I don't know what level QRN crashes add to the general noise level: it
would be interesting to know what difference the roofing filters add to the
dsp filter in these condx.
David
G3UNA
The local noise level on 80 shows up as anywhere up to S7or 8.
With ATT ON, it still shows on the meter, but is nothing like as
aggressive.
On SSB I use the stock filter and leave other things alone most of the
time.
Two things:
First: ATT drops the noise and apparently (it must be a bit of an
illusion)
leaves the signal. It seems that ATT ON limits the peak effect of noise
crashes. Not very scientific, I'm afraid. You just play and see whats best
at
the time !
Second: AGC OFF results in a significant drop in strength of everything.
This
is not what I am used to, so I have AGC ON all the time, usually set to
FAST,
but there can be a problem with if there is a strong signal on frequency.
The
transition from TX to RX and vice versa can be marked by loud pops and/or
clicks. I believe this is to do with the way the DSP and AGC systems
respond
and I understand, very much off record, that a mod for the AGC behaviour
is
in the works.
In fact I suspect it is already in current production K3s, like another
mod
to fix a keying characteristic glitch in an early batch where an
overly-large
capacitor was installed in error. I did that mod myself.
If I ever get the info (and parts) I will do the AGC mod and see how it
goes,
but the general advice I got was to "leave well alone unless you are sure
you
need the mod !"
Marvellous radio; the best receiver I have had, even better than my
much-modified TenTec Omni-5. But better antennas would help.
and I'm adding a 200Hz roofing filter when I get one.
73 John G3JAG
On Saturday 23 February 2008 11:25:25 you wrote:
What noise levels were you receiving? It would be interesting to know
what
they were before and after you selected filters, but you were probably so
amazed with your contacts withVP6DX that sort of stuff went out of the
window : o )
Do you operate with or without AGC, full rf gain? Sorry for the 3rd
degree, just getting a handle on real band condx with weak signal
reception
: o / I will be severely limited on antennas as well.
David
G3UNA
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