First off, a multi meter is calibrated for 50-60Hz. It will not report accurate measurements from the generator, especially if you are not able to account for the waveform in use, etc.
Second, the waveform used in the CS preset has 33 cycles embedded, with a sweeping increase in amplitude then a decrease.
When played at 5 cycles per second, the resulting frequency is actually 165 Hz. The sweeping amplitude is constantly modulating the amount of power being applied in 17 distinct steps.
Every 5 minutes, the current is reversed, to prevent buildup on the rods.
For more details, please check the link: