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To: tentec@contesting.com, orion@contesting.com
Subject: [TenTec] RE: [Orion] ORION PERFORMANCE
From: Bill Tippett <btippett@alum.mit.edu>
Date: Wed, 03 Nov 2004 18:17:05 -0500
List-post: <mailto:orion@contesting.com>
Eric you accidentally posted this to Ten-Tec instead of
Orion, so I'm copying your post below for benefit of the
Orion reflector.  Your settings are quite similar to mine for
SSB contesting, so I'll just note differences:

a. Agree.

b. Agree. I've even gone to 1600 Hz at times.

c.  Agree.  I also set RIT -100 when doing S&P to
compensate for rapid zero-beating when I typically
undershoot on USB.  LSB would be opposite (+100).
I also set Audio RX EQ -15dB which "processes"
received audio to have enhanced highs (like a Heil
HC-4 in receive).

d.  Mostly agree.  Threshold for my 10m stack is typically
4uV or higher.  On the low bands, Threshold would be MUCH
higher.  I set Decay a bit lower (30 uV) and vary Hang
depending on conditions, typically 0.30 (default) to 0.04.

e.  Agree except I've found the HW NB improves S/N
noticeably when the band is almost dead (early AM
and late PM).  Of course it should never be used when
there are strong signals present (which is never the
case at the times I mentioned).

f.  Agree.  AN is sometimes useful for CB carriers or
intentional QRM on 10, but I would turn it off as soon
as possible.

        I'm amazed how similar our SSB setups are
for contesting!

73, Bill W4ZV

>Well, I'm going to stick my neck out on the reflector and describe what I have been using for SSB contests. Probably some other
people can point out how my settings can be improved.

a) In the "Filters" menu, turn off auto-select and force the use of the 1.8 kHz filter. (Don't forget to revert back to auto for
CW - hi!)

b) Set bandwidth to ~2000 Hz, according to degree of band crowding and your taste. I've run the bandwidth all the way down to 1700
Hz in horrible crowding. On a less congested band like 10m, I'll open it up to 2100 or 2200.

c) Set passband tuning +150-200 Hz. This shift compensates for the narrow filter choice to improve intelligibility.

d) AGC: use "prog" setting with parameters like these:
AGC Hang: I tend to keep this short, <0.20 seconds, in a contest on a crowded band, where I want to be able to at least hear
the presence of a weak caller in the gaps between loud signals overlapping my listening frequency. 0.12 seems OK, and I've even
used 0.00. This is certainly not a good setting for conversational QSOs.
AGC Decay: I run pretty fast decay, again to allow the AGC to drop down quickly to catch a weak stations. ~50 dB/s seems OK.
This is definitely NOT a conversational setting!
AGC threshhold: I start with this value at its maximum (191.48 microvolt), and reduce it until I start to hear band noise just
come up on an empty frequency. Tune outside of the band if no empty frequency can be found. On a very crowded band like 40m, I
will use an even larger setting. There is no value, and some harm, in setting this parameter too low on a band full of loud
signals. Set it just low enough to reliably copy the weakest signal detectable among the QRM or QRN. This value is the most
variable -- it depends on conditions, local noise, and your antenna in use on the band.

e) NR and NB: off unless absolutely necessary. Why do more processing on the signal than one needs?

f) AN: I leave this off unless I encounter a situation where a notch filter is needed. Same idea: do the least amount of
processing on the signal for the conditions.

I'm looking forward to hearing others weigh in...

   -- Eric K3NA

-----Original Message-----
From: Eric Rosenberg [mailto:wd3q at starpower.net]
Sent: 2004 November 3 15:54
To: <http://lists.contesting.com/mailman/listinfo/tentec>eric at k3na.org

Eric --

Can you be more specific about your changes?

As I said in my email, I lose track of my expectations... and then get
messed up trying to figure out if the radio sounds as good as it should!
 Parameters like NR (which was great on the Omni-6+) just didn't seem
right to me;  I haven't gotten the hang of the AGC, nor do I really
understand the HW NB and the H vs L in re: PBT.

I suspect I'll eventually get there...

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