[amsat-bb] SO-67 Recordings 29Nov2009 USA

John Papay john at papays.com
Mon Nov 30 12:10:57 PST 2009

I have uploaded the three morning passes of SO-67 as follows:




If you want to make successful qso's on SO-67, you
must change the way you normally operate.  The three
second tail is different than any other satellite so
you must adjust for it.  If you don't, you will not
have much fun.

The first way to make a good contact is to wait 3 seconds
after the last station transmits before you transmit.  You
will then be able to transmit for as long as the qrm will
allow.  I believe there is a 30 second timer which will
come into play if a valid signal with PL is continuous
for that period of time.

If someone calls you and you can reply in less than three
seconds, by all means jump right in and transmit as soon
as the other station drops.  There is enough time to
acknowledge with your grid square and a "qsl."  There is
normally not enough time to add your callsign. If you have to
say more than 3 seconds worth, wait until the tail timer
expires (3 seconds) before you start transmitting.

If you are full duplex, you can easily transmit on the
3 second tail, hear yourself drop, unkey and then begin
transmitting again.  That has worked for some.

There is a third way to get around the tail timer and that
is to start transmitting before the station you are working
unkeys.  If there is a squelch crash, you missed and the tail
timer will get you.  If you get your transmitter on before
the other station drops, you'll be able to exchange your info
without dropping.  It's tricky and full duplex helps.

There are many other factors which can contribute to a drop
including being clobbered by another station.  If the
clobbering station is not running PL, the three second timer
starts and the bird will drop.  Again, full duplex helps to
hear what is going on when you are transmitting.  Running
too much deviation can also mute the receiver and start the
timer.  Turn your mic gain down and your processor off.  Use
narrow FM on your transmit signal if your radio has it.

Incorporating a 3 second waiting period is very difficult because
we have been programmed to respond immediately after the station
we are working stops transmitting.  Failure to begin transmitting
immediately usually results in someone else making a call.  However,
when working SO-67, transmitting immediately will start the 3 second
timer.  It takes discipline to wait.

The last option is to just listen and let the others experience the
fun.  (smile)

John K8YSE

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