Electronics Engineering

When a tri-state logic device is in the third or high-impedance state, it means that it is effectively disconnected from the circuit. This state allows multiple devices to share a common bus without interfering with each other. It is commonly used in buses and multiplexers to prevent conflicts and allow for efficient communication.

A transistor can electronically switch the output by controlling the flow of current between its two terminals, called the collector and emitter. It has a third terminal, called the base, which acts as a control input. When a small current is applied to the base terminal, it influences the flow of current between the collector and emitter terminals, effectively turning the transistor "on" or "off" and allowing it to change the output state.

current depends exponentially on voltage:

diode equation (approx.)

Idiode=k (exp (Vdiode/Vth)-1)

k=constant (saturation current, something like a femto ampère)

Vth=KT/q => 25.8 mV @ T=300 K, Vth is thermal voltage

K=Boltzmann's constant

T=junction temperature (Kelvin)

q=electron charge

http://hamradio.lakki.iki.fi/new/Datasheets/transistor_pinouts/case-14.gif

Picture in context can be found here:

http:/hamradio.lakki.iki.fi/new/Datasheets/transistor_pinouts

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The maximum voltage which can apply When diode in reverse bias..if it is exceed that voltage the diode may get damage.

Voltage is what is measured in volts. This is the electric potential difference between two places. The electric current is also measured so as to ascertain the voltage.

A capacitor is an electrical or elctronic semi conductive material which have the ability to store electrical charge and discharge when needed, and also used for timing a circuit and finally used for filtering in a circuit.

A capacitor is made up of two plates seperated by die-electric strength or material.

Thanks

my receiver is lock i want to open i dont know how can i open because i forget 4diget lock nomber what is the master code thanks

Polyester film capacitors are film capacitors using a dielectric made of the thermoplastic polar polymer material polyethylene terephthalate (PET).

We're JYH HSU(JEC) Electronics Ltd (or Dongguan Zhixu Electronic Co., Ltd.), an electronic components manufacturer. You may google search "JYH HSU" to find our official website.

It is because a mobile is operated on a battery with low power and therefore it sends signals on low(uplink) frequencies whereas a base station is driven by high power and can easily send signals on high(downlink) frequencies. This can be verified by Friis equation which says Transmitted power and Transmitted frequency are directly proportional.

A voltage transformer takes a primary voltage and steps it down to a smaller secondary voltage. This type of transformer will attempt to keep the secondary voltage at a specific ratio of the primary voltage. If you short it, massive current flow in the secondary is required to do this.

For a similar reason a CT should never be open circuited - because it attempts to push a specific ratio of primary current through the secondary. If you open circuit the secondary, it takes a massive voltage on the secondary to accomplish this.

Two diodes, whether or not discreet, cannot work together as a transistor. The diodes and transistor have different profiles to optimize them for their specific functions

There are more than two conditions that can make a thyristor conduct, but the general (functional) ones are:

1) positive voltage form anode to cathode, and

2) a positive voltage on the trigger input (referenced to the cathode) for a standard polarity thyristor.

Other conditions can be:

A) Anode-Cathode Voltage exceeding thyristor witholding voltage.

B) Overtemperature of the thyristor chip

C) Faulty thyristor (can be caused by overloads)

it is used to supply power to motherboard and other peripherals

Flux is used to keep metals from oxidizing. Solder will not bond well with copper-oxides which are formed when copper is exposed to high temperatures (ie a soldering iron) the flux prevents the oxidation. If you were to solder without flux the solder joint would be weak and possibly completely nonconductive.

The rule for voltage in a series circuit is that the signed sum of the voltage drops around the circuit add up to zero. This is Kirchoff's voltage law.

Take a simple circuit of a 1.5V battery and light bulb in series with each other. Starting at the battery negative terminal, the voltage from negative to positive is +1.5V. Starting at the top of the light bulb (the end connected to the battery positive terminal), the voltage from top to bottom is -1.5V. The two drops (rises, in this case), +1.5V and -1.5V add up to zero.

Note that the simple example above, is also a parallel circuit. The implication is that elements of a parallel circuit have the same voltage across them.

Lets add a second bulb in series with the first. The voltage going up across the battery is still +1.5V, while the voltage going down across each bulb is -0.75V. Again, the sum is zero.

You can take this to any level of complexity during circuit analysis. Find the series or parallel elements and calculate drops around the series part or find the equivalent voltages across the parallel parts, combine that with other techniques such as Kirchoff's current law, and Norton and Thevanin equivalents, and you can analyze any circuit.

ANSWER: In a series circuit since the current remains the same for every items the voltage will vary according to ohm law

The Fourier transform allows you to convert between time domain and frequency domain and back. Certain manipulations, such as filters, are easier to implement in the frequency domain, particularly when the representation is digital. You can also compress and shift the bandpass of a signal for easier transmission, and then convert it back at the receiving end.

a multimeter probably has a Ohm meter as well. If yes, use it and make sure you have the correct scale adjusted. If there is no Ohm meter you should calculate the resistance using Ohms Law. So if you use your multimeter as an Amp meter (in series with the unknown resistor) and you apply a know voltage across you should be able to calculate the resistance by dividing the voltage you applied by the current you meassured (R=v/I)

ANSWER: 1 make sure ther is no external power connected 2 short the leads together and adjust for zero reading on the meter. This step is necessary to eliminate the internal battery drifting with time.

Unlike voltage and amps reading the scaling of the meter is not important to begin with since a peg meter or a overflow will not destroy the meter immediately but do change the scale to get maximum deflection or digital display.That it

One way to increase the range of a walkie talkie is to increase the elevation of the set. Climbing a tree or a hill can increase the range significantly.

With the increase in temperature, the concentration of minority carriers starts increasing. Eventually, a temperature is reached called the critical temperature (85° C in case of germanium and 200° C in case of silicon) when the number of covalent bonds that are broken is very large and the number of holes is approximately equal to number of electrons. The extrinsic semiconductor now behaves essentially like an intrinsic semi-conductor.

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If two 1-ohm resistors are connected in parallel, their resistance is 0.5 ohms. If they are connected in series, their resistance is 2 ohms. It is not possible to connect only two resistors in series parallel.