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Due to the drain on the solar charging the executive have made the following decision related to the C4FM repeater.

“In order to manage the power at the Bluff solar powered site, it has been decided to disconnect the Bluff UHF repeater from Yaesu-Fusion Aus-Repeater net as it’s default digital room. 

The Aus-Repeater net  is still available in room  24160.

This was a decision by the Executive Committee following an evaluation of the options for power management at the Bluff site.”

The repeater continues accessible for all local users, including its FM operation.

Norbert (VK5MQ) on behalf of the repeater committer and SERG executive.

VK5RMG UHF repeater Update 17/6/2026:

Nick VK5NJS and myself VK5AC, returned the UHF DR-2X repeater to the Bluff this morning and it is functional again on FM + C4FM and via wires-X from the clubrooms link.  

NO actual interference on 146.300 (with a 91.5 tone) was at ANY time measured or detected from this unit and performance was everything it should be.

The only problem detected was the failure of both repeater fans, the mid internal one having an o/c corroded DC cable, and the internal rear one being a random high current failure! This high current caused a SMD control transistor to split in two and let the smoke and carbon particles out in spectacular fashion. Some corrosion on the case body where the rear fan exits, internal fan mounting bracket, internal fan mounting screws and uncovered TX RJxx connectors in the internal fan path, all point to high humidity over a long period of time. I also had a chat to Guy about the problems encountered and his experienced problems. He would be interested to hear of any recurrence or additional information. 

Therefore both fans have been replaced and a fan controller installed that has an NTC sensor being bolted to the TX PA. This allows fan control directly related to the TX body temperature. 

<=35C = no fans.

>=35C = fans running at 50% speed.  (this copes nicely with testing the TX on continuous FM transmission (12 hrs) at either MID or HI power levels, where the fans cycle on/off every 10 minutes approx)

Fan speed ramps up to 100% over the next 10C range.  

<= 2C below 35C, fans will turn off.

I have done everything to stimulate and detect the problem, but nothing out of the ordinary occurred! 

Best theory is that it was long term heat related, no matter how improbable and impossible this might sound! 

The long “War and Peace” version of my notes will be available in paperback soon, or maybe just on the SERG web site 🙂 

Maxwell Osmond, VK5AC

Naracoorte repeater fault – May 17^th 2026

The proverbial failure of a 20 cent part . . . . . .

Following a report that the Naracoorte 2m repeater was ‘off the air”, Peter VK5BE & Nick VK5NJS travelled up to the site to investigate the reported failure.

Upon arrival, it was noted that the main power supply still had mains power, but no DC output, and the 12 volt back-up battery had discharged down to 10 volts where the repeater had shut down.  It was also noted that a “DC fuse fail” alarm was active on the front panel of the power supply.

The 30 Amp glass DC fuse was then removed & visually inspected & all appeared normal. However upon testing the fuse with a multimeter, it was found to be open circuit, despite appearing OK. The fuse was faulty without being blown.

Another fuse of similar rating was fitted to the power supply, & the repeater restored to service & all functions tested OK. A faulty 20 cent fuse had caused a total site failure.

Lesson learnt – don’t assume that if a glass fuse looks OK, that it is actually OK.

On Saturday 21st of March members of the South East Radio Group set up at picturesque Lake Leake, 35 Km NNW of Mount Gambier S.A. in order to participate in the 2026 John Moyle Memorial Field Day Contest.
Our aim was to be involved in the contest while enjoying a relaxed family day in the sun.

The weather was absolutely perfect with the only downside being the stiff breeze that started up later in the afternoon which caused a couple of members to roll up their awnings before any damage was caused.
Radio conditions were not great and for a while the ops experienced a lot of interference from nearby vehicles. That was partially overcome by reorienting the half wave end fed multi band antenna which was kindly supplied by Tim, VK5AV.
We must also thank club president Nick, VK5NJS for towing our club trailer to Lake Leake and then back home again.
A number of members had a spell on the radio using our club callsign of VK5SR, while the rest were quite content to sit in the shade and swap tall tales, lies and general gossip.

The camp ground was quite busy with a number of caravans on site and a large group of backpackers were camped at the Southern end of the grassy camp area. Fortunately, they were away for the day apple picking in local orchards and so caused us no bother. 
With a decent toilet block and a solid shelter containing  a free BBQ we were easily able to cook our sausages, burger patties, onions and whatever else was fancied.

Lake Leake used to be a very popular playground here in the Lower South East of South Australia and speed boat racing was a regular occurrence a few  years ago, but the water level has fallen to such an extent that the Lake is not even any good for canoeing now. It is fed entirely from rainfall and that has been lacking over the last few years.

All present thoroughly enjoyed the day and we will be doing more of this sort of club activity over the coming months.
A big thank you to Tim, VK5AV, for suggesting our participation in the John Moyle Field Day and helping make it a relaxed and casual event for all to enjoy.

Jack, VK5EBA, Tim, VK5AV, Owen, VK5HOS and Tony, VK5AGE setting up the half wave end fed multiband antenna.

Some of the members, (and partners), just enjoyed the social side of the day, (and the sunshine of course).

Tony, VK5AGE, Peter, VK5BE and Tom, VK5EE solving the world’s problems in front of the excellent shelter which contained the free BBQ.

Jack, VK5EBA and Tim, VK5AV on the radio in our club/s communication trailer, club president Nick, VK5NJS and Greg, VK5ZGY in the foreground (with Tom, VK5EE in the background).

On Tuesday 20/1/26 Nick VK5NJS and Norbert VK5MQ re-positioned the two metre clover leaf antenna for the 144.550MHz beacon.

Previously the beacon was seriously desensing the 2M repeater and we had found it necessary to turn the beacon off.

Rather than being less than 2 or 3 metres from the repeater antenna it has now been relocated  about half way up the tower. Desense has gone and the beacon is performing as it should.

John VK5DJ and Tom VK5NFT were on site for encouragement.

Thanks all.

Thanks to WICEN and Arno VK5ZAR here is an update of the VK5 Repeaters. 

Wow. What a great day it turned out to be.

The weather was anything but promising in Mount Gambier early but it turned out to be an almost perfect day at Lake McIntyre.

There were occasional gusts of wind but we also had patches of sunshine and it turned out to be an almost perfect day.

A record attendance of just under 30 members and a very relaxed day of conversations and a bit of playing radio.

Last Friday Nick, accompanied by Col VK5HCF, presented a box of craft beer to Brett Pittard, the proprietor of T.D.R.S. Tech. for his long time, (and ongoing), support by providing our Group with first class internet access free of charge.

Brett does this in order to honour the memory of his Dad, Phil, VK5HAM. (S.K.) who was a prominent member of the club a few years ago. Phil was an accomplished musician, a tech wizard and a man possessed of a very sharp wit. He contributed a great deal to the club over many years and is sorely missed.
Thank you Brett.

Now in testing mode at The Bluff and performing well.

Here are some details provided by Peter VK5BE.