The voice reporting circuit consists of a nose switch, a trigger timing circuit, a voice circuit and a power supply circuit, as shown in the figure.
The nose electronic switch consists of a model rubber nose and its linked switch SA amplifier VT1. Normally, the SA is in the off position. When the player touches the elastic nose before closing the eyes, the switch SA is closed due to vibration, VTl is biased and saturated, and the tube pressure drop of o.3v causes the IC1 to trigger. Bit.
IC1 uses time base circuit 555, which forms a trigger timer with R3, Cl, etc., once its 2 pin gets low power (<1/3VDO) trigger, it is set and timed, and its timing depends on C1 through R3. The time constant charged to 2/3 VDu, ie td=1.1R3C1, is designed to be 10 seconds.
IC1's high-power output provides operating power for IC2. IC2 uses the voice integrated circuit KD-56023, which has a "haha laugh" voice signal. The statement length is 3 seconds. Each time it is triggered, the laughter will cycle for three cycles. The typical working voltage of the chip is VDD=3V. This circuit directly connects its trigger terminal TRIG and the power supply VDD. During the high level after IC1 is set, it simultaneously receives power and triggers, and immediately plays the "haha laugh" sound. It shows that the player has succeeded in the nose. The quiescent current of KD-56023 is about 1?A, and the current consumption of the electrode is small.
The step-down rectifier circuit is composed of a step-down capacitor C5 and a rectifier QD and a filter capacitor C4. The rectified DC voltage is regulated by R6 and DW2, and the voltage of +9V is regulated as the supply voltage of ICl and IC2. The step-down capacitor C5 should be a non-polarized metallization capacitor with a withstand voltage of not less than 400V.
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