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We have received notification from ACMA that our frequencies for the new Mt Eckersley repeater will be 146.875 MHz TX (user receive) and 146.275 MHz RX (user TX).

The link frequency will be 449.875 MHz but users won’t need to worry about that.

John VK5DJ
Repeater coordinator

The Naracoorte fence has been removed, not only does this tidy up the site but it also means that the Council people who tidy the whole site can also mow closer to the the repeater site – with the exception around the tower. I guess we’ll look to the NARC to poison regularly.

This will be great for the repeater maintenance team as they will no longer have to wear pith helmets when entering the area.

 

 Friday 1st. May 2020 at 7.30 p.m. sharp.

Please have a look at this article from the A.B.C. first.

https://www.abc.net.au/news/2020-03-04/australias-first-moon-bounce-schocked-us-experts/11339552

Once you have read that one open this file.

and the follow up by reading this one.

Thanks to Brian VK5VI for arranging the cabinet and President Peter for getting it from the VK5RHO site.

The solar charger will be mounted at the top on the non removable back of the cabinet. Below this will be the repeater for Mt Eckersley which will be on 19″ mounting holes. The cabinet is quite wide so the right hand side of the 19″ mount is on a bar that is fastened from top to the horizontal bar. This leaves about 200mm gap at the right for limited access.

Peter plans to cut an access port in the rear of the cabinet behind the repeater. Normally this will have a covering plate attached by bolts with captive nuts. The cover will maintain the vermin proofing. Rear access to plugs, antenna connections etc is necessary as Tait equipment is quite heavy and difficult to remove from the cabinet if only one person is present.

In the lower section will be placed the 4-6 cavities (until we have tested we won’t know how many we’ll need) and the battery.

We are still waiting on the allocation of frequencies although the callsign VK3RSW has been confirmed.

The repeater controller at The Bluff (Mt Gambier end) only has capacity for one repeater and two RF linking ports. The links were occupied (one to Mt Benson [Kingston ] and the other to Naracoorte) a solution was needed to supply a third RF link to Mt Eckersley.

The simplest solution was to take one link (that to Mt Benson) and split it into two with one going on to Mt Benson and the other to Mt Eckersley.

This required a new sub-controller to be designed and built.

The sub-controller would have most of the facilities of the main controller but control would be completely separate from the main via DTMF tones with a separate code access.

The sub-controller was designed and after much checking and consultation boards were ordered and supplied. One board has been populated with components and John 5DJ has preliminary software working. This is most encouraging as PCB design is always fraught with mistakes but fortunately so far all seems to be satisfactory.

Brian 5VI has been occupied building the hardware component of the project.

Fortunately we have a spare almost completed RF subrack on hand and all that is required is some additional wiring. This will be the main component housed at The Bluff end of the link. It will have the two RF links (to Mt Benson and Mt Eckersley) and the sub-controller module. Both RF links will be Tait T85x Series II (synthesised) modules).

For the Mt Eckersley site the RF equipment will be housed in one 19″ subrack and will contain the RF link (to The Bluff), the local repeater, and the repeater controller. All radio gear is modular and should a fault occur a replacement module can easily be fitted and the faulty module returned for repair. This will almost always eliminate the need to carry test gear to site.

To reduce site power consumption all RF equipment will be of the Tait crystal-locked variety although provision will be made to replace with synthesised equipment in emergency cases.

Current status is the Mt Eckersley radio subrack is being manufactured, is work-in-progress.

We have sourced a vermin-proof lockable cabinet which will house all radio, duplexer cavities, and battery-charging equipment and which will be available once travel restrictions are lifted.

Brian and John

VK5VI/VK5DJ

5^th April 2020

On Friday evening of March 3^rd 2020, amid the COVID-19 pandemic where all gatherings and meetings are banned, SERG held its first ever meeting over its 2m repeater network.

Chaired by the President, Peter VK5BE, and assisted by Secretary Col, VK5HCF, a total 24 stations participated, plus 1 apology.

