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 : 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 : 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 control electronics component of a floppy or hard disk drive performs what three main functions?
Last Answer : a. Spins the disk at the correct speed. b. Moves the heads across the recording surface. c. Tells the write/read heads when to write data and when to read it.
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 : 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 : How do FM record electronics differ from AM (direct record) electronics?
Last Answer : Instead of recording the signal just as it appears at the recorder’s input, FM record electronics records a frequency-modulated carrier signal from a record oscillator (figure 5-4) onto the magnetic tape
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 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 causes flutter in a tape recorder’s output?
Last Answer : Non-uniform tape motion caused by variations in tape speed.
Description : What number harmonic is the primary harmonic distortion in magnetic tape recorders?
Last Answer : Third-order harmonic.
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 : 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 : 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 : 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 : 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 : 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 : Why are record heads always placed before reproduce heads on recorders?
Last Answer : Allow you to monitor the signals you're recording.
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 : What is the major difference between direct reproduce electronics and FM reproduce electronics?
Last Answer : FM record electronics must use a limiter and demodulator circuit (figure 5-5) to demodulate the signal intelligence from the carrier frequency.
Description : As shown in the illustrations, most console schematic diagram sheets have letters and/or numbers placed across the top and numbers along the side boarders. The purpose of these markings is to ... small hole over a letter and number, what month and year that particular page was redrawn
Last Answer : Answer: A
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 : 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 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 : What format of digital tape recording is normally used to record instrumentation or telemetry data?
Last Answer : Serial digital magnetic tape recording.
Description : In the illustration, the component labeled 'EXC' is _______. EL-0003 A. a separate class II regulated DC generator for critical direct current loads B. a generator feeding the FLD ... to drive the governor for turbogenerator speed. D. the electronic driver for the switchboard metering circuits
Last Answer : Answer: B
Description : A tape pack has gaps in the tape winding as shown in figure 2-5. What causes this condition?
Last Answer : Tape is loosely wound on reel.
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 : 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 : A tape pack is buckled and deformed as shown in figure 2- 4. What are three possible causes for this condition?
Last Answer : a. Reel has a distorted hub, b. tape wound over small particle deposited on hub, and c. tape wound on reel with tension increasing toward end of winding.
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 : . After rewinding a tape onto its supply reel, you examine the tape pack and notice pile-ups of tape resembling the example in figure 2-2. What causes this condition?
Last Answer : The tape is stopped too quickly when winding or rewinding.
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 : 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 : How does relative humidity over 95% cause excessive tape and head wear?
Last Answer : High humidity causes increased friction as the tape passes over the heads.
Description : Which component in figure 3-7 develops the af signal at the input?
Last Answer : R1.
Description : In the subtract mode, a 1 at C0 performs what portion of the R’s complemen
Last Answer : Add 1 portion.
Description : Multimode optical fibers can have a step-index or graded index refractive index profile. Which fiber, multimode step-index or multimode graded-index fiber, usually performs better?
Last Answer : