The VAR1 Voice-Activated Relay is a DPDT relay device that is activated when an audio signal is detected at the microphone pre-amp or at 70V 25V or 600-ohm line level inputs. It has a number of useful applications such as muting a sound system in response to a microphone or telephone page activation of accessory (security) equipment or activation of a zone paging module. A slide switch is included to select the pre-amp or the line inputs. The VOX detect circuit also includes volume sensitivity and delay controls. The audio output is an isolated 600-ohm transformer.
The unit operates from a DC power source (not included).
Features: 2 sets of C-Form (N. O. & N. C. ) relay contacts respond to audio activity. 4 levels of input signals: microphone 600-ohm line 25V & 70V speaker systems. Built-in balanced low noise high gain microphone pre-amp. A transformer-isolated 600-ohm small signal level output of detected audio available. Trigger threshold adjustment.