PiFM: A Pirate Radio with the Raspberry Pi

The popular single board computer, the Raspberry Pi (RBPi), can work as a radio transmitter as well. Using a simple hack, you can turn your RBPi into a powerful FM transmitter with adequate range to cover a bike parade, high school ball game, silent disco, DIY drive-in movie, or even your entire home. However, the broadcast frequency covered by the RBPi is rather large—one to 250 MHz, and there is a possibility this will interfere with government bands. Therefore, it is advisable to limit the transmissions Read more [...]

Colorful Images from Electron Microscopy

Almost everyone treats Christmas as the time to get away from regular work. Surprisingly, there are exceptions, such as Roger Tsien. This late biochemist would do an extra two weeks of uninterrupted research in his lab during Christmas. In one of his sojourns, he gifted the world the first electron micrographs—in color. His method used to create them will dramatically advance cell imaging. Scientists use Electron Microscopy (EM) for magnifying objects up to 10 million times their original size. Read more [...]

Monitoring Batteries Wirelessly

Lithium-ion batteries, when used to drive automobiles, can operate reliably over long periods, but require considerable care. That means not operating them to the extreme ends of their state of charge or SOC. With passage of time and usage, the capacity of a lithium ion cell changes, and therefore, each cell in the system has to be managed so that it remains within its constrained SOC. As vehicle operation requires generating as much as 1000 V or higher, tens or hundreds of cells are necessary, Read more [...]

The Energy Efficient RRAMs

Engineers at Stanford are making 3-D memory chips that can offer faster and more energy efficient solutions for computer memory. These are the Resistive random Access Memory or RRAMs, which are based on a new semiconductor material. It stores data based on temperature and voltage. However, the actual workings of RRAMs continued to be a mystery until a team at Stanford used a new tool for their investigations. They found the optimal temperature range to be lower than they had expected. This could Read more [...]

A Drone-Disabler with the Raspberry Pi

Drones or quad-copters are now affordable, and it is possible to record unique perspectives using their high quality video transmissions. The FAA calls them the unmanned aircraft systems, and these have started posing new challenges to security, safety, and privacy. Experts have started cautioning pilots to consider the implications of the increase in drone usage. Apart from constant surveillance concerns, it is possible for hackers using roving drones to collect location information from mobile Read more [...]

Why not wear Digital Clothes?

We carry so much digital technology on our person all the time; it is quite natural to wonder about digital clothes. Technologists and manufacturers assure us that the field of printed electronics to produce digital clothes will be making significant advances in 2017. We have some indications as to what is to be expected. For instance, there is the safety garment that Flex and MAS Holdings is planning on producing. The garment has LEDs embedded into the fabric. As of now, the manufacturers are Read more [...]

The Next Generation Wireless Audio

We have been seeing wirelessly connected speakers for quite some time now, mainly using the Bluetooth technology. Although convenient, Bluetooth technology has its limitations because of bandwidth and range. The first to overcome this was Sonos who introduced Wi-Fi based wireless speaker system with their SonosNet mesh-networking technology. Several others followed, such as DTS’s Play-Fi, DLNA or Digital Living Network Alliance, and Apple AirPlay among the leading few. The most recent is the Google Read more [...]

Raspberry Pi Goes Binocular

This project uses the popular single board computer, the Raspberry Pi (RBPi) and a spare pair of binoculars to view and take pictures. The LCD on the RBPi is touch enabled to make it easy to capture the images. To start with, you will need the appropriate Operating System for the RBPi. Download the Wheezy Raspbian OS from the Adafruit site, which will make it easy to interface the 2.8” TFT LCD with a capacitive touchscreen from Adafruit. Once download is complete, unzip the image and install Read more [...]

Annoy-Pi: Using the Raspberry PI to Annoy Others

Most of us, as children, have made several attempts at annoying our neighbors. The electronically inclined have attempted circuits producing random chirps, which when hidden in cupboards, produced the most annoying effects. Another was a tiny coin-cell battery operated beeper that produced a beep every minute or so, designed to make people go crazy. Now, you can use the Raspberry Pi (RBPi), the popular single board computer, and try different programs to see which of them can produce the most annoying Read more [...]

How Do You Count People Using Wi-Fi?

Other than providing wireless communication facilities, Wi-Fi can have other uses as well. Researchers at the UCSB are now experimenting with a common wireless signal to tell them the number of people present in a designated space. Astonishingly, these people need not be carrying any personal devices on them. At Professor Yasamin Mostofi’s lab in the UC, Santa Barbara, researchers are demonstrating that wireless signals have more uses than simply providing access to the Internet. With a Wi-Fi Read more [...]