Test equipment varies from the free to the frightfully expensive. Here are some LED related items including the simple multimeter and your camera phone.
Multimeter
For any electronics work a multimeter is essential. At a minimum you require a meter that can measure volts DC and AC, amps DC and AC and ohms. Most digital meters now have a diode test function and a continuity tester with audible beeper. If you intend to pursue electronics as a hobby or profession … Continue reading "Multimeter"
Test infrared LEDs using a camera phone
Infrared (or infra-red) LEDsĀ emit light at a wavelength invisible to the naked eye. This makes it difficult to tell whether the LED is working or not – TV remote controls with suspect battery or bad connections being a prime example. Fortunately most digital camerasĀ are sensitive to IR and can be used to test infrared LEDs. … Continue reading "Test infrared LEDs using a camera phone"
Simple stepper-motor test using LED
An LED can be used as a simple stepper motor continuity tester. Motors act as generators when driven and a typical stepper motor will generate a low voltage / low current output when spun by hand. This is enough to light an LED. The technique can be used to figure out motor winding pairs and … Continue reading "Simple stepper-motor test using LED"
Testing unknown LEDs
Many of us have assorted LEDs in bags, boxes, drawers and old circuit boards. With clear packaged devices we can’t even tell what colour they are! Without markings a simple means of testing the LEDs is required. Here is a safe test method for most LED types. LEDs require a current limited power supply. A … Continue reading "Testing unknown LEDs"