The 450 Series II is provided with a Normally Closed mic circuit, i.e., the GREEN wire is connected to the WHITE wire when the microphone switch button is Up. This provides a silent on/off when connected to a balanced input that does not have phantom power activated.
How can this be converted to a Normally Open circuit? I want to connect multiple 450 Series II units in parallel for a paging system in a large store.
Inside of the 450 Series II, locate where the WHITE wire, RED wire, and BLACK wire are soldered to the same switch terminal.
Remove the three wires from the switch terminal, solder the three wires together again, and insulate with electrical tape.
Removing the three wires from the switch terminal, but keeping the three wires electrically connected, provides the Normally Open circuit desired.