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 Previous: NTIA Study is Bad News for SAVI 425-435 MHz Proposals |  Next: ARRL In Action: What Have We Been Up To Lately? |
NEWINGTON, CT, Oct 31, 2002--The Frequency Measuring Test (FMT)--an ARRL staple for nearly 50 years--will return in early November. A FMT transmission will replace the W1AW SSB bulletin on November 7, 0245 UTC (Wednesday, November 6, in US time zones). The resurrected FMT will kick off a series of measuring tests.
"These tests will exercise the capabilities of hams to measure important operating parameters, improve their understanding of complex radios and give them a better mental picture of their transmitted signals," Contributing Editor Ward Silver, N0AX, said in an October 2002 QST article describing the art and science of frequency measurement. "The goal is a more technically aware amateur confident of compliance with FCC regulations." Silver's article, "The ARRL Frequency Measuring Tests," appears on page 51 of the October issue.
Do You Know Where You're Transmitting?
Today's amateurs tend to take for granted the accuracy of their transceiver's frequency readout. But, as Silver notes in his article, relying simply on a transceiver's digital readouts could mean part of your signal is outside the band edge--in violation of FCC Part 97 rules. Transceiver or receiver readout accuracy "depends entirely on the quality of the receiver's master oscillator," he points out in QST.
Of course, the increasing technical quality of amateur gear was one of the primary reasons for the decline and fall of FMTs in 1980. In prior decades, however, thousands of amateurs took part in the FMTs, and participation was required of ARRL Official Observer and Official Relay System stations. The first FMT, held in October 1931, employed three transmitting stations--W1XP at Massachusetts Institute of Technology, W9XAN at Elgin Observatory in Illinois and W6XK at Don Lee Broadcasting System in Los Angeles--and drew more than 200 measurement reports.
"Winners demonstrated better than 99.99% accuracy, and more than half received certificates for better than 99.90% accuracy," Silver reported--not too shabby for the state of the art back then. Among other things, the FMT pioneers were recommended to obtain or construct a frequency meter and make sure it had fresh batteries installed.
Silver's October QST article provides a lot of background information concerning on-the-air frequency measurement as well as details on the 2002 test. It also offers details on frequency-measurement techniques that participants in the 2002 FMT might want to consider.
The FMT 2002 Schedule
The 2002 FMT will begin at the appointed time--0245 UTC November 7 (9:45 PM EST November 6)--with a general Morse code "QST" from W1AW on four amateur frequencies. The test itself will consist of 20 seconds of carrier followed by a series of CW dits followed by a station ID. The test will last about five minutes and will conclude with a series of Vs and another station ID.
The approximate frequencies are 3580, 7047, 14,048 and 21,068 kHz.
FMT 2002 participants should include time of reception, measured frequency and signal report, as well as their name, call sign and location. Participants are encouraged to submit reports on more than one of the frequencies.
A Certificate of Participation will be available to all who send in reports. Those who come closest to the measured frequency will be listed in the test report and will receive special recognition on their certificates.
Send FMT 2002 entries postmarked by December 6, 2002, to W1AW/FMT, 225 Main St, Newington, CT 06111.
More information and
background on the 2002 FMT--including a link to the equipment
W1AW will use to generate the FMT signals--is available on the ARRL Frequency
Measuring Tests - Supplement page on the ARRL Web site.
| Previous: NTIA Study is Bad News for SAVI 425-435 MHz Proposals | Next: ARRL In Action: What Have We Been Up To Lately? |
