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Re: Newbie Question: How do I know I am hearing the noise floor of the transponder?

At 04:44 PM 5/28/03 -0400, Bill Acito W1PA wrote:
>Lots and lots of discussions about making sure RX systems are optimized
>on AO-40. How do I know I am hearing the noise floor of the transponder?


Its easy.  

First optimize your pointing onto the satellite and listen to a blank
frequency (no signals present).  
Note the noise level on your s-meter.  
Now off-point your 2.4 GHz antenna from the satellite (but still looking up
into the sky).  
Note the s-meter reading now.  

Did the s-meter reading drop at all (might be very slight).  If not then
you are not seeing the noise floor.  Hearing/seeing the AO-40 transponder
noise floor means that the noise level of the transponder sets the limit of
how weak a signal you hear on AO-40.  If you cannot hear the noise floor
come up when you point onto the satellite then there is more improvement

73, Ed - AL7EB

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