Make an ISO from files

This will help you to make an iso image of your files and directories

mkisofs -o cd.iso /home/myhome/myfolder

Make iso image of a CD/DVD

This can use for backup your CD/DVD

dd if=/dev/dvd of=dvd.iso # for dvd drives in IDE/ATA
dd if=/dev/cdrom of=cd.iso # for cdrom in IDE/ATA
dd if=/dev/scd0 of=cd.iso # if CD/DVD is scsi/SATA


if your CD/DVD automount , unmount it before running this command that is safer

Recover Ubuntu Grub Bootloader After Windows Wipes it Out

This steps can be done from Windows

• Download software Auto Super Grub Disk

• Double-click auto_super_grub_disk_1.0 icon, install it, and reboot.

• On the next boot, select the UNetbootin-supergrubdisk menu entry; this will launch the Auto Super Grub Disk.

• Do nothing till you see your Grub menu again.

• Next time you boot Windows, click yes when asked to remove UNetbootin-supergrubdisk to remove the Super Grub Disk menu entry.

Disable IPv6 in ubuntu 8.04

Disable IPv6 in ubuntu

Steps
1. sudo gedit /etc/modprobe.d/aliases
2. Find the line: alias net-pf-10 ipv6
3. Edit this to: alias net-pf-10 off
4. Save the file and reboot

Linux Tips Shutdown and Init levels

Linux Commands for Shutdown and Reboot

halt
poweroff
reboot
shutdown

Linux has SEVEN Runlevels( Operating Modes)

init 0 - System Halted

init 1 - Single User Mode

init 2 - Single User Mode with Networking

init 3 - Multi User Mode - Text Mode

init 4 - Not yet Defined

init 5 - Multi User Mode - X Windows

init 6 - Shutdown and Reboot

Simple Transformer design

We are using a very simple method to design transformers

we are using CRGO core, and an equation 7/A yes SEVEN devided by Area

'A ' area of the bobbin in squre inches (L x B).

Straight away You can go to scrap market with a inch scale and calculator . Select a used CRGO core. then start design by measuring the length of middle part of the E core (as Length 'L") and assume a breadth 'B'. If bobbin for your design is not available don'r worry you can make it by using old PCBs or hylam sheet.

We are adopting this method for design of small 230/12-0-12 500 ma transformer to 2 KVA stepup transformers.

7/A is simply derived from transformer equation it is acurate for CRGO

example if bobbin internal ( Hole of bobbin) length 2" and breadth 3.5" area is 7 sq inch then turns per volt is ONE (1 turn/ volt)

Activating the User's public_html Directory with userdir

$ cd /etc/apache2/mods-enabled
$ sudo ln -s ../mods-available/userdir.conf userdir.conf
$ sudo ln -s ../mods-available/userdir.load userdir.load
$ sudo /etc/init.d/apache2 restart

and

make directory at your home folder named public_html as normal user($ mkdir public_html)

ref : http://kimbriggs.com/computers/computer-notes/linux-notes/apache2-public_html-virtual-directories.file

LINUX in Intel G33 Motherboard

I have successfully installed LINUX (Knoppix 5.3, Fedora 9 Kubundu 8.x) in intel G33FB motherboard. In my first attempt I have tried debian etch (with kernel 2.6.18) it will work but graphics, network card and sound card cannot access. Now everything working with kernel 2.6.24 with VT support(E8200) also woking.

PIC Help

PIC16F877 C Programming + LCD screen
All About CircuitsPIC16F877
piclistPIC16F84, PIC16F628 and PIC16F877 application
A PIC frequency counter project written in C using TMR1 and an LCD.

PIC Programming - Getting StartedC for PIC

VISHNUS SCHOOL PHOTO SSNSS School, Varkala