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RE: Auto Doppler on FO-20



Try the Station Program. It can be downloaded from www.amsat.org and
there is a special key for evaluation(does not save settings).

You can turn the big knob and the program reads the frequency and adjusts.
It works with Icom radios, may not with Yaesu's since they implemented
reading frequency from the radio more recently. Don't know about Kenwoods.

I've found each program has it's own peculiarities and none of the 
programs I've tried are perfect. Your mileage may vary.

Duane Naugle
ko6bt@amsat.org

-----Original Message-----
From: Howard Long [mailto:howard@hanlincrest.co.uk]
Sent: Monday, June 19, 2000 12:12 AM
To: amsat-bb@AMSAT.Org
Cc: John Heath
Subject: Re: [amsat-bb] Auto Doppler on FO-20


Hi John.

I use Fodtrack too, but to be honest in that I find it too difficult to use
for doppler correction. It's not that it's difficult to configure and setup.
Maybe I'm old fashioned, but I like to use the great big round tuning knob
on the front of my radio rather than up and down arrow keys to tune my
radio. I also have found it very easy to press the wrong button, and what do
you know? You're offset's completely wrong again. In particular I find it
annoying I keep accidentally pressing the Save option which overwrites your
carefully keyed satellite data.

However, pilot error aside, I did a test with LO19 as a trial instead of
allowing the modem's AFC to perform correction. I found that it wasn't very
accurate at all, with upto date keps too. Perhaps I should try again.

What I'd like is that if I change frequency at the radio, the program is
smart enough to know this and so will carry on performing doppler correction
at the new frequency I just tuned. You can tune with Fodtrack, but you have
to do it all on the PC. If anyone knows of such a program I'd be interested
to hear about it.

However, I think Fodtrack is a great unit for tracking sats using a rotator.

Maybe I should use a different bit of software!

I'd be interested to know just how many of us _really_ use full doppler
compensation regularly.

There's a note in the Satellite Handbook mentioning an interim solution
between manual compensation and the day when everyone's running FDC. It
states that if one (but not all) of the stations in QSO has FDC, all other
stations should follow that station. However, unless that station is
transmitting all the time, I'm not sure how this could be enforced. Also I
would imagine that during the QSO there should be some sort of exchange as
to which station is in charge of FDC.

As a mere mortal, I can see FDC will happen. I think maybe it needs to be
more thoroughly integrated with the radio, though. Certainly a requirement
for my limited cerebral capacity anyway!

73 Howard G6LVB

----- Original Message -----
From: John Heath <100675.3601@compuserve.com>
To: amsat-bb <amsat-bb@AMSAT.Org>
Sent: Sunday, June 18, 2000 11:15 PM
Subject: [amsat-bb] Auto Doppler on FO-20


> Hi Guys,
> Automatic doppler correction software on a P.C. ,  like Fodtrack tunes
your
> radio to  maintain a doppler corrected signal "at the satellite".  If you
> do it "by ear" you are correcting at your end of the link. Fodtrack works
> brilliantly if both QSO partners have it fully implimented.
>
> Graham Ratcliff VK5AGR wrote an excellent paper on the subject for the
> Amsat-UK Colloquium 1998 with a full description and a very simple CAT
> interface. I built a few interfaces and several of regulars on the Amsat
> VHF net had fun trying it out on FO-20 and 29.  I expect that this type of
> auto correction will be just whats wanted when working P3D on the higher
> frequencies.
>
> The article may be archived somewhere on the net.  If anyone knows where
> perhaps they can post it to the bb.
>
> 73 John G7HIA
> ----
> Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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>

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