Date sent: Thu, 16 Mar 2000 04:21:54 -0800
From: Michael Tope <W4EF@pacbell.net>
Subject: RE: [AMPS] Receiver performance
To: "amps@contesting.com" <amps@contesting.com>,
"'G3SEK'" <g3sek@ifwtech.demon.co.uk>,
"'Peter Chadwick'" <Peter_Chadwick@mitel.com>
> e.g. proper gain distribution, then it will work. Unfortunately,
> with the current level of technology available, sound design
> principles seem to dictate that the DSP appear in the audio
> section. Hybrid rigs like the FT1000MP and TS950SDX appear to
> be the way to go.
38 kHz is a lot closer to audio than 9 MHz would be.
The flaw is in our "labels".
The shortfall of DSPs aren't "frequency" problems or "AGC"
problems.
Moving the DSP from 300-3000 Hz to 38.000- 41.300 kHz won't
cure the problems, and neither will moving it into the AGC loop.
The problem is dynamic range, and the fact the DSP is way down
the chain from the mixers. The DSP doesn't have the resolution,
speed, or power to process ahead of the narrow IF filters without
screwing up something else.
Once it is after the narrow filters, it might as well be at audio.
73, Tom W8JI
w8ji@contesting.com
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