An emergency paging system presents a safety risk

New Zealand's Radio Spectrum Management (RSM) report that the use of 900MHz radiocommunication systems manufactured for the USA continues to be an occasional source of interference to cellular services in New Zealand.

They say a recent investigation found that interference to a cell site was being caused by paging devices operating in the 902MHz to 915MHz frequency band allocated to the cellular service provider.

While devices are available on acceptable frequencies higher in the 900MHz band (921.5MHz to 928MHz), the band from 902MHz to 915MHz is available in New Zealand only for mobile phones, and the band between 915MHz and 921.5MHz is available only at extremely low transmitter power (less than 3 microwatts).

Ironically, while the paging devices were installed to provide an emergency calling system for a retirement village, their operation posed a risk to mobile phone services through a nearby cell site, and may have put emergency calls at risk.