5 to 15 Hz square wave; adjustable voltage?

Hi guys

I know just enough about electronics to know how little I know, so am hoping for a lot of assistance with a circuit diagram plz.

I would like to build a power supply that can produce both pulsed DC and square wave AC at frequencies of around 5 to 15 Hz. Adjustable.

Voltage should also be adjustable from around 2 V to about 36.
Amperage is low, but the more the merrier!

I dont mind losing half the power for the DC pulse at this point.

Is this possible at a reasonable cost?

This is to experiment/produce colloidal/ionic silver.

Auditioning for the Blue Man Group?

Yep! Although I plan to stay away from Salts in the electrolyte.