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. Heating of capacitor in the oscillator C. Poor soldered connections D. Faulty capacitor, resistor, tubes or resistors

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. Heating of capacitor in the oscillator
C. Poor soldered connections
D. Faulty capacitor, resistor, tubes or resistors
by

1 Answer

Answer :

B. Heating of capacitor in the oscillator
by

Related questions

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 B. Power supply voltage changes C. Loose connections in the oscillator, amplifier, or antenna circuits D. DC and RF heating of resistors, causing then to change values.

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.

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 oscillation. A. Heating and expansion of oscillator coil B. DC and RF ac heating of resistors which cause change in values C. Heating of capacitor in the oscillatorD. Loose connections in the oscillator, amplifier, or antenna circuits.

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.

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

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

How is it possible to lower the resonant frequency of Hertz dipole antenna? A. By reducing the frequency at the transmitter B. By connecting a capacitor in series with the antenna C. By the connecting a resistor in series with the antenna D. By connecting an inductor in series with the antenna

Description : How is it possible to lower the resonant frequency of Hertz dipole antenna? A. By reducing the frequency at the transmitter B. By connecting a capacitor in series with the antenna C. By the connecting a resistor in series with the antenna D. By connecting an inductor in series with the antenna

Last Answer : D. By connecting an inductor in series with the antenna

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 high power output. The purpose of which is to develop a good frequency stability. A. Goldsmith B. MOPA C. Alexanderson D. Hartley

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

When troubleshooting a console circuit card suspected of being faulty, first check operating voltages, clean the card and then _________________. A. make sure wired connections and push-on connectors are tight B. test each resistor and capacitor on the card with an ohmmeter C. check the continuity of all printed circuit traces with an ohmmeter D. measure the gain of each transistor or integrated circuit

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Last Answer : Answer: A

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

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Refer to the deviation of the operating frequency of a crystal oscillator from its nominal value due to temperature variations. A. Drift B. Flash over C. Frequency deviation D. Deviation ratio

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When troubleshooting a console circuit card which is suspected of being faulty, the first step would be to _____. A. pull the card and measure the value of all resistors B. check for the correct value and polarity of all power connections to the card C. de-energize and pull the card to visually inspect for burned components D. check for continuity of circuit board traces and then the gain of each transistor

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Last Answer : Answer: C

How can receiver desensitizing be reduced? A. Increase the receiver bandwidth B. Ensure good RF shielding between the transmitter and receiver C. Increase the transmitter audio gain D. Decrease the receiver squelch, gain.

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A solid-state circuit is inoperative; the FIRST action that should be taken is to ____________. A. wiggle all the components to check for loose connections B. check all the resistors C. change all transistors D. check the DC supply voltage

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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

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Device used to store energy in electrical circuits is A. resistor B. inductor C. capacitor D. diode

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Increasing the electrical length of an antenna means A. add an inductor in parallel B. add a capacitor in series C. add an inductor series D. add a resistor is series

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What component in the telephone set has the primary function of interfacing the handset to the local loop? A. Varistor B. Induction coil C. Resistor D. Capacitor

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In actual applications, electrical connections to 'R1-R2' of figure 'A' and to 'R1-R2- R3' of figure 'B' shown in the illustration are made by ______________. EL-0092 A. soldered contacts B. spliced and taped connections C. slip rings and brushes D. solderless crimp-on connectors

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What transmission method uses a stable cw reference oscillator, which is locked in phase with the transmitter frequency?

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In an fm transmitter, when does an oscillator generate only a steady frequency?

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In a radio transmitter, the frequency of the crystal oscillator will be stable for a long time if the quality factor

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The frequency stability of the oscillator output is maximum in _____.

