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

Question, FM on AO-40



I don't want to start a argument or propose changing operating practices,
but why is FM forbidden on AO-40? This is a question that I have been
pondering for some time and would like other opinions.

With the passband limited to SSB or CW I understand that the average power
usage is considerable lower then a mode that has a carrier such as AM or FM.
I find it hard to believe that the average power level of FM would be any
higher than the digital modes being used presently. RTTY and PSK31 have a
constant carrier and SSTV has close to half of the bandwidth of FM.
I understand that the bandwidth consumed by FM is much larger then the other
modes but band congestion is not generally a problem with the satellite.

Given that the wider signal does not interfere with another QSO I see very
little difference in power between FM and SSTV, and there is a lot of SSTV
activity on AO-40. If I am putting 100 Watts ERP in SSTV or FM the satellite
should not be able to tell the difference. I understand that the Signal to
Noise will be higher at receive because of the wider bandwidth but that is
not the point.

Just some thoughts to ponder.

Gary Gonnella W6RYO
http://www.w6ryo.com


----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home