Site visit to Kellerberrin VK6RKN

Monday April 18th happened to be World Amateur Radio Day – and a group of WARG members decided to celebrate the day by travelling to Kellerberrin, about 200km east of Perth, for a day’s work on the VK6RKN repeater site. Trevor VK6MS and myself travelled up from Perth, Peter VK6PK joined us along the way from Wooroloo, and we met Bruce VK6LAW and Pete VK6FUN on site at the repeater.

This site had previously suffered a lightning strike, which did significant damage and put the 2m repeater off air. Whilst partial work had been done to restore the service, it hadn’t been previously possible to climb the mast and replace damaged antennas and feedlines. This was the main aim of the working party, and thanks to our combined effort – and particularly the work of Trevor VK6MS – we had great success on the day.

WARG recently was fortunate to obtain a donation of high quality low-loss antenna cable (LDF4-50 equivalent) from David, ex-VK6NFH. Prior to the working bee this was prepared and checked ready for transport to site and installation. Ray VK6ZRW had previously retuned the cavities, and a replacement antenna and the repaired repeater/cavities had already been transported to site and installed on test, thanks to the previous efforts of VK6PK, VK6FUN and Colin VK6ACT. A new UHF CB antenna was already on site courtesy of the shire, who had asked if we could investigate the CB repeater performance in consideration of WARG’s site access for the 2m repeater.

On the day, Trevor VK6MS scaled the 45m mast, and with the rest of us as ground crew, we removed and lowered the faulty 2m and UHF CB antennas, hoisted the new feedline aloft, and fitted replacement antennas, including a stacked phased-array dipole for the UHF CB, and a dual-band X-300 Diamond for WARG usage. The CB phased-array is all stainless-steel welded construction, and sits atop the mast, offering a greater degree of lightning protection in future. The WARG dual-band sits on an outrigger about a metre or so below the mast top, hopefully out of the firing line, whilst still achieving good height for coverage. The new feedline is secured with stainless cable ties and earthed top and bottom to the mast. At ground level the feedline entry point to the hut was improved with a new gland plate being fabricated and installed, along with a lightning arrestor at the entry point, and new internal cabling to the repeater and APRS equipment.

Due to the fading daylight, there was not time for a full spec-check and investigation of the repeater and APRS functions, but on a quick test, all was working to a reasonable standard. Mobile tests on the homeward journey showed the repeater coverage now extending westwards to Cunderdin and north to Baandee, with base stations in Merredin also being able to work VK6RKN. (On the down side, the coverage in the Perth Hills seems to have dropped off…but I would say that is outweighed by the local improvements…)

A big thank you to VK6MS for the climbing, and to Bruce VK6LAW, who used his local contacts to solve a number of problems on the day. Thanks are also due to VK6FUN, VK6PK and all others who donated time, effort or materials to make the day a success.

There is still work to be done – the APRS antenna (Diamond 2m colinear at about 15m level) is showing high SWR, which needs investigation, although the APRS is still working OK by all reports. The repeater’s RX mute setting is a bit high, and it still seems to be de-sensing on weaker signals at the fringes – plus the internal hut cabling could do with a bit of tidying up. All tasks for a future working bee…to be scheduled.

Reports on the coverage and performance of the repeater,  and APRS service would be appreciated, either on-air during WARG’s Sunday net;  via email, to secretary AT whisky alpha romeo golf DOT org DOT au – or come along to a WARG meeting and tell us about it!

73, and Best Regards,

Anthony VK6AXB
Secretary, WARG