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[CQ-Contest] Clicks

Subject: [CQ-Contest] Clicks
From: hwardsil@WOLFENET.com (Ward Silver)
Date: Wed Mar 7 15:44:32 2001
Set up a spectrum analyzer to look at the output of a transceiver through
a suitable attenuator.  Set the transceiver to full output, full QSK and
key it at 30 wpm, all dots.  The analyzer should sweep plus/minus 100 kHz
from the center frequency.  The analyzer should be run with a narrow (500
Hz or less) and a wide (3 kHz) filter.  Sweep rate divided by filter BW
should be less than one-tenth the keying rate in order to get an accurate
measurement of any spurous products caused by the keying edges.  Also run
the tests in XIT and VFO A/B split mode at various separations.

To check a receiver - use a crystal oscillator keyed at a similar rate
into the receiver through a suitable attenuator.  First run the oscillator
through the analyzer tests above to establish a baseline.  Then tune the
receiver plus/minus 100 kHz from the oscillator frequency while listening
for clicks, watching the audio on a 'scope, and measuring both audio and
AGC with a good RMS voltmeter.

There are variations on the theme, but these are the basic tests.

73, Ward N0AX

 > I'm afraid that receiver-based tests are never going to persuade
 > manufacturers to clean up their act.  Why can't we contesters persuade the
 > ARRL to add an appropriately designed test or tests to their transceiver
 > reviews?  It would be even better (but maybe utopian?) if they could be
 > persuaded to run a comparison of the top half-dozen contest radios for
 > transient off-channel garbage on both CW and SSB.  W8JI's already explained
 > how this could be done from a technical standpoint, and the ARRL has proved
 > open to changing its test procedures in the past when presented with a good
 > idea...
 >
 > How about it, HQ?  Anyone reading the mail?
 >
 > 73, Pete N4ZR
 > Contesting is!
 >
 > The World Contest Station Database
 > is waiting for your input at
 > http://www.qsl.net/n4zr
 >
 >
 > --
 > CQ-Contest on WWW:        http://lists.contesting.com/_cq-contest/
 > Administrative requests:  cq-contest-REQUEST@contesting.com
 > 


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