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Easy sats



An unusual interest in amateur satellites in the San Diego area prompted the
following document.  It was created, no doubt by the excellent effort of the
Naugle's at the AMSAT booth at the Southwestern ARRL Convention, and the
presentations by Keith, kb1sf....



       GET ON THE AMATEUR SATELLITES TODAY!

Most amateurs have the equipment to get on the Russian satellite 
RS15 immediately.

What you need:

    1.  A receiver capable of receiving in the 29 MHz range on cw.

    2.  A transmitter capable of transmitting in the 145 MHz range. 
        either on FM, SSB/cw or both.

    3.  A method of determining when the satellite is going to be 
        in range of your station.

Use what you have for a receive antenna.  Most anything will work 
from a random wire to a beam.  If you have a beam, turn it in the 
direction of the satellite.  It will definitely improve reception 
when the satellite is below 30 degrees elevation.

If you have an all mode transmitter in the two meter band, you can
work both cw and ssb.  If you have an FM only transmitter, make 
some arrangement to key the transmitter in cw.  DO NOT TRANSMIT TO
THE SATELLITE ON FM VOICE!!!  You will incur the wrath of every
operator in the footprint!   Ssb xmit is ok.
 
Again, use whatever antenna you have available.  A beam pointed 
in the general direction of the satellite will require less power 
to access than an omnidirectional antenna.  Use only the power 
needed to access the bird.  Remember, you are listening to your own 
downlink.  If the beacon is on (it is frequently off), do not let
your signal exceed that of the beacon.  25 watts EIRP should be
more than adequate on cw.  TRY WHATEVER YOU HAVE!  QSB is a
possiblity, keep trying.

RS15 frequencies:
                                      start    end  
Downlink:  29.354   29.364   29.374   29.381   29.376  29.384  29.394
  Uplink: 145.858  145.868  145.878  145.880  145.880 145.888 145.898 
                                      start    end  
                   Beacons:  29.352 & 29.399  (intermittent)

Note that the start and end uplink frequencies of 145.880 result in a
start downlink frequency of 29.381 and an end downlink frequency of
29.376.  This is a result of doppler shift, and applies to all amateur
satellite operations.  The frequencies in the table are approximate.
Maintain a frequency in the uplink range, transmit a series of dits, 
and tune your receiver until you hear your signal.  Make a note of
this pairing as it applies to your equipment, and it will be simple
to "find" your signal on subsequent passes.  If you are keying an
FM transmitter, it is simpler for you to call CQ and let the other
station zero beat your signal.  Your ability to "zero beat" another
signal will depend on the frequency setting capability of your 
transceiver.

Many computer programs are available to determine when the satellite
will be in range.  www.amsat.org has descriptions of some that are
available, and some of them are free.  Or use the rs15.zip file at the
site listed below.  It decompresses to rs15.txt, is in ASCII, and 
is readable on most any computer.  It will appear monthly, for a 
month at a time, and be uploaded at the end of the preceeding month.
The beam heading will only be accurate for Southern California, but
it is possible for other users to estimate a heading using the
geographical location of the sub-satellite point.  Feel free to
disseminate this information in any way you think is appropriate.

The files are available:     http://users.aol.com/dguimont

  sat.txt-------the file you are reading
  rs15.zip------decompresses to rs15.txt

Experienced users are requested to critique this information, and
provide range information for your part of the world.

Beginners fire away with your questions.

Questions to wb6llo@amsat.org     73  Dave   Disagree; I learn.

c:\rs15\sat.txt

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