What is the atomic number of Rf ?

What is the atomic number of Rf ?
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1 Answer

Answer :

The atomic number of Rf is 104
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ECE Board Exam November 1996 What is the applied power if a thermal RF wattmeter is connected to a transmitter through a variable attenuator? The wattmeter reads 84 mW when 15 dB of attenuation is used. A. 4.656 watts B. 2.656 watts C. 3.656 watts D. 2.856 watts

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After the IF stages have been aligned, the next stage to align in FM receiver is. A. local oscillator B. limiter stage C. RF amplifier D. mixer stage

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Cross modulation on a receiver is eliminated at the A. RF stage B. mixer stage C. IF stage D. detector stage

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ECE Board Exam March 1996 What is the purpose of the receiver’s squelch circuit? A. To overcome fluctuations in the level the RF signal arriving at the receiver antenna B. To prevent fluctuations in the AGC bias level C. To reduce the receiver’s sensitivity to all incoming signals D. To prevent amplified noise from reaching the loudspeaker during the absence of an incoming signal

Description : ECE Board Exam March 1996 What is the purpose of the receiver's squelch circuit? A. To overcome fluctuations in the level the RF signal arriving at the receiver antenna B. To prevent ... signals D. To prevent amplified noise from reaching the loudspeaker during the absence of an incoming signal

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What is Rf value?

Description : What is Rf value?

Last Answer : It is the ratio of the distance travelled by the substance (solute) to the distance travelled by the solvent. The Rf value is a constant for a particular solvent system at a given temperature.

Which of the following methods cannot be used to increase the bandwidth for cascaded RF amplifier stages? A) Wave traps in each stage B) Stagger tuning C) A shunt damping resistor across each tuned circuit D) Doubled tuned transformers with tighter coupling

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Last Answer : A) Wave traps in each stage

What two methods are used to compensate for the problems that cause low gain in an rf amplifier?

Description : What two methods are used to compensate for the problems that cause low gain in an rf amplifier?

Last Answer : . RF transformers are used and the transistor is neutralized.

What problem is caused in an rf amplifier by a loosely coupled transformer?

Description : What problem is caused in an rf amplifier by a loosely coupled transformer?

Last Answer : A too-narrow bandpass.

What is the most common form of coupling for an rf amplifier?

Description : What is the most common form of coupling for an rf amplifier?

Last Answer : Transformer coupling.

Can a parallel LC circuit be used as the frequency determining network for an rf amplifier?

Description : Can a parallel LC circuit be used as the frequency determining network for an rf amplifier?

Last Answer : Yes.

What is the purpose of a frequency-determining network in an rf amplifier?

Description : What is the purpose of a frequency-determining network in an rf amplifier?

Last Answer : To provide maximum impedance at the desired frequency.

If current gain is required from an rf amplifier, what type of component should be used as an output coupling element?

Description : If current gain is required from an rf amplifier, what type of component should be used as an output coupling element?

Last Answer : A step-down transformer.

What is the result of pulsing a pulsed rf amplifier when no rf is present?

Description : What is the result of pulsing a pulsed rf amplifier when no rf is present?

Last Answer : Oscillations at an undesired frequency.

The Doppler effect causes a change in what aspect of rf energy that strikes a moving object?

Description : The Doppler effect causes a change in what aspect of rf energy that strikes a moving object?

Last Answer : Frequency.

Rotation of an rf-feed source to produce a conical scan pattern is identified by what term?

Description : Rotation of an rf-feed source to produce a conical scan pattern is identified by what term?

Last Answer : Nutation.

Atmospheric interference with the travel of electromagnetic energy increases with what rf energy characteristic?

Description : Atmospheric interference with the travel of electromagnetic energy increases with what rf energy characteristic?

Last Answer : Frequency.

At what point on an open-circuited rf line do voltage peaks occur?

Description : At what point on an open-circuited rf line do voltage peaks occur?

Last Answer : At 1/2 wavelength from the end and at every 1/2 wavelength along the line

If the rf amplifier discussed has an 80 milliwatt input, what would be the maximum output?

Description : If the rf amplifier discussed has an 80 milliwatt input, what would be the maximum output?

Last Answer : 800 watts.

What is the most common method of testing a fixed rf attenuator?

Description : What is the most common method of testing a fixed rf attenuator?

Last Answer : Rf substitution method.

Normally, how are high-power rf tubes tested?

Description : Normally, how are high-power rf tubes tested?

Last Answer : In their circuit.