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Re: so35



On Tue, 6 Jul 1999, KF4FDJ (Mike in Ft. Myers, FL) wrote:

> I'm not arguing either Bob, but trying to quell big station bashing
> ... I still take issue with your basic premise....

Sorry, in context I was only talking about the dozen or so FM or digital
"contention" based uplinks.  My fault if I did not make that clear.
 
> ... However, most stations with marginal downlink antennas HAVE to run
> more power than would be necessary if they could hear well, just to be
> able to hear their own signal.

THis does not apply on an FM bird or any of the PACSATS or MIR or SAREX.

> It is apparent your APRS mindset is at work here.  

Yes. Guilty.  I was only talking about the FM and digital birds.

> You state that the polarization mismatch penalty is 3 db.  Only if you
> are using a linear antenna.  If you have a RHCP antenna receiving a LHCP
> signal, in theory the penalty is infinite.  In reality, the penalty is
> somewhere around 20 db....
> Or do it the efficient way and throw in switchable sense. 

We agree.  I assumed stations would operate effeciently and therefore
would not see any more than 3 dB loss.

> Just because a person has assembled a top notch station does not
> relegate them to ranks of villainy. 

I think you are miss representing my comments about the 5 watt nominal
uplink power on an FM or digital bird to some other Email bashing from
other authors.  I did not mean to bash anyone.

I appologize again to the analog users.  THose guys can hear their own
downlink and can and DO adjust their power as needed.  I was only talking
about the majority of current satellites that are either FM or use digital
contention channels.  On these birds, the downlink conveys *no*
information about uplink power.  And in most cases 5 watts should be
sufficient (if everyone else did the same).  Sorry I did not make that
clear enough.

bob


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