Voice Activated Relay

The VAR1 is a relay device that monitors audio activity over a wide range of input voltages and operates two sets of C-Form relay contacts in response to detected activity. The VAR1 can be used to detect voltages as low as signals directly from a microphone or as high as signals from 70V speaker systems. A low-level output of the detected audio, transformer-isolated from the input, is also made available for use with other equipment. The VAR1 can also be used as a balanced, low-impedance microphone pre-amp. The VAR1 is ideally suited to provide a set of contact closures for paging ports of lower cost telephone systems that do not have a set of AUX contacts to trigger paging equipment. An adjustable release delay (up to 25 seconds) keeps the paging system from dropping out in the middle of a page.