Description : The frequency stability of the oscillator output is maximum in _____.   (a) Crystal oscillator (b) Phase shift oscillator (c) LC oscillator (d) Wien bridge oscillator 

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A capacitor discolored due to excessive heat should be _____________. A. calibrated B. replaced C. cooled D. soldered

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What is the local oscillator (mixer) frequency of the satellite with an uplink frequency in GHz band? A. 3500 MHz B. 4500 MHz C. 2225 MHz D. 2555 MHz

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An FM receiver whose intermediate frequency is 10.7 MHz, is experiencing image channel interference from a station transmitting on 121.1 MHz. If the local oscillator is tracking above, the receiver is tuned to A. 131.8 MHz B. 110.4 MHz C. 142.5 MHz D. 99.7 MHz

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What is the proper procedure for suppressing electrical noise in a mobile station? A. Apply shielding and filtering where necessary B. Insulate a all plain sheet metal surfaces from each other C. Apply anti-static spray liberally to all nonmetallic D. Install filter capacitors in series with all dc wiring

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What is the meaning of the term “velocity factor” of a transmission line? A. The ratio of the characteristic impedance of the line to the terminating impedance B. The index of shielding for coaxial cable. C. The velocity of the wave on the transmission line multiplied by the velocity of light in a vacuum. D. The velocity of the wave on the transmission line divided by the velocity of light in a vacuum.

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What is the meaning of the term velocity factor of a transmission line? A. The index of shielding for coaxial cable B. The velocity of the wave on the transmission line multiplied by the velocity of light in vacuum C. The ratio of the characteristic impedance of the line to the terminating impedance D. The velocity of the wave on the transmission line divided by the velocity of light in a vacuum

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An advantage of optic fiber rejecting an induced noise signals from magnetic field or solar storms flux. A. Electric hazard B. Cross talk C. Immunity to noise D. Shielding

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Which one is not the basic electrical protection measures in the Philippine Electronics Code? A. Voltage/ current limiting and interrupting B. Undergrounding C. Grounding and bonding D. Shielding

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What can cause terminated wires to loosen resulting in broken or intermittent connections?

Description : What can cause terminated wires to loosen resulting in broken or intermittent connections?

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What can cause terminated wires to loosen resulting in broken or intermittent connections?

Description : What can cause terminated wires to loosen resulting in broken or intermittent connections?

Last Answer : Heating and coolingVibration

When troubleshooting a console circuit card suspected of being faulty, the last step would be to _______________. A. check the fuses and voltage levels of all power supplies in the console B. clean dust and debris from the card and burnish the sliding connections C. make sure all connections are tight including wire wrappings and push-on types D. substitute a new or repaired spare card and check the operation of the circuit

Description : When troubleshooting a console circuit card suspected of being faulty, the last step would be to _______________. A. check the fuses and voltage levels of all power supplies in the console B. clean dust ... -on types D. substitute a new or repaired spare card and check the operation of the circuit

Last Answer : Answer: D

When soldering a printed circuit board component, you should be careful to prevent damage by _________. A. quickly heating the joints, using a high wattage iron B. using the soldering iron tip sparingly C. using only acid cord solder D. applying mechanical pressure to the joints being soldered

Description : When soldering a printed circuit board component, you should be careful to prevent damage by _________. A. quickly heating the joints, using a high wattage iron B. using the soldering iron tip sparingly C. using only acid cord solder D. applying mechanical pressure to the joints being soldered

Last Answer : Answer: B

Which of the following antennas is used for testing and adjusting a transmitter for proper modulation, amplifier operation and frequency accuracy? A. Elementary B. Real C. Isotropic D. Dummy

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Last Answer : A. 6.065 GHz

What is the path attenuation between transmitter and receiver at a frequency of 1.2 Ghz and a distance of 11,000 mi? A. 119 dB B. 115dB C. 179dB D. 174dB

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One of the following prevents a transmitter from emitting a signal that interferes with other stations on frequency during the test. A. Use of low height antenna B. Use of grounded antenna C. Use of dummy antenna D. Use of shielded antenna radiator

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Referred to as an average power from the radio transmitter supplied to the antenna transmission line taken during one radio frequency cycle under no modulation. A. Carrier power B. Rated power C. Peak envelop power D. Mean power

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