Doepfer A-197 - Analog Meter

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"Colletors item - no longer available

This module serves to display DC or AC voltages by means of an illuminated moving coil meter with mirror scale. The display range is 0...+10V (resp. -5V...+5V in the offset mode). The module features 3 different measuring methods that are selected by a toggle switch:

✔ Full Wave Rectifier: This mode is normally used to display audio signals resp. AC voltages. The incoming signal is rectified and smoothed with a low pass filter. Even DC voltages can be measured in this mode. The display shows however the absolute value (i.e. positive voltages remain unchanged, negative voltages - e.g. -3V - are converted into the corresponding positive voltages - e.g. +3V). To distinguish between positive and negative input signals a LED is available that lights up in case of a negative signal.

✔ Direct Mode: In this mode the incoming voltage is lead to the meter without additional electronic modification. This mode is planned to display positive DC voltages, e.g. ADSR (A-140/141/A142), MIDI-to-CV (A-190/191), positive random voltages (A-149-1), foot controller (A-177), Gate/Clock signals.

✔ Offset Mode: In this mode +5V are added to incoming voltage before it reaches the meter. Zero volt input correspond to the middle position of the display needle (i.e. +5V read out). This mode can be used to display positive and negative voltages, e.g. a slowly swinging LFO (A-145/146/147), S&H (A-148), bipolar random voltages (A-118), joy stick (A-174), Theremin (A-178), light controlled CV source (A-179).
The measuring input is available as a triple multiple so that the signal to be measured can be used in the system simultaneously. A LED is used as an indicator for negative voltages."