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 : What are four types of tape errors that can degrade a magnetic recording system’s performance?
Last Answer : Signal dropout, noise, skew, and level. Dropout is the most common.
Description : What are the four basic parts of a magnetic tape recorder's tape transport system?
Last Answer : a. Tape reeling system. b. Tape speed control system. c. Electronic subsystem. d. Basic enclosure.
Description : What number harmonic is the primary harmonic distortion in magnetic tape recorders?
Last Answer : Third-order harmonic.
Description : What two types of record and reproduce electronics are used by magnetic tape recorders?
Last Answer : . a. Direct record (AM). b. Frequency modulation (FM).
Description : Magnetic tape recorders can have up to three different heads installed. What are the three functions performed by a recorder's heads?
Last Answer : Record, reproduce, and erase.
Description : What method for erasing magnetic tape is much more effective and reliable than using a recorder’s erase head?
Last Answer : Using a magnetic tape degausser
Description : What are two disadvantages of using a recorder’s erase head to erase data recorded on a magnetic tape?
Last Answer : Using an erase head is slow, and it may not completely erase the tape.
Description : After using a tape that was stored in an area where temperatures exceeded 130º F you notice pieces of oxide sticking to the recorder's tape-transport mechanism, to its magnetic heads, and onto the tape. What is the probable cause of these symptoms?
Last Answer : Oxide shedding. At temperatures above 130º F, oxide coating becomes soft and sheds.
Description : Digital magnetic tape recorders used to store and retrieve digital data fall into what three categories?
Last Answer : a. Computer-compatible digital tape recorders. b. Telemetry digital tape recorders. c. Instrumentation digital tape recorders
Description : What type of reeling system best controls a tape recorder's tape tension during starts and stops?
Last Answer : A tape buffering reeling system
Description : What causes flutter in a tape recorder’s output?
Last Answer : Non-uniform tape motion caused by variations in tape speed.
Description : Technical manuals for tape recorders can state the SNR in what three different ways?
Last Answer : a. Root-mean-square (RMS) signal-to-RMS noise. b. Peak-to-peak signal-to-RMS noise. c. Peak signal-to-RMS noise.
Description : You plan to measure your tape recorder’s SNR. What test equipment will you need?
Last Answer : A VTVM and a signal generator.
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 head driver circuit of a tape recorder’s FM record electronics (figure 5-4) performs what function?
Last Answer : It amplifies the frequency-modulated output from the record oscillator and sends it to the record head.
Description : The equalization and phase correction circuit in a tape recorder’s direct reproduce electronics (figure 5-2) performs what function?
Last Answer : It generates an equalization signal which corrects any frequency response problems in the input signal from the pre-amplifier circuit.
Description : The head driver circuit in a tape recorder’s direct record electronics component (figure 5-1) performs what function?
Last Answer : It takes the signal from the summing network, amplifies it, and sends it to the record head for recording.
Description : List four rules you should follow when storing magnetic tape to protect it from damage.
Last Answer : a. Make sure the tape is wound properly on the reel hub, b. store tapes vertically, c. keep storage area at right temperature and humidity, d. store away from equipment that generates stray magnetic fields.
Description : The frequency-response specification of your tape recorder reads within +/ - 3 dB from 150 Hz to 150 kHz at 60 ips. What does this mean?
Last Answer : The recorder can record all frequencies between 150 Hz and 150 kHz at 60 ips without varying the output amplitude more than 3 dB.
Description : How often should you demagnetize a recorder's magnetic heads?
Last Answer : Every 8 to 25 hours depending on the manufacturer's recommendations.
Description : What type of equipment should you use to demagnetize your recorder's magnetic heads?
Last Answer : A hand-held degausser like the manual degaussers used for degaussing magnetic tape.
Description : How should you clean your recorder's magnetic heads?
Last Answer : With a cotton-tipped applicator soaked in either isopropyl alcohol or a head cleaner recommended by the recorder's manufacturer.
Description : What two specifications determine the maximum frequency that a recorder's record and reproduce heads will be able to transfer?
