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ELK930
The ELK-930 performs three functions. It can detect ring activation from one or two doorbell buttons and a single telephone line. It conveniently isolates the voltage and current and produces a signal which can be used to trigger an automation controller, relay, timer, etc. The circuit board is pre-scored so that the individual detectors may be snapped off (separated) from each other.
Communications systems are an important part of your automated home – from full-service Home PBX systems with voicemail, to intercom systems, to video door phones, to doorbell and phone detectors.