hz tone.

However, if I turn the AGC off I can usually fine tune the AF and RF  
levels well enough hear, and usually work all heard. On 160M I've yet  
to hear as well with the AGC enabled as with it off.

Loud signals well out of my noise floor and on higher bands are  
another matter.

73, Gary NL7Y