-----Original Message-----
From: Vic Rosenthal <rakefet@rakefet.com>
To: Pete Smith <n4zr@contesting.com>; Amps reflector <amps@contesting.com>
To: <amps@contesting.com>
Date: 08 March 2002 16:29
Subject: Re: [Amps] al-1200 question
>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.
I can see this is the case where you have noise sources with a specific
location, but I have a feeling it doesn't apply to general atmospheric noise
that's uniformly distributed.
Steve
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