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On November 15, 2006 at 9:45 PM EST, W1AW sent a series of tones (and Morse Code) on three (3) amateur bands. The event did not give out the exact frequencies on which W1AW was transmitting. The purpose of this "test" was for amateurs to measure as close as possible the transmitted frequencies. One of the goals was not only to exercise the capabilities of amateurs to properly measure frequency, but also to measure their understanding of the characteristics of a signal.
(For more information, please see The 2006 ARRL Frequency Measuring Test, November 2006 QST, page 50, or http://www.arrl.org/w1aw/fmt/2006/2006fmt.pdf.)
What made this year's FMT a little different was the addition of a West Coast Run. Thanks to Michael Fahmie, WA6ZTY for his transmitting a signal on 40-meters just after the W1AW Run. His transmission was used to supplement W1AW's, and to provide a "signal" for stations wanting to participate in the FMT, but would otherwise not have copied W1AW.
For the test, W1AW used two (2) Icom IC-756Pro II transceivers and one (1) Ten-Tec Orion I. The two Icom radios were feeding Harris RF-3230 power amplifiers. The Orion was feeding a Command Technologies HF-2500C 40-meter amplifier. Each amplifier was running approximately 1kW. The exciters were keyed simultaneously using the standard W1AW bulletin/code practice program and keyer matrixes. The test consisted of three 60-second key-down transmissions for each band, followed by station identification.
Amateurs who are familiar with the W1AW FMTs will notice that the measurements are not out to the 100th of a Hertz. The reason for this is because the stability of the signal out to the 100th of a Hertz couldn't be verified. This is due in part because Harris exciters are no longer used for the FMT (in addition to regular broadcast duties). While the frequency counter pretty much "sat" at any one frequency at the 10th of a Hertz place (short-term) it varied past that.
The frequency for each band was measured using a Hewlett Packard 5345A Frequency Counter, with a 10 MHz signal reference supplied by a Hewlett Packard Z3801A GPS/Frequency Standard. Dunestar Band-Pass filters were used between the measuring antenna and frequency counter. Each filter was manually placed in line for each band measurement.
The antennas used consisted of a dipole for 160-meters, a cage dipole for 80-meters and two (2) 40-meter yagis fed in parallel. In the case of the 40s, 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/ . (Please note that this list will soon be updated.)
The frequencies on which W1AW and WA6ZTY were actually transmitting are as follows:
160 meters: 1854317.5 Hz
80 meters: 3587117.5 Hz
40 meters: 7038804.9 Hz
WA6ZTY - 40 meters: 7028351.47 Hz
With the exception of when the Icoms and Ten-Tec and various amplifiers were being used for the morning code practice transmission that day, and the regularly scheduled transmissions that began at 4 PM EST as well, the exciters and amplifiers were left to idle throughout the day. (In other words, they were not shut down any time between scheduled transmissions). The measuring equipment and GPS frequency reference were left on (idling) the start of that week (Monday, November 13).
Throughout the day (and the few days before), 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.
Here is a breakdown of the WA6ZTY FMT station (information provided by Mike, WA6ZTY):
From top to bottom, the contents of the Frequency Standard Rack pictured here (with Mike, WA6ZTY standing to the side):
1.) Homebrew 26 volt DC power supply with internal battery backup. Keeps the ovens warm even during power failures.
2.) HP-107BR 5 MHz Quartz Frequency Standard. This one has an aging rate of less than 5 parts in 10^13/day.
3.) HP-103 1 MHz Quartz Frequency Standard. This one ages at about 2 parts in 10^11/day.
4.) HP-113 Clock. Takes 100 KHz input from standard, divides to 1 KHz to run synchronous clock motor. Provides 1 PPS scope trigger output.
5.) HP XY Oscilloscope. I use it to compare the WWV time tick with 1 PPS from clock.
6.) HP-114 Time Comparator. Takes signals from clock and standard to generate delayed precision sweep voltages to XY scope.
7.) HP-5328 500 MHz Frequency/Period Counter. I use it to measure the time difference between my 1 PPS and 1 PPS from GPS.
8.) HP-5245 Frequency Counter with HP-5263 Time Interval Plugin. I think I have the entire set of available plugins for this workhorse counter.
9.) HP-5105 Frequency Synthesizer, 0.1 MHz to 500 MHz in 0.1 Hz steps.
10.) HP-5110 Synthesizer Driver. Synthesizes a couple of dozen fixed frequencies required by the HP-5105 (above). I don't use its internal frequency standard; I use the HP-107 to reference it.
11.) Boonton 230A RF Power Amplifier. It takes a signal generator output up to 4 watts output, handy for all sorts of strange things!
12.) Beckman WWV/WWVH HF Receiver. This is a crystal controlled vacuum tube receiver with selectable tone filters to favor the various tones transmitted by NIST. It has crystals for all of their standard frequencies.
