A C Theory

Earlier we discussed that there are various ways to produce electricity. We can produce electricity chemically with a battery. We just learned that electricity can be produced mechanically by a generator. What we did not discuss in detail, though, was the difference between electricity produced by a battery, and electricity produced by a generator.

In the case of a battery, electricity flows in one direction, from positive to negative. Everything is straightforward. In the case of a generator, however, things get a bit more complicated. It is possible to generate electricity by spinning a coil within a magnetic field. The coil is in constant motion within the magnetic field, and thus is transformed into electricity via the magnets. The electricity exits by way of the brushes and slip rings, but it is not exactly like the electricity which is produced by a battery.

If we look at the current leaving the battery, it is constantly moving in the same direction. We call this DIRECT CURRENT . But if we attach a generator instead of a battery in the same circuit, we notice a major change. The meter would swing back and forth from negative to positive. This seems strange until we examine what is going on inside the generator.
As the wire coil rotates, it first passes the north pole of the magnet, producing an electric current flowing in a given direction. As the coil continues in its circular path, it passes the north pole, moving toward the south. As it approaches the south pole, the electric current begins to flow in the OPPOSITE direction from which it was originally moving. It continues to move in this direction until, once again, it approaches the north pole. We say, then that the electrical current is ALTERNATING between positive and negative. We call this type of current ALTERNATING CURRENT .
If we were to plot this swing from positive to negative on a graph, and compare it to the time it takes the motor to turn, we would come up with something like the chart to the left. Notice, that if we begin with the coil positioned directly in the center, between the permanent magnets, the current output is 0.

However as the coil begins to turn, one side of the coil moves toward the north pole. This end of the wire would become positive. At the same time, the other side of the coil moves toward the south pole. This side of the coil becomes negative. At this time, current begins to flow from the positive to the negative. Current continues to flow in this direction and reaches a peak in its cycle. This Maximum amount of current flow is reached when the coil is pointing exactly north and south. We call this the 90 o point, and say that the signal has reached its positive peak. After it passes this point, the voltage begins to drop, but doesn't reach 0 until once again the coil is positioned directly between the permanent magnets. This is the 180 o point.

Now comes the switch up. As the coil continues to turn, the end that was positive now moves toward the south pole of the magnet. Because it is passing by the south pole, this end of the coil swings negative. At the same time, the side of the coil that was negative, is now swinging positive. Thus, the direction of current flow within the wire is switched. The current flow continues in this direction until it again reaches a (this time negative) peak at 270 o . Finally, as the coil approaches its original position, it swings positive until current flow again reaches 0.

Build a Low Noise And Drift Composite Amp Circuit Diagram

How to Build a Low Noise And Drift Composite Amp Circuit Diagram. This circuit offers the best of both worlds. It can be combined with a low input offset voltage and drift without degrading the overall system`s dynamic performance.
Low Noise And Drift Composite Amp Circuit Diagram

Compared to a standalone FET input operational amplifier, the composite amplifier circuit exhibits a 20-fold improvement in voltage offset and drift. In this circuit arrangement, A1 is a highspeed FET input op amp with a closed-loop gain of 100 (the source impedance was arbitrarily chosen to be 100 kfl). A2 is a Super Beta bipolar input op amp. It has good dc characteristics, biFET-level input bias current, and low noise. A2 monitors the voltage at the input of A1 and injects current to Al`s null pins. This forces A1 to have the input properties of a bipolar amplifier while maintaining its bandwidth and low-input-bias-current noise.

High Power Output Amplifier TDA7294

The famous SGS-THOMSON ST Microelectronics has introduced a Hi-Fi DMOS high-power amplifier circuit TDA7294, its sound great taste bile, which due to its internal circuit from input to output are field-effect devices, rounded sound Mild, delicate Rounuan.  However, with its assembly amplifier, only TDA7294 single-output power is only 70 W, BTL access law is 100 W from top to bottom, do not feel that power cushion. The author several tests, used to promote TDA7294-level, direct-drive one to four pairs of high-power transistor parallel, the output of strong currents, the power output of 400 W (mono), and the circuit is simple and no need to debug that can reliably work Basically, the IC has maintained a sound and performance.  Ruzuo The figure below shows, R6 for the feedback resistor, the author of the value in debugging 22 k Î© more appropriate, R6 also decided this circuit gain, the gain value will increase.  Quiescent current depends on the power of R7, R8, when its value…

Full Power Mobile Phone Jammer Circuit Diagram

Full Power Mobile Phone Jammer Circuit Diagram.To day if we are talking about expert Cell phone Jammers we are conversing about this schematic underneath. First off all you should be very very cautious how to use this apparatus. Its completely illegal and so the reason. I post this Circuit is only for educational and testing causes. This type of apparatus is being utilised by security for VIPS, particularly at their limousines to avoid blasting device initiating while the vehicle passes from the goal cell phone-bomb. Off course there are those who use it to make a antic or to make the persons crazy in the rectangle block you are.
The power of the jammer is currently sufficient to do your thing, but certainly you can place a 30W linear power amp at the RF output and impede a much wider locality. So, Be pleasant individual with that and recall that there are people who may need desperately to obtain or make a call and one of them could be you! And if you can't oppose of functioning …