Grant, you are absolutely correct. What I was addressing was the fact that the
S meter readings aren't especially accurate on any of today's receivers,
including the Orion. I've re read my post and I can see that I did not make
that point clear.
Thanks for your insight.
Mike NM7X
Date: Fri, 23 Dec 2005 21:25:27 -0500
From: "Grant Youngman" <nq5t@comcast.net>
Subject: Re: [TenTec] Orion with V2 rf gain
To: "'Discussion of Ten-Tec Equipment'" <tentec@contesting.com>
Message-ID: <20051224022538.40052319ADC@dayton.akorn.net>
Content-Type: text/plain; charset="us-ascii"
> With today's technology, it's not necessary to use this
> indirect method.
> Let's bury this dinosaur once and for all.
>
Not so fast.
The point of the S-Meter movement upward, as I recall the endless
discussions of all of this regarding the Orion, is to give you a notion of
the MINIMUM signal that will impact AGC, via the THRESHOLD setting. If you
leave the S-meter reading unaffected, what does it tell you ... Not much.
This "artifact of a bygone era" is telling you what signal level is required
to affect AGC. For example, if you have an s-7 average noise level, one
might, to keep things a bit quieter, increase THRESHOLD until the meter read
about s-7. At least that was the point as I recall it, and I've always found
it useful for that purpose. And why not? You are unlikely to hear any rare
DX below this level, anyway. And it sure keeps the nosie level down,
without any reduction in RF (IF) gain.
The coupling of RF GAIN and THRESHOLD in one control in later Orion firmware
releases was done to satisfy a lot of people who couldn't get their brain
straight about THRESHOLD (the level at which AGC action would begin, RF GAIN
(really an IF gain control), and the fact that there were two separate
controls with quite different functions.
So T-T simplified things a bit by providing some THRESHOLD shift as RF gain
is adjusted. But you can still set threshold as you like, since the control
is still there. Perhaps, once again, some refresher on why this is set up
to do what it does would be in order :-)
Grant/NQ5T
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