Windows Registry

One of the most important programs of a windows operating system (XP, 2000, NT, 98, 95) is the Windows Registry that is also the brain of the operating system. When any software is installed or modified or accessed the registry values are changed to reflect any changes in user or the software settings.

The Windows registry is also the main reason for viruses. Modifying values in registry to disrupt programs is very easy by understanding basics of Windows registry. There is more than one method to modify the registry.

The most simplest way to modify the registry is by a simple method:

1. Understand the registry properly including the keys and values. You can get information at this site: http://support.microsoft.com/kb/256986
2. Write the change keys into a notepad file and save it as FileName.reg
3. Write a batch file containing list of commands to open the *.reg file
4. Write autorun for the batch file to run during startup of windows

Voila! You have successfully modified registry.

Other methods include visual basic scripting (vbs), java scripting (js) or C programs.

In my next post I will show a simple method to modify registry using the first method (reg bat method)

CRO Games

My friend and I always look for a chance to rush to the Electronics Lab during free sessions to play around with Circuits and the CRO. Our ultimate aim is to display all the English alphabets on the CRO. While playing with the clamper circuit we came across few output waveforms, one of which looks like a rope lasso.

new project idea

With the end of my end-sems, my mind is now completely free to plan out my next project. 2-1 was very exciting and provided lots of basics of electronics for me to apply in later stages of my career. One important field was Logic Designing that thought me the basics of binary. Armed with this tool, an engineer can design anything that suits his needs.

Few days ago I noticed a lack of security in residential buildings especially apartments. I wrote myself a problem statement:
Build a security device that protects an apartment and is easy to use. The device should be built according to the needs of a family of four.

I came up with this problem statement with my house and family as the test area. The door of house consists of an auto-lock feature, on closing, that can only be opened, from the inside manually or from the outside using a key. The system is made by Godrej.

I have started analyzing the problem statement. More details in next post.

the cockroach controlled bot

I found this video on youtube. Its an amazing adaptation for controlling a robot. Its not very difficult to build the robot but the idea is too good. Its got a very simple mouse rollerball mechanism consisting of sensors. One thing, I dunno how they managed to keep the roachy on the robot? Any idea?

555 IC timer

The 555 IC timer is an integrated circuit. I used an ST (SGS Thompson Microelectronics) NE555 timer IC to build a multivibrator. A multivibrator is a circuit used for two state systems. I built my circuit to control a motor polarity. But it did not work. This is the first time I experimented with a 555 timer. I used a digital circuits reference book and studied multivibrators. I tried building a astable multivibrator. It switches from off to on by itself without any external trigger. Find more about multivibrators in my next post.

switched-mode power supply

We needed to test the motor to which I had soldered wires. My old PC had a working SMPS(switched-mode power supply). So I pulled it out of the PC and used the floppy power cable as the source. I connected two wires each into the floppy red and yellow power cable. Then I fixed these wires to the breadboard. I took the motor’s wires and completed the circuit and switched on the power supply. The motor was succesfully working, also confirming that I could use the unregulated power supply as my source.

After this my friend and I got on to testing LEDs and switches using the SMPS. We connected each component and tested it. We are planning to make a Regulated Power Supply using C program and parallel port.

gujarati gulli

17°23'9"N, 78°29'0"E is its location and its one of the most important locations for the Engineers in Hyderabad. Located along the Koti Women's Hostel road, Gujarati Gulli consists of all the electronic stores with almost everything from spare parts to basic circuits to CRTs.

I was on a hunt for various sensors and motors. I was in almost every store and found out about the costs of most spare parts. Roland Electronics is the best store with everything I needed for my project available here. Out of the things I bought were IR sensors, 555 IC timers, LEDs (red and green), shafts and a 12V DC motor. All of these costed me less than Rs. 150. There is still more stuff to buy for my project and these are yet to be listed.