Very often in amateur radio, it is possible relatively easily to construct equipment to add to the radio station which, if bought commercially would cost ten or more times the amount. On this page, you’ll find details of a few of the ancillary pieces of equipment I’ve developed for the station. None are complex, and the information is shared as a prompt to help others who may be considering a similar design, rather than a more expensive purchase of commercial equipment.
SteppIR transmit inhibit – inhibits the transceiver whilst the SteppIR is retuning. This is based on the N8LP design, with some simplification.
Band decoder – provides a relay driver for each band from Yaesu four-line band data. It is based on five antennas: 10-20m (5 bands), 30m, 40m, 80m, 160m although the internal wiring can be re-arranged for any other combination of antennas. I decided to use this approach rather than use control of antennas from the logging software, to allow maximum configurability on antenna selection.
Receive antenna isolator – protects the transceiver front-end when using receive antennas.
Basic SO2R controller – but needs computer with an LPT parallel port, which is increasingly difficult with more modern computers. This was my first SO2R controller – it worked well, but I have now adopted the Microham controller as it handles more functions. But as a basic controller (perhaps with a WinKey board in the same box) it offers a cheap and effective alternative.
“First one Wins” controller – a simple circuit to allow two transceivers to share a single amplifier and antenna system. Designed for multi-operator single band contests.
Rotator repeater – an easy way to overcome ohmic losses in rotator control cables when the rotator is a long distance from the control point
I have not provided any narrative with the above – simply the circuit diagram. This should be enough to explain the basis of the circuit. You can email me for more information:
No liability is accepted for the circuits and commentary given in these pages. All information is provided in good faith to be used only by those who have sufficient technical understanding to recognise and manage any risks involved