Mt Gawler VK5/SE-013

On Sunday the 27th of October, I activated Mt Gawler, VK5/SE-013 for the Summits on the Air Program.

I thought I’d kill 2 birds with one stone, as this date was also the day of our 1 year anniversary lunch for SOTA in VK5, to be held in at the Kingsford Hotel in the town of Gawler, just a short distance from the mornings activation. I thought I’d go down early, and knock over the summit before enjoying a nice meal and catch-up with the great bunch of VK5’s that participate in the SOTA program.

Not surprisingly, just as I got going 1st thing on the Sturt Highway coming down, I found myself driving behind a familiar vehicle…Larry, VK5LY was travelling in front in his distinctive Toyota Hilux, bristling with antennas! I had gathered Larry was on the way down for the VK5 get together, so I gave him a shout on the local repeater, and sure enough, he was heading down early to activate Mt Gawler as well!

Great minds think alike, and I was pleased that this was going to be a dual activation. Larry is great fun, and a very knowledgable fella as well…we chatted most of the way down to Truro and beyond on 2M simplex to pass the time which made the trip less boring. Before we knew it, we had stopped for fuel, a quick bite to eat and were now scouting out Mt Gawler…

Mt Gawler is just north of Adelaide, and is worth 2 points. It’s an easy access Summit and can be activated from public roadside land at a couple of places that are well within the activation zone.

Mt Gawler

We found a location where there was a small clearing not very far from the actual Summit itself to operate from, parked the cars and walked to set up the gear.

We decided to just use the one squid pole and share the activating with just the one antenna/rig combination…Larry mentiond that he had a new “experimental” antenna he was willing to try but doubted, and was also keen to give his newly acquired X1M qrp Rig another workout.

Larry's X1M QRP rig...

Larry’s X1M QRP rig…

We strung up the Larry’s doubtful endfed contraption with its mystery matchbox, plugged it in to the X1M and instantly found that  we weren’t hearing much…at all…not even band noise…after self spotting on SOTA watch, we put out a few calls but it became obvious that our signal was waaaaay down, as local VK5’s were barely copying and our best report was 3 x 1!!! The decision was made to change the antenna to a link Dipole, which Larry pulled out from his trusty antenna box. We quickly pulled down the original antenna and hoisted the replacement up in record time as we were keen to work some stations before and after UTC changeover…this was a vast improvement , and we began to make contacts, but signals were still down a bit. We then switched rigs to my FT817ND an i noticed an immediate increase in the background noise, whether this was because of increased sensitivity or just having louder audio, it was a lot easier for me to work stations, which had now had started to form a nice little pile up for both Larry and myself.

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Larry, VK5LY working the pileup on 40M…

Daytime conditions on 40M were not that flash, something I have noticed on 40M since the spring equinox at the beginning of this month. We switched to 30M briefly before packing up to head of for lunch, and self spotted on SOTA watch. Ed, VK2JI/P on VK2/HU-076 popped up with a very nice signal for a S2S…followed closely by Tony, VK3CAT with an equally strong signal. I feel 30M is the way to go heading in to summer for these morning activations, signals just seem that much better than 40 lately. Hopefully more activators and chasers will use this band.

VK5LA operating 30M...

VK5LA operating 30M…(VK5LY Photo)

All in all a successful activation, even though conditions weren’t all that great. I was a bit disappointed in the X1M QRP rig, It doesn’t have enough volume in its recovered audio for me to be even remotely interested in purchasing one. As a wearer of hearing aids, I need my audio to be LOUD! The display, although bright enough in daylight to read, was too small for my liking. It also seemed a little “deaf” on RX, like me!!! Larry mentioned that there was no AGC action in the radio either. They are considerably cheaper than an FT817 though, and would be a consideration for those looking for a SOTA capable rig on a budget…

Larry and I packed up afterwards and headed into Gawler for the 1 year VK5 SOTA anniversary lunch at the Kingsford Hotel. This was extremely enjoyable, and I was able to catch up with some of our other VK5 SOTA tragics, including Paul VK5PAS, Ian VK5CZ, John VK5BJE, Keith VK5OQ, and Andy VK5AKH and others, where we all enjoyed a few beers/wines and some fabulous food. Various bits and pieces of radio gear were pulled out of a variety of bags for show and tell, which capped off the afternoon nicely!

