Digital lock 4

Posted on Feb 6, 2014

The digital lock circuit is composed of the timing trigger circuit, trick lock circuit, sound and alarm circuit and control implementation circuit, and it is shown in Figure 3-101. Timing trigger circuit is composed of the transistors Vl, V2, resistors Rl-R4, light-emitting diode VL and capacitor C. The trick lock circuit is composed of the password button..

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