Great moment this afternoon when the Automatic Loop Controller fired up as it should. Happy days.

Automatic Loop Controller appears to be working as expected
The Automatic Loop Controller PCB and display

When I first fired it up, after loading up the Arduino program, all I could see was a dull green glow on the screen. It wasn’t until I remembered a comment from another builder about adjusting the potentiometer on the PCB that controls the LCD contrast.

It was a great relief that my slow and deliberate build – double checking all component values and joints – paid off. Next step is to build the SWR bridge and connect to the stepper motor on the loop.

4 Responses to “Success!”

  • Dave, WD8CIV:

    What kind of loop are you controlling?

  • Alden K6ZU:

    More information would be greatly appreciated. This is something that I’ve been considering and I would like to understand what your whole system consists of.

  • Stephen VK2RH:

    Hi Dave & Alden,
    Thanks for your comments and apologies for the mysterious post. I have been building a 4 foot diameter magnetic loop recently using a 200pF vacuum variable capacitor to tune 40m up to possibly 17m. You’re probably aware that magnetic loops have high Q and so can require frequent re-tuning as you move across a band.
    This post was about firing up my build of the automatic loop controller designed by Loftur Jónasson TF3LJ/VE2LJX. It’s comprehensively described at this page: It’s a solid design built around an arduino controller to manage the stepper motor dib=ving your capacitor. There’s also a Yahoo discussion group ‘loopController’ where Loftur is active dispensing advice.

  • Dave, WD8CIV:

    Thank you Stephen. I suspected you meant some sort of loop antenna.

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