555 novel long timer circuit

As shown on the figure 6-10, the circuit consists of the hypotension rectifying circuit，reference pulse oscillator， audio switch circuit and executive circuit. The timer circuit's voltage source is 4.8V. The actable multivibrator consists of the IC1 and R1,R2,RP1,C2. The oscillation frequency: f0=1.44/(R1+2R2+RP1)C2. It can be regulated by the RP1. The IC2 is the 9300 music manifold block. It can be controlled by the pulse. Its performance time only depends on the pulse frequency in addition after cancelling its oscillator. The ralations between the IC2's input time pulse frequency and the time are shown on the figure 6-1.