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ETS SARM-1 Sound Activated Relay Module For SM1 Microphones & More
The ETS SARM-1 relay module can connect to any SM1 series microphone, and it has an audio loop through for connection to DVRs, interface equipment, etc. This item accepts line level inputs and it has a relay output for connection to DVRs and alarm systems.
Furthermore this device has an internal relay thatis activated for an adjustable amount of time upon detecting an audio level above an adjustable pre-qualified "threshold”.