Old TenTec's don't use post-AGC audio filters. They use pre-AGC audio
filters. It's hard to tell the difference between their af filter and an
IF filter. It's sorta like these new DSP radios with their AGC developed
after the IF chain or at least some resemblance.
N4LQ
-----Original Message-----
From: Adam Farson <farson@shaw.ca>
To: Ten-Tec Contesting <tentec@contesting.com>
To: <tentec@contesting.com>
Date: Mon, 28 Oct 2002 10:30:11 -0800
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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