In prep – psp
At the LRS meeting on 29th October Bernie McIntosh GM4WZG talked about how the microcontroller, being a single chip with all the power of a computer, has become an indispensable component of virtually all commercial powered amateur radio equipment. He demonstrated a number of items of his own homebrew equipment and showed how anyone can use these ubiquitous devices in their own projects.
The Raspberry Pi etc are NOT microcontrollers.
Bernie wanted to use a very compact magnetic loop antenna which is capable of very similar performance to an 88ft doublet, at least on the higher HF bands. He was concerned about the continual need to re-tune it due to its narrow bandwidth, and so he designed and built a microcontroller unit to do this automatically.
Outline of the system – microcontroller controlling a stepper-motor-driven variable capacitor according to the frequency set on the transceiver.
Variable capacitor and stepper motor.
Microprocessor box with frequency display.
Interior of one version of the microcontroller box.
Another version.
Another application – microcontroller frequency synthesiser.
Block schematic of frequency synthesiser.
Choice of microcontroller chips.
The Atmel AVR.
The very much more powerful Atmel Mega 2560
The rival Arduino – Mega 2560.
The cute little Arduino – Nano
Other microcontrollers in the Arduino family.
(Makes a change from “That’s All, Folks”!)
After his talk, Bernie demonstrated his various microcontroller projects.
Bernie’s talk generated a lot of interest with a number of people planning projects of their own.
This was enhanced by Bernie distributing small microcontroller kits.
Brian – “Melvyn, I’m sure you need to get your eyes tested”.