Keep legal on 5MHz

| December 11, 2015

The RSGB Amateur Radio Observation Service has noted several examples of British JT65 and JT9 mode transmissions straying outside of the UK allocated band slots.

It is understood that software commonly used by UK licensees for the production of signals in both modes uses default 5MHz band preset frequencies of 5.357MHz for JT65 or 5.359MHz for JT9.

After applying the audio offset to the AFSK signal in JT65 mode, using these presets will, in the majority of cases, cause the transmission to fall outside of the upper band edge of the UK allocation of 5.354MHz to 5.358MHz.

In the case of JT9, if the default of 5.359MHz is used then all transmissions will be outside of the UK allocation.

Users of these modes are requested to check that their transmissions fall within the allocated spectrum.

Category: Front Page News, GB2RS Headlines