Two alarm circuits are presented here. One produces bird-chirping sound and the other British police siren tone. Fig. 1 shows the circuit of the birdchirping- sound alarm unit along with the circuit of the control unit. Fig. 2 shows the circuit of only the British police siren tone generator, which has
to be integrated with the control circuit portion of Fig. 1 at points A and B to complete the circuit diagram of automated alarm

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