Branch 50/74 Lunch and Shed Workshop Event

On 1 March from 12 noon -3pm we met over a light lunch at Mike ZL1AXG’s QTH.

The Branch 50 NZART Committee ordered in a light finger-food lunch (savouries and sandwiches) as we were hosting Branch 74 for a combined branches event. Disappointingly, only two guests showed up … they were our guest speaker for the workshop, and one Branch 74 member! Mike noted that the year had not got off to a good start with few turning up for the combined branches BBQ organised by Kapiti Branch. It appears many amateurs simply don’t want to come out any more to events. However, complacency may well spell the end of amateur radio as we know it. Member attendances at most branches appear to be plummeting, even those that still have 100+ members on their books. Things are getting tougher for ham radio, with suburban QRM often sending the meter over s9 on the low bands, the sunspot cycle likely to be at its worst for some years, and Councils getting tougher in their district plans on amateur antennas (see the recent decision by Kapiti District Council).

It is likely that something radical will be required to breathe new life into our pastime. Maybe the new IC705? (just kidding!).

Putting aside the challenges for our hobby, our special guest presenter – Charlie Morris ZL2CTM – talked us through his approach to building homebrew transceivers. Charlie has built many working transceivers and uses them regularly, including on tramps into the bush.

Charlie Morris ZL2CTM talking about the two most important books needed by home constructors surrounded by a collection of homebrew txcvrs for 80m – 20m.

Charlie has a range of experimental radios using quite different techniques. They are mostly built inside Sistema lunch boxes, with full visibility of the “inner workings”. He has a global following of QRP and homebrew affiacondos who follow his latest creations. For example, check out his videos on Youtube and this review of an SDR design on Soldersmoke:

Some wonderful hints were dropped, including a suggested order for constructing modules in the transceiver, how to use veroboard (matrix board) by placing all the components on one side of the board (the side with the tracks on it), how to bond a module to the ground plane so as to reduce the chances of unwanted feedback. Charlie also made a suggestion on how to switch the IF strip between TX and RX so you don’t crossover inputs and outputs using relays (hint: switch the mixer frequencies on your PLL device).

Charlie’s well received session ended with tea and coffee and a lot of chat amongst members with most members leaving around 3.45 pm. Charlie received many compliments and he provided a lot of stimulation for members. Maybe some of us will be buying those design manuals and building our own transceivers? For the Chair, it presents a challenge to move away (at least in the first stage) from a focus on getting the enclosure looking good, to coming up with new solutions to old problems by using a breadboard approach. i.e. it is time to use the box of processors being built up and have a play with a few IF strips, etc. Now if only there was time to do so!

Combined branches BBQ – This Saturday (25 Jan)

The Wellington VHF Group and Kapiti Branch are having their annual summer BBQ on Saturday 25 January 2020 at QEII Park, Paekakariki from noon.
They are inviting all of the other branches in the Wellington Region to attend.

We will be at QEII park picnic area 7 – see the map here:  Entry is via Wellington Road, Paekakariki. (access from Paekakariki  and you will need to bring everything- even shade and a seat!). There is plenty of space and last year was a lovely afternoon.  If you can, bring a BBQ to cook on (gas only).

Kapiti branch are going to operate a hidden transmitter hunt as well.  All are welcome!

Branch 50 NZART at Maker Faire 2019

Branch 50 members, were present at the 2019 Maker Faire which took place at Queen’s Wharf in downtown Wellington on 20 October (10am – 4pm) . We participated in the NZART stand, along with members from branches 42 and 63. NZART brought amateur radio to the people. We gave away brochures about the branch, engaged with a wide range of people and talked about our hobby.

Note that there was no regular branch meeting in October, due to the Faire.

Phasing two antennas & TX/RX switching – Shed Workshop – 6 October 2019

Bernard ZL2BD gave a talk on how to safely switch between RX and TX antennas on your rig and demonstrated the circuit (which is probably not suitable for break-in keying). This circuit would allow us to use our active antenna  or mag loop antenna on RX and our standard antenna on TX. The MFJ unit above is an alternative approach.

He also demonstrated a simple phasing circuit that works with two RX antennas to reduce noise levels or to peak a signal.  Steering of a two antenna array throughout 360 degree is possible.   Two active antennas can be used, or in fact, any two antennas spaced less than 1/4 wavelength apart can be steered (on RX) to reduce unwanted noise and maximise forward gain.

The following articles relate to the workshop: