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On November 17, 2004 at 9:45 PM EST, W1AW transmitted an audio tone of known frequency on three (3) amateur bands. The event did not give out the exact tone frequency W1AW was transmitting. The purpose of this "test" was for amateurs to measure as close as possible the transmitted tone frequency. One of the goals was not only to exercise the capabilities of amateurs to properly measure frequency, but also to measure (if you will) their understanding of the characteristics of a signal.
(For more information on this, please see The 2004 ARRL Frequency Measuring Test, November 2004 QST, page 52, or the ARRL web page at, http://www.arrl.org/w1aw/fmt/2004/04fmtsilver.pdf .) Additional information can also be found at, http://www.arrl.org/w1aw/fmt .
Participants have already received their initial letter with the results. The Certificate of Participation followed shortly afterwards.
How were the transmissions performed?
For the test, W1AW used three (3) Harris RF-3200 exciters and Harris RF-3230 power amplifiers. Each amplifier was running approximately 1kW. The exciters were keyed simultaneously using the standard W1AW bulletin/code practice program and keyer matrixes. The audio tone was fed into an AMR-64 6-channel mixing board. The board fed the signal into the Audio Matrix, which also simultaneously fed each exciter. The test consisted of three 60-second key-down (tonal) transmissions, followed by station identification.
The tone frequency was measured using a Hewlett Packard 5345A Frequency Counter, with a 10 MHz signal reference supplied by a Hewlett Packard Z3801 GPS/Frequency Standard. The Audio Signal Generator was a Heathkit IG-5218 Sine/Square Signal Generator
The antennas consisted of a Cage Dipole for 80-meters; two (2) 40-meter yagis fed in parallel; and two (2) 20-meter yagis fed in parallel. In each case, one antenna was pointed towards the NNW and the other towards the SSW. The complete W1AW antenna list can be found at, http://www.arrl.org/news/features/2001/07/30/1/ .
The frequencies (suppressed carrier) on which W1AW was transmitting were as follows:
80 meters: 3990000 Hz LSB
40 meters: 7290000 Hz LSB
20 meters: 14290000 Hz USB
The audio frequencies measured (calculated) at W1AW for each band were as follows:
80
meters: 1105.02
Hz (signal measured at 3988894.98 Hz)
40 meters: 1108.26 Hz (signal
measured at 7288891.74 Hz)
20 meters: 1116.77 Hz (signal
measured at 14291116.77 Hz)
A single audio tone (measured at 1114.1 Hz) was fed simultaneously into each Harris exciter throughout the course of the FMT. However, the exciters are separate units, and do not share a single local reference frequency (oscillator). Therefore, slight variations with the transmitted signals would naturally exist, causing the measured signals to vary as well. This is why the above listed frequencies are not the same across the bands.
With the exception of when the Harris exciters were used for the morning code practice transmission that day, and the regularly scheduled transmissions that began at 4 PM EST as well, the exciters were left to idle throughout the day. (In other words, they were not shut down any time between scheduled transmissions). The measuring equipment, GPS frequency reference and signal generator were left on (in idle) the start of that week (Monday, November 15).
Throughout the day, the exciters were tested to determine drift (stability-short and long-term). The drift was negligible. However, throughout the course of the FMT, W1AW also measured the signals (using Indirect Measurement) during each transmission, just to be sure.
There were 130 submissions. This is down approximately 39% from 2003 (with 214). Obviously, propagation had played a role (for example, there were only 9 entries for 20 meters). Entries came from 30 states (as well as some Canadian provinces and one amateur from South Africa). The breakdown of State by Band can been seen in CHART A. The breakdown by State can be seen in CHART B. The breakdown by Call Area is in CHART C.
There were 121 entries on 80 meters; 48 on 40 meters; and 9 on 20 meters.
Out of the 130 entries, only two amateurs--N9AB and VE3OAT--submitted results on all three bands. There were 48 entries with submissions on 80 and 40 meters, and 6 entries with submissions on 80 and 20 meters. (There were no 40 and 20-meter combinations.) This is the reason why callsigns may be listed on more than one band.
Callsign Lists
Unlike in previous years--when calls were listed by errors in ±ppm--for the 2004 FMT the calls are listed (by band) by how close (in Hertz) the measurements came. So the listings are sorted as follows:
80-meters -- Less than 1 Hz:
AA4MI AA4RP AA6LK AC8Y AF9A AK4GY K2SM K3KQ K3XY K3ZMA K4AQ K4CSO K4JAF K4VA K5CM K6HLH K6PFA K7JL K8CCE K8ZEC K9PS KA3ZYX KA7OEI KA8BDD KB3FGZ KB8MOU KB8TMG KC3ET KD5TFD KF9LS KG5JJ K0LR N1BC N1EO N4WL N5PWG N7EP N8AP N8ASB N8UR N9AB N9UH VE3HXP VE3OAT VE3ZRK W1ESK W3CSW W3JW W3NF W4NTG W4NTO W4OOY W9SE W9TJ W9TJ WA1MIK WA2DVU WA5LUY WA6JGM WA8YNV WB2CPN WB8GXB WD4KDN WJ2B W0BR/1 W0QE
80-meters -- 1 to 5 Hz:
AA5VU K5BTK KA2HDD KC2DMC KD2BD KG4ORA KG4QWC K0FNI K0LOA K0ZYA KV5R N1NAZ N2CKH N2QLQ N3IW N5DZ N6TP N9CYL NV0M W3FAY W3ZLC W5DZ W8GF WA1RAJ WA2NBT WA6VPJ WB5EXI WB9FIP W0AGC W0HBK
80-meters -- 5 to 10 Hz:
K4THE K8TK K8WK KD5JEM K0CCM KW5I N5OHL W7ISD W9GOC W9XAN WF0P
80-meters -- Over 10 Hz:
AB2NM AD5DT KA8WQL KB3HQW N2CG N9VWA N9XY VE2XL W4JON W8NNX W9ZJX WA3GOS WA9PYH W0CH
40-meters -- Less than 1 Hz:
AA4MI K5BTK K5CM KA7OEI KA7UKN KD5TFD KI0LS K0LOA K0LR KV5R N5FSF N5OHL N5PWG N7EP N8UR N9AB VE3OAT W3NF W5DZ WA5LUY WB8GXB W0QE
40-meters -- 1 to 5 Hz:
AA4RP AA5VU AA6I K4JAF K9PS KB8MOU N2CKH N5DZ N6TP W0HBK
40-meters -- 5 to 10 Hz:
KD5JEM KW5I N2QLQ W7ISD WA1RAJ WA6VPJ WB5EXI
40-meters -- Over 10 Hz:
AB2NM AD5DT KC9GPG KE7BZH K0CCM N6PE W8NNX WA3GOS WA5SLG
20-meters -- Less than 1 Hz:
K8ZEC N8AP N9AB VE3OAT ZS6BTE
20-meters -- 1 to 5 Hz:
W0BR/1
20-meters -- 5 to 10 Hz:
W8GF
20-meters -- Over 10 Hz:
K4CSO WA1MIK
Will there be additional Frequency Measuring Tests?
Amateurs may expect another FMT in late 2005. (That is the current plan as of this writing.) It may be similar to the 2004 FMT in that amateurs will have to measure a tone frequency. The question is still up in the air as to whether it may be feasible to have a "Test" from the West Coast. Given current propagation factors, having a Test run from the West Coast will give amateurs in that part of the world an opportunity to participate in this event. It may not necessarily be coordinated by the ARRL, however.
As always, details will always appear in upcoming issues of QST magazine, and also on the W1AW FMT web page.
