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Re: FM Satellites

bruninga@nadn.navy.mil writes:

> 4)  In my opinion, the FM satellties cannot possibly support TWO-WAY
>  exchanges between every possible combination of users.  If there are 60
>  stations, then it would take 60*60*2, or 7,200 transmissions!  But if the
>  objective was just to "join the group" on that pass, then each of the
>  60 stations could say a full 5 seconds of information to EVERYONE and all
>  60 stations would be successful in only 5 minutes of the pass!

No argument with your point, but I believe this is a binomial combination, 
where the following applies:

    n! / r!(n-r)!
  where n=60 and r=2

Hence, only 1770 "combinations" are available.  

At 5 seconds for each transmission and each exchange requiring 2 
transmissions, a perfect 15 minute pass could "only" handle 90 full 
exchanges.  But why quibble over the small stuff ? <grin>

Jerry, K5OE
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