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@rosenet.net>
To: CQ-contest reflector <cq-contest@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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