The A-175 (Dual) Voltage Inverter simply does what the name says; it contains 2 separate inverters that invert the voltage of incoming signals; an input of +4 V will be output as -4 V, an input of -3 V will be output as +3 V, and so on.
Two LEDs give a visual indication of the (positive or negative) output signal for each inverter.
I use this module a lot, as i blogged before, most of the time both inverters are constantly attached to my A-174-1 Joystick module. I am thinking of buying another one soon, because this module is just so useful.
I love the fact that each inverter has 2 inputs, so they can be used as a (mini) multiplier. In this way you don't have to 'lose' the original signal.
As input source you can use almost any CV source, not just the ones that produce both positive and negative voltages.
A simple LFO will do, and the Joystick and Modulation Wheels are also very handy basic controllers.
The A-175 manual has some interesting user-examples, including a basic panning patch and a scale/arpeggio-mirroring patch, but again; possibilities are endless, the only limit is your imagination.