Maybe all they have is a hand-cranked generator.

I think Doc Carpenter here is right: they're using a hand-cranked generator.

Power was supplied by batteries and a hand-cranked generator.

There's also a hand-cranked generator, but its range is pretty limited.

For entertainment, they turned to hand-cranked generators to power radios and televisions.

There, the witnesses said, men and boys between the ages of 15 and 55 were beaten and given electric shocks with hand-cranked generators during interrogations.

This instrument required no battery, using instead a hand-cranked generator, but it was also based on a dial indicator.

The chain was then hooked to something that would deliver a charge, most likely a hand-cranked static generator.

They brought their own hand-cranked generators.

The power to ring phones was historically supplied by a hand-cranked generator on the customer's and operator's telephones.