If you’ve been following along with the 555 timer series, this video describes how to derive the formula that describes the timing of the circuit. Starting with just 2 components, we’ll work our way to an answer.
Continuing with a focus on the 555 timer, this video tutorial looks at how to vary the pulse width of a 555 timer’s output. It’s all possible with just a a hand full components. By varying the duty cycle one may vary the blink rate on an […]
For the past several weeks we’ve looked at blinky LEDs, 555 timers, and resistors. This week it’s time to put it all together into an application. A YouTube subscriber suggested the project as follows: How would you go about having an led blink twice, then […]
As we learned from the last video, resistors are helpful when you want to limit current. They are also helpful if you want to divide a voltage level, but in order to do any of this, it’s important to understand all about a resistor’s power […]
In the course of my normal job, it’s surprising how often field expedient solutions are used to solve a problem. However, those field expedient solutions are impossible unless you understand the underlying principles involved. In this video I’ll look at Ethernet infrastructure, discuss how it works, […]
When I was developing the VoIP Fundamentals course, I wanted a demonstration to illustrate the simplicity of the public switched telephone network. After combing through the internet, I came across this ingenious little project. With just a 9V battery, a resistor, a telephone cord, and a […]
Auto Answer is a feature in many VoIP phones that allows the phone to go off-hook the very instant a call is received by the instrument. In this video we’ll look at how this feature is setup and talk about the security vulnerabilities. NIST Report: Link […]