antenna ⁽⁵⁾

We held a MONSTER shed workshop to construct flowerpot antennas on Sunday 18 June at The Collective Community Hub, 1/33 Johnsonville Rd, . Around 30 people turned out and 22 antennas were built. The event commence dat 1.30pm with an introduction to the build by Bruce ZL2ABC. Teams of 4 to 5 people worked through a number of "stations" in building their antennas. We needed to be out of the building by 4pm, which was rather tight! A special thanks to Bruce's XYL who provided scones and personal service at the tea/coffee zone. This was a special shed workshop for any amateur (or prospective amateur operator) interested in building their own Flowerpot Antenna (see https://vk2zoi.com/articles/dual-band-half-wave-flower-pot/).   Members of other Wellington region clubs were welcome to participate in this activity! The cost of the antenna was $20.

Controlling field equipment under an ecosystem approach The June Shed Workshop was held a week later than usual - from 1pm to 3pm on Sunday 13 June 2021 at Mike ZL1AXG's QTH due to Queen's Birthday weekend getting in the way. Mike ZL1AXG and Bernard ZL2BD gave an introduction to the concept of an antenna ecosystem, in which a range of antennas could be controlled by a single microprocessor control system. This includes remote antenna switches (with just one antenna cable into the shack), 4 square switching, directional switching of beverage antennas or similar, tuning of magnetic loop antennas, and rotator control for beam antennas. Mike ZL1AXG also introduced Charlie Morris' Simple Transceiver for 80m SSB. He showed off some of the modules that are under construction, and outlined in a block diagram the design of the transceiver. He demonstrated how the audio modules could be tested using a multi-meter, signal generator and oscilloscope by inputing a signal from the signal generator at 1KHz in the front end of an amplifier and measuring the voltage on the oscilloscope or multimeter at the output end.

End-fed 1/2 wave At the July meeting (Wednesday 20 July 2016) members Frank ZL2TTS and Doug ZL2AOV gave brief 15 minute talks about their favourite wire antennas. Frank told us about his 40m and up dipole (20m long) fed by open wire feeders. He showed how the feeders were routed between the antenna and the shack, and material used for separating the wires and anchor points. Doug talked about his all band (80m and above) end-fed antenna (40m in length) fed by a balun and coax (with a good earth connection at the feed point). The talks provided for some useful thinking about alternative antennas at city sites where installation of a collection of antennas - one for each band is simply not feasible. These ideas (open wire feeders and end-fed antennas) provide a means of avoiding the problems of lossy small diameter traps or large diameter traps that tend to come to grief in Wellington winds. We can all bemoan the lack of sunspots ... but nothing beats a better antenna in getting a contact!

by Mike ZL1AXG A four square antenna has now been built and assembled, assisted by a number of local amateurs (Doug ZL2AOV is photographer, Bernard ZL2BD, James ZL2ET, flatmate Josh, and Malcolm ZL2UDF and myself are in assembly mode). Full testing wasn't possible because 20m at the test location in Grenada Village was full of local QRN at S6+ and peaking over S9. It did, however, pull in stations on 15m, even if it was not designed for that band! The team are busy assembling the portable four square array for 20m. The array takes about an hour to assemble: four antennas, four feedlines, a control box, coax and an ethernet line back to the rig and remote control, and 32 radials! Bernard ZL2BD measuring the impedance at the feedpoint with his antenna analyser. Note that we found in this first test that the initial feed arrangement wasn't satisfactory, creating too much coupling to ground. Doug reworked the "feet" giving them nice painted toenails (in British racing green). I started this project with the intention of engendering interest in phased vertical arrays. I imagine that the club will get to play with this antenna (and hopefully others like it) in our annual efforts in Oceania DX Contest and CQ WW contests. 20m was…

As I mentioned at our last club meeting, I have been working on a paper that argues for a reconsideration of DX and contesting antennas for the low bands. This means that a smaller site would be required for any replacement station for Quartz Hill. I argue in the paper that phased vertical arrays make the most sense for 160m through 30m for a NZ DX location. Any site larger than about 1Ha would be adequate to build a collection of such arrays. You can download the paper on the ZL6QH website. Mike ZL1AXG