Description : What circuit functions does the tube in a gated-beam detector serve?
Last Answer : Limits, detects, and amplifies.
Description : Which junction of the transistor in the common-emitter detector detects the modulation envelope?
Last Answer : Emitter-base junction
Description : What simple, one-transistor detector circuit uses the heterodyne principle?
Last Answer : Regenerative detector.
Description : In its simplest form, what functions must a radar detector be capable of performing?
Last Answer : Detecting the presence of rf energy.
Description : Which components provide the regenerative feedback signal in the phase-shift oscillator?
Last Answer : Resistor-capacitor networks.
Description : List three items of information normally included in the general description section of a specification sheet for a transistor.
Last Answer : The kind of transistor, the transistor's common applications, and mechanical data
Description : What are the three transistor configurations?
Last Answer : Common emitter (CE), common base (CB), and common collector (CC)
Description : What are the three basic configurations of transistor oscillators?
Last Answer : Common collector (CC), common emitter (CE), and common base (CB).
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 : What are the four most common materials used in semiconductor detector fabrication?
Last Answer : Silicon, gallium arsenide, germanium, and indium phosphide.
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 : 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 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 : To what circuit arrangement is a common-base detector equivalent?
Last Answer : A diode detector followed by a stage of audio amplification.
Description : Which junction acts as the detector in a common-base detector?
Last Answer : Emitter-base junction.
Description : How is the output signal developed in the common-emitter detector?
Last Answer : By the collector current flow through R4.
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 : 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 : In a sawtooth generator, why is the transistor turned on for a longer time than the discharge time of the RC network?
Last Answer : To allow the capacitor time to discharge.
Description : What are the factors that limit the frequency response of a transistor amplifier?
Last Answer : The capacitance and inductance of the circuit and the interelectrode capacitance of the transistor.
Description : When you are using an ohmmeter to test a transistor for leakage, what is indicated by a low, but not shorted, reverse resistance reading?
Last Answer : A leaking transistor
Description : When you are testing the gain of an audio-frequency transistor with an ohmmeter, what is indicated by a 10-to-1 resistance ratio?
Last Answer : Normal gain.
Description : What are two transistor tests that can be done with an ohmmeter?
Last Answer : Gain and junction resistance.
Description : How is the collector lead identified on an oval-shaped transistor?
Last Answer : By the wide space between the collector lead and the other two leads (emitter and base)
Description : What safety precaution must be taken before replacing a transistor?
Last Answer : The power must be removed from the circuit.
Description : Which transistor configuration has the highest input resistance?
Last Answer : Common collector.
Description : Which transistor configuration has a current gain of less than 1?
Last Answer : Common base.
Description : What method for checking transistors is cumbersome when more than one transistor is bad in a circuit?
Last Answer : The substitution method.
Description : What is the greatest danger to a transistor?
Last Answer : Heat.
Description : In the basic transistor amplifier discussed earlier, what is the relationship between the polarity of the input and output signals?
Last Answer : The signals are opposite in polarity or 180 degrees out of phase with each other.
Description : Name the two current loops in a transistor.
Last Answer : The base current loop and the collector current loop
Description : What is the relationship between the polarity of the voltage applied to the PNP transistor and that applied to the NPN transistor?
Last Answer : The polarity of voltage applied to the PNP transistor is opposite of that applied to the NPN
Description : What are the majority current carriers in a PNP transistor?
Last Answer : Holes.
Description : What percentage of current in an NPN transistor reaches the collector?
Last Answer : 98 percent.