[Amps] al-1200 question

Vic Rosenthal rakefet@rakefet.com
Fri, 08 Mar 2002 08:03:44 -0800


Pete Smith wrote:
> 
> > Improving your antenna by 3 dB, whether by improving the
> >gain or reducing loss, nets you 3 dB on transmit AND RECEIVE !
> >
 
> Well, yes, but in most cases at HF the added receiving gain is not really
> useful, because your ability to hear is limited by signal-to-noise ratio,
> not path loss, and the extra gain will just bring up the ambient noise by
> the same amount as the desired signal.

But if you increase antenna gain you are increasing signal strength just because
you are narrowing the beamwidth (in the horizontal or vertical plane, or both). 
Since the desired signal comes from one direction and noise is more or less
evenly distributed, a directive antenna does improve the signal/noise ratio.

73,
Vic, K2VCO
Fresno CA