What exactly does a Proctavia do?

[ToneWeasel]

Hi. I fairly new to electronics and circuits.  Can anyone explain to me exactly what it is octave pedals do?  I know the wave is rectified so to speak, but it's not exactly a full wave rectifier either. I'm kind of confused on this. 

[PRR]

Do you know that an octave is 2:1?

If you are "new to electronics", rectifiers are hard to grasp.

Yes, it is a full-wave rectifier. (There are many ways to skin this cat.)

If you live in a 60Hz-power land, the prime hum in your amplifier is 120Hz from the FW rectifier powering your amplifier. The "octave-up" circuits do a similar thing with guitar-band tones.

[ToneWeasel]

I do know what an octave is.  I'm trying to figure out what this type of pedal does to a waveform.  I made a recording using a Proctavia.  I expected the waveform to be the absolute value of the clean waveform... but it's not.

[slacker]

I don't exactly what it does to the waveform but the signal is boosted and distorted before it's rectified so the output won't look like a rectified version of the input.