Fly Back Converter - part 1

The Flyback converter is a DC to DC converter with a galvanic isolation between the input and the output(s). Galvanic isolation is the principle of isolating functional sections of electric systems so that charge-carrying particles cannot move from one section to another, i.e. there is no electrical current flowing directly from one section to the next. Energy and/or information can still be exchanged between the sections by other means, however, such as by capacitance, inductance, electromagnetic waves, or mechanical means.

Demodulation of FM

Frequency modulated wave is demodulated using NE565, a PLL IC. The FM wave is fed as input. The phase locked loop is locked at the desired frequency thereby producing the desired message signal waveform. This IC produces most linear demodulated message signal. Because of its linearity it can lock and track the input signals over a high bandwidth. The message signal is then amplified to get the output, which is the actual modulating message signal.

Generation of FM

Frequency modulated wave is generated by using function generator IC. The carrier frequency varies according to the changes in the message signal’s instantaneous voltage. The carrier wave is generated internally by the function generator IC. The IC used is XR2206. This IC is a low frequency high gain IC. It would be enough for us to give the message signal alone as input to it. It can generate up to a frequency of 700 kHz. The modulated wave is then passed through the buffer and thus FM wave is generated.

Demodulation of AM Wave

The demodulation of AM wave is done by using envelope detector. It is the most basic method of demodulation. In this method, the changes in the amplitude of the carrier is tracked by the envelope detector and thereby recovering the message signal. The output is then amplified to get proper message signal. The envelope detector uses power diode OA79 and a capacitor to track the changes. The power diode is used because the input AM signal is of very low amplitude. If we use ordinary diode, it will not detect as it is well below its threshold level. The output wave is the actual modulating message signal.

Generation of AM Wave

AM wave is generated by using multiplier IC (product modulator). The input message signal is multiplied with the carrier signal to produce a double side band suppressed carrier wave. Then carrier is injected to produce standard AM wave. The IC used is AD633. It is a low cost analog multiplier IC used to produce standard AM wave. The inputs are message signal, which has to be modulated and a carrier signal. The output wave is an under modulated standard AM wave.

Ilayaraja the best

Ilayaraja is one of the most prolific the best music directors in the world. He has not only made Tamil Nadu proud, but also has made India proud. He has composed over 5000 songs in almost all the languages in India. His legacy still continues. He has two sons and a daughter.

External Hard disk

Some months back my friend bought an external hard disk which has a capacity of 80gb. This hard disk turned out to be so useful to us. We used to copy all the movies and other stuff that we get and exchange it among us. It is so easy to use. Even good games can be copied into it.

Sam Anderson

Are you wondering who the owner of that name would be? Are you contemplating of a Hollywood star as the name suggests? You are absolutely wrong. He is none other than the rising superstar of the Tamil cinema. He has a great fan following in India. His movie has an Oscar by a whisker.

P.S: Believe them at your own risk!

No country for Old Men

When the movie won lots of Oscars and other accolades, I was so eager to watch the movie. Since the movie did not release at my place, I rented a DVD and watched it. The movie was awesome and spectacularly directed. Three cheers for the Coen brothers. This movie is must watch. Watch it right away.

Director Samy exonerated from his ban

Director Samy, who directed Mirugam and Uyir was banned few months back for slapping the heroine of the film, Padmapriya. He was banned for 2 years. But now he was acquitted from his ban and now he can resume his career in the movie industry. Padmapriya would be very angry after hearing this.