I have a homemade desktop swing, with a small permanent magnet on the swing. I want to keep it swinging when pulsed by a hidden electromagnet circuit underneath, so it keeps moving with no apparent help. The swing pulse needed is about 1Hz, which I need to adjust slightly to fit with the natural resonance. I have seen some ideas about an electromagnetic clock pendulum, but don't need this sort of accuracy. The power supply would be an AA cell (or two). Has anyone made something similar or know of a simple circuit?