Tell us about yourself!
@spark light is just plain wrong when he says the actual peak only goes to half of 170V! The calculations above convert AC to Peak, not AC to Peak-to-Peak, so 120 VRMS * SQRT(2) = 169.7 V PEAK, approximately 170 V Peak for one half of a sine wave cycle. The other half cycle will have the same magnitude of 170V Peak, but in the opposite direction. Therefore, the peak-to-peak voltage is 170 * 2 = 340 V Peak-to-Peak.