Building a Tuning Knob for SDR#

If you love using SDR’s on the PC but miss the old feeling of tuning the frequency with a knob then 19max63 has a solution for you. On his blog he’s posted about how he built his own tuning knob by using a USB mouse PCB circuit and replacing the mouse wheel with a rotary encoder with no detents. Detents are the little clicks or steps that you can feel in some knobs, but for accurate frequency tuning you don’t want those.

His post shows the exact parts he bought (knob, mouse, buttons), the mods he made to the knob and mouse PCB, and how he put it all together. He writes that parts can all be found cheaply on eBay or Aliexpress and the total cost to produce a single knob was only about $4 (though he had to buy some parts in lots of 5 to 10).

The finished tuning kob for RTL-SDR and SDR#.
The finished tuning kob for RTL-SDR and SDR#.
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I tried this one, works fine


Ha, when I was a kid in the 60s-70s I used to think; ‘with continued miniaturization, one day radios will just be a knob’.


And then I started in the 80’s and made the Nob a reality lol


I did this with a wireless mouse and it worked great for a while. But if you left it alone for longer than 10-15 minutes or so you had to reset the connection. Weird. But anyway, with the wired approach you don’t have to deal with that issue.

@19max63 Nice work. Find you a weighted VFO knob from a dead HF rig for the tuning knob, feels much more natural when tuning.


VFO knob for $$? I have reached a good compromise for free.
I have also installed a software to have two indipendent cursors.
See the updates


Heb jij deze ook gemaakt of een ander model.
Ik kom er niet uit met de foto’s op de site.
Potmeter aansluiten kom ik niet uit, en elke usb muis is anders wat betreft de print.

Heb jij meer info/foto’s van de bouw?

Groeten Sjaak.