Had a play with my Mag Loop project, the problem I had was that the stepper motor which turned the Vacuum Capacitor introduced a lot of noise into reception, removing the supply from the stepper motor caused the bellows in the capacitor to return to a resting position, knocking the tuning out.

To combat this I have fitted a friction brake which uses a terry clip to the shaft of the motor, this seems to work ok, but a bit more work needs to be done.

The loop tuned perfectly on 3Mhz, pity it’s out of band, oh well, a job for another day!