Q .Find Voltage across diode

     Diode equation is : i=10^-15(e^30v -1)

Solution:

We do multiple source transforms and then write the nodal equation as

0.0001v+ 10^-15(e^30v -1) -0.001=0

Solving by Newton Rapson Method we get

Numerator = (0.0001*x)+ 10.^(-15)*(exp(30*x)-1) -0.001

Denominator =0.0001 + 30*(10.^(-15)*(exp(30*x)).          

So solution after a number of iterations is : v=  0.9178

Number of Iterations = 8

Code:

x = 0;
temp = 1;
count = 0;
while x~= temp
    x = temp;
    num = (0.0001*x)+ 10.^(-15)*(exp(30*x)-1) -0.001;
    deno = 0.0001 + 30*(10.^(-15)*(exp(30*x)));
    temp = x - (num/deno);
    count = count+1;
    p(count) = x;
end  
plot(p);
title('convergence after multiple iterations');
fprintf('Number. of Iterations = '); disp(count);

fprintf('Answer =');disp(x);

Plot:

Reference: 

http://www.ecircuitcenter.com/SpiceTopics/Non-Linear%20Analysis/Non-Linear%20Analysis.htm

By
Aalap Khanolkar-  2016110027
Rahul Kelaskar* 2016110026

Microphone Magic

IT DOESN’T RECORD YOUR SOUND, IT RECORDS YOUR SOUL!

We are surrounded by different types of sounds. Some of them are audible to us while some are not. Microphones and speakers have played an important role in perception of sound in both sound reinforcement and audio production.

A microphone commonly known as mic or mike is a transducer that converts vibrational energy into electrical signals. Microphones have wide applications in music, public address systems, telephones, hearing aids, etc. Several microphones have different methods to convert air pressure to sound signals. Dynamic, condensers are few of common types.

A concept of microphone was first implemented by using acoustic megaphones when human voice was insufficient to address huge groups of people. Graham Bell’s telephone also used a microphone. Edison is awarded the patent of developing world’s first microphone which was a carbon microphone. During latter half of 20^th centuries SM57 and SM58 are still most widely used microphones in the world.

Basic microphone consists of sensitive plate. Sound is first converted to mechanical motion by displacement. Wireless Microphones contain a radio transmitter.

Microphones can be characterised as:

1. Condenser Microphones:
A condenser microphone capsule with a gold sputtered mylar diaphragm.
The backplate consists of solid brass with a hole pattern that must be drilled with extreme precision for consistent sound. this is the frequency responce of condensor microphone.They require external power.
 

2. Dynamic Microphones
Dynamic microphones are versatile and ideal for general-purpose use. They use a simple design with few moving parts. They are relatively sturdy and resilient to rough handling. They are also better suited to handling high volume levels, such as from certain musical instruments or amplifiers. They have no internal amplifier and do not require batteries or external power.
 

3. Ribbon Microphones:
Ribbon microphone uses a thin alluminium, durallium or nanofilm of electrically conductive ribbon placed between the poles of a magnet to produce a voltage by electromagnetic induction.

 

4. Carbon Microphones:
The carbon microphone, also known as carbon button microphone, button microphone, or carbon transmitter, is a type of microphone, a transducer that converts sound to an electrical audio signal. It consists of two metal plates separated by granules of carbon.
 

Different microphones differ from each other from polar patterns, frequency response,Dynamic ranges. etc.

There are many micking techniques to achive better quality of sound.

There are a number of different methods for stereo. Three of the most popular are the spaced pair (A/B), the coincident or near-coincident pair (X-Y configuration), and the md-side (M-S) technique.

Spaced Pair Technique
The spaced pair (A/B) technique uses two cardioid or omni directional microphones spaced 3 to 10 feet apart from each other panned in left/right configuration to capture the stereo image of an ensemble or instrument. 

X-Y Technique
The X-Y technique uses two cardioid microphones of the same type and manufacture with the two mic capsules placed either as close as possible (coincident) or within 12 inches of each other (near-coincident) and facing each other at an angle ranging from 90 -to135 degrees, depending on the size of the sound source and the particular sound desired.  

Mid-Side Technique
The M-S or mid-side stereo technique involves a cardioid mic element and a bi-directional mic element, usually housed in a single case, mounted in a coincident arrangement

Thus, microphones magically convert audio signals and helps to connect souls. Hence it is rightly said “IT DOESN’T RECORD YOUR SOUND, IT RECORDS YOUR SOUL!”