Electronics-Lab.com Blog

A logic analyzer is useful in electronic development and debugging, especially where fast logic circuits are involved with lots of signals whose relations have to be verified or examined. A logic analizer is a like a recorder for digital signals. During a certain (small) period of time, the state of a few digital lines can be recorded to a file. An event can be specified to signal the start of the recording, i.e. line 1 toggeling from 0 to 1.  This recording can be viewed afterwards, allowing for zooming and scrolling in the time domain.
In this page a homebuilt logic analizer is presented.

A logic analyzer using the PC’s parallel port – [Link]

Let’s build a simple digital oscilloscope.

• Single channel 100MHz/100MSPS (100 mega-samples-per-second)
• RS-232 based (we’ll look into USB too)
• Inexpensive!

A simple digital oscilloscope recipe
Using parts from KNJN.com, here are the basic items of our recipe.
1 x Pluto FPGA board, with TXDI and cable (item#1121, $39.95)
1 x Flash acquisition board (item#1205, $39.95)
1 x BNC (item#1250, $4.95)
1 x Nylon standoffs (item#1270, $0.95)
1 x Male/female connectors 2×8 (item#1275, $2.95)
That’s about $88.75 so far.

Hands-on – A digital oscilloscope - [Link]

If you want to build a simple and inexpensive digital voltmeter here is a mini 3 digit display digital voltmeter (this one PIC version).It’s an AVR based voltmeter module.The module has general purpose digital IO pins. You could use it as well to read a digital sensor and display the value.It can be freely programmed, calibrated and even be programmed with a non linear formula. It’s a display where you can define the relation between the measured value and the displayed number. [via]

Mini 3 digit display digital voltmeter - [Link]

Author writes:This watt meter project is very similar to my last wattmeter project. The main reason I made a new project is becasue I needed a unit which could handle higher power than 1W. I found a 50 ohm dummy load which could take 50W of power. Of course I could use attenuates for my 1W meter, but I prefered to build a new unit. The new thing with this project is that it will only display the power in Watt on the LCD display. This means that I will not need so many EEPROM to store display data (more about this later).First we need to update our knowledge how to measure RF power: Some figures and text comes from my last wattmeter project, but it can be good to read it to remember. [via]

Digital Wattmeter - [Link]

This project is a clock that displays the time and date on seven segment led displays.Designed by Perry Andrews.Two buttons are used to set the time and date. The program takes care of changing the date and keeping track of leap years. He recommend all displays are purchased at the same time otherwise a difference in brightness may occur. This page contain documentation, circuit diagram, ‘C’ program and Hex code. [via]

Digital Clock - [Link]

This article shows you how to build a digital thermometer from the beginning to the end, using a thermistor and a 8051 microcontroller.Being based on tutorial about Analog to Digital conversion on this website , it is very easy to understand the functioning of the device, and you can build it with any microcontroller even if it doesn’t have a builtin ADC.This digital thermometer built with the AT89S52 microcontroller. [via]

AT89S52 based Digital Thermometer - [Link]

This is PIC16F628 and pic16f84 base inductance/capacitance meter design by Phil Rice VK3BHR.Measuring range is from 0 to >0.1uF for capacitance and 0 to >10mH for inductance.Expected accuracy is +/- 1% of reading +/- 0.1pF or +/- 10nH.This project is a combination of two stolen designs.The oscillator design originally came from the AADE LC meter web page. It uses an LM311 comparator with positive feedback to make a parallel LC oscillator with digital output. It seems to oscillate readily over a wide range of L and C values. Hopefully, it follows the “well known formula for resonant frequency”.The frequency measuring part is a cut down version of the September 2002 Frequency Meter article from Amateur Radio magazine. The original idea for this came from the web pages of Eamon Skelton, EI9GQ. [via]

Surprisingly Accurate Digital LC Meter - [Link]

This circuit measures temperature in Celsius scale and displays it on an alphanumeric LCD screen
When temperature rise to 40 C an alarm is activated and at the same time a relay is also activated which
drives a fan to keep the temperature at a level. Another feature of this circuit is that you can use the keys “1,2,3,4″ of a Philips TV IR remote to turn on or off three relays, The key ’4′ is used to turn on or off the over temperature alarm.

IR Digital Thermostat for FAN - [Link]

The experimenter’s pot is a solid state potentiometer using Dallas semiconductor’s DS1869 and National’s LM78L05 two electrolytic capacitor two small push button switch and two optional Molex connector. this project is very useful especially in finding the right value of resistor in your experiments, you can attach this circuit to your next project that uses a pot or trimmer cause there are three types of DS1869 these are:

- DS1869-10 which is 10K
- DS1869-50 a 50K version
- DS1869-100 the 100K version

The experimenter’s pot – Digital Potentiometer - [Link]

If you want to know your digital IC fail or good this project can help you.this is an Integrated Circuit tester (IC tester) is used to test Integrated Circuits (ICs). We can easily test any digital IC using this kind of an IC tester. For testing an IC, we need to use different hardware circuits for different ICs; like we need a particular kind of tester for testing a logic gate and another for testing flip flops or shift registers which involves more complication and time involved will also be more.This project use 8951 microcontroller. [via]

Digital IC tester - [Link]