Description : Which junction of the transistor in the common-emitter detector detects the modulation envelope?
Last Answer : Emitter-base junction
Description : To what circuit arrangement is a common-base detector equivalent?
Last Answer : A diode detector followed by a stage of audio amplification.
Description : The varactor is a pn junction that acts as what type of electronic device?
Last Answer : Variable capacitor.
Description : The area between base 1 and base 2 in a UJT acts as what type of common circuit component?
Last Answer : Variable resistor.
Description : What are the four most common materials used in semiconductor detector fabrication?
Last Answer : Silicon, gallium arsenide, germanium, and indium phosphide.
Description : How is the output signal developed in the common-emitter detector?
Last Answer : By the collector current flow through R4.
Description : When two semiconductors of p-and ntype are brought in contact, they form p-n junction which acts like a/an – (1) Conductor (2) Oscillator (3) Rectifier (4) Amplifier
Last Answer : (3) Rectifier Explanation: P-n junction is a device which flows current in one direction when it is forward biased and when it is reverse biased it doesn't flow any current through it. So it ... (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.
Description : What disease is described by: "the toxin acts at the neuromuscular junction, preventing the release of neurotransmitters needed to inhibit muscle contraction." a. Botulism b. Tetanus c. The Plague d. A-C Are Correct
Last Answer : b. Tetanus
Description : P-n junction when reversed biased acts as a (a) Capacitor (b) inductor (c) on switch (d) off switch
Last Answer : d) off switch
Description : When two semiconductors of pand n-type are brought in contact, they form p-n junction which acts like a/an (1) Conductor (2) Oscillator (3) Rectifier (4) Amplifier
Last Answer : Rectifier
Last Answer : A pn junction acts as a Unidirectional switch.
Description : Sound waves transmitted from a source are sometimes weak when they reach the detector. What instrument is needed to boost the weak signal?
Last Answer : An amplifier.
Description : In the output of an ac error detector, what indicates the (a) direction and (b) amount of control necessary for correspondence?
Last Answer : (a) Phase. (b) Amplitude.
Description : An error signal is the difference between what two quantities fed to the CT (error detector)?
Last Answer : Input signal and feedback.
Description : Why is detector saturation not generally a problem in fiber optic communications systems?
Last Answer : Because fiber optic communications systems operate at low optical power levels.
Description : For efficient operation, should a detector have a high or low responsivity at the operating wavelength?
Last Answer : High.
Description : Describe the operation of an optical detector
Last Answer : It is a transducer that converts an optical signal into an electrical signal. It does this by generating an electrical current proportional to the intensity of incident optical radiation.
Description : What is the function of the detector?
Last Answer : To extract the modulating audio signal.
Description : How can a peak detector for pam be modified to detect pdm?
Last Answer : By making the time constant for charging the capacitor at least 10 times the maximum received pulse width.
Description : What is the time constant of the resistor and capacitor in a peak detector for pam?
Last Answer : At least 10 times the interpulse period.
Description : What characteristic of a pulse does a peak detector sample?
Last Answer : Pulse amplitude or pulse duration
Description : In its simplest form, what functions must a radar detector be capable of performing?
Last Answer : Detecting the presence of rf energy.
Description : How is a quadrature detector changed when used for phase demodulation?
Last Answer : The quadrature grid signal is excited by a reference from the transmitter.
Description : Name two advantages of the gated-beam detector.
Last Answer : Extreme simplicity, few components, and ease of adjustment.
Description : What condition must exist on both the limiter and quadrature grids for current to flow in a gated-beam detector?
Last Answer : Both grids must be positively biased
Description : What circuit functions does the tube in a gated-beam detector serve?
Last Answer : Limits, detects, and amplifies.
Description : What is the primary advantage of a ratio detector?
Last Answer : Suppresses amplitude noise without limiter stages.
Description : What is the function of an fm detector?
Last Answer : Converting frequency variations of received fm signals to amplitude variations
Description : What is the simplest form of fm detector?
Last Answer : Slope detector.
Description : which components act as the filter network in the diode detector?
Last Answer : C1 and R1.
Description : Under what circuit conditions would the shunt detector be used?
Last Answer : When the input voltage variations are too small to give a usable output from a series detector.
Description : How does the current-diode detector differ from the voltage-diode detector?
Last Answer : The current-diode detector is in parallel with the input and load.
Description : What is the function of the diode in a series-diode detector?
Last Answer : Rectifies the rf pulses in the received signal.
Description : What does the simplest diode detector use to reproduce the modulating frequency?
Last Answer : The modulation envelope.
Description : What three functions does the transistor in a regenerative detector serve?
Last Answer : Oscillator, mixer, and detector.
Description : What simple, one-transistor detector circuit uses the heterodyne principle?
Last Answer : Regenerative detector.
Description : To measure incident power, you must rotate the coupler detector of the wattmeter so that the arrow indicating power flow points toward which end of the transmission line?
Last Answer : Load.
Description : Why is the H-type T junction so named?
Last Answer : The junction arm extends in a direction parallel to the H lines in the main waveguide.
Description : When a PN junction is forward biased, what happens to the depletion region?
Last Answer : The depletion region decreases.
Description : What is the main difference in construction between normal PN junction diodes and tunnel diodes?
Last Answer : The amount of doping.
Description : Which breakdown theory explains the action that takes place in a heavily doped PN-junction with a reverse bias of less than 5 volts?
Last Answer : Zener effect.
Description : The action of a PN-junction during breakdown can be explained by what two theories?
Last Answer : Zener effect and avalanche effect.
Description : In a reverse biased PN-junction, which current carriers cause leakage current?
Last Answer : The minority carriers
Description : What type of bias opposes the PN junction barrier?
Last Answer : Forward.
Description : In order to reverse bias in a PN junction, what terminal of a battery is connected to the P material?
Last Answer : Negative.
Description : What is the name of the area in a PN junction that has a shortage of electrons and holes?
Last Answer : Depletion region
Description : What is the purpose of a PN junction diode?
Last Answer : To convert alternating current into direct current
Description : To propagate energy down an arm of a hybrid ring duplexer, the two fields at the junction of the arm and the ring must have what phase relationship?
Last Answer : 180 degrees out of phase
Description : What is the capacitive reactance across a point-contact diode as compared to a normal junction diode?
Last Answer : Lower.
Description : What is the junction arrangement of the original avalanche transit-time diode?
Last Answer : Pnin.