Voltage increaser

The circuit produces high voltage pulses (spikes) of about 40v p-p (when the LED is not
connected), at a frequency of 200kHz. The super-bright LED on the output absorbs the
pulses and uses the energy to produce illumination. The voltage across the LED will be
about 3.6v
The winding to the base is connected so that it turns the transistor ON harder until it is
saturated. At this point the flux cannot increase any more and the transistor starts to
turn off. The collapsing magnetic field in the transformer produces a very high voltage
and that's why we say the transformer operates in FLYBACK mode.
This type of circuit will operate from 10kHz to a few MHz.

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Fleming's left hand rule

Fleming's left hand rule The direction of force produced on a current-carrying cunductor placed in magnetic field can be determined by this rule. as shown in photo hold the thumb,forefinger and middle finger of the left hand mutually at right angles to each other., such that the forefinger is in the direction of current flow in the cunductor; then the thumb indicates the direction of motion of the conductor.

Fleming's right hand rule

Fleming's right hand rule The direction of dynamically induced emf can be identified by this rule.Hold the thumb,forefinger and middle finger of the right hand at the right angles to each other as shown in the photo such that the forefinger is in the direction of the motion of the conductor, then the middle finger indicates the direction of emf induced. i.e.towards the observer or away from the observer.

Disc number calculator

Disc number calculator Normally the disc capacitors does not contains it's original value. but we can calculate it from the number printed on disc. They have three numbers the third number indicates the number of zero to be added, Example = disc no:-104 here the last number = 4 so add four zero to 10 = 100000 give point on three decimal places = 100nf

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