[sdiy] voltage-controlled AM radio tuning

[Cary Roberts]

>But if you are happy with a slower response, the coolest thing would be a
>voltage controlled motor doing the tuning. Using a small motor driving a
pot
>and the tuning shaft, and using the pot as a position sensor for a feedback
>controlled positioning circuit, you could wannder back and foward at will
>using CV.

That's actually a pretty good idea.  Servos are PWM controlled.  50hz with a
pulse width of .5ms to 2.5ms (1% to 5%) for most servos.  This would be
pretty easy to implement with a 555 timer and comparator.

-Cary