RF gain/AGC issue

[Dan in Florida]

I just performed an experiment on 40 and 20 meters.

I found a CW signal.

I turned the AF gain all the way up, and the RF gain all the way down.

Then, I turned the RF gain up slowly, with AGC on, and then AGC off.

With AGC off, as the RF gain was advanced, I heard the signal well in
advance of hearing the noise.

With the AGC on, as the RF gain was advance, I heard the noise well in
advance of hearing the signal.

I repeated this test on many signals, with the same results.

Dan- W4TQ
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[David Gilbert]

What were your various AGC settings?  Also, what bandwidth were you using?

73,
Dave   AB7E



------Original Mail------
From: "Dan & Jean" <[hidden email]>
To: <[hidden email]>
Sent: Tue, 2 Feb 2010 16:08:30 -0500
Subject: [Elecraft] RF gain/AGC issue

I just performed an experiment on 40 and 20 meters.

I found a CW signal.

I turned the AF gain all the way up, and the RF gain all the way down.

Then, I turned the RF gain up slowly, with AGC on, and then AGC off.

With AGC off, as the RF gain was advanced, I heard the signal well in
advance of hearing the noise.

With the AGC on, as the RF gain was advance, I heard the noise well in
advance of hearing the signal.

I repeated this test on many signals, with the same results.

Dan- W4TQ
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[Guy, K2AV]

Were you using slow or fast AGC? Were PRE or ATT on?  Was either NB or
NR engaged?  If so what were the settings?  From your config menu,
what are the settings for AGC-S, AGC-F, AGC THR, AGC SLP, AGC PLS, AGC
HLD, AGC DCY?  Were you listening to the CW signal in CW mode? If not
what mode?  What was the WIDTH setting?

73, Guy.

On Tue, Feb 2, 2010 at 4:08 PM, Dan & Jean <[hidden email]> wrote:

> I just performed an experiment on 40 and 20 meters.
>
> I found a CW signal.
>
> I turned the AF gain all the way up, and the RF gain all the way down.
>
> Then, I turned the RF gain up slowly, with AGC on, and then AGC off.
>
> With AGC off, as the RF gain was advanced, I heard the signal well in
> advance of hearing the noise.
>
> With the AGC on, as the RF gain was advance, I heard the noise well in
> advance of hearing the signal.
>
> I repeated this test on many signals, with the same results.
>
> Dan- W4TQ

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