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Expanding AO-27 use [was: AO-27 Internet Monitor Gateways]



Without commenting on the proposal in general, i have serious reservations
about such operations on weekends over North America.  During such times,
AO-27 is often seriously overloaded and difficult even for experienced
operators to use.  People are unavoidably stepping all over each other,
and picking out callsigns is difficult enough as it is.  As a regular
operator on AO-27, i've heard numerous cases where i've heard station A
calling station B, and station B clearly should hear station A.  They both
have good signals into the bird. But station B is unable to answer simply
due to congestion.  I think adding comparatively loud, encoded data at the
end of transmission means fewer contacts can be made and more tranmissions
will have repeated.  Repeating means two additional transmissions, one
requesting retransmission and a second to attempt to reply.

Under current conditions on transcontinental passes, no one expects to have
what an HF operator would consider a full exchange.  We generally do just
enough to know we have actually made contact and there simply isn't time
or bandwidth for such formalisms.  Indeed, the only operator i've heard who
routinely does full exchanges is XE2YVW.  He's far enough south that the
bird is less congested, and the rest of us so much appreciate his roving
activities that space is left to complete such exchanges.  He is also very
courteous and always does QSOs in order, so people respect that.  Almost
everyone else is brief and informal for the purposes of conserving trans-
porder time.

So, at least until Septmber, when we hope to see two (or more) J-FM birds
launched, weekend FM transponder time is extremely tight much of the time.
Adding tones at the end means that fewer people will be able to complete
contacts and there will be more retransmissions.  As it is, many operators 
will not work AO-27 on weekends (if at all), due to this congestion. 

So, whether or not putting additional or piggy-backed traffic to AO-27 is 
appropriate on weekdays, or over other areas, i sincerely hope that such 
operations are not recommended on weekend passes over North America at 
this time.
                        Respectfully submitted,

                           -- KD6PAG  


P.S.  I think it's far more important to develop affordable means of
operating at 38.4 Kbps, now that we have two operational satellites with
that capability.  This should be considered both for space and terrestrial 
use, and having good test signals readily available, potentially several
times a day worldwide, should help speed development efforts.  Although
technically more difficult to receive, 1 Mbps downlink is also now in
operation on our most recently launched amateur satellite and could be 
the basis for more advanced terrestrial experimentation as well.
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