AmateurRadio.com

Last weekend I had a great time playing radio. Along with half a dozen other families and all our kids we went to spend the Easter weekend at the “mud brick mansion” at Bamarang on the Shoalhaven River, a few km west of Nowra on the south coast of New South Wales. Courtesy of the pod on my car I was able to take quite a few radio bits and pieces along.

We enjoyed perfect autumn weather while it rained back home in Sydney!

I even managed to build the neat little EFHW (End Fed Half Wave) Tuner designed by Stu, KI6J on a shady verandah. The kit had arrived a few days earlier and I made sure I had everything I needed to build it away from my attic/shack/workshop. In fact the weekend became a sort of trial for field day and a great way to identify the essentials. If there’s a lot of gear on hand an awful amount of time can be wasted deciding which bits to use and how.

I was inspired by reports about the EFHW tuner and the appeal of not having to worry about ground radials. What clinched it for me was a photo I saw on one of the (far too many) qrp email groups I try to follow showing a ham on a mountain side beneath his arching squid pole with the little tuner matching the hi-Z of the half-wave antenna to the 50 ohms expectations of the tiny transceiver which was probably an ATS3b.

So that was my mission for the weekend.

The tuner kit went together in a very short time. Before accepting my order Stu, KI6J sent me a powerpoint of the assembly instructions so I was sure I could handle the construction. The fiddliest bit was the tiny binocular ferrite core transformer for the bridge. Fortunately he provided enough wire in the kit for me to botch it the first time round and do it perfectly the second!

After a couple of leisurely hours mostly taken up with drilling holes in a tiny plastic box it was working on the test lash-up. The polyvaricon is delightfully sharp. You tune by dimming the LED – and then switch out the bridge to transmit.

The KI6J EFHW Tuner kit almost complete with the 5k ohms test load in place. The builder provides the enclosure and connectors. (Photo sourced from instructions)

I had a 10m (almost 33 feet) squid pole (aka Jackite or crappie pole) with a tiny pulley from a boating store attached to the top with cable ties. I used the guy ropes from my Buddipole setup to hold the pole up straight. It stayed up all weekend.

The half wavelength formula in feet is 477/freq in MHz, or just on 68 feet (20.7m) for the code end of 40m. The far end of this was held up – via a plastic button insulator – by a fishing line launched up into a tree using a half-filled plastic drink bottle. All too easy! The near end of the antenna simply terminates in a banana plug that connects to the little tuner. I also connected a short 5-6 foot counterpoise, which was essential.

I had a great time playing with the tuner and my new SDR-Cube pumping out a whole watt of RF, as well as the trusty little FT-817.

Now I have a clear idea of what’s required for an effective little kit of gear to take up a hill for relatively speedy SOTA style deployment. And maybe I’ll fill the water bottle for those trips.

If you’re interested in getting hold of one of these nifty little EFHW Tuner kits you should contact Stu KI6J at [email protected]. US$27 included shipping across the Pacific Ocean! Fast and very fair!

My blissed-out second operator in the field at Bamarang, near Nowra NSW. He helped me retain my QRP calm.

During a trip into the township to replenish supplies I found a fishing tackle shop with an Easter sale on, and bought a couple of handy Plano tackle boxes and some inexpensive 10m lengths of nylon coated stainless steel ‘leader line’ wire which I’m sure can be used for a handy weatherproof dipole. As long I don’t have to solder the stuff.

A short while ago, Canonical released the latest version of Ubuntu:  the fabled Maverick Meerkat, 10.10. This is the latest in Ubuntu’s normal release cycle and is not LTS. I had occasion to upgrade a couple of my personal computers running Ubuntu to the wily Meerkat. Find out what’s new in 10.10, and what’s old, in the first segment of LHS #049.

After that, Richard and I tackle the WSPR protocol for ham radio again. When it was discussed the first time around, neither of us had much of an idea what it was or how it worked. Armed with a broader understanding and a lot more experience, we talk about what works and what doesn’t work with WSPR, how to get it up and running on your system and what we like and don’t like about it.

Following that it’s on to witty banter, a passel of badgers, some hijinks, censorship, feedback and more entertainment than you can shake a wet hedgehog at. Thanks for tuning in. We love you all.

73 de The LHS Guys