----- Original Message ----- From: "Andre" <[email protected]> To: <[email protected]> Sent: Saturday, January 21, 2012 8:12 PM Subject: [amsat-bb] Re: Thanks for all the ...
> Good point, a preamp is to cancel out the cable losses, anymore and you > are just boosting the background noise and not improving the reception. > So if your cable is very short there is not point in using a preamp. > > 73 Andre PE1RDW Hi Andre, PE1RDW It depends on the noise figure NF of your receiver. Lets suppose the NF of your commercial receiver is as usually in the order of 6 dB, then a preamplifier with a NF = 0.5 dB and 15 to 20 dB gain will improuve your (S+N)/N ratio even if the lenght of your coax cable between the antenna and receiver is very short. 73" de i8CVS Domenico _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
