A-143-4 Quad VCLFO / VCO
Module A-143-4 is a fourfold voltage controlled low frequency oscillator (LFO). As the frequency range includes moderate audio frequencies it can be used as a four-fold VCO too.
The module was planned mainly as a quad VCLFO. But we added a range switch (nothing but a switch for two different capacitors) so that even audio frequencies are possible and the module can be used as VCO with some restrictions too. Because of the closeness of the main circuitry (i.e. four VCO cores within less ~ 1 square millimeter) the oscillators may lock if the frequencies are very close to each other and the VCO frequencies interact marginally. If a high quality quad VCO is required the A-111-4 is recommended as this module has four separate VCO circuits available.
This document explains the functions of the 17 jumpers: A143_4_jumper.pdf
Technical details concerning the Reset and Direction function:
The reset of a triangle based LFO or VCO consists usually of two functions:
For unit #4 all types of sync are available: