NOT TRUE!
The received signal is a coherent source, while ambient noise is incoherent
(random in phase), so you will definitely se an increase in signal to noise
ratio. This is unlike adding a preamplifier which WILL amplify the noise
and signal coming into the antenna.
----- Original Message -----
From: "Pete Smith" <n4zr@contesting.com>
To: <amps@contesting.com>
Sent: Friday, March 08, 2002 7:37 AM
Subject: Re: [Amps] al-1200 question
At 07:14 AM 3/8/02 -0500, wd8jja wrote:
>Here is something to ponder. Doubling your transmit power nets you 3 dB
>gain on transmit. 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.
73, Pete N4ZR
Check out the World HF
Contest Station Database at
www.pvrc.org
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