By definition, from psychophysics, 1dB is the increase or decrease in signal
strength that can be discerned by an average observer on 50% of occasions.
A 2dB increase should be discernible by an average observer at any signal
level.
cheers
end
Barry Kirkwood PhD ZL1DD
Signal Hill Homestay
66 Cory Road
Palm Beach
Waiheke Island 1240
NEW ZEALAND
www.waiheke.co.nz/signal.htm
----- Original Message -----
From: Colin Lamb <k7fm@teleport.com>
To: 2 <2@vc.net>; AMPS <amps@contesting.com>; at towertalk
<towertalk@contesting.com>
Sent: Friday, 07 September, 2001 7:19 AM
Subject: Re: [AMPS] True Or Not True #2
>
> Rich asked "On HF/MF skywave, is a 58% increase in power out (2db)
noticable
> at the
> Rx end?"
>
> That all depends upon how you define noticeable. If your s-meter is
sitting
> at S-9, and assuming that 6 db per s-unit is the standard, that would mean
> the s-meter would change from 54 db to 56 db - or 2 db over S-9. If the
> variation in signal strength is greater than that due to reflection, then
it
> would be difficult to detect a 2 db change and not noticeable.
>
> However, if the signal was at or near the noise level, then 2 db increase
> could make the signal more easily read. A 2db increase is like Christmas
to
> someone using a single yagi for moonbounce.
>
> 73, Colin K7FM
>
>
>
> --
> FAQ on WWW: http://www.contesting.com/FAQ/amps
> Submissions: amps@contesting.com
> Administrative requests: amps-REQUEST@contesting.com
> Problems: owner-amps@contesting.com
>
>
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 96 feet for under $1500!! http://www.anwireless.com
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
|