There were 195 submissions. Entries came from 40 states (as well as some Canadian provinces and a station from the Canary Islands and from the Ukraine).
The breakdown of State by Band can be seen in Chart A. The breakdown by State can be seen in Chart B. The breakdown by Call Area is in Chart C. And, stations [states] that copied WA6ZTY can be seen in Chart D.
There were 105 entries on 160 meters, 154 on 80 meters and 103 on 40 meters. There were 45 entries for WA6ZTY.
Out of the 195 entries, there were 54 amateurs with submissions on all three bands. Out of these 54, only 14 stations measured all three bands, including WA6ZTY's transmission.
There were 97 submissions on 160 and 80 meters; 57 submissions on 160 and 40 meters; and 81 submissions on 80 and 40 meters. These are the reasons why callsigns may be listed on more than one band.
The calls are listed (by band) by how close the measurements came (+/- in Hertz). The listings are as follows:
Less than 1 Hz
1 Hz to 5 Hz
5 Hz to 10 Hz
Above 10 Hz
160 meters (Less than 1 Hz):
AA6LK, AA8K, AB8OU, AC8Y, K1JE, K2RJ, K2SM, K4BEH, K5BTK, K5CM, K8TK, K9PS, KA8LGI, KB1MH, KB7NIE, KD2BD, KD5TFD, KE9Y, KM1P, KN4GE, KV4R, KX9N, N1EO, N2TDT, N8AP, N8OB, NM5U, VE2IQ, VE3BBM, VE3CZO, VE3HXP, VE3OAT, VE3TLY, VE3ZRK, W1HGR, W1HKJ, W1LE, W2HV, W3JW, W4AVO, W4TVI, W8DL, WA1ABI, WA1RAJ, WA2IKL, WA3BDV, WB4KLJ, WB8GXB, WB9FIP, WJ2B, WØBR/3
160 meters (1 Hz to 5 Hz):
AA9DH, K4DSP, K4DXA, K4GK, K4KYV, K5LJ, K8ZEC, KA7OEI, NA2X, W1PW, W1WV, W3NWJ, W3WJ, W4SHG, WA7TOF, WK4U, WOØW, WØPHD, WW4FLY
160 meters (5 Hz to 10 Hz):
K3KQ, K4GHP, KK8O, WBØLXZ
160 meters (Over 10 Hz):
AA4RP, AA5VU, AA9KH, K2TV, K3QC, K8YSZ, K9LZJ, KBØHL, KC2LFI, KF6LY, KG4QWC, KM4RK, KØCCM, N5DM, N8UR, N9XO, NYØO, VA3RMW, VE2ZAZ, W3MDM, W3TUF, W8IQ, W8QAP, WA3GOS, WA4FJC, WB2ART, WS3S
80 meters (Less than 1 Hz):
AA6LK, AB8OU, AC8Y, AE4XW, K1JE, K2SM, K2WU, K3KQ, K4DSP, K4GK, K4KYV, K5CM, K6APW, K6OQK, K8TK, K9PS, KA7OEI, KA8LGI, KB1MH, KB7NIE, KB9JJA, KD2BD, KD5TFD, KE9Y, KF7KN, KIØLS, KM1P, KØPF, KX9N, N1EO, N2TDT, N5PWG, N6TP, NM5U, VE2IQ, VE3BBM, VE3CZO, VE3HXP, VE3OAT, VE3TLY, VE3ZRK, W1HKJ, W1LE, W3JW, W4AD, W4AVO, W4TVI, W6OQI, W8DL, W8GF, W9TJ, WA1ABI, WA1RAJ, WA2IKL, WA7IRW, WA7TOF, WB4KLJ, WB4SBE, WB6BIH, WB6VRN, WB8GXB, WB9FIP, WBØBBE, WJ2B, WØBLK, WØBR/3, WØPHD, WS4S
80 meters (1 Hz to 5 Hz):
AA9DH, AB4XK, K2RJ, K4BEH, K4CXX, K4DXA, K5BTK, K8ZEC, KC2LFI, KK8O, KØCCM, KY5S, N1NAZ, N8AP, N8OB, NJ7P, W1PW, W1WV, W3WJ, W5PDB, W6IHG, W6MSU, W9DGI, WK4U, WOØW, WW4FLY
80 meters (5 Hz to 10 Hz):
K2TV, K4GHP, KN4GE, N4TUA, NA2X, W3NWJ, W4SHG, WA7MXZ, WØIRE
80 meters (Over 10 Hz):
AA4RP, AA5VU, AA8K, AA9KH, ABØOX, K5LJ, K6VRS, K8YSZ, K9LZJ, KB3LTT, KBØHL, KBØUAZ, KC8LMC, KG4QWC, KM4RK, KN4JN, KWØU, N5DM, N8UR, N9XO, NYØO, VA3RMW, VE2EZD, VE2ZAZ, VE3DIJ, W1LBV, W3TUF, W4GKP, W7KVI, W8IQ, W8QAP, W9GOC, W9JDH, WA2USJ, WA3GOS, WA4FJC, WBØLXZ, WB9NOO, WBØSWK, WN9GOC, WØMH, WS3S
