Dilshan R Jayakody’s Web Log

This is PIC16F73 base digital data capture unit with optional EMF reader. This data capture utility is design to work with most of the analog sensor inputs and by default, it is equipped with the EMF reader module. This unit use PIC16F73's internal 8bit ADC to capture the analog signals. EMF reader unit in this schematic is useful to detect variations of EM field in the environment and it is mainly built around uA741 operational amplifier and 12mH detector coil . Normally EMF meters are used to trace electric wires, find hidden transmitters, and diagnose electric wiring problems ( and to find ghosts too ☻ ). This digital data capture unit can operate in 2 modes. In the first mode, it directly converts an analog signal into digital data and transferred to the host via a serial interface. In second mode it displays captured signal in 5 LED bar graph either slow or high-speed capture modes. This unit is designed to work with 5V 500mA power source and to get optional EMF reading...

This is an easy to construct precision electronic event logger and using this we may be able to measure time differences in two events in range between 0.02 seconds to 6.8 seconds. This system is mainly design around PIC16F73 microcontroller and 4040 binary ripple counters. The main counter clock (reference counter) is oscillated around 2MHz. Most of the counter related components of this system are based on CMOS family of ICs. If you need more precious lower limit it is recommended to replace all these CMOS family of ICs with TTL equivalents (e.g: 4027 by 74HS73 with slight changes and 4040 by 74HC4040). The clock frequency of the existing counter can also increase up to 6.0MHz. The counter gets activate and deactivate in positive edge of the input signal. Thanks to the wider operating voltage of the CMOS ICs this counter may be able to handle +5V to +15V of input signal. At the end of the counter session system release total tick count to the RS232 interface and it can receive t...

This is simple PIC microcontroller base project to generate Morse codes using standard PS/2 keyboard. This project based on Microchip’s PIC16F73 microcontroller and National semiconductor’s LM386 audio power amplifier. Software for PIC microcontroller is written using MikroC and all the source codes, schematic diagrams and other documents are available to download at here . In this project we choose PIC16F73 because of it’s 4KW (KWords) program memory, it is possible to replace this MCU with any suitable MCU which having 4KW (or more) flash memory. (For example Atmel AT89C4051-24SJ with different source code, Microchip PIC16F648 with some minor changes in source code, etc) Audio power amplifier of this project is based on National Semiconductor’s LM386. We choose LM386 because of its lower power consumption and compactness. User may also replace this module with suitable power amplifier (for example Philips TDA7052, TDA8551, National’s LM4906, etc.) PIC16F73 software is develop...