Checker Circuits
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By using a simple visual indicating system, this small transistor tester allows you to run a quick go/non-go` check on NPN as well as PNP transistors. If the device under test is a working NPN then the green LED (D1) will‚ash, while the red counterpart.... -
This little circuit is invaluable for quick go/no-go testing of just about any remote control transmitting infra-red (IR) light. The tester is battery-powered, built from just a handful of commonly available and inexpensive parts, and fits in a compact.... -
Liquid-crystal displays come in all sorts and sizes, and this applies also to their pinouts. In fact, many of these displays cannot be used properly without the manufacturers` documentation. But, of course, this can never be found when it is needed, and a.... -
The continuity tester can distinguish between high-, medium-, and low-resistance connections. When there is a conductance between the inputs, which are linked to small probes, a current flows from the +9 V line to earth via R1 and R2. The consequent.... -
The circuit in the diagram is a very handy tool for rapidly checking all kinds of thyristor (SCR, triac, ). In case of a triac, all four quadrants are tested, which is done with S3, while in case of a standard thyristor, a positive power supply and trigger.... -
Today, most telephone equipment use a DTMF receiver IC. One common DTMF receiver IC is the Motorola MT8870 that is widely used in electronic communications circuits. The MT8870 is an 18-pin IC. It is used in telephones and a variety of other applications..... -
Nearly always when a remote control doesn`t work, the underlying problem is elementary: the unit does not emit light. The cause may be dry solder joints, defective LEDs etc. , but also a flat battery (perhaps due to stuck key). The human eye is unable to.... -
The circuit depicted is the receiver device of a transmitter/receiver combination that will prove extremely handy when tracing the path of electrical wiring in a building or to locate a break in a wire. The corresponding transmitter may be found elsewhere in.... -
The circuit depicted here forms one half of a device that will prove extremely handy when tracing the path of electrical wiring in a building or to locate a break in a wire. The system is based on similar equipment that is used by technicians in telephone.... -
Here is an infrared remote control tester circuit that can be made without spenting much money. This IR tester build around an infrared reciever module TSOP1738. We can observe the remote control state by listening to the buzzer sound. The circuit is very.... -
How to measure water purity How to test water quality using a simple electronics project You can perform water purity measurement and water quality analysis using this water purity checker circuit. This circuit is built around a simple LDR (Light Depended.... -
Here the NE555 is wired as an astable multivibrator. When the push button switch S1 is pressed the LEDs D1 & D2 will flash alternatively. That is when output is high D2 will glow & when output is low D3 will glow. The rate of flashing will depend on.... -
A simple humidity tester circuit using just a LED, transistor, and a few resistors is explaind with a neat circuit schematic.... -
Here is the circuit of a very simple transistor tester which used two LEDs for displaying the condition of a transistor. Both PNP as well as NPN transistors can be tested using this circuit. Quad 2 input CMOS NAND gate IC CD4011B is the heart of the circuit..... -
This a very simple and inexpensive circuit that can be used to test quartz crystals. Here a Colpitts oscillator is wired used the transistor T1. When the crystal is connected between terminals A and B the circuit will produce high frequency oscillation. The.... -
A simple remote control tester circuit with diagram and schematic using infra red sensor IC TSOP1738. An LED will blink when IR waves falls on it which indicates remote control functioning.... -
When S2 is ON, the circuit here operates as an astable multi vibrator and the LED is lit for about o. 1sec, flasing every 1. 5 seconds. Since the human reaction time is more than this, you cannot catch it once it is seen o, by pressing S1. If your sense of.... -
Here is a very simple circuit that can be used to check the hfe of transistors. Both PNP and NPN transistors can be checked using this circuit. Hfe as high as 1000 can be measured by using this circuit. The circuit is based on two constant current sources.... -
This circuit can be used to test whether mains voltage is present or not without having electric contact with mains line. The CMOS IC CD4033 is the heart of this circuit. The CD4033 consists of a 5 stage decade Johnson counter and an output decoder for.... -
Here is a very simple circuit that can be used for testing Zener diodes. The IC1 NE555 is wired as an astable multivibrator and the output of the IC is stepped up to a high voltage AC using the transformer T1. The unloaded AC voltage will be around 120V. The.... -
Improved Vibrating Battery Tester. This Circuit Based On The LM393 IC. Features: to test the batteries,It will test AAA, AA, C and D cells, as .... -
This circuit shows about Go-No/Go Tester Circuit With 555 Timer IC. Features: more advanced unit with a precise timed testing procedure. .... -
This circuit can measure both small signal hfe and DC current gain hFE of a low to medium power power transistor.... -
A circuit of an off-line telephone tester which does not require any telephone line for testing a telephone instrument. The circuit is so simple that it can be easily assembled even by a novice having very little knowledge of electronics. A telephone line.... -
Is a capable tube tester, yet its use scenarios can be multiplied with only modest efforts invested in understanding its schematic, regimes, and ways to add new regimes. Eico 666 is capable tester, known to be able to supply voltages and currents adequate.... -
Most of the time a charged lead-acid battery and a power inverter would be used to ensure a smoothly organised holiday where ideally the missus and the children cheerfully use their electric and electronic gear! With rechargeable lead-acid batteries it`s.... -
The simple transistor tester in Figure 1 lets you identify the type of transistor, and it helps in detecting a transistor`s emitter, collector, and base.... -
Yes, it does charge the inductor again. Diodes are a good that they will not charge the inductor back but of course dissipate fair amount of instantaneous power due to the forward voltage drop. One way would be to monitor the current and stop driving those.... -
The present tester is intended primarily for testing the 24 V electrical circuits found on most pleasure craft. However, if the resistors are given different values, the circuit may, of course, be used for other voltage ranges. For 12 V, the value of the....
New Circuits
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This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of.... -
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is.... -
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to.... -
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This.... -
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the.... -
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,.... -
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the.... -
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power.... -
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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