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This article discusses various circuits that can be used to test a Transistor, both NPN and PNP. We have structured this article into two circuits. If you have any doubts about any section please ask through comments. 1. Transistor Tester built using Transistors 2. Simple Transistor Tester (Contains both Circuit Diagram and PCB Lay Out)
Description. This is a simple automatic emergency light which remains OFF when the mains power is available and switches ON when there is a power failure. When mains power is available, it is stepped down by transformer T1, rectified by diodes D1&D2, filtered by the capacitor C2 and regulated by the 9V regulator IC 7809
Testing SCR using a multimeter. A multimeter can be used to test SCRs quite effectively. The first procedure is to check the diode action between the gate and cathode terminals of the SCR. This test is just like what you have done in the case of testing a silicon diode (see testing a silicon diode).
Testing triac using a multimeter. A multimeter can be used to test the health of a triac. First put the multimeter selector switch in a high resistance mode (say 100K), then connect the positive lead of multimeter to the MT1 terminal of triac and negative lead to the MT2 terminal of triac (there is no
Diodes are one of the components that can be tested very easily.Ordinary diodes as wells as Zener diodes can be checked by using a multimeter. While testing a diode the forward conducting mode and reverse blocking mode has to be tested separately. Testing ordinary diode using a digital multimeter. To check an ordinary silicon diode
Description. In this circuit the intensity of LED will vary in a ramping fashion. The circuit consists of three ICs: Two 555 timer ICs and one LM393 op-amp. IC1 and IC2 are wired as oscillators to produce 10 KHz and 1 Hz frequencies respectively.These two frequencies are given to the inputs of the op-amp LM393.LM393
Description. This simple circuit will produce an alarm whenever the temperature falls below zero degree. A thermistor is used here to sense temperature. The op-amp LM7215 is used to compare the reference voltage and voltage from the thermistor network. Reference voltage is given to the non inverting input (pin3) of the IC and voltage from
Description. This simple circuit can be used to monitor whether a battery is charging or not. The voltage comparator IC LM393 is the heart of this circuit. The LED D1 will remain ON whenever there is at least 25 milli ampere current flowing to the battery. This particular circuit is designed for a 12V battery
Description. This 1.3V power supply can be used as replacement for the 1.3V Mercury Cell in any circuit. When the input 5V is given to the circuit, the voltage drop across zener diode D1 will be around 2V.The diode D2 will drop a 0.7 V from the 2V volt and the remaining 1.3V will be
Description. Here is the circuit diagram of a simple soft start power supply using the well known IC L200.The L200 is a monolithic IC that can be used for voltage and current regulation. The built-in features such as thermal shut down, over current protection and input over voltage protection makes this IC nearly indestructible. When
Description. Here is the circuit diagram of a simple soft start power supply using the well known voltage regulator IC LM317.Here the IC is wired in soft start mode in which the output of the IC gradually increases to the desired output voltage .When the input voltage is given to the IC , the capacitor
Description. This is the circuit diagram of a simple UPS that can deliver 12V unregulated and 5V regulated DC. The transformer T1 steps down the mains voltage to 12V AC and then the bridge B1 rectifies it. The rectified signal is smoothed by the capacitor C1.When the mains supply is available the battery will be
