Electronics Engineering

In an Information Technology (IT) context, the signals that we want to amplify most often nowadays are carried by microwaves, light and 'regular electronics'. From the question, 'regular electronics' is presumed with frequencies in the radio to lower microwave range. This range includes electronic digital computers and most domestic electronics.

To amplify a signal one needs to switch or otherwise control a large current or voltage or 'other' with a small current or voltage or 'other'. Typically, human ingenuity has found many ways to do that.

Therefore, the answer is that semiconductors are not required for amplification of electrical signals. Conductors (in one way or another, though we should define our terms carefully) can often be used. The underlying truth is there are usually many factors that influence our choices of technologies. Obvious ones are that the technologies are very cheap, easy to produce, can be miniaturised, can work at high speed, use low power, are reliable and so on. Semiconductors meet all those requirements very well.

If you would like to consider an alternative, consider a thermionic valve such as the triode. The thermionic valves were the first widely-used electrical amplification devices. They are relatively simple to understand and they work extremely well. However, they are physically large, they generate a lot of heat, they cannot be miniaturised in any significant way, and they tend to have a short lifetime (compared with a transistor).

A limitation of semiconductors is that they break down if you use very high voltages or very large currents.

Consequently, thermionic valves are still used today for very high voltage and very high power applications.

If we assume that amplifiers are imperfect we might ask about the imperfections. Many audiophiles (lovers of music) insist that thermionic valve amplifiers sound much better than semiconductor amplifiers. Therefore, many guitar amplifiers and the top-of-the-range HiFi amplifiers tend to use thermionic valves.

If you would like a second example, consider any type of relay. It meets the requirement for an amplifier, though it is limited to the amplification of digital signals only.

Thermionic valves and many of the types of relays could be described as being made of conductors only. We use semiconductors (most of the time) for the amplification of electrical signals because they are very cheap, easy to produce, can be mass-produced and miniaturised, can work at relatively high speeds, use low power, are reliable and so on.

DonB

Ohms law states that

V = I * R

I = V/R

R = V/I

P = I*V

Where V = Voltage, I=Current, R = Resistance and P = Power or Watt Watt is the amount of electricity flowing through a line which is (Voltage times Current in (Amperage) = Power or watts) To find the power dissipated by a resistor of 1000 ohms, we first find the current I. The voltage is given as 200volts. Therefore I = V/R = 200/1000 = 0.2Amps We said Power or Watt = I*V Therefore the Power or watts dissipated by a resistor of 1000 ohms will be P=I*V = 200*0.2 = 40 Watts

Yes, most MCU's can not multi task it can run only one program at a time, so if you run a stepperor servo motor from one MCU it will slow down the whole program so, if you have send the command from the main MCU to the other one that is controlling the stepper or servo the main MCU can go on doing other things while the stepper MCU can take its time taking the stepper motor thru its paces If you have to run more than one stepper and using only one MCU, the MCU will have to drive the one stepper with one pulse and then the next stepper, you don't need a large MCU to drive a stepper only 4 bits is needed a 8 pin PIC like the PIC12F675 is all you need, GP0 to GP3 can drive the stepper while the chip can receive commands on GP5 that is a input pin only ,then you still have GP4 spare to drive a LED or a relay or you can use it as a DTR to send an interrupt to the main MCU and tell it that its done with the last command and ready for the next.

A string of commands can be received by the 12F675 in serie on one pin and be stored in onboard EEPROM for use as needed

Both, E=Es + Ev = cB therefore, B= Es/c + Ev/c = Bs + Bv.

The electric and magnetic fields are quaternion fields consisting of a scalar field and a vector field.

Contemporary Physics has not realized this yet. Correct Relativity Theory is a manifestation of quaternion fields, consisting of a scalar field and three vector fields. This shows up in the Energy Momentum four vector, E= Es +cmV.

Actually the Lorentz Force is both scalar and vector: F=qvB = - qv.B + qvxB

it makes no sense consider only qvxB and to ignore qv.B.

The clap switch works with the use of an impulse response of a transfer function. It makes use of a sound analyzer input and interface with a digital signal processor and FFTs.

Diac

If your test meter is an analog type of meter there should be a zeroing screw on the meter face that is connected to the needle movement. Turn this screw to zero the meter. If the meter is a digital there should be a potentiometer, probably in the battery compartment that can be used to zero the display.

Programmable Logic Controllers are automated robots which carry out tasks in the assembly lines of factories. The most common use of PLC's can be found in the car manufacturing industry. The industry is growing at a great pace, owing to the demand of technology and as a tool for saving unnecessary costs.

The meter ( as refered to a conventional moving coil analog pointer type ) basically operates on a Direct Current ( DC ) passing in its coils. Hence the meter inherently has a polarity of operation i.e the positive & negative inputs of the meter must be connected appropriately with the corresponding positive & negative potentials in the circuit being measured , so that the meter deflection is in the correct direction of the measuring scale ( typically clockwise movement )

Bsis Voltage & current measurement scales are linear , while resistance ohmic measurement scales are generally non linear.

Incorrect polarity of connection will result in the meter deflecting in the opposite direction & usually will not damage the meter unless an inappropriate measuring range was selected.

Whenever the magnitude of measured voltage or current is not known approximately beforehand, the best precaution is to use the highest range on the meter & stepping down the range if the deflection is too low for a good reading.This will prevent damage to the meter due to overload deflection which generally will damgage the delicate moving parts of the meter, which results in a total writeoff.

