Tag Archives: Arrow beam

Boboyan Range vk1/ac-044 – losing part of a 2m beam, but finding a lost SPOT tracker – 3rd Dec 2022

Having activated Pheasant Hill a week earlier but driven past the trailhead for Boboyan Range I needed to return to this summit to make sure of an activation before the end of the year.

The weather was fine and sunny, typical early December in this area, so I arrived at the trailhead at the planned time, about an hour’s travel from my base in Canberra’s south. I gathered together my regular HF gear and added the FT817 and an Arrow 3el beam, carrying a camera tripod in front of my body attached to a strap of the backpack with a carabiner.

After about 15 mins climbing up the mild slope, I decided to stop and take some photos and also send a message to Andrew VK1AD via Signal, our preferred chat system. I noted that SOTAGOAT was telling me I had 800m to go horizontally and 44m vertically to reach the summit location.

One of the photos taken at the 44m point
Photo 2 – this one has the north east horizon in view
Photo 3

Arriving at the activation point within the AZ I set up the HF gear and then the 2m beam and the FT817. That’s when I realised I had mislaid half of the director of my Arrow 3el yagi. I had to use the antenna with only a reflector and driven element. It actually seemed to work quite well and showed reasonable directivity.

After the activation I packed up and then walked slowly downhill trying to find the missing half of the director. You’d think a purple coloured bit of tubing about half a metre long would be easy to find but the foliage was fairly thick in places (see pics above) and the only waypoint I could try to find was the place where I took some photos and sent the message about 44m below the nominal summit peak. Cutting a long story short, I didn’t find it and when I reached the car it wasn’t there either.

So feeling a little deflated I started the trip back to Canberra via Tharwa. At Tharwa I decided to stop at the little general store and get a cup of coffee and a sandwich.

While at the store I heard a customer explaining to one of the staff that she had lost her SPOT tracker the previous day. Her name was Cath. She was riding her bicycle from Melbourne to Canberra on the Hunt1000, a riding/camping event via the Kosciuszko National Park, expanding it to 1000 km, a few hundred km further than the direct road route. She was a rider in a group of around 100 who were in this event which was due to end at Canberra on that day, Saturday 3rd Dec.

But on the previous day she had lost the SPOT tracker which each rider had hired for the event.

As the staff at the store were unable to help her directly, I offered to help her find the tracker. I asked whether there was a website which showed the locations of each rider. Yes, in fact there was an app provided to each rider and as she now had phone coverage in Tharwa she was able to display the map with all the rider locations displayed.

We were able to see her apparent location on the map, at a location about 20 km to the south, where she had ridden on the previous day. So I said to her “that’s where your SPOT is, let’s go and get it”. She was grateful for the offer.

The map in the phone app gave the lat/lon of each rider, or to be more precise, the lat/lon of each rider’s SPOT. So copying the location from her app into the Garmin on my dashboard, we were able to see that it was about 2 km south along Old Boboyan Road after its intersection with Boboyan Rd. Driving to it, we stopped at the point where the GPS said we had arrived, got out of the car and picked up the SPOT off the road right next to the car. I didn’t say anything about it at the time, but I was so glad I had not run over it. I didn’t see it while driving but it was only about 2 metres from the driver’s door when I got out.

There it is!

So after driving her back to Tharwa with Cath holding her SPOT safely I bade her farewell and wished her a safe trip to Canberra, as she still had to ride about 30km in to a location in Canberra.

Cath and I outside the Tharwa store after finding the SPOT. Pic published by permission.

I heard from her the next day confirming she had completed the trip and was safely in a friend’s car returning home to Newcastle.

And my lost antenna part? Still not found. I went back to the scene a week later with Andrew VK1AD and we both searched for a while. We didn’t find it but I did lose my good sunglasses as well, somewhere on that hillside. Not a good day…

However, Andrew VK1AD is a very capable metal worker and was able to fabricate a suitable section of aluminium rod, tapped for the 5/32 inch threaded rod that Arrow antennas uses to connect the element halves. I’m very impressed and grateful as I doubt if I’ll ever find the original part.

Starting with a couple of lines across the end of the rod to find the centre, then using a centre punch, a 3.2mm hole was drilled into the rod using oil as a lubricant. Then the taps were used to gradually form the thread, three taps are used (Start, Intermediate and Plug). What incredible good luck for me that Andrew had a set of 5/32” taps and was so competent in using them. He took some photos of the process and I’ve included some here.

The element has now been tapped to accept the 5/32” threaded rod used to hold the element halves together.

The finished half element to replace the lost one

So although the original driven element section is still out there in that scrub, the antenna is restored to normal operation, thanks to some excellent work by my friend Andrew Moseley VK1AD. Thanks again, Andrew.

I’m working out a way to avoid losing elements en route to the summits in future.