Peter Larsen wrote in
:

I heard a Clash song the other day, and it was obvious that they got
an effect by putting the machine into record while recording an
oscillator. It had that "wowing up" effect. The Police did the same
thing.

You get the "moving up" effect by stopping the machine that records,
not by starting it. Think!

Or by starting a machine into Play with a pre-recorded constant tone.