Published:2009/6/17 2:24:00 Author:May | From:SeekIC
The baby-alert transmitter is built around an LM334 quad op amp(U1), two LMC555CM CMOS oscillator/timers(U2 and U3), and a few support components. The transmitter sends a signal on receipt of a sound at MIC1. It has a frequency of around 125 kHz and can be used to trigger an alarm receiver.
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