June Shed Workshop – Tips and tricks for the iCOM IC7300

A number of members have the iCOM IC7300 transceiver as their primary base transceiver. One member has an iCOM IC705 which has a similar user interface.

This workshop provides an opportunity for members to share their tips and tricks in using the IC7300. Even if you don’t have this rig, you should find it interesting how iCOM have developed their user interface. While it is straight forward to use, there are a number of traps that people discover as they go along. For example, if you have been using the rig on 10m FM (or similar) you may have adjusted the squelch control (which is shared with the RF volume control). When you switch back to 7.055 MHz for the Branch 50 NZART net on Sunday, you may find you can’t hear anything. Not even any band noise. You panic! What has gone wrong with my $2000 appliance? The answer is simple, always check the RF gain setting if you can’t hear anything.

Presenters will include Malcolm ZL2UDF, John ZL2XJ, Bernard ZL2BD, and Mike ZL1AXG.

We will be covering a range of topics including, pre-operating checks, simple controls (Gain controls, band switching, changing frequency on the waterfall display, using the attenuators and pre-amps, etc)

We will also delve a bit deeper into less frequently used features, including interfacing the rig to a computer, how to use the accessory outputs (e.g. to provide band-switching on a linear amplifier) and how to build a small interface to switch between pre-recorded voice messages for contest calling, recording the rig’s settings on the SD-Card, recording audio to the SD-Card, and further details on the various display modes (e.g. seeing RX and TX audio spectrum graphs on the display.

The shed meeting will be at John ZL2XJ’s QTH (9 Ridley Green, Churton Park) from 1pm on Sunday 5 June (yes that is Queen’s Birthday weekend). The meeting will finish by 3pm with tea, coffee and biscuits.


Shed Workshop on 6 March: The ZC1 test jig & a replacement vibrator

For anybody who has been around in amateur radio for a while, the ZC1 will be well known. It was developed by Collier and Beale during WW2 for use by the NZ armed forces. As it covered both 80m and 40m, it was highly prized by hams, in an era when commercially made equipment was hard to come by.

On Sunday 6 March 2022 Bernard ZL2BD gave a talk (on Zoom) on a ZCI test jig that he built, and has used to test the working of several ZC1s. The club owns a ZC1 that is for sale to any member interested in purchasing it and was tested using this test jig.

Bernard also demonstrated a replacement vibrator that doesn’t require modification of the ZC1 power supply. He is still working on variants to perfect this.

11 members and visitors joined in on the Zoom session, which was very well received by those attending.

Planning meeting and ZL2 Counsellor visit – 22 February

Our first regular meeting of 2022 was to have taken place on Tuesday 22 February at The Collective Hub, 1/33 Johnsonville Road, Johnsonville.

Given the Omicron outbreak it has been decided to cancel this meeting.

Richard ZL2FY, one of our Central Region counsellors was to have attended. Richard will be invited to attend a meeting later in the year.

Future meetings in March and April will shift to Zoom online meetings.

First Shed Workshop of 2022 – Xtal Filters

The Nano-VNA is a powerful tool for assessing the characteristics of all types of filters, including crystal bandpass filters. 

At the first shed workshop of 2022, Mike ZL1AXG discussed the construction of multiple crystal filters for HF rigs. This included a 12 MHz crystal filter for the Simple SSB 80m rig he is constructing in modular form (and this reflected the fifth presentation on that transceiver construction).

He also revealed a further 12 MHz filter and 2 filters at 4MHz for other  planned construction projects. In this workshop, Mike covered crystal selection, design options (including lattice filters in general and Cohn and QER filters) and the challenges of achieving a nice shape and a passband that doesn’t have too much ripple. 

He also demonstrated a “universal jig” for use with the nano-VNA and discussed when things go wrong with filters (in this case an LPF, or rather the test set up).