[amsat-bb] RAFT Packet Operator assistance Desparately needed

Robert Bruninga bruninga at usna.edu
Tue May 15 15:14:38 PDT 2007


We desperately need some AMSAT OSCAR class stations in the
Central USA to complete the RAFT radar fence test ASAP. 

Deorbit is in the next two weeks, much earlier than previous
predictions, and so we will not get another comfortable evening
pass window.  Prime passes now are occurring around 4 AM and
moving earlier (sorry).  Before, we asked for Southern USA.  Now
we realize that someone in most central states have command
potential.  Anyone within about 1000 miles E/W of North Texas or
600 miles north and south are ideal!

Station requirements:
1) OSCAR class tracking 2m beam for up/downlink 145.825
2) Standard AX.25 1200 baud packet
3) Simple HYPERTERM text commanding
4) Familiarity with TNC's and TNC commanding
5) Prepared to record 1 minute of audio heard on downlink

Unfortunately I am going to Dayton this weekend, but we have to
really be ready for this next week and get this test done.  None
of the principals involved in this design can do it because we
all live too far away from the 216.98 MHz RADAR fence
transmitter in North Texas.

See WEB:  http://www.ew.usna.edu/~bruninga/ande-raft-ops.html

Thanks, WB4APR, Bob

-----Original Message-----
Sent: Tuesday, April 24, 2007 1:23 PM
Subject: RE: [amsat-bb] RAFT Packet Operator assistance needed

We only have 7 days left in this operating period and really do
need a good OSCAR station in the Southern USA in a line from AZ
to GA to conduct this test of RAFT flying through the 80
megawatt radar transmitter beam originated in north Texas.

There is only one viable pass per day per command station
location in the early evening....  The trick is to command the
satellite to turn on its downlink carrier and Radar receiver
exactly 30 seconds prior to passing
through the fence and then having an audio recorder running to
"hear" (record) the tone when we pass through the radar beam.

Commands are a simple CONNECT XXXX at the cmd: propt, then an
exchange of passwords, and then sending a simple typed command
at the right time.

RAFT can he HEARD just fine on ALL FIVE passes leading up to
this last pass per day, so you can test your RECEIVE capability
on any pass, but can only command in the dark (due to
overcharging on batteries makes uplink receier deaf)...

If anyone can conduct this test please let us know.  Only one
person per pass can attempt this, so we want the best gun at the
stick.  Fully conversent at the TNC "cmd:" prompt and preerably
with experimence with the KPC3+ remote-sysop command mode.

Bob, WB4APR
USNA Satelite Lab


> ----- Original Message ----- 
> Sent: Monday, April 23, 2007 12:32 PM
> Subject: [amsat-bb] RAFT Packet Operator assistance needed
> 
> > We need AMSAT operator help with the RAFT satellite 
> > Test.  We need somone with a 2m beam and familiarity 
> > with packet that lives in the Southern USA from 
> > Arizona to Georgia (AZ, NM, TX, OK, MS, ALA, GA).
> >
> > RAFT is past its mission life time half-way point, 
> > and we have not been able to find anyone in the above 
> > footprint to help us conduct the primary mission which 
> > was for the satellite to detect its own passing through 
> > the DOD's radar fence.  When it flies through the 
> > North American Space-Object fan beam, we should hear 
> > about 1 second tone that anyone can hear on the downlink.
> >
> > Due to its low orbit and small footprint, turning on 
> > the Radar Transponder can only be done in the shared 
> > footprint between the radar transmitter in North Texas 
> > and the command station.  The ideal command station has
> > these atributes:
> >
> > 1) Lives in AZ, NM, TX, OK, AK, LA, MS, AL, GA, W.FLA
> > 2) A reasonable 2m beam for ops on 145.825
> > 3) A packet TNC
> > 4) Familiar with dumb-terminal TNC operations such as
> >   A. Connections, Converse, UNPROTO, etc
> >   B. Remote sysop logon to a Kantronics TNC
> >
> > The objective of these southern command stations is to
> > logon, send the command to activate the RAFT Radar 
> > receiver for 1 minute in anticipation of passing 
> > through the fence.  Then hopefully recording any audio 
> > heard on the downlink (145.825).  Of course, once the 
> > radar receiver is on, everyone in the footprint should 
> > be able to hear it.
> >
> > For info, see the ANDE-RAFT operations page:
> > http://eng.usna.navy.mil/~bruninga/ande-raft-ops.html
> >
> > Several AMSAT hams built this tiny Radar receiver as a
> > possible common device for all future HAMsats, and we 
> > would like to get feedback on its performance.  But 
> > they all live up North.  If you have a beam and 
> > familiarity with TNC's please let us know.
> >
> > Bob, WB4APR.
> > US Naval Academy Satellite Lab



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