How nice to fall asleep to the rhythmic roar of the rain, as the happy jingle of the spring thaw! But should we depend on the vagaries of nature, when all you can hear at any time at home. It is enough to make a simple electronic device, based on a well-known multivibrator. Changing the position of the slider of the variable resistor R2 (see diagram), adjust the rhythm of the speakers B1 and B2. The device is powered from a single battery 3336L. Selecting the values of resistors and capacitors, achieve a pleasant timbre of the device. VOSKRESENSKY, Kuibyshev
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