Electronic Test Equipment

                                     General Test Equipment

In this article we will discuss about some general testing equipment used in electronic troubleshooting.
Multimeter is one of the most important testing equipment and is absolutely necessary for the test bench. Anyhow more the testing equipment you have more prepared you are for an electronic troubleshooting. 

Multimeter:
Two types of multimeters are available in the market, one is digital and the other is analog. Both of them have the same function but the only difference is that digital multimeter shows digital display. DMM are ranked by the number of digits they display.i.e a "3½ digit" DMM wiil show three digits for each reading.Some advance multimeters automatically choose the correct voltage and resistance range.This feature is called "auto-ranging". DMM  are easier to read and more accurate as compared to the analog multimeters.
Multimeters are available in a wide range of features and prices.The price varies from US$10 to US$5000.
Never test for the continuity in a circuit with DMM  when circuit is energized.For measuring current the DMM should be connected across the circuit. Multimeters practically have no resistance between their leads.

Oscilloscope:
Oscilloscope has a tremendous advantage over the multimeters as it gives the picture of the electronic signal instead of giving value in digits.In oscilloscope not only you can observe the ac and dc voltage but you can also see the shape of the electronic signal.An oscilloscope may be used to check the characteristic parameters of the electronic equipment like transistors,capacitors etc.Don't get an idea that you will need oscilloscope for every electronic troubleshooting.Some dual trace oscilloscope may generate a 2D view of the two electronic signals at the same time in this way you can check the time relationship between the two respective signal.

Transistor tester:
Digital multimeter can perform some simple test regarding transistor however for testing the transistor very deeply special transistor tester is used.It allows you to perform in-circuit test i.e you can test the transistor without removing it from the circuit.The tester allows you to check the working of the transistor and also "voltage gain" can be checked.Most of the transistor tester can also be used to measure the diodes.

Frequency counter:
Frequency counter is useful for checking the frequency of the signal coming from a computer & clock signal of the monitor microprocessor.Some DMMs have a built in frequency counter.
Simple handled multimeter can measure a frequency of about 100kHz while bench top multimeters can measure upto 10MHz.

DC power supply:
A device that provides a smooth dc voltage at the output while input is ac is termed as dc power supply. In most of the dc power supplies desired dc output voltage can be obtained.

Capacitance meter:
In order to measure the capacitance of a capacitor capacitance meter is used. Capacitance meter usually shows the value in micro-farad(µF), nano-farad(nF), and pico-farad(pF). For electrolytic capacitor an ESR meter is used. Some DMM are also provided with built in capacitance meter. Keep in mind that a capacitor should be discharged before testing it.

Inductance meter:
Inductance meter is required to determine a coil or a winding value.It is also known as LCR meter.Most of the inductance meter comes together with capacitance and resistance measuring facility.
It will usually measure the value in Henry(H) mili Henry(mH) and micro Henry(µH).

ESR Meter:
It is an equivalent series resistor.The equivalent series resistance can not be measured by multimeter or capacitance meter.It can only be measured by the ESR meter. ESR meters come in various sizes shapes and brands.