Actually, in my Argosy the audio filter was inside the AGC loop. In my
Argosy II, sad to say, the audio filter came after the AGC sampling point so
wasn't nearly as good. Never did understand why Ten-Tec did that.
Mike N4NT
----- Original Message -----
From: <n8coo@juno.com>
To: <farson@shaw.ca>
Cc: <tentec@contesting.com>
Sent: Monday, October 28, 2002 4:30 PM
Subject: Re:RE: [TenTec] Receivability
At least on the Argosy, (and I suspect some other Ten Tec rigs were the
same) the AGC was audio derived, and the (optional on the Argosy)) internal
audio filter worked inside of the AGC loop. Ten Tec made it a point to
mention that in their manual as a feature they had compared to other some
other units. I agree the (again optional) narrow CW crystal filter would
help further.
While I'm here, I really like CW & digital on my Paragon. And you can use
the 500 or 250 Hz filters, slide the passband around where you want it with
the PBT, then dial in the built-in audio filter to cut out the noise. The
nice thing is, the audio filter doesn't affect the fixed-level audio out for
my sound card interface (in case I forgot to open it back up). Incidentally
the audio filter is outside the AGC loop on the Paragon.
And of course the SSB and AM receive sound great to me, too. using the
appropriate filter (which Ten Tec let the operator select independent of
mode - go Ten TEC!)
Filters, specs, and everything else aside though, every person's hearing is
a little different, and I'm sure helps account for certain people's
preferences for particular radios.
73 de Mark N8COO
---------- Adam Farson <farson@shaw.ca> writes:
From: Adam Farson <farson@shaw.ca>
To: Ten-Tec Contesting <tentec@contesting.com>
Subject: RE: [TenTec] Receivability
To: <tentec@contesting.com>
Date: Mon, 28 Oct 2002 10:30:11 -0800
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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