Description : When the reverse bias on a varactor is increased, what happens to the effective capacitance?
Last Answer : Capacitance decreases.
Description : The varactor is a pn junction that acts as what type of electronic device?
Last Answer : Variable capacitor.
Description : What characteristic of a varactor is used in an fm modulator?
Last Answer : Capacitance.
Description : What property of liquid crystals makes them useful for displays?
Last Answer : Liquid crystals can rotate the angle of polarization of light bydifferent amounts depending on the strength of an electric fieldacross them. This allows them to be used in high speed opticalswitches controlling the amount of light visible in pixels of adisplay.
Description : What are the three fundamental quantities involved in radar displays?
Last Answer : Range, bearing, and elevation.
Description : Flat panel displays are designed to reduce what problem of a crt display?
Last Answer : Reduce the depth of the crt display caused by the length of the tube.
Description : High-resolution, bit-mapped displays are useful for displaying _____________ a) clearer characters b) graphics c) more characters d) all of the mentioned
Last Answer : c) more characters
Description : Draw the circuit diagram of varactor diode FM modulator and explain its working.
Last Answer : Varactor diode modulator is the direct method of FM generation wherein the carrier frequency is directly varied by the modulating signal. A varactor diode is a semiconductor diode whose ... the magnitude of frequency change is proportional to the amplitude of the modulating signal voltage.
Description : Draw the symbols of Schottkey-diode and Varactor diode.
Last Answer : Schottkey-diode
Description : The following is not an application of varactor diode: a) Parametric amplifier b) Frequency tuner c) Voltage controlled oscillator d) Phase shifter
Last Answer : The following is not an application of varactor diode: a) Parametric amplifier b) Frequency tuner c) Voltage controlled oscillator d) Phase shifter
Description : What electrical property does an ammeter measure?
Last Answer : Current.
Description : What electrical property is used by all the meter movements discussed so far?
Description : __________ are devices that convert electrical energy into light. A. Emissive Displays B. Non-Emissive Displays C. Both (A) and (B) D. None of the Above
Last Answer : A. Emissive Displays
Description : Ferrite devices are useful in microwave applications because they possess what properties?
Last Answer : Magnetic properties and high resistance
Description : What is the filter called in which the low frequencies do not produce a useful voltage?
Last Answer : High-pass filter, low-frequency discriminator, or low-frequency attenuator.
Description : What type of diagram would be most useful for wiring a relay into a circuit?
Last Answer : . Terminal diagram.
Description : What type of diagram is the most useful in learning the overall operation of a system?
Last Answer : A schematic diagram.
Description : Why is radiotelephone one of the most useful methods of military communications?
Last Answer : It is direct, convenient and easy to use.
Description : What type coupling would be most useful for an audio amplifier between the first and second stages?
Last Answer : RC coupling.
Description : What type of flux must be used in all electrical and electronic soldering?
Last Answer : Noncorrosive, nonconductive rosin fluxes.
Description : What is the tin-lead alloy percentage of solder used for electrical connectors, splices, and terminal lugs?
Last Answer : 60-percent tin and 40-percent lead (60/40 solder).
Description : When working on electrical equipment, why should you use only one hand?
Last Answer : . To minimize the probability of providing a path for current through your body.
Description : Before working on electrical equipment containing capacitors, what should you do to the capacitors?
Last Answer : Discharge them by shorting them to ground.
Description : Which quantity (voltage or current) determines the intensity of an electrical shock?
Description : What restrictions are placed on the use of the electrical lock method?
Last Answer : It can be used only if the leads of the synchro are accessible and the rotor is free to turn.
Description : What is the output voltage of a CT when it is set on electrical zero?
Last Answer : Zero or minimum voltage.
Description : What is the name given to the electrical output of a CT?
Last Answer : Error signal
Description : What is the amplitude and voltage induced into the rotor when the CX is turned 90º while the CT remains on electrical zero?
Last Answer : The voltage is maximum and in phase with the ac excitation voltage to the CX.
Description : When a CT is on electrical zero, what is the relationship between its rotor and the S2 winding?
Last Answer : They are perpendicular to each other.
Description : What semiconductor device produces electrical energy when exposed to light?
Last Answer : Photovoltaic cell.
Description : What type of electrical diagram is used to identify the components of a system?
Last Answer : A pictorial diagram.
Description : What is the purpose of the green conductor in a power tool or electrical appliance cable?
Last Answer : To prevent electrical shock to the operator in case there is an electrical short to the frame of the appliance or too.
Description : Which part of a fiber optic transmitter converts the processed electrical signal to an optical signal?
Last Answer : The optical source.
Description : . Which part of the receiver amplifies the electrical signal to a level suitable for further signal processing?
Last Answer : Amplifier.
Description : The domain in a gallium-arsenide semiconductor has what type of electrical field when compared to the other regions across the body of a semiconductor?
Last Answer : A field of much greater intensity.
Description : Who is responsible for meeting environmental and electrical requirements of a system?
Last Answer : Equipment designers (planners).
Description : What are some examples of electrical equipment which use magnetism?
Last Answer : Motors, generators, speakers, computers, televisions, tape recorders, and many others
Description : In swept-frequency testing the impedance of a transmission line, what electrical characteristic is actually being measured?
Last Answer : Swr on the transmission line.
Description : What are the two types of electrical communications?
Last Answer : Radio and wire.
Description : A step transmitter is a modification of what electrical device?
Last Answer : Rotary switch.
Description : The transmission of still images over an electrical communications system is known as what?
Last Answer : Facsimile.
Description : Generators convert mechanical motion to electrical energy using what principle?
Last Answer : Magnetic induction
Description : What should you do if you become aware of a possible malfunction in a piece of electrical equipment?
Last Answer : You should immediately report this condition to a qualified technician
Description : What is the term applied to the rate at which a mechanical or electrical force causes motion?
Last Answer : Power
Description : What electrical quantity is measured by a watt-hour meter?
Last Answer : Energy.
Description : What electrical quantity is measured by a wattmeter?
Description : What electrical quantity is measured by an ohmmeter?
Last Answer : Resistance.
Description : What electrical quantity is measured by a voltmeter?
Last Answer : Voltage.
Description : List seven advantages of fiber optics over electrical systems.
Last Answer : Advantages of fiber optics are improved system performance, immunity to electrical noise, signal security, electrical isolation, reduced size and w
Description : The operator of electrical motors should keep a constant check on the loads they carry because _____________. A. low loads necessitate frequent insulation cleaning B. exceeding nameplate values shortens ... wasted if full loading is not utilized D. power factor correction methods are load dependent
Last Answer : Answer: B