AuxKey Pre-Mixer/Keyer
The Aux/Mix Pre setting pre-times the Aux bus output so that it can be re-entered back into the switcher from an external loop and be properly timed for selection on another bus. An AuxKey can only be re-entered this way once, attempting to re-enter an AuxKey onto another AuxKey that is being re-entered onto another bus will result in timing errors in the output.
The AuxKey is re-entered into the switcher by physically connecting cables from the output BNCs of the AuxKey to input BNCs on the switcher. These sources can then be selected on any bus on the switcher as an input.