The two metre Naracoorte repeater
Frequencies are 146.650 MHz output at 25 watts to the cavities and 146.050 MHz input with links 430.200 MHz at 12W to Willalooka and 442.375 MHz at 2W to The Bluff. The path to Willalooka is difficult due to the presence of hills. The equipment is built using synthesised TAIT units.
The VK5RNC site is located on Blackwell Road, on a small ridge, 100m ASL, about 5km SE of the town. The repeater belongs to the WIA and Naracoorte Amateur Radio Club and is an important component of the South-East repeater network. Maintenance is largely provided by the South East Radio Group. The repeater links to repeaters at Willallooka VK5RBT and The Bluff VK5RMG.
The guyed mast was removed on 23 September 2007 and the new tower installed in May 2008. This is a 70 foot windmill tower and is a much safer proposition even though it is slightly lower. The antenna was a 4 folded dipole array, but in early 2020 the antenna was replaced with a two dipole phased system. Unfortunately the 4 dipole system was suffering badly from corrosion but had completed good service for many years. The new antenna was co-funded by NARC and SERG. The costs included crane hire.
The repeater and link system is built from TAIT units obtained by the South East Radio Group. A set of cavities was prepared by Trevor VK5NC and tuned by Chris VK5MC in 2008. The controller is a 2019 design, dual link VK5DJ Mk2.
The South East Radio Group wishes to acknowledge a generous donation by John VK3FXJR which enabled SERG to purchase a number of surplus TAIT UHF link units and a VHF repeater. These were installed at Naracoorte and Willalooka by SERG and served us well until we updated the system on Monday 6th May 2019.
The photo here is of the old 4 dipole system at the tower top. About one third of the way down can be seen the small UHF beam carrying the link transmissions to the Bluff about 60km away and to the lower left is the horizontally polarised UHF link to Willalooka. The aircraft LED beacon light can be seen on the tower above the UHF vertical beam. Not required but an optional extra.
The previous tower being a guyed system resulted in the generation of noise caused by moving metal parts. In addition, climbing for antenna work was a precarious act for our volunteer workers.
In a similar manner to VK5RMG the two separate link frames have become one and as mentioned the controller has been replaced by a VK5DJ Mk2 controller which features support for two links and has meant the audio bridge is no longer required. This is a giant leap forward in terms of setting audio levels and simplification of the system. The new controller also has the capacity to send a 1KHz tone, at 3KHz deviation. This tone can be remotely triggered thus enabling the setting of levels on remote receivers. With both links and repeater in one small rack the entire system makes for a tidier setup.
Many aspects of controller operation can be changed at the site with a plugin keypad and LCD or by remote control using DTMF.
CTCSS at 91.5Hz is on board but not turned on. An audio recorder is not present for the generation of messages or an audio callsign although the controller supports one if added.
The club is especially appreciative of the work done by Brian VK5VI for wiring the two chassis, installing all the chassis components including loading PCBs and generally being a great supporter of the project at considerable cost of time and his back pocket.
The new system was installed on Monday 6/5/19 by:
Col VK5DK, Peter VK5BE, Brian VK5VI, John VK5DJ, Ross VK3KBO and Phil VK5PCL.