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[AMPS] SB-220 IMPROVEMENTS

To: <amps@contesting.com>
Subject: [AMPS] SB-220 IMPROVEMENTS
From: dbr@alumni.caltech.edu (David B. Ritchie)
Date: Tue, 1 Apr 1997 23:50:49 -0800 (PST)
Whatever you say -- but when you are at a noise floor (like the 
moonbounce example) -- I find it hard to believe that 1db will do you 
much good -- what does that make your S/N ratio at that point?  An "S" 
unit is supposed to be about 5db or 6db as I recall and I can't tell any 
real difference between S2 and S3, S8 and S9, etc.  Can you? (other than 
by watching the meter bouce arond, of course).  Oh well 
Dave N7UE



On Wed, 2 Apr 1997, Roderick M. Fitz-Randolph wrote:

> >3db is barely detectable by the human ear
> >1-2 db can be measured by expensive instruments
> >2db hardly seems useful on any band (of course, the first 160db may be
> >VERY useful)
> >Dave N7UE
> ======================================================================
> Dave, what you say is absolutely true regards audio: 1 dB is the smallest
> amount of increase that can be detected with the ear.  However, in regard
> RF, it is my belief that you are way off base.  With the AGC of modern
> day receivers, your ear will hear virtually no difference in a 3 dB increase
> in signal strength.
> 
> On the other hand, we aren't talking about dB of audio!  3 dB of signal
> increase (we are talking RF now) will significantly plow through 3 dB less
> RF signals, desensitize the receiver through the AGC system and will appear
> to be the strongest sounding signal on that frequency.  If you truly doubt
> that, I invite you to contest with a 750 watt peak SSB signal (or CW for
> that matter) for a day during a weekend and then change over to 1500 watts
> of peak power and it my firm belief that you will have a significant
> increase in responding signals!  I have found that to be true over 4 decades
> of hamming.
> 
> What say others on the subject?  Am I right or am I wrong?
> 
> Rod, W5HVV
> 
> 
> 

David B. Ritchie, Esq.
D'Alessandro & Ritchie, P.C. -- Intellectual Property Lawyers
3521 E. Yorkshire Road, Pasadena, CA  91107-5432
818-683-8800 (TEL)   818-683-8900 (FAX)   dbr@alumni.caltech.edu


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