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Re: super capacitors (fwd)



>using a patch would be nice, but in reality a nice dish  with a narrow 
>beamwidth will keep the unwanted sewer rats out of your  receiver. 

Not really.  At home, my PC shows 4 wireless LANS so strong
inside my house from neighbors.  At work, there are dozens.
It is impossible to use 2.4 GHz band even with high gain very
narrow dishes, because the RF lans are coming in from everywhere.

And although the dish may have 40 dB of gain at S band, the
difference between a 0.01W wireless LAN only 100 meters 
away is still 36 dB stronger than a 1W amateur satellite that is 
40,000 km away.  The difference between these two signals 
is 66 dB.  So I think the 2.4 GHz band is practically useless
for receving weak signals on amateur radio anywhere in an
urban environment.  Certianly is here.

We used to use our AO-40 receive system on a 4' dish to
demonstrate SUN noise and quiet sky to studnets.  It could even see
a noise rise when pointed at a building (300k).  That lab
is now useless, since the entire S band is overloaded with
QRM from wireless LAN's.

Just a data point...
de Wb4APR, Bob
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