For measuring voltages , the meter configuration as a voltmeter is used, where a series voltage dropping high value resistor appropriate to the range of voltage being measured is incorporated into the meter itself. The voltmeter is always connected across the points where the measurement is required. Hence no alteration of circuit is required for this measurement.

For measuirng current, a low value resistor across the coils of the meter is incorporated appropriate to the range value of currents being measured, as a shunt to divert currents larger than what the basic meter can handle. It is necessary to break the circuit at a convinient point where the measurement is required and the meter inserted into the circuit. Hence an alteration of circuit is required for this measurement.

When a meter is configured to measure resistance , a low voltage battery source with appropriate circuitry is incorporated into the meter itself to read the resistance value directly in ohms.

Modern digital meters generally have bipolar measurement capabilities, in which the polarity of measurement is indicated. Here only the moving coil meter is replaced by a analog to digital convertor chip which directly displays the value on the digital readout. Otherwise the same measurement principles apply.

An attenuator is the opposite of an amplifier. An attenuator is used for reducing the power of a signal. An attenuator is able to do this without modifying the waveform of the signal.

On a standby generator 100 percent of the power drops before the generator will start.

Yes, it certainly is appropriate to mention those things together,

as the principles of their interaction are so inexorably intertwined.

there are many such as:

Wind energy

Solar energy

coal

oil

Natural Gas

Hydroelectric Power

Nuclear Power

Geothermal

I could go on, but it will be a VERY long list.

According to CoR Lab at the University of Bielefield in Germany, there are approximately 60 ASIMOs, most of them at Honda Research in Japan. They cannot be purchased and there is no estimate on a dollar value to each unit.

Ripple, in DC power supplies, is technically unitless. Ripple voltage is specified in Volts/Volt, or a percentage. For example, a 12VDC power supply with 120mV (pk-pk) of ripple voltage is (0.12/12) = 1% ripple voltage.

they should possess low inductance as the sparking will be less during the time of opening

The lowest priority interrupt in the 8085 microprocessor is INTR, unless you also consider the software interrupts, RST 0 through RST 7, which are even lower.

This is something that your utility company needs to know about. One reason is you probably are not getting enough amperage to service your house. If the incomming voltage is abnormally low you need to have this checked out. About the question, it would depend if your amperage increased. You pay by the kilowatt hour. Volts X Amps = Watts Chances are the low voltage is a symptom of the true cause of your high electricity bill, not the cause itself. Driving your appliances at a lower voltage (except for modern devices with switching powersupplies) will cause them to draw less power, and therefore cause a lower bill. (Now, before you get any ideas, this will not work for switching powersupplies. That means computers, TVs, etc. It is bad for motorized appliances as they may not start in a undervoltage situation. Lights will not work as well, etc. Also, whatever you jury-rig into your feed will have to dissipate the power equal to the product of voltage across it and the current through it. So, you will not lower your bill at all as the energy not being dissipated by your appliances will be dissipated by whatever you stuck in the feed. Anyways, back to the question at hand: ) If you have a low voltage problem, either you are overloading your supply, you have a bad connection, or a short. Checking for a short is easy: * Turn off everything. * Unplug all everything and turn off all lamps. * Shut off all the breakers, including the main. * See if your meter is turning. If it is, call the electric company. * Turn on the main breaker. * See if your meter is turning. If it is, call an electrician. Don't DIY on the main feed. Save it for the branch circuits. * Turn on the breakers one by one and check the meter. If it starts turning, check that absolutely everything is off on that circuit. If everything is, you know have a general idea of where energy is leaking. Call an electrician or happy hunting. * If you can turn on all the breakers and the meter does not turn, you do not have a short in your home's wiring. Either you have a defective appliance or you use a lot of energy. If you don't have a short, the undervoltage problem is either a overloaded supply or failing wiring devices. Call an electrician, this is a serious fire hazard (something is dissipating that energy into heat, somewhere). They will have the tools to quickly track it down and fix it for you.

There are a number of steps that you can take to prevent this distortion from occuring. But in order for you to know what to do, you should specify a few things, first:

a) Do you have an antenna signal amplifier?

b) Is it just one or two channels being affected, or is it all of your channels being affected?

c) What channels and ranges does your antenna receive?

d) What sort of distortion is it? Are adjacent channels bleeding into this one? Are there horizontal streaks and lines appearing? Or is it just an entire screen filled with noise? If all of your channels are affected or wiped out and you have an antenna signal amplifier, it may be that your amplifier's transmitted signal is too strong.

Also, it could be interference from an adjacent channel or the FM band. In this case, you may need a bandpass or a bandstop filter.

To get a bandpass or bandstop filter, you should probably turn to an electronics provider like Tin Lee Electronics (www.tinlee.com). You can also contact them about your problem and they should be able to help you solve it. In any case, if you could specify the above information, it would be much easier to find an answer to your problem.

Tungsten. Gold or uranium may also be used but it is usually tungsten.

The postal codes for the Northern Region province of Gauteng in South Africa range from 0001-0299. The South African Post office offers a post code search tool and PDF listing every number on its website.

The only different is one has a needle, the other digital numbers-same as with analog and digital watches.

2, 4, 6, 8, 10 it depends on the amount of modulation. 100%
1 on each side, 200% 2 sidebands on each side.

dual kill of ennd