Quiz Buzzer v2

Nov 20, 2014

After being stuck in development hell for a few years now, version 2 of the Quiz Buzzer is at last here. The final iteration of polishing/testing/reengineering has been done, and the buzzer is finally complete. The new buzzer is one single all in one board with the LED seven segment display, the display driver circuitry and the controller circuitry all integrated into one monolithic PCB. Finally, from prototype to usable product…

Tags: electronics, project

Over the Arabian Sea

Feb 26, 2013

…here at last, we have these spectacular images - images that rained down from the sky! It's true that they are still imperfect, and rather noisy (a situation that I intend to fix soon). But, anyway, here they be recorded, before the miracle of the moment passes away…

Tags: radio, satellite, weather, electronics, project

RC Phase Shift Oscillator - Oscillation Criteria

Jan 20, 2013

Maxima is a computer algebra system. That's kinda like a calculator that can do algebra instead of just numerical calculations! I let Maxima cut through all the algebra of the RC phase shift network. Lo and behold, here we have the results, achieved almost painlessly!

Tags: electronics, maxima

Design of LC Oscillators - Capacitive Overload

Jun 30, 2012

If the frequency was high enough, the capacitor in the tank would draw too much current from the output of the amplifier, and the amplifier would overload killing its gain and bringing the whole system down…

Tags: electronics

How do oscillators start up?

May 12, 2012

If you are into oscillator theory, you probably know that oscillations in an oscillator build up exponentially before hitting power supply saturation and stabilizing. Well, at least that is what the textbooks and the equations claim. But, have you ever seen it? :-)

Tags: electronics

Resistance Measurement — Common Mistakes

Apr 29, 2012

A few common and silly mistakes people might make when they are learning to use a multimeter to measure resistances…

Tags: electronics

Quiz Buzzer

Mar 17, 2012

This is a quiz buzzer system supporting a maximum of 8 teams. It uses an ATMega8 microcontroller unit to continuously read the state of the buzzer switches, find which team pressed the buzzer first, and display the appropriate number in the seven segment display.

Tags: electronics, project

Resistor Color Codes Script

Mar 17, 2012

I just decided to write a Python script to convert resistor color codes to resistance values. Later, I also wrote a script to do the reverse - namely to find the color code of a given resistor.

Tags: electronics, python, software, project

Series Regulated Power Supply

Mar 17, 2012

This is a series regulated power supply that provides an output voltage of about 5.3 V and a maximum current of almost 500 mA.

Tags: electronics