QRP at Bamarang

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)
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 ki6mwn@yahoo.com. 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.
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.

IK1ZYW Labs & FT817 remote

Interesting update on IK1ZYW Labs on project to achieve remote control of the FT817. Also a pointer to an interesting page on FT817 Accessories, the external keypad project (circuit, manual & firmware available as well as various configurations of components including reprogrammed and tested chip ATtiny2313-20PU, xtal and 4×4 keypad) and the remote display project (pages under construction).

From the external keyboard info:

“…are you tired of hunting needed functions through F+Sel+A/B/C combinations? Do you want to improve your on-the-air proficiency? You can’t help but always press more keys at a time? Or always retouch the frequency when pushing the F button? An external keypad will let you re-discover the joy of QRPing with the FT-817(ND).

The IK1ZYW Keypad for FT-817(ND) is a wired partial remote control for the little Yaesu transceiver. It was conceived during a 6-hour field session at 2700 m.a.s.l. for a VHF contest in August 2008…”

Arnie Coro and the Super Islander

Looking back over some older email list posts today I came across an interesting exchange of posts on the QRPp list.

In early August Arnie Coro CO2KK announced latest progress on the ‘Super Islander Version 5 QRP transceiver project’. Key design criteria include using “as much as possible parts that could be recycled from easy to find sources of electronic components” such as toroids from PC boards salvaged from failed compact flourescent globes, and other treasures from broken VCRs, TVs and fax machines.

Via the short Wikipedia bio of Arnie Coro I discovered a link to more than seven years of transcripts of his weekly radio program ‘DXers UNnlimited’ broadcast by Radio Habana Cuba. Earlier transcripts are here. He also has a blog last updated in June. They’re practical and full of useful ideas.

One transcript is reproduced on dxzone.com and is an undated description of the project detailing what appears to be the first valve version of the project – I think designed by his friend Pedro, CO7PR. It brings home in a softly stated way the challenges and barriers facing radio enthusiasts in countries which for one reason or another don’t enjoy relatively high wages to afford factory made gear, and who have to be much more resourceful in making do with what they have available to get on the air.

A rude dismissive comment on the QRPp list prompted a firm but calm response from Arnie.

“Yes amigos, it is very easy for people having access to the money and the possibility of buying factory built radios or even well designed kits with full instructions and each and every part required… even washers , to just sign a check or complete and electronic transaction that will bring to  their homes a nice piece of equipment…

But that is not the case for many of us, that do enjoy very much the amateur radio hobby, and think not only about ourselves, but also about those that may benefit from also well designed, easy to assembly and to adjust radios that can be built using locally available parts.

Try to find even the lowest cost ceramic filter for building a single sideband rig in no less than 130 countries around the world and you will meet with the fact that they are impossible to locate, and the same goes for ferrite and powdered iron toroids, IF transformers, RF power transistors, small relays , RF connectors, resistors and capacitors, not to mention quartz crystals and integrated circuits !”

SolderSmoke named Arnie ‘Homebrew Hero’ earlier this year.

Arnie Coro CO2KK - photo by Rodger WQ9E c 2000
Arnie Coro CO2KK – photo by Rodger WQ9E c 2000

Arnie ended one of his missives to the QRPp list with this plea:

“Maybe one day the International Amateur Radio Union could sponsor a similar project to help promote amateur radio among young persons that live in poor nations where buying a factory made transceiver may be equal to the full salary of a worker during five years or more !!!”

I remember that one of the first QRP designs I ever built (back in the late 1970s) was a simple VXO controlled 6 W 20 m CW transceiver that appeared in QST (Dec 1978). It was later suggested as a prototype IARU transceiver as ham aid for developing nations. (This radio certainly worked for me, with a first contact into the US west coast with W6QR from a camp site in Kangaroo Valley!)

Arnie’s idea appears much more economical and self reliant, drawing on the potential of recyclable components. It’s also a design thought through from a Cuban perspective rather than a first world one.

You can even hear an interview with Arnie Coro recalling the Bay of Pigs invasion in 1961. [audio].

CW Operator’s QRP Club Inc

I rejoined the CW Operator’s QRP Club Inc. after a long absence. I was surprised to discover I’m entitled to my original membership no #56. It’s probably been almost two decades.
The Milliwatts per Kilometre award from the CW Operators QRP Club
The first Milliwatts per Kilometre Award from the CW Operators QRP Club
I have fond memories of the Lo-Key magazine, but I’m also keen to have a go at the club’s Milliwatts per Kilometre Award! 10,000km on 5W or 1,000km on 500mW!

K3WWP’s site

I’ve only just discovered K3WWP’s CW and QRP site via NW7US’ http://cw.hfradio.org/.

Amazed at the continuous record of publishing online since 1996 and the simple but powerful commitment to have at least one CW QRP QSO every day (a little like the necessary resolution of any half serious blogger!). What a model!

And what a wealth of good info there is online for the CW and QRP fan. Which makes the challenge of actually getting on the air and operating even greater!

Looking forward to exploring the K3WWP site further.