The evening began with a YouTube video by Randy, K7AGE who gave part one of his introduction to Arduino.
Martin then followed with an explanation of what he wanted to achieve and how he went about it.
On display was a large Mag-loop aerial and it was pointed out that tuning by hand wasn’t an option, not only because it’s not healthy to be near a transmitting loop, but that the tuning changes when the operator moves away from the aerial. Martin produced an ordinary TV remote handset and explained how he used the Arduino to decode the output from each button. That output was then used by the Arduino to control a stepper motor which turned the tuning capacitor and thereby achieved a degree of remote control. Martin explained the programming needed to achieve this outcome. However, he felt the tuning didn’t have the feedback necessary for fine tuning as he listened to the background noise rising and falling on his rig. He did admit to have previously tried using a servo to turn the tuning capacitor and felt that offered a better feel to achieve resonance since using a knob for tuning in place of the TV remote offered better feedback.
Martin felt that both methods had led to considerable scope for experimentation in mechanical and computer science.