Reprogramming a €15 USB Audio Dial to work as an SDR VFO Knob

Thank you to Tysonpower (aka Manuel DO5TY) for submitting information about how he's managed to convert a cheap €14.33 USB audio control dial into a VFO tuning knob for use in SDR programs like SDR-Console V3. He writes:

I sometimes miss a VFO Knob while using my SDRs, especially with SSB Signals or CW where you need to adjust the Frequency very fine.

Because of that I got myself an Audio Dial with USB, reverse engineered it somewhat and wrote a new Firmware for the STM32 used in the USB Dial.

It all worked out and it now simulates a mouse wheel with three different scroll speeds. There is also a Mute Function when you long press the Button.

I had a lot of fun during this project, even when it was a lot of time just for a VFO Knob :)

Manuel's blog post goes into deeper detail on how he reverse engineered the knob and how he re-programmed the STM32 microprocessor. He also includes the HEX file if you want to purchase the same unit and reflash it. His video below shows the modified knob in action.

[EN subs] VFO Knopf für SDRs aus einem Lautstärkeregler

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Ken C

i like this idea, i been thinking of buying or building something similar, i miss my icom HF rig with that big balanced & weighted VFO knob that i could either give a hard spin and slide across the band like a speeding freight train, or gently fine tune ssb to laser accuracy, i do like the SDRs too with the spectrum & waterfall display which makes point & click tuning on any signal that pops up really great, maybe somebody will come up with a USB VFO knob for laptops & desktops and sell them on amazon or the big online ham shops like HRO & Universal Radio