Doepfer - A-145-4
Module A-145-4 is a simple quad LFO (Low Frequency Oscillator). Not a very "exciting" module, just a bread-and-butter device and a simple demon for work. Virtually in every modular system several LFOs are required for modulation purposes. The module contains four simple LFOs with the waveforms triangle and rectangle. A dual color LED (red = positive / yellow = negative output voltage) indicates the triangle output of each LFO. The frequency range can be chosen for each LFO individually by means of a jumper between about 50 Hz ... 0,04 Hz (about 25 seconds, jumper removed) and about 2Hz ... 0,002 Hz (about 8 minutes, jumper installed).
The module can be treated as a slimmed version of the quad LFO A-143-3 as it has similar features available. But the distances between the controls are smaller and rubberized small-sized knobs are used. In return the front panel has 4 HP only which is less than one third of the A-143-3. The module is primarily planned for applications where only limited space is available. The functional difference compared to the A-143-3 are the missing sawtooth outputs and frequency range switches.
If more advanced features are required (e.g. additional waveforms, complex waveforms, waveform reset, adjustable waveforms, voltage controlled frequency and level) the modules A-143-1, A-143-3, A-143-4, A-145-1, A-146 and A-147-2 are available.
The following document shows the positions and functions of the jumpers of the module: A145_4_jumpers.pdf