[amsat-bb] Re: SO50

M0ZLB m0zlb at btinternet.com
Tue Sep 19 08:20:30 PDT 2006

Thanks Alan,

Bit of a "performance" reconfiguring for the switch on tone and then
switching back for the shortish pass! Guess that's why it seems unused over
here, no-one can be bothered!

I'll have a try on the next pass!


-----Original Message-----
From: Alan P. Biddle [mailto:APBIDDLE at MAILAPS.ORG] 
Sent: Tuesday, September 19, 2006 4:16 PM
To: 'M0ZLB'; 'Amsat BB'
Subject: RE: [amsat-bb] SO50


It is a DIY process these days:


Weekly Satellite Report

To switch the transmitter on, you need to send a CTCSS tone of 74.4 Hz. The
order of operation is thus: (allow for Doppler as necessary)

1) Transmit on 145.850 MHz with a tone of 74.4 Hz to arm the 10 minute timer
on board the spacecraft.
2) Now transmit on 145.850 MHz (FM Voice) using 67.0 Hz to PT the repeater
on and off within the 10 Minute window.
3) Sending the 74.4 tone again within the 10 minute window will reset the 10
minute timer.


Note that there is a brief but noticeable delay between keying your
transmitter, and the satellite transmitter coming up.  A quick "kerchunk"
will not work to see if it is up.  Use a couple of seconds with 74.4 Hz to
arm the bird, and then switch to the other PL.  From there, you can tell
when it comes up.


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