[amsat-bb] Re: Should I abandon full doppler correction?

Patrick STODDARD (WD9EWK/VA7EWK) amsat-bb at wd9ewk.net
Mon Jul 25 10:29:36 PDT 2011

Hi Alan!

I wanted to make a couple of points regarding some of your comments
from your earlier post...

> There was an article in the Journal a few issues back on why the various
> manual techniques are only approximations, sometimes surprisingly bad ones.
> I think the author's call was WA4SCA.

Yes, that WA4SCA is a good guy, smart guy.  ;-)

>  So it does get talked about. With an
> accurate clock, and current Keps it is possible to work a full pass and
> scarcely touch the dial.

I think some forget that even with computer control, you *can* touch
the big tuning knob on your receiver to see what may be away from
the center of the 50 to 100 kHz passbands.  If you don't want to
touch your radio(s), then use the software to tune your receiver
around the passband.  Everyone can't work in the few kHz around
the center of the passbands and have multiple simultaneous QSOs.

It has been nice to see more SSB activity on the weekends.  On the
past couple of Saturday mornings, I've heard SSB QSOs on VO-52
from around 145.900 MHz up to almost 145.920 MHz.  Not as busy
as Field Day, but you won't be out there all alone - and still have
room for additional QSOs.  FO-29 and AO-7 (mode B) have also
had more activity on recent passes I've worked.

> My default is for full Doppler correction.  If the other station is using
> it, fine.  We can concentrate on communicating.  If not, I switch off and do
> it the traditional way.

You don't necessarily need a computer to concentrate on
communicating through the linear transponders.  Computers are
very useful, but not mandatory.  I encourage computer control for
those looking to try the SSB birds, especially with software like
SatPC32.  It will take some time to get the software working
properly with your radio(s), so be prepared to work with your
radio/computer combination.  Otherwise, it will take time to get
the hang of working them "old school", without the assistance of
a computer.  It took me 6 to 8 months, including trying different
antennas and radios receiving the downlinks, before settling on
my current SSB satellite station configuration.  Definitely not
"EasySats", like the FM birds are called, but not impossible to



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