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FM Satellite Summary (October)
- Subject: [amsat-bb] FM Satellite Summary (October)
- From: Bob Bruninga <bruninga@xxxxxxxxxxxxx>
- Date: Mon, 9 Oct 2000 12:14:31 -0400 (EDT)
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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