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

MANALI PHOTO

Robotics

http://www.roboticsindia.com is a good forum for Indian users

PIC Microcontroller Links

USEFUL Links for MICROCHIP MICROCONTROLLER

Tiny PIC bootloader
Program a PIC microcontroller -
DIY LifePic Microcontroller ProjectsPractical Microchip PIC projectsuC Hobby »
Accelerometer Based MouseFree Electronic Circuit Design |
Schematic Diagram |
PIC Project |
Microcontroller Project | Homebrew Electronics |
EDA Tool |
Technical Article and Design
http://www.sonsivri.com/forum/index.php
Tiny PIC bootloader

Shibuvarkala college of engineering attingal ceattingal.ac.in

Software Raid debian etch

Install Debian Etch on a Software Raid 1 with SATA Disks

New server, SATA disks, the hardware RAID controller is not really supported. So we decided to use a software RAID 1 for the two disks. Here are the steps to create the RAID:

1. Boot the Debian Etch installer.

2. If the installation comes to "Partition method", use "Manual".

3. In the following menu, scroll to your first disk and hit enter: the partitionier asks you, if you want to create an empty partition table. Say "yes". (Hint: this will erase your existing data, if any.)

• The partitioner is back in the disk overview, scroll one line downwards over the line with "FREE SPACE" and hit enter.


• Create a partition with the size you need, but remember the size and the logical type.


• In the "Partition settings" menu, go to "Use as" and hit enter.


• Change the type to "physical volume for RAID".


• Finish this partition with "Done setting up the partition".


• Create other partitions on the same disk, if you like.


• Now repeat all the steps from the first disk for the second disk.


• After this, you should have at least two disks with the same partition schema and all partitions (beside swap) should be marked for RAID use.


• Now look at the first menu entry in the partitioner menu, there is a new line: "Configure software RAID". Go into this menu.


• Answer the question, if you like to write the changes, with "Yes".


• Now pick "Create MD device".


• Use RAID1 and give the number of active and spare devices (2 and 0 in our case).


• In the following menu, select the same device number on the first and second disk and Continue.


• Repeat this step for every two devices until you are done. Then use "Finish" from the Multidisk configuration options.


• You are back in the partitioner menu and now you see one ore more new partitions named as "Software RAID Device". You can use this partitions like any normal partition and continue installing your system.

See: http://ads.wars-nicht.de/blog/archives/54-Install-Debian-Etch-on-a-Software-Raid-1-with-S-ATA-disks.html

HBS Campus selection

College of engineering Attingal


HBS Campus Selection on 28-09-2007