The PH-4 is a LFO module with four outputs that are offset in phase 90° each. Unlike normal quadrature LFOs it generates not only a sine waves but also triangles.
The internal LFO can generate a sine or a triangle wave, the selection is done with a small switch. The modulation generator's frequency can be set manually (40s-6ms cycle length) and has voltage control, too. Level-CV is used for simultaneous modulation of all outputs' levels, e.g. in order to fade the LFOs in and out. The voltage controlled offset function adds an offset voltage to all outputs i.e. they do not oscillate aorund 0V but above or below.
The eight LEDs indicate, rate, phase and waveform at once.
All Cwejman modules are screened against interferences, protected against reverse polarity and contain calibration options on the backside.