See you on a summit!

Andy – VK5LA

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Putting together a link dipole for SOTA…

Here is my take on the Linked Dipole antenna which has proven popular for SOTA work…

For some upcoming activations, I needed to put together a linked 20-30-40 M dipole as an alternative antenna to the EFHW I had built for my first activation on Mt Lofty.

While thes antennas work well, I felt that those using a linked dipole were putting out a slightly better signal, hence my interest…

Thes linked dipole antennas are available to buy if that’s your thing but I much prefer to make my own…I have been hoarding stuff in my “Junk Box” for years so I had just about everything I needed, except the centre support. For this, I decided to cut one out of some scrap plastic I had kept. This plastic is thin, about 2mm thick but quite stiff, although it has a nice flex if put under stress. I came from a promotional “point of sale” tray that fitted under a printer from my work place. I have dozens of the bloody things! It proved easy to cut with a good pair of sharp scissors, and was easily shaped with my leatherman tool knife blade. Conveniently, it had a nice lip bent over past 90 degrees, perfect for mounting the BNC connector…

Dipole centre cut from scrap plastic with BNC connector and Balun mounted.

Dipole centre cut from scrap plastic with BNC connector and Balun mounted.

Although perhaps not really necessary at QRP levels, I decided to fit a choke balun at the feed point to keep any rf from flowing on the outside of the coax. I used a Jaycar CAT. No. L-1238 Toroid as I had some on hand, and wound about 8 turns of some excess RG-316 and soldered one end to the BNC connector while the other ends of the coax were crimped to each dipole wire…

Centre insulator on the Squid pole ready to raise up

Centre insulator on the Squid pole ready to raise up

For the dipole links I used automotive spade lugs, as I had some on hand…other ideas would be power pole type connectors or even bullet style connectors, whatever you think is a fair thing! I crimp mine, and use Aluminox paste in the joint to provide longevity. The insulators are actually from the packaging holding my youngest lads last Nerf Gun firmly to the cardboard! I live by the motto, “never throw anything out!” – here it came in handy…

Dipole Link, I used automotive spade lugs and the insulators are left over bits of plastic from Xmas toy packaging!

Dipole Link, I used automotive spade lugs and the insulators are left over bits of plastic from Xmas toy packaging!

I have mounted a bit of PVC pipe in the front yard so that I can slip my 9M Squid pole over it and quickly raise it for operating or testing out a new antenna. I used this to gear effect today, and starting on 20m, I was able to trim the dipole lengths and add the next sections in a relatively short time. I was also very fussy with the tuning, and trimmed each band to 1:1.2 or better. This lets the FT-817 develop full power into the antenna on each band – important when operating at 5watts QRP, every milliwatt counts!

Testing the link Dipole

Testing the link Dipole

I got to try out the linked Dipole during my latest Sota activation, and it seemed to worked well on the 3 bands it was designed for. Due to the very strong winds I was only able to get around 70 degrees of angle between each leg, where as I like 100 degrees or better as I believe there is some cancellation of the TX signal below this angle…

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Squid pole bending in the wind…

Success!

So there you have it, much more satifying than buying a ready made unit, cheaper as well, I think I’ll probably end up keeping the EFHW in the kit as its only one piece of wire, and I bet that it would be relatively straight forward to make a linked version of one of those as well.

Thats the beauty of this hobbly, you can experiment at will and build stuff to your heart’s content, or if your time poor then there are usually plenty of companies the affer what you want and are very willing to take your money!

See you on a summit!