In 1995 when Australian Bulk Minerals took over the open cut iron ore mine at Savage River, Coastal Electronics was asked to provide a radio communications facility for the site.
After Conducting a survey to establish a suitable site for the base station installation, and considering the previous Philips UHF system had served the site well for many years, we opted to install a two channel UHF talk through repeater system on the edge of the North pit. The equipment was enclosed in a steel cabinet mounted out in the open about five hundred metres from the Mill.
The repeaters used where Motorola GB300's used in conjunction with TELEWAVE 6 inch cavity diplexers. Though not technically remarkable the system performed well on site for about four years after which it was all moved into a new electrical switch room facility opposite. As the mine expanded into other areas, black spots began to develop, a second base station was clearly needed but, with the topography of the mine continuously changing there was no suitable place to locate a permanent facility. Our solution was to build a transportable communications platform, which was duly done using a modified box trailer to contain all the radio equipment and batteries and upon which was mounted Three eighty watt solar panels and an RFI OA-40 offset Dipole antenna Array.
The equipment consisted of a TAIT T2010 25 watt repeater and 1 watt 404/413 mhz link which relayed voice traffic back to the main repeater site, this facility is still in use today some thirteen years later.
In 2008 the mine had expanded to such a point it was obvious that extra channel capacity was needed to alleviate the growing pressure on the two way system. A series of consultations began with mine management to establish what features they wanted from their expanded radio network. After roughly six months of deliberation a well considered plan emerged, and the go ahead was given to design, install and commission a radio facility which provided:
- three extra channels - (totalling of six duplex repeater channels)
- enhanced redundancy
- emergency broadcast
- blast broadcast
- traffic monitoring
Fortunately the mobile mine fleet had been steadily moving away from the channel limited Motorola M120 and Maxon PM100 radios installed previously, to the newer GME TX3800 series radio which had a 99 channel capacity, so the mobile fleet was all ready for the expansion.
We installed a five channel TX RX TP4055 Multi-coupler which combines five, fifty watt Vertex VX9000R repeaters in to an RFI BA-80 UHF Omni-directional antenna array. A repeater to service Mill maintenance was also installed using a GME RP3800. To achieve the blast and emergency broadcast facility which enabled all personnel to be contacted no matter what channel they where using, we used an OMNITRONICS smart radio interface (SRI) coupled with two GME TX3800 dedicated receivers. The SRI takes care of all the audio routing and signalling necessary to pass information and control to the six repeaters.
Radio traffic monitoring is achieved first by programming into each vehicle and machine radio an identification number (ANI). The ANI is sent each time the radio transmits. In the Mill control room we fitted a GME TX3800 receiver programmed to decode the ANI's and export the received data to a computer which logs all radio activity. If an emergency call is sent, the terminals alert the mill controller, and displays all relevant information.
Grange Resources Savage River radio system now uses fifteen channels, and extensive use of mobile "voting" ensures that operators don't have to constantly change channels when moving around the site. Twenty percent of the radio traffic is done using five watt handheld radios, which also use voting.
The system was installed and operational in December 2008, however due to the takeover of the mine by Grange Resources, was not commissioned until February 2010.