Digital Storage Oscilloscope

A digital storage oscilloscope is a special kind of storage oscilloscope that stores the input signal for years and displays it on a CRT screen when desired. Digital storage oscilloscope (DSO) is totally reversed to the working of analog storage oscilloscope. In the analog storage (ASO)oscilloscope the input signals are stored in mesh storage and whenever the signal display is needed the electron beam(or)electron gun is activated which hits the mesh storage passing through a horizontal amplifier and finally displays the signal on CRT screen. The stored signal can be used to display for up to few days as the signal has a tendency to fade away. In DSO the operation and working are totally different from that of ASO.

In DSO the signals are stored in digital form rather than in analog form. The conversion of analog signals into digital/binary form can be achieved through Analog to digital conversion(ADC) technique. The converted signal is then stored in memory which acts as a storage unit in DSO. whenever the signal is needed to display on CRT the digital signal is reconstructed to analog form with the Digital to analog conversion (DAC) technique. The below figure is the block diagram of DSO.

 

Working of DSO

When an analog signal is given as an input it passes through an attenuator circuit where the unwanted noise signals are attenuated and this clean signal is applied to a vertical amplifier which performs the sampling and converts the input into digital. The digitally converted analog signal is stored in memory, which we can use as many times as we want to display on CRT. And coming to control logic it controls the ADC(Analog to Digital converter) conversion and deflection amplifiers. Both vertical and horizontal deflection amplifiers are connected to a DAC(Digital to Analog converter) which deflects the beam of electrons and so the trace on the CRT screen. This is the working of DSO.

Advantages of DSO

• DSO is very easy to use and also allows for automation.
• we can store more than one input signal at a time which we can’t do in ASO.
• DSO can display much better-quality images.
• DSO is comparably cheaper than ASO.

Applications of DSO

• DSO can be used in the visual representation of radar targets.
• DSO can be used to measure AC and DC voltages and currents.
• DSO can be used in telecommunications.
• DSO is used as a monitoring device 
• In the nuclear field, scientists use DSO to study environmental changes in absence of terrestrial/cellular signals.

Functions of DSO

DSO is an instrument used to display and analyze electronic signals.It draws waveforms or a graph of an instantaneous signal voltage against time.