A-135-4A/B VC Performance Mixer

Series A-135-4 contains several modules which are used to built a voltage controlled performance mixer. The modules of the A-135-4 series can be combined with the (non voltage controlled) mixer modules A-138o/p.A-135-4 modules in detail:A-135-4AA-135-4A is the main module. It is very similar to module A-138p, but with voltage control for all parameters (except gain). Also the front panels of A-135-4A and A-138p are very similar. The only difference are the additional LEDs which are used to display the magnitudes of all voltage controlled parameters. This is necessary because the positions of the manual controls do not necessarily correspond to the resulting parameter value because these are composed by both the manual controls and the applied external control voltages. Without the LEDs one one be left in the dark in regard to the actual parameter value.A-135-4A contains four voltage controlled amplifers (VCA) for each channel: one for the main level, two for panorama left/right and one