... Microphone and Speaker . The GSM Controller RTU5010 with 4 I/O ports, without AD inputs, Microphone and Speaker. The ... , power transmission system monitoring and other applications. RTU5011 I/O interface>>>>>GSM Controller RTU5010/RTU5011 suitable for: 1. ... GSM SMS Controller, GSM Home Automation system, Industrial Remote Controller, GPRS RTU Data Logger, GSM Telemetry, Temperature Measurement Logger, ...