Ten members turned out to our Sunday 18 August meeting at Mike ZL1AXG’s QTH. To kick off the meeting we watched a Youtube video about the HAARP experimental ionospheric research centre in Alaska. Then each ember talked to their favourite amateur radio book.
Sunspots … Sunday 21 July 2019
At the Branch 50 event held at Mike ZL1AXG’s QTH on Sunday 21 July, Mike gave a presentation about sunspots – what they are and how sunspots impact on the ionosphere – and therefore on HF propagation, what the next cycle may hold, and their possible impacts on climate.
Sunspots Presentation Part A
Sunspots Presentation Part B
Shared lunch @ Mike ZL1AXG QTH
Branch 50 had its annual mid-Winter shared lunch on Sunday 23 June 2019 at Mike ZL1AXG’s QTH (2 Derry Hill, Churton Park, Wellington).
Plates of hot and cold food were shared alongside memories of Ralph ZL2AOH (now regrettably Silent Key as of Friday). There were also tales of the diminutive alternative to the Magnetic Loop, the Poynting Vector Antenna. When it was shared that the antenna was just 3/100 of a wavelength long, there was some disbelief about its properties. However, Bernard ZL2BD and Mike ZL1AXG noted that there seemed to be genuine research about this antenna, and given it is intended to receive magnetic waves (as opposed to electric waves) this may indeed improve reception. Also discussed were the challenges in making conical elements that are quite sizeable (albeit short).
There were also memory prompts from the past from members
- A device of unknown purpose (Magnetron?, Phaser?)
- A Creed latching relay (somewhat larger and heavier than you might think)
- tales of great DX as a schoolboy when visiting the local ham radio operator in Cornwall, and a special QSL card from a Penzance Pirate
- Two giveaways …
- A tale of a repair of a Japan Radio Company (JRC) transmitter
Shed Workshop and RemoteDX AGM – 26 May
We held the June Shed Workshop a week earlier than usual on 26 May 2019. The event was held at Bernard ZL2BD’s QTH at 1 Winsley Tce, Churton Park, Wellington. The topic was Class D Audio Amplifiers. These audio amplifiers come very cheaply as modules and are incredibly small and light weight when combined with a switched mode power supply. They can also be scaled for different power outputs by simply changing the supply voltage. They have many good points, but there is a downside from an amateur radio perspective … they can generate a large amount of RF noise!
Bernard gave an excellent overview of the concept, the application and demonstrated the range of commercial modules available. His paper will be available here shortly to read.
The shed workshop was followed by a special afternoon tea at 2.30pm and then the AGM of RemoteDX Inc at 3pm. It was an excellent afternoon, with gorgeous late autumn weather.