Using Arduino True Battery Capacity Tester you are able to measure the charging capacitance of Li-Ion/NiMH/NiCD/Pb batteries and display results on character LCD screen or aquire full discharge characteristic graph on PC. Tester supports auto battery type detection and discharge takes from 30-120 minutes to complete, giving you an indication of battery’s quality.
Arduino True Battery Capacity Tester (Li-Ion/NiMH/NiCD/Pb) - [Link]
This liquid level sensor measures the capacitance of the liquid between two electrodes and gives an indication of liquid level inside a bottle. Capacitance is measured by charging the capacitor and measuring the time needed to discharge via a known resistor. The brain of the sensor is an Arduino board.
A capacitive liquid sponsor relies on the fact the the capacitance or charge between 2 metal plates will change (in this case increase) depending on what material is between them. This allows us to create a level sensor that is save for use with any liquid, this one will be used in a buggy with gasoline
Building a Capacitive Liquid Sensor - [Link]
This submini USB scope is based on a Atmel Tiny45 cpu and cost less than 5€ with a homemade pcb. It has 2 analog inputs and can supply 5V ont the 4 pins header on the right. One of the inputs can be scaled down with the trim pot. The firmware in the Tiny45 is written in C and compiled with Winavr and usb source code from obdev.
Simple two channel USB oscilloscope - [Link]
Many people assume that all LEDs can be powered with a constant 3V power source. LEDs in fact have a non-linear current-voltage relationship. The current grows exponentially with the voltage supplied. There’s also the misconception that all LEDs of a given color will have a specific forward voltage. The forward voltage of an LED does not depend on the color alone and is affected by other factors such as size of the LED and its manufacturer. The point is, the life expectancy of your LED may degrade when its not powered properly.
Current Regulated LED Tester - [Link]
Sylvain Bissonnette writes:
This is a simple project. The Frequency is passing through an op-amp to convert it in a square wave. The ouput of the op-amp is feeding the 3*8 bits counter (24 bits) who can accumulate at a maximum of 16777216 count. The maximum frequency you can measure without changing the time base of one second is 16.777216 Mhz. The ATMega8 have 3 functions: enable the counter gate at each second, read his value and display it on the LCD.
ATMega8 Frequency Meter – [Link]
In a previous article I have analized 3 accelerometer side by side comparing their noise level. Today I am going to test a 3 axis accelerometer from ST LIS331AL. I am going to compare it with the DE-ACCM2G accelerometer from Dimension Engeneering.
LIS331AL – ADXL322 Accelerometer benchmarks – [Link]
Very simple thermometer with PIC16F88, two LM35 sensors and KS0108 graphic LCD.
PIC16F88 LCD thermometer - [Link]
This project is a 2 channels amp meter. Those channels are completely isolated up to 2000 volts.It provides auto detection for AC or DC current. The main part of this project is the current sensor ZMC10 a cool DIP 14, which supports up to 10 A. The current is measured inside by hall effect sensor and display data using a graphic LCD of the read current and max peek value, DC or AC
Digital 2 channel 10 Amp Meter - [Link]
In the past, advice on forums has always tended more towards purchasing a second hand scope. These tend to be had for around £100 on places like E-bay and most certainly will be a few years old if available at this sort of price. Well that is changing and I was excited yesterday to get my hands on a “Scope” that may just re-write the forum advice. Meet the Nano DSO from Seed Studio… [via]
Pocket Digital Storage Oscilloscope - [Link]
Everyone knows the problem: You have a transistor, but you can’t read its signature. Or you can’t find the datasheet… You have a diode, but… You have a capacitor, but you can’t read… Here is a smarty solution.
* Automatic Detection of NPN and PNP transistors, N-and P-channel MOSFETs, diodes (including double diodes), thyristors, triacs and resistors.
* Automatic detection and reporting of the pins of the test component
* Detection and display of protection diodes for transistors and MOSFETs
* Determination of the amplification factor and the base-emitter forward voltage of transistors
* Measurement of the gate threshold voltage and gate capacitance of MOSFETs
* Show the values on a text-LCD (2×16)
* One-button operation, automatic shut-off
* Power consumption in off mode: <20 nA
This tester also supports diode measuring, R/C testing, and a lot of other components identifying. [via]
Component checker / tester - [Link]