ARRL

ARRL General Bulletin ARLB035 (2004)

SB QST @ ARL $ARLB035
ARLB035 W1AW 2004 Frequency Measuring Test set

ZCZC AG35
QST de W1AW  
ARRL Bulletin 35  ARLB035
From ARRL Headquarters  
Newington CT  November 11, 2004
To all radio amateurs 

SB QST ARL ARLB035
ARLB035 W1AW 2004 Frequency Measuring Test set

There's a new twist to the ARRL Maxim Memorial Station W1AW
Frequency Measuring Test (FMT). The 2004 FMT takes place November 18
starting at 0245z (the evening of Wednesday, November 17, in US time
zones), replacing the W1AW phone bulletin normally transmitted then.
Rather than measuring the transmission's carrier frequency,
participants in this year's FMT will attempt to accurately determine
the frequency of an audio tone. Engineer and ARRL Contributing
Editor Ward Silver, N0AX, says measuring an audio tone will
reinforce understanding of the relationship between carrier
frequency and the components of a transmitted signal.

"The carrier is suppressed for SSB signals, leaving only the
sideband components," Silver explains in "The FMT Strikes a New
Tone," in November QST. "The frequency of components of the
modulating audio signal is preserved as the difference between the
carrier frequency and the transmitted component. A single modulating
tone results in a single transmitted component."

W1AW will make the 2004 FMT transmissions on 80, 40 and 20 meters.
The FMT will begin with a general W1AW "QST" starting at 0245z sent
simultaneously on the three W1AW transmission frequencies. The test
itself will consist of three 60-second tone transmissions on each
band, followed by a station identification. The whole test will run
for about 15 minutes and will end with a station ID.

The tone frequency will be the same on all three bands.

During the 2004 FMT, W1AW will indicate the band on which
participants should measure. After the initial call-up, W1AW will
begin the test by announcing, "Now 80 meters." Except for the tone
transmission, all transmissions will be voice. Frequencies are 3990
kHz (LSB), 7290 kHz (LSB) and 14290 kHz (USB), and all frequencies
will be accurate to at least 0.1 ppm (eg, 3990, +/-0.4 Hz).

Submitted reports should include name, call sign, location, time of
reception and, of course, the tone frequency. Those using an
indirect measurement method also should include calculations showing
how they arrived at the tone frequency. For additional details on
indirect and direct measurement methods, see Silver's article "The
ARRL Frequency Measuring Tests," on the ARRL Web site,
http://www.arrl.org/w1aw/fmt/0210051.pdf, or in October 2002 QST.

Send entries postmarked by Friday, December 17, 2004, to W1AW/FMT,
ARRL, 225 Main St, Newington, CT 06111. Separate reports for each
band are welcome. All entrants qualify for a Certificate of
Participation. Those coming closest to the measured frequency will
be listed in the web test report and get special recognition on
their certificates.
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