Power and Power Management Powered by a commonly available 9-volt alkaline battery and internally regulated to 5 volts for consistent performance throughout the life of the battery. Keypad is using power only when transmitting and acknowledging an entered response. Low battery is indicated by the rapidly flashing seven-segment LED display when about 100 responses are remaining. Battery provides sufficient power for 10,000 response interrogations before requiring replacement. Each keypad has a unique address between 1 and 650.
Keypads operate independently of each other, and keypad addresses are user programmable.
Response entries are acknowledged when received by the Base Station. Integrated error checking ensures accurate communication of responses and control functions. Communications to and from the Base Station are crystal referenced. Transmitter operates on 433.92 MHz. Receiver is SAW referenced superheterodyne design with phase lock detection for superior sensitivity.