Circuit Project Electronic

This circuit designs to upward for divide by the frequency of a signal input , give down left just the half then to export come to the way output. Because of the transistor Q1 (BC549) bias stay the condition not active it then active get especial while signal input be positive volt only. This circuit modifies from oscillator model colpitts , Tank Circuit that compose L1,C4 and C5 can fine about 16.5 kHz. When get a signal input 30-60kHz the circuit lock and oscillator Generator in 15-30kHz frequency detail other sections , please see in the circuit be lucky yes.

Many applications require a sinusoidal reference voltage synchronized to the ac line voltage. You cannot derive such a reference voltage directly from the ac line because the waveform of the ac line is distorted because of nonlinear loads connected to the line and because the amplitude of the line signal varies. Hence, you cannot use a simple step-down transformer to derive the reference signal.[...]

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A friends at use the battery often meet a problem electric its energy is finished in important always may many good if there is the circuit warns before or there is the way checks at the beginning. By this circuit use the transistor just one and don’t have to have power supply source. By this circuit designs to come to use battery 3V - 15V. By fining decorates with VR1. When level voltage agree more location dot keeps LED1 as a result bright immediately. This circuit uses electronic part the a little , then easy in building , request friends , enjoy please yes.