- Recent Releases
- Most Viewed
- Most Liked
A bipolar junction transistor (BJT) has three regions, where the emitter and collector are respectively made of the same type of semiconductor (npn is n, pnp is p). If you consider the base and emitter terminals, or the collector terminal, you get a P-N junction diode. But if we hold the collector and emitter terminals, we will encounter two diodes connected back to back.
3
0
0
Now, you don’t need to worry about the dark night when the power is interrupted. This is a circuit diagram based on a white LED. When the mains power fails, the emergency light will automatically turn on.
0
0
0
For fault diagnosis of any logic circuit, you need a probe clock activity that can test the logic level or existence. The circuit shown here can be used to test CMOS and TTL logic circuits, as well as the presence of clock activity from a few hertz to more than 10 MHz.
2
0
0
This is a circuit diagram of automatic closing renewal. When your rechargeable battery is exhausted, the smart charger will automatically close the charging.
3
1
1
When the water temperature is lower than the set lower limit, this circuit will turn on the heater and automatically turn off the water heater when the temperature rises to the upper limit.
0
0
0
"Ding Dong Bell" is a popular nursery rhyme, and Shakespeare used it in many of his plays. Nowadays, jingle bells are commonly used in mobile phones and doorbells. This is a simple clang generator circuit around a dedicated analog signal.
1
0
0
Here is a simple oscillator circuit that uses a crystal to generate a frequency of 50 Hz. 50Hz alternating pulse with 50% duty cycle can be used in inverter circuit. It includes a 14-stage counter and oscillator (CD4060), dual J-K flip-flops (CD4027), operable amplifier (LM324) and other components.
3
0
0
Using this circuit, check whether a given transistor is good or bad before soldering. This circuit can easily identify npn and pnp types. The tester will indicate the position of the pin and the working condition of the transistor through the LED.
3
0
0
Multiple phones are reminded in different rooms. The low-cost 2-tone ringtone IC LS1240 is usually used as a telephone circuit. As long as the telephone line is extended to the place where additional ringtones are to be installed, multiple rooms can share one number.
5
0
0
In earlier carbureted vehicles, the ignition was mainly by the contact circuit breaker (CB) ignition system. This circuit can convert the car's ignition system from a CB point and condenser type to an electronic transistor switch.
3
0
0
Do you often encounter the need to add a phone bell in another room to remind you of incoming calls? The low-cost 2-tone ringtone IC LS1240 is usually used as a telephone circuit, as long as the telephone line is extended to the place where additional ringtones are to be installed.
0
0
0
We humans can only hear sounds up to 20kHz. Two special ultrasonic transducers should be used: one transducer emits 40kHz sound, the other transducer receives 40kHz sound and converts it into electrical changes of the same frequency.
1
0
0
The simple and practical circuit here is an AC voltage indicator. The AC power supply indicating voltage is composed of three different LEDs. The AC voltage indicator circuit can be made and assembled for beginners.
2
0
0
This unique anti-theft alarm uses invisible and inaudible ultrasonic waves to detect movement of objects. Ultrasonic transducers can work at the highest efficiency under the frequency of 40kHz. Therefore, this circuit uses an ultrasonic transmitter and receiver operating at 40 kHz to control the buzzer or relay.
1
0
0
This simple circuit can scan 220V charged wires. The clock input of the IC is connected to the wire and used as a sensor. Here, a 10cm-long 22SWG wire is used as the sensor.
203
3
2
This simple circuit for monitoring the status of fuses and utility power is very useful for AC power equipment. Sometimes these devices suddenly stop working, and there is no backup device. At this time, it may just be a blown fuse. This circuit helps to identify such problems.
43
0
0
The absolute necessity of every electronic laboratory is the power supply of the bench. The power supply should be regulated and protected to prevent short circuit of the working power supply.
11
0
1
If your car is equipped with an FM radio with stereo output but does not have a built-in cassette tape player, this circuit will facilitate you to listen to your favorite music collection through your personal audio player or use an FM stereo car radio.
28
0
0
Here is a tester, used for the infrared receiver module of TV remote control for vehicle test and VCD player test. This circuit is very simple and can also be used as a remote tester.
9
0
0
If there is a sudden power failure at night, the circuit will automatically turn on to provide sufficient light for about 30 seconds (expandable), which is enough to initiate emergency response measures or light candles.
8
0
0