Interference to commercial radio services often involves economic impact on business with all parties seeking an early and cost effective solution. These often involve complex problems and should be referred to Radio Spectrum Management (RSM) after maintenance checks have been conducted to eliminate equipment faults.
Identifying commercial Interference
Interference affects commercial services in the same way as it affects radio and television reception.
There are a wide range of commercial services where harmful interference may be described as any effect that disrupts the operation of the service. Commercial users are encouraged to contact their technical service agents or in-house radio engineering staff at an early stage to evaluate the interference.
This website has a list of approved radio engineers who may also be able to assist.
How to avoid commercial interference
Following correct installation practices for radio frequency equipment is a must. It is important to install radio equipment in accordance with the manufacturer’s installation instructions.
Ensure the equipment is operated in accordance with the licence conditions. These will have been determined by a radio engineer who is certified and experienced to do so.
Only operate the service at the location/s specified and in the specified geographical areas. Many services are licensed on a shared basis where interference must be tolerated.
Only use approved equipment for the type of service in question.
At shared radio station sites install equipment in accordance with AS/NZS 5070.2:2008 “Siting and operation of radiocommunications facilities - Guidelines for siting of radiocommunications facilities: VHF, UHF and SHF” as applicable.
Ensure your radio microphone cannot be jammed on. Always return it to its holder and do not throw it on the seat.
How to fix interference
Commercial users are encouraged to contact their technical service agents or in-house radio engineering staff at an early stage to evaluate the interference.
This web site has a list of approved radio engineers who may also be able to assist.
Depending on the type of licence and service agreement RSM may be able to assist in the location and correction of interference cases. Before this service can be activated the licensee is required to have engaged their technical staff or agents to check that the interference is external to any in house equipment faults. Please contact RSM on 0508 RSM INFO (0508 776463) during working hours if you require assistance.
For emergencies after hours affecting safety of life or property please phone the 24 hour call out number 026 106091 and you will be connected to our paging service. Please do not phone this number unless the situation is serious.
Types of interference
Interference sources described in the television interference and radio interference sections of this web site can also cause interference to commercial services.
In addition common forms of interference to commercial services are:
- Incidental long range signals due to ducting and refraction often caused by stable periods of hot weather associated with high pressure weather systems.
- Knife edge diffraction caused by the terrain signals travel over i.e sharp edged mountain terrain is a common cause.
- Intermodulation products due to the mixing of two or more strong signals and the re-radiation of the mixed products. Often caused in unprotected transmitter output stages. See AS/NZS 5070.2:2008.
- Service mobiles operating on high locations may access other geographical areas serviced by a different system using the same frequency.