Voltmeter Construction

Amplifier, Oscilloscope, Printed circuit board


The objective of this project is to design LCD digital oscilloscope for practical use. The basic concept for the project involves reading the voltage signal at the input and displaying it on the screen of an alphanumeric LCD. The input analog signals are supplied to the ADC(Analog to Digital Converter), which are then sampled by it and the amplitude of the signal(voltage) is displayed on the LCD.

Device Components:

Microcontroller or processor:

We used Atmega16- an Atmel AVR series microcontroller. The processor clock was set to 11MHz internal oscillator.

Analog to Digital Converter:

In this device we use Atmega16’s inbuilt analog to digital converter. It is a 10-bit ADC which uses the in-built reference voltage level of 2.5V.

Software Implementation:

The programming required, reading the input signal from the ADC pin and then to display the voltage on the alphanumeric LCD, is done using Bascom-AVR.

Though the features of an actual oscilloscope have been compromised upon but the essence of its hardware has been conserved by implementing a voltage reading device.



The oscilloscope is one of the most important tools to be used by any electronics hobbyist but not everyone can afford to have one. As commercial scopes are often too expensive, almost every electronics hobbyist thought at a certain time to build one from scratch. The classical oscilloscope (cathode ray tube) is difficult to build at home because of its size, mechanical fragility, high voltage presence, etc. An alternative solution is the modern “PC oscilloscope”, having the advantage of post processing and recording capabilities, and kind of reduced complexity. However, this solution is often non-portable, expensive (requires a PC) and dangerous for the PC if not isolated from its chassis. The third solution is commonly used these days by all commercial oscilloscope manufacturers, is the digital...
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