40 meters (Less than 1 Hz):
AA8K, EA8NQ, K4CXX, K6APW, K6OQK, K6YAZ, KC2LFI, KØBHN, KØPF, NJ7P, W1PW, W6OQI, WA7IRW, WB6BIH, WB6VRN, WB6W, WK4U, WØBLK
40 meters (1 Hz to 5 Hz):
AE4XW, AG4ND, K2TV, K4GK, K5BTK, K5CM, K6JEY, K7KK, K8ZEC, K9PS, KA7OEI, KB7NIE, KB9JJA, KD5TFD, KM1P, KØCCM, KT6KT, N5PWG, N6TP, N8AP, NM5U, VE2IQ, VE2ZAZ, VE3OAT, W3CSW, W3WJ, W4AVO, W5UFZ, W6IBC, W7JAS, W8IQ, W9TJ, WA1RAJ, WA2IKL, WBØLXZ, WB4KLJ, WB9FIP, WBØBBE, WJ2B, WØBR/3
40 meters (5 Hz to 10 Hz):
AB4XK, AB8OU, K4BEH, KGØAL, KK8O, KY5S, W1WV, WS4S, WW4FLY
40 meters (Over 10 Hz):
AA5VU, AA9KH, AF4XL, K3QC, K4DXA, K4KYV, K4SCL, K5LJ, K8MEM, K8YSZ, K9JM, KBØHL, KN4JN, N4TUA, N5DM, N5LBZ, N8UR, NA2X, UT5RP, VE4YU, W1HKJ, W1LBV, W1LE, W3MDM, W3TUF, W4SHG, W9GOC, WA4FJC, WA8YNV, WB2ART, WN9GOC, WOØW
WA6ZTY (40 meters)
Less than 1 Hz:
AC8Y, K5CM, K7KK, KD5TFD, KGØHY, KIØLS, N5PWG, N6TP, NN7D, VE7BDQ, W1PW, W6BM, W7AMI, W7JAS, W7KVI, WBØLXZ, WB4KLJ, WB9FIP
1 Hz to 5 Hz:
K4BEH, K4DXA, K4KYV, K6APW, N5DM, NJ7P, VE4YU, W7DEB, WA7ZZB, WØBR/3, WOØW
5 Hz to 10 Hz:
WA3BDV, WI7B
Over 10 Hz:
AA6LK, K6VRS, K9JM, KC7JRY, KL1JP, N9CYL, W4QK, W5UFZ, W6IBC, W7HUY, WA4FJC, WØWGZ
Can amateurs expect another FMT in late 2007? It's up in the air. If there is one, it may again be similar to the 2006 FMT, or something completely different. There always exists the possibility of another FMT from the West Coast and possibly the Midwest. Given propagation factors, having a Test run from the West Coast or Midwest will give amateurs in those parts of the world an opportunity to participate in this event. Please note that these may not necessarily be coordinated by the ARRL, however.
As always, details will appear in upcoming issues of QST magazine, and also on the W1AW FMT web page.
Also available for the first time is the data of the submissions (in Excel format) for those who are curious about what the measurements were from various parts of the country. This file ontains ALL the entries, sans the callsign and address information.
We also hear from Dale Wentz, KB9JJA, who passes along the following web sites he's compiled that deal with frequency measuring and related topics:
http://www.baudline.com/download.html
http://www.febo.com/time-freq/fmt/technique.html
http://www.geocities.com/toddemslie/todds_tvdx_frequencies.html
http://www.qsl.net/dl4yhf/spectra1.html
http://sharon.esrac.ele.tue.nl/mirrors/zl1bpu/micro/Precision/index.htm
http://www.qsl.net/zl1bpu/PRECISION/index.htm
http://www.amug.org/~jthomas/wwvb.html
http://www.geocities.com/toddemslie/R8500offsets.htm
http://www.qsl.net/vk4cp/digipan.htm
http://www.realhamradio.com/GPS_Frequency_Standard.htm
http://www.febo.com/pipermail/time-nuts/2005-January/017677.html
http://www.pacificsites.com/~brooke/timefreq.shtml
http://www.thinksrs.com/downloads/PDFs/Manuals/PRS10m.pdf
http://www.algonet.se/~k-jarl/ssa/IARU/smeter.html
Thanks Dale!