Color multiplexing through fiber optics

If you want to go high bandwidth, fiber optics is the way to go. From trans-oceanic cables to the yet-unseen ‘fiber to every home,’ fiber optics allows a lot more bandwidth than a copper cable. In low-bandwidth applications, fiber optic cable transmits data using one color of light. There’s a way to get more bandwidth out of a fiber optic Read the rest

Upgrading RAM in an Arduino Mega

[Andy] stuffed some more RAM onto an Arduino Mega and his three-part walk through on the design, construction, and software is a great read and one of the more ‘hard core’ Arduino builds we’ve seen.

The build is centered around a 512K × 8 SRAM module [PDF warning]. Because the RAM is divided up into about 512,000 chunks … Read the rest

A beginner’s guide to LED matrices

led_tutorial

[Rajendra Bhatt] wrote in to share a tutorial he put together demonstrating the basics of using LED dot matrix displays. While this subject might be old hat to many out there, his helpful walkthroughs are geared more towards beginners who are exploring various electronics concepts for the first time.

He explains the theory behind LED displays using a PIC-driven … Read the rest

Digital clock building

clock

[punkky] has been documenting his adventures building digital clocks. They each use six 7-segment LED displays, but he’s been gradually changing how they are built. The first version used a CMOS BCD-to-7-sement latch on each display, which is tied to a PIC16F627a. For the next run, he added multiplexing, so he could drive all the segments using just thirteen … Read the rest