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 Previous: ARRL.NET Traffic Blocked by Comcast |  Next: Radio History is Made at WRC-03 with 7-MHz Realignment Compromise |
By Rick Lindquist, N1RL
Senior News Editor
July 3, 2003
US amateurs have been counting down the weeks and days. Now, the five new 60-meter "channel center" frequencies--5332, 5348, 5368, 5373 and 5405 kHz--have become available to US Amateur Radio operators. Given the constraints imposed on the five lightly used government frequencies, ARRL has been advising members to demonstrate their best operating behavior and to use common sense when operating under the new rules. The channelized allocation at 5 MHz marks the first new HF amateur band since the 1980s.
Given the constraints imposed on the five lightly used government frequencies, ARRL has been advising members to demonstrate their best operating behavior and to use common sense when operating under the new rules. The channelized allocation at 5 MHz marks the first new HF amateur band since the 1980s.
The only legal mode is upper sideband voice (USB), with a maximum bandwidth of 2.8 kHz (centered within each channel). The FCC has imposed a 50 W effective radiated power (ERP) limit, which its rules--§97.303(s)--define as the transmitter output in peak envelope power (PEP) multiplied by antenna gain relative to a half-wave dipole or the equivalent calculation in decibels. The Commission presumes that a half-wave dipole on the 5 MHz allocation has a gain of 0 dBd--technically its "free-space gain." This means that if you use a half-wave dipole--about 87 feet 3 inches for the "middle" channel--setting your transmitter's power output power at up to 50 W PEP should ensure compliance.
The FCC rules neither invite nor suggest creative ways for hams to justify running more than 50 W PEP transmitter power on the 5-MHz domestic, secondary allocation. The rules also impose a new record-keeping requirement on amateurs using antennas other than half-wave dipoles or their equivalent. "Licensees using other antennas must maintain in their station records either manufacturer data on the antenna gain or calculations of the antenna gain," the newest addition to the FCC's Amateur Service rules says. Amateurs can safely ignore feed line losses. In most typical ham installations, feed line loss at 5 MHz will be so small as to not have any practical effect on signal.
Under no circumstances may amateurs on 5 MHz radiate more than 50 W ERP in any direction, so those choosing to employ gain antennas will have to "do the math" and calculate their ERP. When in doubt, think simple, not complicated. The bottom line for most hams will be to erect a wire dipole, set their transmitter to 50 W PEP output and enjoy the new band.
Maxim Memorial Station Manager Joe Carcia, NJ1Q, says W1AW has no special plans to be on the air for the allocation's debut on July 3, but the station does expect to have 60-meter capability within the week.
For more information, see the 60-Meter FAQs posted on the ARRL Web site.
Working Stations in the UK
Amateurs in the US and the United Kingdom share one 5-MHz channel--5405 kHz. While it will be legal for US hams to work UK amateurs, US hams should keep in mind that UK operators are on the air specifically as part of an experiment and not for routine contacts.
UK licensees must obtain a special Notice of Variance (NoV) to use the 5-MHz channels available to them--5260, 5280, 5290, 5400 and 5405 kHz--and their access to the frequencies is temporary, ending in 2006. The RSGB's 5 MHz Working Group explains that the Radiocommunications Agency in the UK--in cooperation with the UK military--gave amateurs access on 5 MHz to enable propagation and equipment experiments to "assess and optimize inter-UK links rather than to provide additional spectrum for general amateur operation."
As UK amateurs are being told, UK-US contacts "need to be carried out in the context of experimentation and care taken to maintain transmissions within the channels allocated to UK amateur usage, whilst operating frequency offsets, where appropriate, to receive US amateur transmissions. UK amateurs are limited to 3.0 kHz bandwidth.
The RSGB 5 MHz Working Group says it neither encourages nor discourages international contacts on 5 MHz but emphasizes that--at least for UK NoV holders--such contacts need take place within "the context of experimentation."
Starting July 29, the RSGB's GB2RS began transmitting Amateur Radio news on 5 MHz as part of the continuing propagation investigations in the UK. The news transmission at 1130 UTC are on 5405 kHz.
For more information on the UK experimental activity on 5 MHz, visit the 5 MHz page on the RSGB Web site.
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