Re: [amsat-bb] Geosynchronous Satellites

[Phil Karn <karn@xxxxxxxx>]

>3.) FM is not efficient as a mode in terms of propagation.  FM is inherently
>more wide band than SSB or CW.  You may transmit 25 watts on SSB and 25
>watts on FM but the SSB signal will get you farther.  CW will be even
>better.  This is because as you increase the bandwidth your power is spread
>out over a wide range of frequencies.  Hence your power density decreases.
>This is the reason why weak signal and EME types use SSB/CW and not FM.

Gee, then I wonder why all the analog C and Ku-band TV satellites use
FM rather than AM.

>orders of magnitude.  Considering that the RF field falls of inversely
>proportionally to the distance between two objects, it follows then that two

Last time I checked, it ws inversely proportional to the SQUARE
of the distance.

Phil
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