Helitaks working on blacking out after a bushfire about 500m from home 18 February 2014.

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First Portable (ish) HF Antenna

I have always been a sucker for the sound and nature of HF radio. The hollow, distant and sometimes ethereal voices always seemed to be travelling a very long way. More so on a hot summers night somewhere in the outback.

This probably stemmed from the long trips to the country that I was taken on with Mum and Dad, be it holidays to visit relations in the Wheatbelt, the long trips to Port Hedland or the odd sojourn prospecting, the old AM broadcast radio was always on ABC, always there along with the static crashes of some distant thunderstorm.

Later, it was 27MHz SSB, Radio Club at school with a regular sched on 80m, listening to marine HF (Perth Radio VIP back then) and their scheduled callbacks to maritime vessels.

Constructing my first HF dipole and listening to 40m (albeit on a tapped whip), I was struck by the same sense of open distance that I had as a kid. It was then that I decided to make a concerted effort to complete the dipole in time for a trip to visit my parents in Kalbarri, 6 hours north of Perth, and attempt some contacts. Maybe listen to the Sunday morning broadcast and participate in the callbacks.

I have been extremely lucky to have an old friend (and fellow hoarder) that has been an Amateur Radio Operator since the mid-1980’s. This has meant that radios, technical expertise and random parts have been very readily available. A new Operator couldn’t ask for more!

Out of his overflowing shack, some wire was located, along with the phrase’ “.. here is some stuff I picked up at a Hamfest a few years back ..”.
This is a code I have come to recognise as, “I have had this stuff for a while, used some and saved the rest, which has followed me and the YL across the Nullabor a couple of times. It is really good and I can’t bear the thought of parting with it except for serious use”. In this case it is old Defense standard communications wire; strands of tinned copper and stainless steel encased in a very tough dielectric. Some may say ‘bomb proof’.

So, the elements were ready, just need to create a feedpoint. A quick visit to the J store down the road and I was the pround owner of a couple of opaque Jiffy boxes (I only remembered them coming in black with an aluminium lid) and some miscellaneous connectors, adapters and other hardware. I already had a small toroid from when said friend was instructing me in balun construction whilst preparing for my license. It was time to make one for real. Following the instructions in the Foundation License Handbook (as good a place to start as any) I set to work. Cross check all my connections, shove it all into the Jiffy box, add a SO-239 panel socket to the end and that’s it!

Testing came in the form of elevating the feed point as high as possible and stretching the elements out along the pencil pines at the front of the house. The top of a 3.5m length of conduit was about as far up as I could get the feed … and no match. The antenna wouldn’t tune on the cut length of 40m. Oh well, I’ll take it with me and see if I can do anything with it once I get up north. Too late to do anything else with it now.

Arrived in Kalbarri and the first couple of days were filled with fixing stuff Dad had broken or couldn’t remember how to use; computer (remove search bars from browser), aircon (clean filters), TV (retune) … etc and the obligatory sitting on the beach each afternoon drinking beer and pretending to fish.

Dad fishing at Red Bluff

Then the temperature came up a bit and most of the family were confined to airconditioned quarters after midday, for the next 5 days, as the maxima wandered past 43°C. Ideal time for playing radios.

Dig out the supposedly non-functioning dipole again and have another go. Elevate feedpoint by chucking a rope over one of the tallest branches of an olive tree out the front, pull the radials out and tether the ends to a couple of anchors (okay, trees), tune and … a match on 40m. Not sure what was wrong previously but there it was and a tuned match on a harmonic for 10m as well!

The next test was a live QSO. CQ’s in the late afternoon yielded no joy. Only few QSO’s in english could be heard from various parts of VK and many from overseas parts. Tried listening for SOTA activators whenever the Goat bleated at me, also to no avail. The next best thing? Send an SMS to old friend in Perth and get him to pick a frequency not completely laden with QRM at his end.

Despite evidence from others, I never thought that I would make 10W go so far! I was so surprised and excited when I heard the call on 7150kHz that I nearly forgot to announce our callsigns.

I did end up listening to the 40m news broadcast on Sunday morning and participated in the callback, albeit from the beach carpark on the tapped whip. Signal reports were well down on the dipole.

Signal reports on a QSO later that Sunday on the dipole were 3/7 to VK6AXB in a southern suburb of Perth, 5/9 to VK6JES in Geraldton, 90 minutes south of my QTH, and barely readable to VK6AEK/p in Albany (a squidge over 900km as the crow flies) on the south coast of WA. The low noise floor meant I had good copies on all stations.
I have no S meter so I guesstimated VK6AXB at 4/8 (100W PEP/5m AGL/dipole end-on), VK6JES 5/9 and VK6AEK/p at 3/6 ish. Once I had started a QSO with VK6AXB, VK6JES and VK6AEK/p piped up as they were cruising the band. I must remember to be patient and call CQ longer next time.

A successful outing, in the end, and a proof-of-concept for future portable operation with a view to the opening of SOTA in VK6.

Heaps of thanks to VK6AXB for all his assistance and VK6JES & VK6AEK for the contacts.

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Posted in Amateur Radio Stuff, Out & About

First Amateur Antenna

I remember, a long time ago, getting a CBRS license and building a ¼ wave groundplane vertical from aluminium tube & fencing wire for 27MHz.

Whilst browsing the ‘net for a suitable 2m antenna for home, I came upon a design that was similar in most respects to the one I had constructed years ago. It was originally designed to be hidden in a loft or suspended from a tree in a portable situation.

Mounting a device that looks like half a dying spider lurking on the roofline is not a ideal method of creating domestic or neighbourly harmony. With this in mind, I decided to utilise an old 2G mobile antenna that had been taking up space in the garage and removed the guts within. The remaining radome props up the radiating element which is the centre conductor of a length of RG58. The groundplane elements are standard iron wire of the co-tanger variety. Tuning was done mainly whilst the antenna was mounted on a 4m length of conduit; easy to raise & lower.

The next issue was to find a suitable mounting location, once again considering the previously mentioned harmoniousness. Listening to the WIA news one Sunday morning, I was reminded of the termination of VHF television services across Australia. Sure enough, the TV antenna on the roof was dual-band. If I removed the surplus elements, there would be enough space to bolt the thing onto the back end of the central boom. The mass of the device would be enough to counterbalance the remaining UHF elements on the other end of the boom.

Cabling is some surplus RG8 through the roofspace with flexible RG58 feeders at each end.

The only other considerations would be the effect of VHF RF output on TV reception and the very low power transmissions from the wireless weather station on the same mast. At this stage it appears that the weather station and TV reception do not suffer from the 5W output from a handheld. A full 10 watts would probably be another story entirely.

Fun and games with an HF dipole of some description can now ensue, now that I am intimately familiar with our residential rooftop.

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Posted in Amateur Radio Stuff

Licensed

Well, it’s only taken 30 years but I’m now a licensed amateur radio operator. It started at high school in the mid 80’s and, as most mature age foundation ops will testify, life got in the way.

Learning new things about antennas now. Ones that radiate.

Posted in Amateur Radio Stuff

AOCP(F) Has Arrived

Certificate arrived in the mail on Monday. ACMA application done and sent. Not long to go now. Travelling at the speed of Federal Government and my own organisational skills.

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No Idea

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First Post

This will, eventually, be a log of SoTA activations once the VK6 summits have been identified and published.

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