[CQ-Contest] re:Clicks-REAL numbers.

[James B. Neiger]

As far as I'm concerned, the REAL EXPERT has now spoken.  Thanks George for
the insight.

Jim Neiger
N6TJ/ZD8Z  (still laboring along with my trusty, and reliable, TS-950SD).
----- Original Message -----
From: George Cutsogeorge <w2vjn at rosenet.net>
To: CQ-contest reflector <cq-contest at contesting.com>
Sent: Friday, March 09, 2001 11:00 AM
Subject: [CQ-Contest] re:Clicks-REAL numbers.


 >
 > Here are some keying test results done with real radios and an HP spectrum
 > analyzer.  The radios were set up at full output power and were keyed at
40
 > WPM.  The spectrum analyzer was setup with a narrow bandwidth and very
slow
 > sweep time.  The dB levels given were measured at an offset of 1 kHz on
each
 > side of the carrier.  (Total bandwidth = 2 kHz.)
 >
 > Radio        dB down at +/- 1kHz
 >
 > Omni VI+           -50
 > 1000MP            -46
 > IC765                -44
 > Test                   -51
 >
 > The Test was done with an HP8640B signal generator keyed on and off at 40
 > WPM with a rise and fall time of 5 mS.
 >
 > This data shows that there really are sidebands out there which will be
 > heard by adjacent channel receivers.  This is a fact of life.  For
example:
 > An Omni VI+ is sending 40 WPM and is S9 +30 dB on tune.  One kHz away his
 > sidebands (clicks) will be down 50 dB, or about S6 to S7 on a calibrated
 > meter (not a typical S meter).  Since the receiver filter also has a
finite
 > bandwidth even with the best filters, the transmitted signal will appear
to
 > be even wider.  This assumes there is no blocking or IMD taking place in
the
 > rx or excessive phase noise in either tx or rx.  If there is, he will
appear
 > wider yet.
 >
 > It's interesting to me to see how little difference there is between these
 > radios.  Thanks for the suggestion N0AX.
 >
 > George, W2VJN
 >
 >
 > --
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