Electronics Engineering

Current, by Ohm's Law, is voltage divided by resistance, so, 18 volts divided by 2 ohms is 9 amperes.

They were first used to communicate. A worker on an active antennae noticed that while it was sending microwaves out, a candy bar melted in his shirt pocket. He then designed a box that would capture and reflect these microwaves to heat up food and liquids. We call it the microwave oven.

Assuming the these resistors are connected in series, the voltage drop across each resists can be calculated simply using V = IR. In a series circuit, the same current must flow through each resistor. So, 2*i + 2*i + 2*i = 6 volts. or i * 6 = 6, or i = 1. So, the voltage drop across all resistors i*r is 2 volts.

Generally, there will be a 12+ volt rail, a 5+ volt rail and often a 3+ volt rail.

Because an ohmmeter works by putting a potential difference (voltage) across a load and measuring the resulting current (the current will be inversely proportionate to the resistance). In a live circuit there is already current flowing through the load so (at best) the reading will be inaccurate, at worst the meter will be damaged.

A circuit that is complete and unbroken with flowing electric current normally has steady supply of voltage with no broken links. Electrical energy flows to light up a bulb or do similar work. Its status is complete, nothing else is needed.

As long as it hasn't been damaged in any way and is taken care of, a microwave can be used for many years - my own parents are using both a standard microwave and a combination microwave/conventional oven that they've owned since 1982.

The main health hazards with microwaves are to people with pacemakers and similar type medical implants - not all microwaves are taken care of the same.

AV stands for Audio Visual, i.e. engineering systems in sound or video production, encompassing TVs, monitors, receivers, amplifiers, soundbars and so on. All of those components requires electronic design to create in the first place, and also to some extent some knowledge of electronics can be a help in building AV systems that are constructed from many discrete components.

Oscillator is a generic word for any circuit that produces an alternative signal.

The shape of the signal, its stability and its output impedance are not considered in this case.

"Local oscillator" is one specific type of oscillator used in radio receiver for the purpose of frequency conversion. the input Radio Frequency( RF ) signal is "mixed" with the local oscillator signal and the subtraction of two frequencies is obtained at the output.

"Mixing" in this context means: "multiplication"\

In some other context in electronics (specially audio) mixing means "adding"

the mathematical operation for local oscillator is F out=Fin - F loc.osc.

The output of the mixing operation can also be Fin+F loc.Osc. But this higher frequency is usually filtered out.

The local oscillator needs to be a pure sine wave with a very good frequency stability and usually very stable output voltage.

Recently very good "synthesizers" are introduced in the market that permit generation "programmable local oscillation"

Oscillators are used in a lot of applications. The fact that they oscillate, meaning switch between a zero and positive orbetween a negative-positive value in a repetitive way, makes them useful as a time base.

As time base, they can be used to activate processes that are time-dependent, eg. a computer: has an internal clock (several, to be more corect) that is driven by a kind af an oscillator.

Most of these oscillators to drive time-based electronics are digital, meaning the oscillation is a square wave between 0volts and some positive value (eg. 3.3V or 5V)

Another common use of oscillators is for data communication: a waveform of a certain frequency is generated by an oscillator, and information is superponed on this electromagnetic wave.

Other appliances that use waves generated by oscillators are like microwave ovens, radar, sybthesizer, clock radio, modem (both digital and analog types), sirens, Christmas lights, ...

You can be sure, if it has anything complicated electronic in it, it almost certainly has an oscillator build in.

see also http://en.wikipedia.org/wiki/Oscillation

3dB of gain rolloff is a linear reduction of gain by a factor of 2. That makes it a good reference point.

NO dont do it if you devalue a capacitors voltage parameter what will it do when it is face to face with 20V ? The voltage will destroy the thing. Remember it is OK for you to use a higher voltage parameter for a capacitor but never lower

No. There are losses involved with each stage of the conversion, from DC to AC, and from AC back to DC. The battery running this would gradually discharge. Any other result would constitute a perpetual motion machine which, in this imperfect world, is impossible.

I have not seen any reports on Ancestry.com or other genealogy sites that give a death date for him, and it is certainly possible he is still alive; having been born in November 1935, he would be 81 years old in 2016.

The 74LS00 is a logic NAND gate with normal logic level inputs. This means that the inputs has a low range below 0.8V, unrecognised range and a high range above 2V. At any time a input signal crosses those levels, a change in state can be expected. Applicable to the LS family, they have a floating input that means it is uncertain the state of logic level if no input is connected. Therefore never assume that since the input is not connected that the circuit will assume a zero, it can be either zero or one.

