[Elecraft] a question to Wayne Burdick - K3S if gain

[Bob Wilson, N6TV]

On Sun, Jul 8, 2018 at 4:49 AM, IK4EWX <glcazzola at alice.it> wrote:

> On my Elecraft K3S, sn 10715, the if gain, or better the FLx GN, was setted
> 0 for FL1 (2700hz-5 pole),
> 4 for FL2 (500hz-5 pole) and 8 for FL3 (200hz-5 pole).
> I read somewhere that it would be better 0 for wide filter, 2dB for medium
> filter, 4 dB for narrow filter.
>

The K3 manual provides 0/2/4 as suggested values.  The filters in your
radio, as determined by the factory calibration procedure, must have needed
more gain.

What is better Wayne? Can I use on my great K3S 0dB-2dB-4dB? Or you prefer
> other settings?
>

You can change the Flx gain values and hear the sensitivity of each filter
go up and down.  Ideally, signal strength should not change as you switch
between filters.  The K3 Utility provides an RF Gain calibration procedure
too (requires a signal generator).


> Sometime I like to use my old Cubic Astro 102BXA, yesterday on 10 meters,
> with a bug.
> How can be that this rig, 35 years old, have the best agc and a great qsk
> even for today standards?
>

How can one define "best AGC?"  Define "more pleasant."  Maybe you can post
an audio recording made from the headphone jack with an isolation
transformer so that we can hear what you're hearing.

Have you tried changing the K3's AGC settings from the factory defaults to
the values recommended here
<http://elecraft.365791.n2.nabble.com/K3-Receiver-mush-tp7627277p7627323.html>
?

As for QSK, T/R turnaround time is probably better in the Swan rig because
it doesn't have any digital signal processing, so no latency added, so no
delays waiting for buffers to fill before the receiver hears signals
between elements.  But no DSP means limited noise reduction, limited notch
controls, no adjustable noise blanker, etc.  You can't have everything.

73,
Bob, N6TV