Description : What transmission method uses a stable cw reference oscillator, which is locked in phase with the transmitter frequency?
Last Answer : Pulse-Doppler.
Last Answer : Antenna-to-ground capacitance can cause the oscillator frequency to vary.
Description : State the method used to increase the speed of keying in a cw transmitter.
Last Answer : Machine keying.
Description : When a transmitter uses a high-power oscillator to produce the output pulse, what switches the oscillator on and off?
Last Answer : High-voltage pulse from the modulator.
Description : In an fm transmitter, when does an oscillator generate only a steady frequency?
Last Answer : When no modulation is present.
Description : How does heterodyning distinguish between cw signals?
Last Answer : By giving a different beat frequency for each signal.
Description : What principle is used to help distinguish between two cw signals that are close in frequency?
Last Answer : Heterodyning.
Description : What are the essential components of a cw receiver system?
Last Answer : An antenna, tank circuit for tuning, rectifier for detection, filter to give constant output, and an indicator device
Description : Name three advantages of cw transmission
Last Answer : A high degree of clarity even under severe noise conditions, long-range operation, and narrow bandwidth.
Description : What are the three requirements for cw transmission?
Last Answer : A method of generating oscillations, a method of turning the oscillations on and off (keying), and an antenna to radiate the energy.
Description : One of the following is a possible cause for a slow drift of frequency in a self-exited transmitter oscillator circuits resulting to a poor frequency stability. A. Loose shielding B. ... capacitor in the oscillator C. Poor soldered connections D. Faulty capacitor, resistor, tubes or resistors
Last Answer : B. Heating of capacitor in the oscillator
Description : How do you eliminate radio frequency variation of an oscillator transmitter caused by its supply voltage? A. Use new power supply B. Lossen power supply shielding C. Use of regulated power supply D. Use of high capacitor in the supply circuit
Last Answer : C. Use of regulated power supply
Description : One of the following is a high powered RF ac basic transmitter that has two or more stages, the oscillator stage which determines the frequency opereation and RF amplifier stage orstages that develop the ... to develop a good frequency stability. A. Goldsmith B. MOPA C. Alexanderson D. Hartley
Last Answer : B. MOPA
Description : Type of emission produced by one of the early radio transmitter in trains of damped RF ac waves where its oscillator is coupled to a long wire antenna, normally used in radio telegraph and having sidebands on its carrier. A. Digital emission B. Key emission C. Cycle emission D. Spark emission
Last Answer : D. Spark emission
Description : The stability of transmitted signal from a simple Hartley oscillator single transmitter which is coupled to and antenna wire affected by ______. A. Chirping of oscillator B. Closer coupling between the oscillator and the antenna. C. Location of antenna D. Material of antenna
Last Answer : B. Closer coupling between the oscillator and the antenna.
Description : One of the following is a possible cause of an abrupt frequency variation in a self exited transmitter oscillator circuits resulting to a poor frequency stability to hold a constant frequency ... capacitor in the oscillator D. Loose connections in the oscillator, amplifier, or antenna circuits.
Last Answer : D. Loose connections in the oscillator, amplifier, or antenna circuits.
Description : Which of the following is one of the possible causes for a slow drift of frequency in a self exited transmitter oscillator circuits resulting to a poor frequency stability? A. Poor soldered connections ... , or antenna circuits D. DC and RF heating of resistors, causing then to change values.
Last Answer : D. DC and RF heating of resistors, causing then to change values.
Description : In a radio transmitter, the frequency of the crystal oscillator will be stable for a long time if the quality factor of the crystal resonator is (a) > 100 (b) > 500 (c) > 1000 (d) > 20000
Last Answer : In a radio transmitter, the frequency of the crystal oscillator will be stable for a long time if the quality factor of the crystal resonator is > 1000
Description : What component in a blocking oscillator controls pulse width?
Last Answer : Transformer.
Description : What signal is used to synchronize the coherent oscillator to a fixed phase relationship with the transmitted pulse?
Last Answer : Coho lock pulse.
Description : What is the primary advantage of power-amplifier transmitters over keyed-oscillator transmitters?
Last Answer : Frequency stability.
Description : Name a disadvantage of sine-wave oscillator synchronizers.
Last Answer : It requires additional shaping circuits.
Description : What basic circuits meet the requirements of an externally synchronized master oscillator?
Last Answer : Sine-wave oscillator, single-swing blocking oscillator, and master trigger (astable) multivibrator.
Last Answer : . It requires additional shaping circuits.
Description : What type of multivibrator can be used as a radar master oscillator?
Last Answer : Free-running.
Description : What is the polarity of the first alternation of the tank circuit in an emitter-loaded npn pulsed oscillator?
Last Answer : Negative
Description : Why is a high-gain transistor used in the phase-shift oscillator?
Last Answer : Because of the losses encountered in the RC networks.
Description : Which components provide the regenerative feedback signal in the phase-shift oscillator?
Last Answer : Resistor-capacitor networks.
Description : What is the identifying feature of a Colpitts oscillator?
Last Answer : Split capacitors.
Description : What is the difference between the series-fed and the shunt-fed Hartley oscillator?
Last Answer : In the series-fed Hartley oscillator, dc flows through the tank circuit.
Description : What is the main difference between the Armstrong oscillator and the Hartley oscillator?
Last Answer : Feedback coil. Armstrong uses a separate coil. Hartley uses a tapped coil.
Description : Which oscillator uses tapped capacitors for feedback?
Last Answer : Colpitts.
Description : Which oscillator uses a tapped inductor for feedback?
Last Answer : Hartley.
Description : Which oscillator uses a tickler coil for feedback?
Last Answer : Armstrong.
Description : In a heterodyne-type frequency meter, what is the difference between the oscillator frequency and the unknown frequency?
Last Answer : Beat frequency.
Description : What characteristic of a gunn oscillator is inversely proportional to the transit time of the domain across the semiconductor?
Last Answer : The frequency.
Description : Why is the tunnel diode loosely coupled to the cavity in a tunnel-diode oscillator?
Last Answer : To increase the stability.
Description : What determines the frequency of a tunnel-diode oscillator?
Last Answer : The tuned circuit or cavity frequency.
Description : Name two methods of oscillator keying.
Last Answer : Plate keying and cathode keying.
Description : What precaution should you take when substituting a synchro tester in a circuit for a transmitter?
Last Answer : Use only one receiver so as not to overload the tester.
Description : What is the most likely problem if the transmitter shaft reads 0º when the receiver shaft indicates 180º?
Last Answer : The rotor leads on either the transmitter or the receiver are reversed.
Description : What is the relationship between the transmitter and receiver stator voltages when their rotors are in correspondence?
Last Answer : The voltages are equal and oppose each other.
Description : What is the physical difference between a synchro transmitter and a synchro receiver?
Last Answer : A synchro receiver uses some form of damping to retard excessive oscillations or spinning.
Description : Describe the zero-position of a synchro transmitter.
Last Answer : The transmitter is in its zero-position when the rotor is aligned with the S2 stator winding.
Description : What unit of measurement refers to the torque of a synchro transmitter
Last Answer : Ounce-inches.
Description : What are some disadvantages of operating a transmitter at or near the muf?
Last Answer : Frequent signal fading and dropouts.
Description : What are three ways of controlling the amount of transmitter-generated emi?
Last Answer : (a) filtering and shielding of the transmitter (b) limiting bandwidth (c) cutting the antenna to the
Description : Transmitter power readings are most often referenced to what power level?
Last Answer : 1 milliwatt.