Description : The skew specification of your multi-tracked tape recorder reads " +/ - 0.20 microseconds between adjacent tracks on the same head stack at 120 ips." What does this mean?
Last Answer : One of the tracks on a magnetic head could lead or lag the track next to it by as much as 0.20 microseconds at 120 ips.
Description : A recorder’s harmonic-distortion specification reads 2% third harmonic of a 100-kHz signal at 60 ips. What does this mean?
Last Answer : The recorder has 2% third-harmonic distortion of a 100-kHz signal at 60 ips.
Description : While measuring frequency response, as the signal generator approaches the lowest and highest frequency the recorder can effectively record, the VTVM reading drops to less than - 3 dB. What does this indicate?
Last Answer : The upper and lower limits of the frequency response specification for that tape recorder.
Description : What category of digital tape recorder is used to record special signals with a bandwidth of less than 500 kHz?
Last Answer : Instrumentation digital tape recorders.
Description : How could you check the phase response of a tape recorder?
Last Answer : Record and reproduce a square wave and see if the output on an oscilloscope is symmetrical.
Description : How should a tape recorder with good phase response reproduce a complex waveform, such as a square wave?
Last Answer : With no distortion
Description : In acoustics, if the volume of the room is 200 m3 then at what frequency the coefficient of absorption is measured? A. 120 kHz B. 120 Hz C. 100 Hz D. 150 Hz
Last Answer : B. 120 Hz
Description : At what loudness level do pitch (in mels) and frequency (in Hz) are numerically equal? A. 0 dB B. 20 dB C. 60 dB D. 40 dB
Last Answer : D. 40 dB
Description : The noise output of a resistor is amplified by a noiseless amplifier having a gain of 60 and a bandwidth of 20 kHz. A meter connected at the output of the amplifier reads 1mV RMS. If the bandwidth of the amplifier is reduced to ... does the meter read now? A. 0.5 mV B. 0.5 µV C. 5.0 mV D. 5.0 µV
Last Answer : A. 0.5 mV
Description : The multi-track tape recorder in your computer system has a fixed skew error. What does this mean and what is the probable cause?
Last Answer : Skew means there are time differences between the individual tracks of a multi-track recorder’s magnetic head. It happens when the tape isn’t properly aligned with the head. Fixed skew happens when the tape passes over an improperly aligned magnetic head.
Description : List four factors that can degrade the frequency response of magnetic tape recorders.
Last Answer : a. A too-high or too-low bias signal level setting for the record head. b. An improper reproduce head gap. c. An improper tape transport speed. d. Poor tape-to-head contact.
Description : Which digital data encoding method helps overcome a tape recorder’s low-frequency response problems by recording two logic levels for each incoming data bit?
Last Answer : Bi-phase level encoding.
Description : How do worn or sticking tape transport guides cause dynamic skew on a multi-track recorder?
Last Answer : The tape drifts past the multi-track head at an angle.
Description : When the relative humidity is below 10%, what happens to magnetic tape and parts of a tape recorder that could cause environmental damage?
Last Answer : Dirt build-up caused by static electricity.
Description : You see a build-up of dust and lint on the take-up reel of a tape recorder. This can cause which of the four types of tape errors?
Last Answer : Signal dropout errors and level errors. The dust and lint on the reel will eventually get onto the tape where it can get between the tape and the recorder’s heads.
Description : What is the ripple frequency of a full-wave rectifier with an input frequency of 60 Hz?
Last Answer : 120 hertz.
Description : What is the Ripple frequency of a half-wave rectifier if the input frequency is 60 Hz?
Last Answer : 60 hertz.
Description : If the clock frequency to the circuit shown in the illustration were 2 kHz, what would be indicated at the output of 'FF-C'? EL-0087 A. 250 Hz B. 666 Hz C. 6 kHz D. 16 kHz
Last Answer : Answer: A
Description : What is the typical frequency used for communicating to submerged submarines? A. 100 Hz B. 500 Hz C. 4 kHz D. 200 Hz
Last Answer : A. 100 Hz
Description : What frequency is 10 octaves above 30 Hz? A. 30.72 kHz B. 30 kHz C. 300 Hz D. 307.2 kHz
Last Answer : A. 30.72 kHz
Description : What is the frequency of a 2-cm sound wave in sea water at 25˚C? A. 76 kHz B. 76 Hz C. 76 MHz D. 76 mHz
Last Answer : A. 76 kHz
Description : Human ear is most sensitive to noise in the following frequency ranges: (A) 1-2 KHz (B) 100-500 Hz (C) 10-12 KHz (D) 13-16 KHz
Last Answer : (A) 1-2 KHz
Description : Two tape recorders have signal-to-noise ratios (SNRs) of 25-dB RMS and 35-dB RMS respectively. Which of the SNRs can record and reproduce the widest range of input signals and why?
Last Answer : 35-dB RMS because the highest SNR can always record and reproduce the widest range of input signals.
