[amsat-bb] Re: Receiving RAFT on 216.98 MHz ?

Robert Bruninga bruninga at usna.edu
Thu Dec 7 14:39:10 PST 2006

> that none of my receivers will receive at or
> near 216.980 MHz.
> What were other amateurs planning to use to
> receive the pings from RAFT on 216.98? Is

You don't need a receiver.  Just listen on 145.825 RAFT downlink
and you will hear the Radar ping on RAFT's downlink.  RAFT has a
216.98 MHz direct conversion receiver and so it will hear a tone
proportional to the Doppler as it flies through the radar fence.
This should last about a second.

And it is not really a ping.  It is an 80 meggawatt CW
transmitter that is on all the time.  When we fly through it,
you will simply hear a tone for a second or so.  The pitch of
the tone will be constant, but its actual frequency will depend
on the angle that our spacecraft path makes with the
intersectino with the beam.

A SECOND experiment for those inclined is to listen on 216.98
MHz and see if you can hear our 4 milliwatt 216.98 oscillator.
A lot of work and not much gained.  Of course if you do have an
SSB receiver that can listen to 216.98, you can be entertained
by any of the other 10,000 pieces of space material that also
flies through the fence.  If you live in the Southern states, a
simple dipole receiver will hear severl things a day.
Particularly listen during meteor showers and it is like rain on
a tin roof... (that is an exaggeration, but compared to one ping
a day from ISS, it makes the point)...

Read about the fence on the RAFT web page:


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