Periodicity
	The Buchla 281(e) quad function generators are the unsung heroes of the Buchla Electric Music Box. They perform all sorts of transient and cyclic duties. They are among my most-touched modules. That said, I still feel the need for some dedicated LFOs.

Global All the LFOs have the expected rate control and cv attenuator. There is also a global range switch to select between low and really low frequency ranges. LFO 1 section The symmetry control pushes the waveforms into asymmetrical shapes. The effect is different for the different outputs. The sync jack resets the cycle to the beginning. If frequensync is engaged, the cycle time of the LFO is slaved to the period of the pulses arriving at the sync jack. In this mode, the freq knob becomes a multiplier on the period of the sync jack. The freeze input stops the cycle in suspended animation. When the freeze signal goes away the LFO resumes as if nothing had happened. The LFO Stew output provides a numbers of different flavors of combinations of the LFOs. In addition to the normal outputs, there is also a strobe output. It can be set to an arbitrary point along the cycle time of the LFO. It is useful for syncing further processes, or triggering envelopes, or...

LFO 2 & 3 These are simpler LFOs that can be slaved to LFO1. When slaved, the frequency becomes a ratio to the LFO1 frequency. Each of these have one strobe output. I haven't quite decided whether or not the waveforms on LFO2 and LFO3 are affected by LFO1 symmetry, when slaved (I'm leaning against this). Or whether LFO 2 & 3 are frozen when LFO1 has freeze applied, for that mater (I'm leaning towards this one.)

Here's a picture of the waveforms during a sweep of the symmetry control. The green lines are the start of each cycle. In top to bottom order, the waves are sine, triangle, saw, square. Keep in mind that the symmetry control is being continuously swept, so that the waveforms only look like themselves when symmetry is close to zero, which happens somewhere around the fifth or sixth frame.


Here's a picture of the results of using the freeze input. First a normal cycle or so, then a cycle in which the waveform has been frozen in several places:


This is a picture that shows some Symmetry mod abuse. I have the Symmetry control almost all the way down, and I'm modulating Symmetry with a sine that is several times the frequency of the LFO.

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