Mike,
Thanks for the heads-up. I was not aware that this was the case.
In 1964, I designed and built a hybrid 20m SSB/CW transceiver in which the
AGC was audio-derived. I considered placing a narrow audio filter in the
receive audio signal path for CW, but never got around to it.
Cheers for now, 73,
Adam VA7OJ/AB4OJ
-----Original Message-----
From: Mike Hyder -N4NT- [mailto:n4nt@charter.net]
Sent: October 28, 2002 12:41
To: Adam Farson
Subject: Re: [TenTec] Receivability
The Ten-Tec audio filters are inside the AGC loop.
Mike N4NT
----- Original Message -----
From: "Adam Farson" <farson@shaw.ca>
To: "Ten-Tec Contesting" <tentec@contesting.com>
Sent: Monday, October 28, 2002 1:30 PM
Subject: RE: [TenTec] Receivability
Mike,
The IF filters do something which post-AGC audio filters can never do. As
they are inside the AGC loop, IF filters remove strong interfering signals
from the IF chain before they reach the AGC detector. As a result, AGC
pumping (receiver swamping) is avoided.
A combination of IF and audio filters is a good choice when receiving a weak
CW signal in the presence of strong adjacent-channel interference.
Best 73,
Adam, VA7OJ/AB4OJ
North Vancouver, BC, Canada
http://www.qsl.net/ab4oj/
-----Original Message-----
From: tentec-admin@contesting.com [mailto:tentec-admin@contesting.com]On
Behalf Of Mike Hyder -N4NT-
Sent: Monday, October 28, 2002 07:53
To: Scanandoah, Alan
Cc: Ten-Tec Reflector
Subject: Re: [TenTec] Receivability
Hi, Al--
I find the same thing on CW. Audio with very low distortion makes my ears
better able to sort things out. For that reason, I prefer the older radios
like the Triton, old Omni's and 580 Delta to newer ones. I even like using
those older rigs better than my Corsair II. In addition, I can listen to
one of the older rigs for hours without becoming tired.
But I have not owned an Omni V or VI, so my comparisons are only with a
couple of Japanese rigs. I did listen to a friend's Omni V and thought it
had good audio, but I've never even seen an Omni VI.
Based on my experiences over the years, I find that the clarity of the audio
is more important to me than the selectivity of the radio is. Apparently
many folks feel they need very narrow filters but I usually prefer to use
just the audio CW filters in the rigs.
73, Mike N4NT
----- Original Message -----
From: "Scanandoah, Alan" <ascanand@harris.com>
To: <tentec@contesting.com>
Sent: Monday, October 28, 2002 9:25 AM
Subject: [TenTec] Receivability
Over the weekend, I handed out a few random points for CQWW. Not being much
of
an SSB op, I found the wall-to-wall cacophony to be difficult to deal with.
This prompted me to do some A/B checks to see if one rig could hear better
than
another; I compared my Omni V to my Omni A. Surprisingly, even though the
Omni
A is lacking in the IF selectivity department, I found it much easier to
pick
out signals. The overall product at the speaker just seemed to be much more
readable.
Has anyone else had similar experiences?
73 - Al, K2ZN
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