[amsat-bb] Re: SSB, SatPC32 and Doppler (was Two Questions)

Dee morsesat at optonline.net
Fri Sep 23 08:42:44 PDT 2011

All & Steve,
Very good procedure Steve.  Let us not get hung up on operating
systems.  The last time I recommended SATPC32 to be purchased by
someone to update their system and also donate to AMSAT to help out
our satellite funds for future sats, I was chastised for suggesting
a Windows program instead of Linux or another op system.
I have been the recipient of many phone calls routed from Martha as
one of the people to assist getting SATPC32 to function that I can
actually say I learned a lot from these questions.  Doppler
corrections on my rig (IC-910) can also be corrected by "RIT" on the
rig itself.  I listen for my voice on an unused freq (if available)
and adjust the RIT setting for clarity.  Then I go to someone
calling CQ or finishing a QSO and call them.  Works fine for me.
While at field day, I answered many questions about how tuning goes
for SSB and FM Birds.  At flea markets I have a set up for the birds
with a IC-910 and a SATPC32 controlled G5400 setup with a split
arrow antenna and make as many contacts as time permits-  Most of
the time, I get to sell a program or 2 since they see it's use and
"Promise" to answer questions if they have any when the y buy it.
This is why I am an AMSAT coordinator here in NJ and try to pass on
what I have learned since Late 70's of satellite ops.  Yes, I miss
the HEO sats and enjoyed them while they were around.  Our sights as
satellite user's must be on the future to get an HEO or MEO
satellite in orbit.  If our membership is to grow we have to start
attracting satellite user's to our ranks by adding their support for
our activities. (Advertisement???)
Presently, ARISSat1 is in the forefront.  It is operating fine and
if you haven't heard it yet, listen on 145.950 +-doppler for a good
signal voice announcements and SSTV.  You may find they call this
satellite "radioskaf-B" in the keps list.
Anyway, follow Steve's procedure and you can't lose.  I worked FO-29
Yesterday and there were about 6 people using that bird.
Dee, NB2F

-----Original Message-----
From: amsat-bb-bounces at amsat.org [mailto:amsat-bb-bounces at amsat.org]
On Behalf Of Stephen E. Belter
Sent: Friday, September 23, 2011 7:42 AM
Subject: [amsat-bb] SSB, SatPC32 and Doppler (was Two Questions)

This e-mail is my feeble attempt to provide a helpful response to
how to set-up SatPC32 for Doppler correction when operating SSB.
I'm not an expert, but I just went through this process because I'm
migrating from Nova to SatPC32.

Since I'm out-of-town, I don't have access to my satellite station,
so I'm doing this from memory.  I also deleted your original post,
as I was hopeful that an expert would step forward to help you.

Your station is fine, with the Kenwood TS-2000 (?) and SatPC32.
Your success operating the FM satellites is a good proving ground.

Here is the approach I took:

(1)  Install SatPC32, update the Keplarian elements, and synchronize
the PC clock to a national standard like WWV/NIST.

(2)  Get your radio and SatPC32 communicating, and verify the
operation (including Doppler correction) using the FM satellites
(AO-27, SO-50, and AO-51).

(3)  Wait for a good pass of VO-52, for example 60+ degrees maximum
elevation.  I suggest VO-52 because it is the newest (compared to
AO-7 and FO-29), it is more tolerant of using too much transmit
power, and it has the smallest transponder correction.

(4)  Open the "CAT" window.  You can move the Window so that it
doesn't block access to the main SatPC32 window.  Tune the radio
above the center of the satellite passband to reduce the QRM to
other users.  Make sure you are in SSB mode on the radio ("C-" on

(5)  Using your call and "Test 1-2-3", listen for yourself while you
are transmitting.  You probably won't hear yourself at all, at least
I didn't.  Using the +100 and -100 buttons in the Transmit
Correction part of the CAT window, try to find yourself.  For VO-52,
you should hear yourself within +/- 1500 hertz.  (I think I was
about +800, but that is from memory.)

(6)  Once you hear yourself using the +/-100 buttons, fine tune
using the +/-10 buttons.

(7)  You can improve the tuning of your uplink/downlink using CW
mode ("C+" on SatPC32).  Zero-beat the Kenwood's CW sidetone with
your received signal.

(8)  *Save* the result by using the "Save" button in the CAT window.
When given the choice, save the transmitter correction.

(9)  Verify that things are working by working a few VO-52 QSOs.

(10)  Repeat using FO-29 and AO-7, in that order.  You may need to
search over a wider frequency range (+/-3000 hertz).

(11)  One other important change when moving from FM to SSB.  Your
power output is important!  Learn how to reduce your power and use
the minimum power needed to hear yourself on the satellite.  If you
use too much power, you'll trash other conversations on the
satellite and your transmissions will be badly distorted!

Good luck!

73, Steve N9IP

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