As the first Friday of each month is normally an “Activity Meeting”, the meeting commenced with an episode from the ARRL podcast “The Doctor is In”, chatting about various antennas, following by the latest VK6 News Broadcast, which discussed numerous topics.

This was followed by all those present having an opportunity to comment about the meeting and forward suggestions about future meetings. It was agreed by all that this format should become a regular feature of our Clubs activities and now look forward to different ways of presenting activities via the repeater network.

Peter VK5BE

Added note from VK5DJ

David VK5HDW made a suggestion we should have a get together each Friday night that is not an activity night or business meeting.

Next Friday 10/4/20 at 7:30PM there will be a quiz night. A mixture of general knowledge and ham questions. Have a pen and paper handy to write your answers. We’ll mark our own at the end of the quiz.

First prize a roll of toilet paper to be awarded at the first face to face meeting after the crisis. You’ll have to hold on till then.

Tom, VK5NFT has been busy on his day off. His trusty whipper snipper has cleaned up the yard.  A poison follow up will happen soon from those with a supply of suitable poison.

The webmaster is told that no hippopotamuses or giraffes were found in the long grass, not that they would have survived Tom and his whipper snipper.

Our new VK5RMG home can be seen on the right.

At long last the Naracoorte 2M antenna has been replaced. It was almost a year ago that we discovered that the SWR on the 2M antenna was 2:1. Almost certainly one half of the system was broken away or corrosion had affected the system.

Late in 2019 the Naracoorte Club (NARC) agreed to pay for a new commercial  antenna and this was purchased and tested at VK5BE’s shack. It worked fine and was then disassembled and prepared for installation on a length of aluminium scaffolding purchased by SERG.

Finally the big days arrived with two possible dates for the crane, 13 or 20 March 2020. Winds were high on the 13th so the crane was booked for the 20th. The crane arrived on site at 9:00AM. The cost of the crane will be paid by SERG, safety was the prime consideration.

After checking the coax was fine by placing a dummy load at the top of the coax and testing for SWR from the bottom, the working bee began in earnest. Norbert VK5MQ was in charge and worked in the basket with the rigger.

By 10:45AM the pole was in place but winds had become too high to work safely so it was decided to call it off until 3:00PM in the afternoon.

Work continued at 3:00PM. By 5:00PM work was completed.

The antenna was tested from ground level with an immeasurable return loss and the repeater was put back on air. The LimeFM FM transmitter was also put back on air. LimeFM rent some tower space from the Naracoorte Club and their two folded dipoles can be seen lower on the tower and a 3 element Yagi for their link from the Bluff.

Here are some photos of the action taken by Peter VK5BE.

Surprisingly there does not seem to be any interaction between our installation and the LimeFM 100W transmitter/receiver. A condition for the LimeFM owners use of the site is they do not cause interference to us. So far they don’t.

It’s a good outcome and signals around the area do seem to be up. Time will tell.

Peter VK5BE and Col VK5DK travelled to the site today (Friday12/3/20) and switched on the 230VAC from our own meter. We now have lights and power for the repeater which is now completely out of the Gambier Electronics building. It’s nice to be independent.Thanks for arranging the power Norbert VK5MQ.

Door is master keyed the same as Mt Benson and the power box cover repaired. Thanks to Tom VK5EE we have the lock fixed on the cabinet too.

We are planning to put a chair, broom and rubbish bin in the building and we are looking at a few basic bits and pieces for repair jobs – mostly to be prepared as we often go on site and then find we don’t have a Phillips head screwdriver, a meter or a thingamejig.

Col will be returning to mow and poison the grass to make things look better in the yard, currently there could be a rhinoceros or giraffe hidden in there somewhere, not to mention the tiger snakes.

Current plan is to seek permission to put a separate gate in the perimeter fence to separate us completely from the GE building.

The working bee to install the new antenna at Naracoorte on Friday 13/3/20 has been postponed due to high winds predicted.

At this stage the crane has been booked for next Friday the 20th March. Attendance by the workers by 8:00AM with the crane arriving at 9:00AM.