# Application of CRO, working of CRO

In this article we will discuss about the Application of CRO and their working . we will also learn about the main  application or CRO.

## Application Of CRO

The modern cathode ray oscilloscope provides a powerful tool for solving problems in electrical measurements. Some important applications of CRO are.

### 2. Voltage measurement

#### 1. Examination of waveform:

One of the important use of CRO is to observe the wave shapes of voltages in various types of electronic circuit circuits. For this purpose the single under study is applied to vertical input (vertical deflection plates) terminals of the oscilloscope. The sweep circuit is set to internal so that saw tooth wave is applied to the horizontal input that is horizontal deflection plates. Then various controls are adjusted to obtain sharp and well defined signal wave form on the screen.these are main application of CRO.

#### 2. Voltage measurement

As discussed before, if the signal is applied to the vertical deflection plates only, a vertical line appears s on the screen. The height of the line is proportional to peak to peak voltage of the applied signal. The following procedure is adopted for measuring voltages type application of cro. By this application of cro these can do…
1. Shut off the internal horizontal sweep generator.
2. Attach a transparent plastic screen to the face of oscilloscope. Mark off the screen with vertical and horizontal lines in the form of graph.
3. Now, calibrate the oscilloscope against a known voltage. Apply the known voltage; say 10V, to the vertical input terminals of the oscilloscope. Since the sweep circuit is shut off, you will get a vertical line. Adjust the vertical gain till a good deflection is obtained. Let the deflection sensitivity be V volts /mm.
4.  Keeping the vertical gain unchanged and apply the unknown voltage to be measured to the vertical input terminals of CRO.
5. Measure the length of the vertical the obtained
Let it be l mm.
The, unknown voltage = L x V volts.

#### 3.  Frequency measurement

The unknown frequency can be accurately determined with the help of a CRO. The steps of the procedure are as under. which are basic application of CRO.
1. A known frequency is applied to horizontal input and unknown frequency to the vertical input.
2. The various controls are adjusted
3. A pattern with loops cut by the horizontal line gives the frequency on the vertical plates and the number of loops curt by the vertical lien gives the frequency on the horizontal plates.

### Working of CRO ( Cathode ray oscilloscope).

The oscilloscope is an electronic measuring device which provides a visual presentation of any wave form applied to the input terminals.
Cathode Ray tube (CRT) like a television tube provides the visual display of the signal applied as a waveform on the front screen. It is also known as cathode Tay oscilloscope (CRO).

#### Block Diagram of CRO

For better understand CRO working and application we need to know about the block diagram of CRO.

### Block Diagram of CRO

For knowing about CRO working and application we required to also know about the block diagram of CRO.
The Block diagram of CRO is shown below. It consists of various elements which must be known to us to understand the proper functioning of CRO.

#### 1. Attenuator

The input signal should be  attenuated to a suitable magnitude before

it is applied to the amplifier. The attenuators are employed at the input of both vertical and horizontal amplifiers.

#### 2. Amplifier

The amplifiers of an oscilloscope consist of a vertical amplifier and a horizontal amplifier. The vertical amplifiers amplify the vertical input signal before it is applied to the Y-plates. The horizontal amplifier amplifies the signal, before it is connected to the X-plates.

#### 3. Saw-tooth Generator

For better know about CRO working and application we required to know about Saw-tooth generator.
The measuring signal of any shape is connected to the Y-input (plates) and then it appears on the screen. The signal on X-plates should be such that the image on the screen is similar to that on the Y-plates. Hence, a saw tooth signal is required to be connected to the x-plates which make the image on the screen like the signal connected at the vertical plate.
The saw-tooth signal is called the time base signal, and is produced by the saw-tooth generator. The shape of the saw-tooth signal is shown in figure. The time base signal consists of trace, retrace and hood-off period.

#### 4. Gate Amplifier or Z-amplifier

It is desirable that the image seen on the screen of the CRT must be continuous. The electron beam is desired to appear only in the trace period of the time base signal. The retrace period of the electron beam must not be visible on the screen. Therefore, the gate amplifier is required to control the electron beam in order that itâ€™s appears only in the trace period. It is very important for CRO working and application.

#### 5. Trigger (Gate Amplifier Output)

As mentioned earlier, the measuring signal waveform is connected to Y-input, which appears on the screen.
In order to make the waveform stationary on the screen, it is required that the starting point of the time base signal has to be fixed related to the signal connected to the Y-input. This is known as synchronization.
There are three forms of triggering in an oscilloscope. For better know about CRO working and application we need to know about this.

#### 1. Internal triggering

The signal which is supplied to the trigger is the internal signal of the CRO produced by using the signal form the vertical input signal.

#### 2. External triggering

The signal which is supplied to the trigger is the external signal, produced by using the signal from the external synchronous.

#### 3. Line Triggering

The signal which is supplied to the trigger is the signal from the power supply of CRO (not shown).
Switches are provided to select the form of triggers as required. In a CRO, suitable timing can be selected that causes the image on the screen to be stationary.

### Application of CRO

1. Measurement of current
2. Measurement of voltage
3. Measurement of frequency
4. Measurement of inductance