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Re: A question about 75 Ohm connectors



Hi Jon, All,

The problem for the guys running the AIDC 3731/3733 is usually getting
enough attentuation into their rx line after the downconvertor.  For
instance, I use about 50 feet of cheap rg-59 on mine and still have to put
about 12 db of attenuaters inline just to get the noise down to an
acceptable level.

I have my cold sky noise level set to just under S1 on the meter, the AO-40
transponder noise floor comes up to about 5-6 db at any squint below 25, and
the beacon level here is about 30 db above cold sky. That's on a 34" solid
dish with circular patch feed.

There's really no point being too fussy about the downconverted 144 mhz
signal. All you need is enough to get some noise on the rx, unless you
actually like listening to S5-7 noise all the time. Of course, if you do,
the bright side is that all your satellite signals will be S9++, hi...

regards,

Roy VE7BPB
Vancouver




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