Description : The carrier swing necessary to provide 80% modulation in the FM broadcasting band is __________. A. 150 kHz B. 120 kHz C. 60 kHz D. 75 kHz
Last Answer : B. 120 kHz
Description : What is the required quality factor for an SSB filter with the following data: center frequency= 1 MHz, the desired attenuation level of the unwanted sideband= 80 dB and the separation between sidebands= 200 Hz? A. 1,250 B. 12,500 C. 125,000 D. 25,000
Last Answer : C. 125,000
Description : Unit of frequency is ________________. A. Hz B. Horton C. dB D. Coulomb
Last Answer : Unit of frequency is Hz.
Description : The carrier waves used for the radio transmission have frequency upto A. 15 KHz B. 30 KHz C. 90 KHz D. 150 KHz
Last Answer : ANSWER: B
Description : What is the approximate bandwidth of an FM system with 10 kHz of modulating frequency and a 150 kHz of frequency deviation? A. 300 kHz B. 320 kHz C. 150 kHz D. 200 kHz
Last Answer : B. 320 kHz
Description : What is the most important specification of loudspeakers and microphones? A. Frequency response B. Power density C. Field Strength D. Gain
Last Answer : A. Frequency response
Description : What is the intensity of sound in normal conversation? (a) 10-20 dB (b) 30-60 dB (c) 70-90 dB (d) 120-150 dB
Last Answer : b) 30-60 dB
Description : When measuring harmonic distortion, you set the signal generator to input a 15-kHz test signal. To what frequency should you set the wave analyzer?
Last Answer : 45 kHz.
Description : A handheld digital tachometer could give a bad reading if ___________________. A. aimed directly at the shaft B. partially aimed at a 60 Hz. fluorescent light C. positioned 5-10 inches from the shaft D. the tape is too shiny
Last Answer : Answer: B
Description : When the elevation angle of a geostationary satellite is 23˚ and the transmitting frequency is 3840 MHz, what is the free space loss in dB? A. 196 dB B. 200 dB C. 150 dB D. 100 dB
Last Answer : A. 196 dB
Description : You are measuring noise in a voice channel at 7 dB test point level. The meter reads -56 dBm (FIA weighted). What is the reading in dBrnc? A. 20 B. 32 C. 35 D. 25
Last Answer : C. 35
Description : You are measuring a voice channel at a -4 dB test point level, the meter reads -73 dBm (pure test tone) convert the reading in dBmCO. A. 16 B. 18 C. 22 D. 12
Last Answer : C. 22
Description : 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
Last Answer : B. 2.656 watts
Last Answer : A. PAM
Description : In measuring noise in a voice channel at a 4 dB test point level, the meter reads -70 dBm (F1A weighted), convert the reading to pWp. A. 53 B. 93 C. 63 D. 83
Last Answer : B. 93
Description : At what power level does a 1 KHz tone cause zero interference (144 weighted)? A. 90 dB B. 90 dBm C. -90 dBm D. -90 dBm
Last Answer : D. -90 dBm
Description : ECE Board Exam March 1996 At what power level does a 1 kHz tone cause zero interference (144 weighted) ? A. -90 dB B. -90 dBm C. 90 dBm D. 90 dB
Last Answer : B. -90 dBm
Description : The capacity of a standard 4 KHz telephone channel with a 32 dB SNR is
Last Answer : The capacity of a standard 4 KHz telephone channel with a 32 dB SNR is 32953 bits/second
Description : Describe the -3 decibel (dB) optical power frequency (f3dB).
Last Answer : The -3 decibel (dB) is the lowest frequency at which the magnitude of the fiber frequency response has decreased to one half its zero-frequency value.
Description : The external exciting frequency of the system having natural frequency 15 Hz is 10 Hz. The frequency ratio will be A. 1.500 B. 0.667 C. 0.150 D. None
Last Answer : B. 0.667
Description : What is the deviation ratio for an FM-phone signal having a maximum frequency swing of plus or minus 5 kHz and accepting a maximum modulation rate of 3kHz? A. 60 B. 0.16 C. 0.6 D. 1.66
Last Answer : D. 1.66
Description : What is the baseband frequency of standard FDM basic supergroup? A. 312 to 552 kHz B. 300 to 600 kHz C. 60 to 2540 kHz D. 60 to 108 kHz
Last Answer : A. 312 to 552 kHz
Description : What is the channel spacing for SITOR frequencies? A. 500 Hz B. 170 Hz C. 300 Hz D. 3 kHz
Last Answer : A. 500 Hz
Description : What is the channel spacing for MF-HF voice frequencies? A. 2.8 kHz B. 500 Hz C. 3.5 kHz D. 3 kHz
Last Answer : D. 3 kHz
Description : A 1 Mhz carrier is amplitude modulated by a pure 200-Hz audio test tone. Which of the following combinations of frequencies represent the total content of the AM signal? A. 1 MHz and 200 Hz B. 1 MHz and 1000.2 kHz C. 999.8 kHz, 1000 kHz, and 1000.2 kHz D. 999.8 kHz and 1000.2 kHz
Last Answer : C. 999.8 kHz, 1000 kHz, and 1000.2 kHz
Description : What is the channel bandwidth of a standard analogue telephone system? A. 300-500 Hz B. 1200 kHz C. 100-300 Hz D. 300-3400 Hz
Last Answer : D. 300-3400 Hz