The 74LS132 is also a NAND gate logic function. But different to the Logic level input it uses what we call a Schmitt trigger input to improve noise immunity in a circuit. In simple terms; it's really nothing more than a comparator input. But the Schmitt trigger also have a hysteresis, which help to eliminate the affect what noise have on the circuit.

On a more technical note

Each circuit contains a 2-input Schmitt trigger followed by a Darlington level

shifter and a phase splitter driving a TTL totem pole output. The totem pole is basically a push-pull output stage constructed with two p-n-p transistors and a diode on the output.

The comparator function would mean that there is a particular threshold level on the input and if the input voltage pass the particular level, the output or intermediate state of the function will change state. In the case of multiple logic inputs the change of input state does not necessarily mean a change in output state and therefore I will refer to an intermediate area inside the function related to the input state.

The hysteresis create a high and low trigger points. This cause the input to at least pass the high trigger point of about 1.6V before the intermediate state will change or drop below the 0.9V before the intermediate state change back again. Therefore the practical unit will not have one particular level to change state but these two fixed trigger points must be used.

It sounds like it complicates matters but it really helps to handle input noise signals which makes the Schmitt trigger a handy device. Making it a good device for signal conditioning of logic signals in some applications.

Also take note that the high and low hysteresis trigger points may vary with supply voltage. In fact I do not recommend it as standard practice to use a Schmitt trigger to evaluate analogue levels, some engineers may differ but I would rather refer to a real comparator circuit design where you have more control over precision, trigger points and reference levels. But may be considered for logic inputs from sensors or conditioning of logic signals

Some circuits may also employ Schmitt trigger devices for oscillators and contact debouncing

Logic Gates are electronic building blocks of a digital system.

Their physical manifestation may take any form, but essentially a logic gate consists of a collection of binary digits and a set of rules where such digits are combined to give a resulting set of binary digits.

The rules that are implemented by logic gate are of the fundamental Boolean Algebraic Operations.

Logic gates may be coupled together so that digital input to a system produces a predetermined digital output. It is a logical set of rules. The concept of digital information flowing into a system through an electronic pathway coveys a perception that gave someone the idea of a gate when this was named long ago.

To produce a 3-input OR gate when only 2-input OR gates are available: Use 3 OR gates Inputs to Gate A are input 1 and input 2 Input to Gate B is input 3 (if 2 inputs are necessary, include input 3 and FALSE) Inputs to Gate C are outputs from Gate 1 and Gate 2 === If input 1 OR 2 is TRUE, output of Gate A will be TRUE. If input 3 is TRUE, output of Gate B will be TRUE. If output of Gate A OR Gate B is TRUE, output from Gate C will be TRUE. That is if one ore more of Inputs 1, 2 or 3 is TRUE, the result will be TRUE. Otherwise, output of Gate C will be FALSE.

the amount of potential to forward bias it

Measures current by magnetic field induced into the clamp. You need to clamp a single conductor. For example you couldn't just clamp a lamp cord since it has two conductors and the current is going in opposite directions and the fields cancel each other out.

Do you mean :- how to get full adders by using half-adders?

For this question refer following answer -

A full-adder can be obtained by combining two half-adders and one or gate.

Details on full-adder and half-adder can be referenced from following link

http://www.fullchipdesign.com/fulladder.htm

Cathode ray tube amusement device was created in 1947.

Transistors were shortly thereafter replaced by integrated circuits, which further minimized size and lessened power requirements.

FM transmitter : In this case the frequency of a carrier signal is modulated/altered in accordance with that of frequency of modulating signal.

TYPES OF FM TRANSMITTER:

1> directly modulated FM transmitter.

2>indirectly modulated FM transmitter.

an FM transmitter is a portable device that plugs into the headphone jack or proprietary output port of a portable audio or video device, such as a portable media player, CD player, or satellite radio system. The sound is then broadcast through the transmitter, and plays through an FM broadcast band frequency. Purposes for an FM transmitter include playing music from a device through a car stereo, or any radio.

Yes, most DMM are ''average responding", giving accurate rms reading if the ac voltage signal is a pure sine wave. They measure the average of the absolute value of ac voltage and are calibrated so that reading are corrected to that of the rms value of a sine wave.Error occur if harmonic are present.