TenTec
[Top] [All Lists]

[TenTec] S-meter and RF Gain

To: tentec@contesting.com
Subject: [TenTec] S-meter and RF Gain
From: Bill Tippett <btippett@alum.mit.edu>
Reply-to: Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Thu, 09 Feb 2006 15:50:36 -0500
List-post: <mailto:tentec@contesting.com>

NQ5T:

 >There are plusses and minuses on both sides of the argument.  The reason it
does this is because T-T bowed to much user complaining and/or confusion
about Threshold, and somewhere along the line (don't recall which release)
tied Threshold and RF Gain together.  Unless I'm mistaken, it is the fact
that reducing RF gain now also increases Threshold that's causing the
S-meter to rise.  So in a sense, we have ourselves to blame ... :-)

         You've got it slightly scrambled Grant.

1.  1.372 linked RF Gain and AGC Threshold...a major improvement IMHO.
2.  AGC Threshold **never** had any effect on the S-meter.
3.  AGC Threshold could **only** be set by listening to band noise.

 >I was used to runing with Threshold set at band-noise peaks, anyway.

         True, but it was cumbersome until 1.372 to go into
and out of Menu>RX every time you changed bands or an antenna.
After 1.372 there is no need to go into Menus, but it still
requires carefully listening to band noise.  The traditional
visual indication is much faster IMHO.

         Here are Sinisa's March 2004 comments:

"Orion's RF GAIN does not control the AGC threshold directly. Orion 
users have to activate menus
and then select and change the clumsy AGC THRESHOLD setting (which 
does not move the S meter),
instead of simply turning a knob counter-clockwise as on "less 
modern" receivers. Therefore, speaking
ergonomically, Orion's AGC THRESHOLD control is less adequate for the 
purpose due to:
* lack of correlation between AGC THRESHOLD values and S meter noise readings;
* lack of dedicated knob.
Both disadvantages can be overcome, but the price in time and effort 
may simply be too high in contests.
Particularly cumbersome is to know "how much of it" to apply, 
compared to RF GAIN method
where one simply looks for a non-moving S meter."

http://www.geocities.com/va3ttn/UsingOrionRX.pdf

         1.372 solved most of these issues with
the exception of the last sentence above.  Linking
RF Gain to the S-Meter now solves that one.  Back
to the past!

                                 73,  Bill  W4ZV


_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec

<Prev in Thread] Current Thread [Next in Thread>