Cooperative Effort to Resolve Potential 70-Centimetre Interference Issue

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Cooperative Effort to Resolve Potential 70-Centimetre Interference Issue

The FCC, and the US Department of Defense are cooperating in an effort to eliminate the possibility of amateur radio interference on 70 centimetres to critical systems at White Sands Missile Range (WSMR) in New Mexico. The Defense Department’s Regional Spectrum Coordinator contacted the FCC in March, seeking information on whom to contact regarding detected amateur transmissions it believed could pose a threat to a critical WSMR system operating on 70 centimetres. The FCC, in turn, asked ARRL to be involved in the discussion and any necessary remedial efforts. It is to be noted that the Amateur Radio Service is a secondary service on the band.

Investigation revealed that the potential problem was not with individual operators or repeaters, but with RF control links at 420 – 430 MHz used to establish a linked repeater system within New Mexico.

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New RSGB EMF Calculator Available

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New RSGB EMF Calculator Available

A new version of the RSGB/Ofcom EMF Calculator v0.1.2-rsgb9c is available for free download on the RSGB EMF page

Ofcom has produced a guidance document explaining what radio amateurs need to know about the new EMF licence condition. It includes a handy compliance flowchart that shows you step by step what you need to do to carry out your Assessment.

The first step is to determine your station's EIRP, the RSGB's Calculator will help you work this out and give the required Average EIRP value. If this value is 10 watts or less then all you need to do for the Assessment is record the calculated value, nothing else.

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WSJT-X 2.4.0 Introduces New Digital Protocol Q65

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WSJT-X version 2.4.0 has introduced a new digital protocol called Q65, which is designed for “minimal two-way QSOs over especially difficult propagation paths,” the Quick Start Guide says.

“On paths with Doppler spread more than a few hertz, the weak-signal performance of Q65 is the best among all WSJT-X modes. Q65 is particularly effective for tropospheric scatter, ionospheric scatter, and EME on VHF and higher bands, as well as other types of fast-fading signals.”

The new protocol uses 65-tone frequency-shift keying and builds on the demonstrated weak-signal strengths of QRA64, introduced in 2016. User messages and sequencing are identical to those in FT4, FT8, FST4, and MSK144. Q65 employs a “unique tone” to sync time and frequency. “As with JT65, this ‘sync tone’ is readily visible on the waterfall spectral display,” the Guide said. “Unlike JT65, synchronization and decoding are effective even when meteor pings or other short signal enhancements are present.

Transmit/receive sequence lengths of 15, 30, 60, 120, and 300 seconds are available. According to the Guide, “Q65 will enable stations with a modest Yagi and 100 W or more and to work one another on 6 meters at distances up to ~1600 kilometers at most times, in dead band conditions.”