[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

re: Have I seen the light? or Revelations of a FNG.



    Have I missed something that is painfully obious here? Are only DAYLIGHT
    passes usable for communications? In other words if I am in darkness are
    the satellites too, and therefore without power? That would explain not
    hearing them at all now wouldn't it. I have mostly tried at night!

Only AO-27 has the restriction, as best as i know.  It is piggy-backed
onto a commercial satellite and has a power budget that only allows for
operation during the first part of sunlit passes, over the middle of the
Northern hemisphere (irrespective of longitude). It has a sun-synchronous
polar orbit, so you'll find it active for 10-15 minutes at a time between
approximate 09:00 and 12:00 local standard time (or 10:00 and 13:00 local
daylight time).  AO-27 is a QRP satellite, and operates like any good QRP
rig does; not much power going out, but it has excellent ears.  You won't
generally hear with a stock rubber duck [nor on a gain omni - the vertical
pattern is wrong), and most people use dual-band yagi (or equivalent).  I
get about 6dBi on the uplink and a theoretical 10dBi on the downlink, and
that's reliable for me down to about 10 degrees MEL in the presence of
urban clutter (and better in rural areas, or other places where i've got a
wide horizon without high power transmitters on ridge tops).  I've worked
it with a long rubber duck (with a chain link fence for a reflector) where
there isn't too much urban QRM, but that's considerated an advanced mode
of operating AO-27.

The most important thing to know about AO-27 is that you need at least to
be able to partial copy callsigns before transmitting, so you don't cause
inadvertent QRM.  Over North America, there's almost always somene on, and
so there is no need to call CQ, just briefly give your callsign and grid
square (or state).  

By the way, especially on weekends, anyone calling CQ generally can't hear
AO-27, so please don't try to answer a CQ unless no one with a decent signal
has tried yet.  Otherwise, you're just causing the additional QRM.

You should be able to hear MIR with an HT, but it's currently only available
in packet or SSTV mode with the current crew.

			   73's and good luck!

				-- KD6PAG

P.S.  Paul, send me e-mail when you can hear AO-27 reliably.  I'm looking
for West Virginia from out here in California and operate from multiple
grid squares.
----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home