[amsat-bb] RAFT Fence Doppler Plot Posted

[Robert Bruninga]

RAFT-REENTRY CAMPAING web page now has a Doppler Plot against
TIME:
http://www.ew.usna.edu/~bruninga/craft/save-raft.html

To our surprise, the RAFT XP-217 radar receiver hears the Radar
sidelobes as long as it is above the horizon!  I guess that
makes sense for a 700 KW transmitter.  Even if we are not in the
80 Meggawatt main beam, the radar receiver does still hear it
(even though its RX sensitivity was intentially only designed to
be only  - 40 dBm? or so)...

Now, is there anyone on the AMSAT-BB that would like to analyze
this portion of the Doppler Plot and prove the timing.  The only
thing I'd like to confirm is the added inflection point at the
start (probably due to the bistatic radar situation) which makes
this different than the usual "S" plot with only a 3rd order
curve.

Bob
WB4APR


> -----Original Message-----
> From: Robert Bruninga [mailto:bruninga at usna.edu] 
> Sent: Monday, May 28, 2007 12:26 AM
> To: bruninga at usna.edu; rx217 at alum.WPI.EDU; 'Matt Bennett'
> Cc: 'Lauret & Henk'; 'Ron Hashiro'; 'Dieter Schliemann'; 
> mail at mike-rupprecht.de; iana at kcbbs.gen.nz; 
> k.swaggart at charter.net; jf1aje at aprs.xii.jp; 
> veillet at cfht.hawaii.edu; tanimoto at hawaii.rr.com; 
> ah6gr at arrl.net; dquagliana at aol.com; hhm_74115 at cox.net; 
> walterh at k5wh.net; crabtrej at erau.edu; wa6lie at msn.com; 
> ea4ekh at telefonica.net; zl2cia at amsat.org; 
> geoff.clark at clear.net.nz; matsu at aje.jpn.org;
ei7m-wkt at asahi-net.or.jp
> Subject: RAFT Voice may notebe fully set?
> 
> I blew my pass.
> 
> It arrived about on schedule (Keps dated 27th at 1313z.)
> At first I got no response to my LOGGON attempt.  SO I assumed
> that the southern stations attempts had locked me out.  So I
> forced a  disconnect so that I could reconnect to RAFT and at
> least check out the voice.
> 
> That was successful, but then I saw the  earlier password
> challenge coming back.  At this time I was no longer connected
> and didn't have time to re-sequencce everyting.
> 
> SO my commaindng was a failure due to cockpit error.
> 
> BUT when I CONNECTed RAFT, the VOICE came up just fine, but
did
> NOT speak any packets sent to it.  So I wonder if all settings
> are correct.  Maybe the European or other command stations not
> in the footprint of the Southern USA FENCE could logon and SET
> these settings:
> 
> MYAPRS TALK
> MXMIT ON
> 
> It is clear that the others ARE set OK, since CONNECTing RAFT
> does bring up the voice transponder.  SO these are OK and do
not
> need to be confirmed.
> 
> CTR A OFF
> CONOK ON
> CMSG OFF 
> 
> But if MYAPRS TALK is not set or if MXMIT ON is not on, then
the
> voice module will not speak APRS messages...
> 
> Bob, WB4APR
> 
>