Category Archives: Electronics History

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 [...]

What is Vapor Phase Reflow Soldering?

Vapor Phase Reflow Soldering is an advanced soldering technology. This is fast replacing other forms of soldering processes manufacturers presently use for assembling printed circuit boards in high volumes for all sorts of electronic products. Soldering electronic components to printed circuit boards is a complex physical and chemical process requiring high temperatures. With the introduction of lead-free soldering, the process is more stringent, required still higher temperatures and shorter times. Read more [...]

Why do Speakers use Ferro-fluids?

Speakers reproduce sound by moving a diaphragm to displace air. The mechanism resembles a permanent magnet electric motor. The major difference is the voice coil in a speaker moves linearly instead of in a circular motion. As the coil moves back and forth in step with the electrical signals fed to it, it moves the attached diaphragm. To prevent spurious movements and unwanted oscillations of the diaphragm, conventional speakers generally use a damper. To produce sound from such speakers, extra energy Read more [...]

What You Need To Know About EMI Antennas

Any electronic device, system or subsystem generates EMI or ElectroMagnetic Interference and is susceptible to EMI generated by others. To allow them to coexist and cooperate, all such electronic devices, systems or subsystems must confirm to specific standards, which limit the amplitude and frequency range of EMI generated and tolerated by each of them. Testing for such radiated emissions and immunity involves EMI chambers and OATS or Open Area Test Sites. To check for EMI generated, these chambers Read more [...]

What is Digital Signal Processing?

Initially, when DSP or Digital Signal Processing was introduced over thirty years ago, it involved standalone processing. A single micro-controller handled all the parameters for processing the analog signal and transforming it to its digital value. Evolution in this area has introduced multicore processing elements that now extend the DSP's range of applications. Simultaneously, evolvement of software development tools for the DSP now allows expansion for accommodating diverse programmers. Therefore, Read more [...]

Let Raspberry Pi Track Bats for You

If you live in an area that has fruit trees around, it is likely bats share your space. Bats are furry mammals that flit about at night, feasting on insects and fruits. Although they are not gifted with good eyesight, they locate prey and avoid obstacles using echolocation. They are expert fliers and it is difficult to observe them since they are so silent. Although humans cannot hear bats, it does not mean these creatures make no noise. In fact, using the process of echolocation, bats produce Read more [...]

What are Leadless Packages?

Electronic components, especially semiconductors have undergone a dramatic transformation over the past few decades. Starting from the through-hole packages, semiconductors evolved into the surface mount packaging, which is the default today. With the increase in packaging density, surface mount packaging is now limited to passive components mostly, while semiconductors are moving towards current technologies involving leadless packaging. Modern technologies involve leadless packaging such as Read more [...]

What is a 4-20 mA Current Loop?

The pre-electronic industry used pneumatic controls. Compressed air powered all ratio controllers, temperature sensors, PID controllers and actuators. The modulation standard was 3-15 pounds per square inch, with 3 psi standing for an active zero and 100% represented by 15 psi. If the pressure went below 3 psi, an alarm would sound. Electronic controls made their debut in the 1950s. A new signaling method with 4-20 mA current emulated and replaced the 3-15 psi pneumatic signal. As wires were Read more [...]

What is a capacitor used for?

Just as a bucket holds water, a capacitor holds charge. In fact, the world's first capacitor was in the shape of a jar and was aptly named the Leyden jar. However, the latest capacitors do not look anywhere close to a jar. In its simplest form, a capacitor has two conductive plates separated by a dielectric. This helps maintain an electric charge between its plates. Depending on the type, different materials are used for the dielectric, such as plastic, paper, air, tantalum, polyester, ceramic, etc. Read more [...]

How did the diode get it’s name?

Although most diodes are made of silicon nowadays, it was not always so. Initially, there were two types – thermionic or vacuum tube and solid state or semiconductor. Both the types were developed simultaneously, but separately, in the early 1900s. Early semiconductor diodes were not as capable as their vacuum tube counterparts, which were extensively used as radio receiver detectors. Various types of these thermionic valves were in use and had different functionalities such as double-diode triodes, Read more [...]