After a thorough trial, the Australian Communications and Media Authority has decided to make permanent ‘day/night switching’ arrangements to improve coverage of Brisbane’s 4KQ.
Since 2007, 4KQ, which operates on AM frequency 693 kHz, has conducted day/night transmitter power switching trials in Brisbane from Wynnum Road, Wynnum West. These trials have seen a significant improvement in the coverage of the 4KQ service into the Brisbane licence area.
The ACMA conducted public consultation on the proposal, released in January 2012, to vary the Licence Area Plan – Brisbane Radio – December 2000 (the Brisbane LAP). There was no evidence of problems with the day/night switching arrangements.
Day/night switching involves increasing the power of an AM transmitter during the day-time only. This takes advantage of the different ways that AM radio signals travel over distance, depending on whether it is day or night.
Restricting the power increase to the daytime only can improve the planned coverage, but is less likely than a night-time power increase to result in interference to very distant AM radio services operating on the same frequency.
The extended trial was intended in part to flush out any interference problems with the higher power operation, which can happen intermittently or during certain seasons.