2 min 0

MDL-150 Electronic load and battery tester review

The MDL-150 battery capacity tester and DC electronic load A great inexpensive unit that performs as expected and is really good value for money. User interface could use some improvement but otherwise I highly recommend it for hobbyists for occasional use. Oh yeah, throw away the dangerous power supply that comes with it and use […]
Read More
2 min 3

SPI driver board for large 2-8″ 7 segment displays

As part of a collaboration project through contact with a member of Instructables who had seem my large LED clock project I made some serial driver boards for his project adapted from mine which uses 4″ high LED displays and uses the decimal points as the colons with alternate digits inverted. These driver boards are […]
Read More
1 min 0

How to determine the pinout of an unknown 7 segment display

If you have an unknown 7 segment LED display and you want to use it in your project, you need to determine its pinout. The pinout is the arrangement of pins that connect the display to the power supply and the controller. There are different types of 7 segment displays, such as common anode, common […]
Read More
2 min 0

Call centre calls waiting and LED matrix display teardowns

I recently acquired a few scrap Seltek (now Avaya) wallboards from an insurance company’s call centre, and they turned out to be quite intriguing. Among the items were three call waiting monitors and a SDX ACD scrolling message display, also known as a “wallboard.” What caught my attention were the separate LED modules in the […]
Read More
3 min 1

Re-using a microcontroller from a LCDmodkit USB204B.V02 board

On one of my very old computers I had one of those LCDmodkit PC status screens that consisted of a 20×4 LCD housed in a 5.25″ bay and was interfaced to an internal USB header on the motherboard via a USB2LCD controller. As there are no Microsoft certified drivers available for this device it was […]
Read More