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FM Satellite Summary (October)



Here is a one line summary of currently active FM birds that you can
receive on your Mobile or HT FM rig and mobile vertical whip antenna.  

 1) SUNSAT in Mode B for APRS/UI and PARROT mode for voice to 10 Oct
 2) MYSAT is a new signal on the air, but not enabled for user uplink

SAT   DOWNLNK UPLINK  S MODE               COMMENTS
----  ------- ------- - ------------------ ----------------------------
UO11  145.825         4 R FM Bell202 ASCII Telemetry only
UO14  435.070 145.975 5 J FM Voice rptr    lots of fun every pass
AO27  436.795 145.850 3 J FM Voice rptr    days only but fun
SO35  145.825 436.290 8 B FM Voice rptr    One pass per day after 10 Oct
      145.825 145.825 8 P FM VOICE PARROT  On through 10 Oct
UO22  435.120 145.900 3 J 9600 bd FSK BBS  ON
KO23  435.170 145.900 4 J 9600 bd FSK BBS  OFF&ON unreliably
KO25  436.500 145.980 3 J 9600 bd FSK BBS  ON
TO31  436.925 145.925 5 J 9600 bd FSK DATA ON downlinks images
GO32  435.225         ? J 9600 bd FSK tlm  1 packet every 30 sec
SO35  145.825 436.290 8 B 9600 bd FSK data ON all non voice passes
                          1200 bd AFSK up  on the uplink is 7db better
SO35  435.250 145.825 4 J 9600 bd FSK      ON after 10 Oct?
              145.900 4 J 1200 bd AFSK up  ON after 10 Oct?
MYSAT 437.325 TBD     ? J 9600 bd FSK data ON

* If you dont hear it, then DONT TRANSMIT!  Check your gear...

Between the hours of about 6 AM to noon and 6 PM to midnight local SUN
time there is usually one of these birds in view for a few minutes to keep
you entertained while traveling.  UHF requires +/- 5 or 10 KHz Doppler
tuning.  The "S" column is a subjective signal strength assessment.  A
20" vertical whip in the center of your car roof  will give you success as
shown below.  This acts as a 3/4 wave on UHF giving almost 8 dBi above 
30 degrees over a good groundplane for the UHF downlink birds (for the
cener 1/3rd of the pass).  For  SUNSAT which operates mode B with a
stronger 2m downlink and your 50 watt mobile uplink, a normal dual-band
mobile antenna will do better closer to the horizon.
                                                SIG RECEIVE RANGE
USING THE 20" WHIP FOR MODE J PACSATS:          --- ------------------
As a rough approximation consider this table     9  Horizon to Horizon
which  I have subjectively  determined after     8  5  deg and above
3 months  of daily monitoring. Home stations     7  10 deg and above
with 50' of RG 8  should subtract abt 3 from     6  15 deg and above
the signals and 5/8  or dual band, or "gain"     5  20 deg and above
antennas  should also subtract about 2.          4  25 deg and above
                                                 3  30 deg and above
The PACSATs  do not  officially digipeat  UI     2  3 ele beam required
packets,  but  you can still  see status and     1  6 ele beam required
telemetry and the USER lists on your Kenwood
data radios or any radio with 9600 baud TNC.  For more info on mobile
satellite operations see http://web.usna.navy.mil/~bruninga/astars.html

NOTE:  The above assessments of the 20" whip were made with a .8 dB
NF preamp and 150 feet of coax.  OPerating recently mobile with the THD7a
Handheld barefoot with no preamp did show a decrease in the amount of pass
coverage.  This is because the THD7a is optimized for the 440 band in the
USA, not the 435 Band where it is a few dB down there.

Errors, omissions, corrections welcome.  I will re-post this when ever I
hear of changes in status.  For more detail, of course, read the AMSAT
News Service bulletins and AMSAT WEB pages http://www.amsat.org

de WB4APR, Bob


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