Last Answer : a. Size of the headgap. b. Speed of the magnetic tape.
Description : Which of the two types of magnetic tape is used to record audio and instrumentation type signals in the VLF to 2.5MHz frequency range?
Last Answer : Analog magnetic tape.
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 : Which single phase ac motor will you select for record players and tape recorders? a) Hysteresis motor b) Shaded pole motor c) Reluctance motor d) Two value capacitor motor
Last Answer : Which single phase ac motor will you select for record players and tape recorders? Hysteresis motor
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 : 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 : A recorder's erase head is always placed in what sequence on the record/reproduce track?
Last Answer : . First, before the record and reproduce heads.
Description : Why are record heads always placed before reproduce heads on recorders?
Last Answer : Allow you to monitor the signals you're recording.
Description : An output device that uses words or messages recorded on a magnetic medium to produce audio response is A) Magnetic tape B) Voice response unit C) Voice recognition unit D) Voice band
Last Answer : Answer : B
Description : An output device that uses words or messages recorded on a magnetic medium to produce audio response is b. Magnetic tape c. Voice response unit d. Voice recognition unit e. Voice band
Last Answer : Voice response unit
Last Answer : d. Voice recognition unit
Last Answer : b. Magnetic tape
Description : What equipment should you use to de-magnetize a magnetic tape transport?
Last Answer : A hand-held degausser.
Description : Sometimes it's necessary, but why should you avoid using cotton swabs when cleaning a magnetic tape transport?
Last Answer : Cotton swabs are not lint free.
Description : . How do tape transports with differential velocity capstans maintain a constant tape tension in the area around the magnetic heads?
Last Answer : The supply capstan is slightly larger than the take-up capstan. This causes the take-up capstan to pull the tape slightly faster than the supply capstan feeds the tape.
Description : Why is it important to minimize TBE jitter in magnetic tape recordings where precise timing relationships exist between two or more signals?
Last Answer : The jitter could cause noise and a loss of accuracy.
Description : What two preventive maintenance actions must you do regularly to increase magnetic head life and to ensure good tape recording and playback?
Last Answer : a. Keep the heads clean. b. Keep the heads demagnetized.
Description : What is the correct way to hold a magnetic tape reel?
Last Answer : Always hold reel by the hub, never by the flanges. Never touch the working tape surface.
Description : You notice steps in the tape pack such as those in figure 2-3. What causes this and how does it damage the magnetic tape?
Last Answer : Pack slip. It's caused by loosely wound tape on a reel that is exposed to excessive vibration or heat. The vibration or heat causes the tape to shift, causing steps in the tape pack. The uneven tape will then rub against the reel's sides and the recorder's tape guides.
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 : Your activity stores its magnetic tape in an area where the temperature is 100º F. What two types of environmental damage could occur that would make these tapes unusable?
Last Answer : Head-to-tape sticking and layer-to-layer adhesion
Description : Environmental damage to magnetic tape can occur when the tape is stored in an area that exceeds what ideal temperature and humidity ranges?
Last Answer : Ideally, use and store tape at 60 to 80º F and at 40 to 60% relative humidity.
Description : If magnetic tape is stored in areas with temperature and humidity extremes, what are three types of tape damage that may occur?
Last Answer : Oxide shedding, layer-to-layer sticking, and tape deformation.
Description : What type of magnetic tape is used to record computer programs and data, and what are the additional thickness and quality standards for this type of tape?
Last Answer : digital magnetic tape is for computer programs and data. Its base material is about 50% thicker. The tape’s surface must not have blemishes or coating flaws because losing even one digital data bit could ruin the recorded computer program or data.
Description : Why is plastic magnetic tape used more than metal tape?
Last Answer : Plastic tape is used more than metal because it’s more flexible, resists mildew and fungus, and is very stable at high temperatures and humidity.
Description : Magnetic tape is made of what three basic materials?
Last Answer : a. Base material. b. Coating of magnetic oxide particles. c. Glue that bonds the particles to the base.