At 4 hp, the Zlob Dual VCO is incredibly compact. The two oscillators have squre, triangle, and sine wave outputs, with control over tuning and an attenuator for CV V/O input. The module has a tuning range from .2 hz (one cycle every 5 seconds) to 18khz.
When a control voltage is inserted, the fine tune control becomes an attenuator for the incoming voltage. In exponential mode, when the attenuator is fully clockwise, the VCO will track around 5 volts per octave.