Low Voltage Test (CB22158E)

This is a simple voltage tester for voltages from about 2V to about 15V with the indicated resistor and red LEDs.

Crystal Pierce Oscillator with Bipolar Transistor (CB13120E)
The original frequency of the Pierce Oscillator with bipolar transistor is given by the crystal, which...
Automatic Hand Dryer (CB17658E)
Of course, the design indicates a specific application for a touch switch. Thus, analyzing the...
Low frequency converter (CB9336E)
This circuit converts signals from the 350 to 500 kHz band to the 4.36 to 4.5 MHz band, enabling...