20110712 - VK6 Portable Field Day

posted 25 Aug 2011, 18:24 by Onno Benschop
On the weekend of the 16th and 17th of July several amateurs from the Hills Amateur Radio Group (affectionately known as HARG) got together to hold the inaugural VK6 Portable Field Day on the shores of the Harvey Estuary, 20km south of Mandurah in Western Australia. Finding an excuse to camp with a radio was never going to be a problem, figuring out a date and what to bring proved to be much more challenging.

Having overcome the date selection, wedged in between several other events with fingers crossed for the weather because it takes a special kind of fool to camp in the middle of the winter – we managed to create an event worthy of the name – although, strictly speaking we only set up one radio and some antennas. It was loads of fun and we have a mind to make this a regular affair.

Figuring out what to bring turned out to involve bringing everything bar the kitchen sink – mind you there was a caravan from one amateur, so strictly speaking we did also bring that. Food wasn't a problem, bring what you need – so everyone brought more than they needed and we had more than enough to go around – twice.

As an aside, the weather coming up to the weekend was deteriorating rapidly, to the point that you had to slow down on the freeway to avoid having an accident. Turns out, that's as bad as it got. We had high humidity, but no rain during the day (some overnight) and while it could have been a wet and muddy affair, it was bracing, but not unpleasant.

On the equipment side there was spare wire, coax on rolls, soldering irons, verniers, pliers, connectors, crimpers and the like. The only thing I forgot was the little patch lead that goes between the front-panel of a Yaesu 857D and the radio – all I had was the 5m separation cable which appears to suffer from HF injection at some frequencies.

From a technical perspective, I have a Yaesu 857D transceiver connected to a dual-band Diamond SG-7200 antenna for 2m/70cm and an SGC SG-237 antenna tuner connected to a 12.49m piece of “random wire”, which is wound around my 12m Spiderbeam squid-pole. There are 16 radials, also 12.49m long which complete the antenna. We used this as our main set during the weekend.

As I said, as an event we had a blast. We were far enough from Perth to be out of reasonable range of the local repeater, VK6RAP, so we “invented” a way to stick my dual-band antenna on the top of the squid-pole – suffice to say that it looked like a dogs breakfast and by the time the aerial was in the air, the whip was horizontally polarised if you get my drift. For those not graphically inclined, the weight of the Diamond SG-7200 on the top of a 12m Spiderbeam causes the tip to bend to the point where it's horizontal.

Dropping the whip down several segments improved things a little, but HF was affected, so we ended up just using the contraption for about an hour while we participated in “F-troop” which runs from 8:00 to about 8:30 every Saturday on VK6RAP. In order to actually get to the repeater required more power (I suspect because our antenna was on a strange angle) which one of the advanced licensees confirmed by trial and error, balancing transmit power and battery drain.

Since I have an F-call, I cannot transmit with more than 10 Watts. However, as a second operator of a licensee with more privileges I can use their power settings, so for the duration I became a second operator, weird call sign, with a stroke 2 in it – much hilarity for newcomers who didn't recognise my voice and wondered why I knew everyone. A credit to Miles, VK6MAB who hosted F-troop on this day - we could really only participate from the side-lines.

One of our amateurs brought out his hand-built Slim-Jim antenna which needed some tweaking. Pulling out an antenna analyser revealed that it was tuned to 153MHz, so with a little help from a soldering iron we tweaked it to tune to 146MHz, making contacting the repeater actually possible from the location without the gaffer-tape antenna special we built previously (and with only 10 Watts).

On the HF front we participated in the Southern Cross DX net and the 7.130 DX net as well. We talked to some amateurs across the bands. Mostly we spent a lot of time around the campfire eating and talking. While we were talking and generally having a great time we did notice lots of HF noise, which was rather strange since we’d selected our camp location based on past visits when it was extremely quiet.

Turns out that generators are not the noisiest things around; by far the noisiest contraptions invented by man are inverters. It's like sitting at a radio with headphones on and having someone stick a knitting needle in your ear for several hours – not enough pressure to draw blood, just enough to give you a splitting headache. So we had a little chat with our fellow campers and educated them on the benefits of HF silence – turns out most campers were more than happy to turn off their stuff, since in many cases they didn't even realise it was on!

We took the opportunity to trial some other things as well. Tying the Spiderbeam to a tree-stump works, though you do get dizzy tying the rope. We used a marquee to set-up our “shack” and learned that it's a good idea to make sure all the bits – like walls – are in the bag before you bring it. Hooking up an external speaker to your camp radio makes the interaction much more sociable, since everyone can hear what's going on, rather than just the person on the radio. Making a packing list for your go-kit is a great idea, since it will help prevent missing little cables you might need.

We had a visit from some locals and one who kindly supplied lots of fire-wood (thanks Norm - you’re the best!) which made the experience all the more pleasurable, and being an hour from Perth, we had some day-trippers come by to sample the freshly made damper.

Amateurs on site included: John VK6FJON, Chrissie VK6XCJ, Allan VK6AN, Alan VK6PWD, Marty VK6FDX, Simon VK6FBMW and myself, Onno VK6FLAB. Jason, a potential amateur also came for a visit.

For our next camp out we'll see what other experiments we can come up with. We'll advertise the event around the traps and if you're available, feel free to join in – we're all just looking for an excuse to play with our kit.

Onno VK6FLAB is a recent F-call, hosts F-troop on VK6RAP every Saturday at 8:00am - you can find callbacks on the HARG website at harg.org.au. You may have heard his segment on the VK6 or WIA news, “What use is an F-call?”. He recently was elected President of the Hills Amateur Radio Group.