Archive for the ‘Miscellaneous’ Category.
Well, there is an old saying:“There’s no such thing as a free lunch.” After yesterday’s server upgrade, everything worked pretty well till sometime late this afternoon. Continue reading ‘Weekend Server Upgrade – Update’ »
I have finally got around to upgrade my web server. The server I have been using was an old Pentium III about 10 years old. It had been serving my website quite well over the years till recently. Continue reading ‘Weekend Server Upgrade’ »
This is what I ran into for the first time: I was flashing the chip the other day and after many successful runs I encountered the following infamous avrdude error: Continue reading ‘The Case For Using Parallel Programmer’ »
The Google PAC-MAN logo is actually a live game! Continue reading ‘Google PAC-MAN’ »
Using PC’s parallel port is a convenient way to control a stepper motor. For unipolar stepper motors, up to two motors can be controlled with the 8bit data line. Continue reading ‘A Parallel Port Stepper Motor Driver With Discrete Components’ »
Using DTR (data terminal ready) and RTS (request to send) pins of a PC serial port (RS-232) without actually using the serial data pins, we can interface at least two relay devices with a computer. Windmeadow Labs has an excellent article on how to achieve this using a bipolar transistor (BJT). Here I will show you a similar relay control circuit built using an opto-isolator and a MOSFET. Continue reading ‘An Isolated MOSFET Serial Port Relay Controller’ »
One of my older CRT TVs does not have a built-in degauss button and after sitting in the corner of the basement for a couple of years, it somehow got magnetized pretty badly. The top two-thirds became totally disclorored with the “rainbow” effect. Continue reading ‘Building a Degaussing Coil’ »
A touch sensitive on/off switch can be made with a single MOSFET. The following schematics illustrate such a switch using only a power MOSFET (IRFZ22). Continue reading ‘The Simplest MOSFET On/Off Switch’ »
When Google Chrome beta for Windows was first released last September, I tested it briefly on a Windows XP box and was quite impressed by its speed and simplistic user interface. Continue reading ‘My First Few Days With Chrome for Linux Beta’ »
Hall effect sensors can be found in many common household gadgets. Most brushless DC motors for instance, like those used in computer cooling fans, contain Hall effect sensors in the driving circuits. Continue reading ‘A Hall Effect Magnetic Field Polarity Detector’ »
A palindromic prime (palprime) is a prime number that is also palindromic. So out of curiosity I wrote a simple program a few days ago that can find the palindromic numbers within a given range. Here is the code in C++: Continue reading ‘A Simple Program for Finding Palindromic Prime Numbers’ »
Many of you may still remember the capacitor plague that caused massive motherboard failures back in the early 2000s. While the practice of using cheap and unreliable electrolytic capacitors in computer components has largely died down nowadays, it seems that the issue has cropped up elsewhere. Continue reading ‘CFL Capacitor Problem’ »