Even though they're ancient by today's standards, old tube radios can almost always be brought back to life, and there's still plenty of broadcasts out there for them to receive! Not to mention, they just look so classy and have a presence few modern electronics can match.
Whether you need to flash an LED, energize a relay, turn a buzzer or alarm on or off, or invert a voltage level, the NPN transistor switch can easily solve your problem. This article shows you how to use a transistor as a simple SPST switch.
Most electronic devices today have a single button you push to turn them on and off. Think of your cell phone, laptop, and even your TV. There is no toggle to flip, no knob to turn back and forth, nor slide switch to move. So, how do you get one of these power buttons into your project so your latest gadget can sit next to your other devices without the embarrassment of a toggle or slide switch?
Keeping tabs on relative humidity and temperature is important in a variety of situations. The DHT22 is a recent contribution to the lineup of joint humidity/temperature sensors, and is particularly attractive to DIYers thanks to its low cost. Uncover its secrets to get it working for you.
I examined the almost perfect circle surrounding a stylized “M” (for Motorola) that was branded into the end of my index finger after touching the case of a power transistor to see if it was “warm.” This was my introduction to “heatsink selection for power semiconductors” I received as a young experimenter building a power supply — a lesson I have not forgotten several decades after the event.
A perfect wire should conduct a signal without adding noise, attenuation, or distortion. Whatever is electrically happening at one end of the wire should be happening at the other end exactly in the same form, no matter what the current, voltage, frequency, surroundings, or temperature. However, this isn't the case.
The goal of breadboarding is to mount electronic components on a supporting substrate and make all of the necessary electrical connections that result in a functional electronic device.
I’ll show you two examples of circuits that don't use a micro but are often built with one, and explain some of the logic and theory behind these circuits.
The goal of this series is to introduce you to the world of control electronics. Practical examples will be presented and the math will be kept to an absolute minimum. This is not to say that the math is not important. Quite the opposite — control systems may be modeled and analyzed mathematically. The mathematics is nothing short of amazing and I would encourage you to peruse it.
If you really want to know what makes any wireless application work, it's the antenna. Here, we'll summarize some of the most common types and make you aware of what an antenna really is and how it works.
