VK5RWN D-Star repeater site antenna tower replacement.

Back in mid August 2017, the tower supporting the antennas for the VK5RWN D-Star repeater system was damaged during the big blow that accompanied the storms. The tower, which was a section of a Hills Telemast bolted at the roof line of the communications hut, has been in service for about 27 years and was in good order. It appears that the wind loading had been exceeded during the August storms and the tower was bent just above the roof line of the building and the top section with the antennas was approximately 30 degrees off the vertical.

Well, no option, it had to be replaced!

The working bee at the VK5RWN site was scheduled for Tuesday 19 December 2017.

Ben VK5BB was at the site around 0845 hrs local time and the other members of the work crew arrived shortly afterwards.

Apart from initial preparations, and the OH&S site survey, the first job of the day was to erect the scaffolding, on the roof of the building! Gave us very easy access to all antennas for disassembly. The scaffolding was also used for the reassembly, thereby minimising the need to actually climb the tower, though Colin VK5ACE later did, to re-mount the 2m antenna at the top.

From there the antenna equipment was easily removed and the bent tower was cut off just above the bend in the tower (just above the roof line) and the tower easily removed. The coaxes were laid out to one side so as not to be damaged and ready for re-installation.

Whilst the old tower was being removed, other members bolted the new tower sections together ready for erecting. The new tower is two sections of Hills 330mm Butt Section mast, with additional plates fitted at the join of the two sections to provide some additional strength at the join.

The top end of the new tower was lifted (man-handled with ropes) above the adjacent hut and then the base lifted into position near where it was to be mounted. Using the ropes, the tower was then pulled upright, across the gap between the two buildings to its mounting position, loosely bolted in place whilst we marked out where the base bolts were to go, drilled and fitted the Dyna bolts and the tower was firmly bolted in place. Actually went in place quite well with a minimum of jiggling etc!

Lunch time! (about 1300 hrs local)

After lunch, the antenna cross arm and antennas were refitted, thanks to Colin VK5ACE, the main climber/rigger for the day. As the Wi-Fi dishes were refitted, the day started to get a bit blowy but the dishes were pointed approximately in the right directions. The 2m 7 element Yagi for the Broadcast Source transmitter was re-installed as a 3 element Yagi and pointed at Crafers. All coaxes were resealed, dressed and cable tied to the tower.

All antennas are back in their old positions, determined by the lengths of the various coax feeds. The tower, now 9m high, carries a 2m, a 70cm and a 23cm vertical “white stick” collinears, two 200mm Wi-Fi dishes and a 3 element 2m vertical Yagi.

Job done!

All equipment was turned on again and the various systems tested, we even had the Internet back on at the site, so we did get the dish right, either that or it has strong side lobes. (The Internet connection was previously still working even though the dish was pointed at the sky? A relay from the ISS??)

Clean up, and we were gone by 1700 hrs local.

The D-Star operations were checked at the site and later again from Ben’s QTH and all was good, including remote access to both the D-Star and the Broadcast computers.

Crew on site;

  • Trevor, VK5ATQ, roustabout and also supplied the scaffolding, (NERC member)
  • Rod, VK5ZRK, roustabout, (NERC member)
  • David, VK5MDF, roustabout, (NERC member)
  • Colin, VK5ACE, rigger, (AREG member)
  • Jeff, VK5IU, “supervisor” and roustabout, (AREG member)
  • Ben, VK5BB, project manager, 2nd climber/rigger, (AREG member)

Many thanks to the crew who helped during the day and especially Olga VK5FOLG, as she supplied a fresh cut lunch for all and delivered on site about 10 minutes before the lunch break.

Reports from the D-STAR users have reported a significant improvement of signal strengths at Balaclava and Mt Barker on 2m and from Hallet Cove on 70cm, so all appears to be good again.

Next task for the VK5RWN D-STAR system is the upgrade of the computer to a new 64bit system running CentOS 7 64 bit and the new G3 gateway software. This is scheduled for early in 2018.

Flight of Horus #43 – Postponed

Yet again the weather in South Australia has taken a turn for the worst with extreme weather and rain predicted this coming weekend.

As a result the flight of Horus 43 has been postponed until the weekend of the 25th or 26th of February.

Further announcements will be made closer to the date.

VK5VF beacons off air! – Restored

UPDATE 17th January 2016: The beacons have been returned to service after access to the site became possible following the Christmas break and a wayward circuit breaker was reset.


It is most unfortunate that during this period of VHF and up DX that the VK5VF beacons on 6m, 2m & 70cm have gone off air?

Yagi v Santa

There is a thought that the beacons may have been elf-otaged so as not to cause interference with the navigation system on Santa’s sleigh during high speed maneuvers required over the Christmas delivery period??

Alternatively, it is possible that there has been a total failure on the power feeder to the beacons cabinet. (pesky elfs have been busy!) Unfortunately due to the timing, it will not be possible to visit the site to investigate until somewhere around the 28th or 29th December 2015.

The beacon managers apologise for any inconvenience that this may cause.

Members of AREG wish everyone a happy and safe Christmas and New Year.


VK5RSB 23cm repeater service

Tuesday 8 December, the VK5RSB 23 cm repeater was given a little TLC by Colin VK5ACE, with support by Ben VK5BB. 23cm Rptr VK5RSB

There had been a number of reports that after a little time into a QSO via the repeater, that a noise was heard to be imposed on top of the QSO repeater audio. The noise and its source were not identified at the time and Colin could not account for it?

It was during a QSO between Ben and Colin that the noise was heard to come on and the comment was, “It sounds like a fan spinning up!”
Colin had a “Eureka” moment an said that it was most probably just that! After the transmitter has been on awhile and warms up, the fan cuts in and is most possibly modulating an internal 12 volt supply rail. This required a site visit to see what could be done.

Colin made all the necessary arrangements and scheduled a visit to the VK5RSB site.
Once at the site, the repeater was pulled out and put on a dummy load, the repeater was keyed up and sure thing, when the PA warmed up, the fan cut in and the noise was heard on the transmit signal.

Colin tried a number of electrolytic capacitors across possible points around the 12 volt fan supply and one point was identified where it appeared the noise was suppressed to the point it could not be heard. The capacitor was duly permanently soldered in, the transmitter tested, good no noise, covers put back on and re-tested and all appeared to be good, still no noise!

The repeater was re-fitted in the rack, cavities and antenna reconnected and the system tested to ensure that the fan switched on when the PA got warm and that there was no noise on the transmit output of the repeater. All was good, the site closed up and Colin and Ben departed.

So folks, there it is, all fixed, we hope?

Reports on the operation and observations of the 23cm repeater will be much appreciated.

CQ WPX & VK5 Parks Award activity underway!

The VK5ARG activation during the CQ WPX Contest and the VK5 Parks award activation by VK5QI and VK5AKH are underway now from the Coorong National Park. The bands are jumping and the team is having lots of fun camping out under the stars.

iOE1VKA20m is alive with activity during the contest, as can be seen from Mark’s SDR screen capture here. Not a lot of room on 20m when this was captured!

All the best boys and enjoy yourselves.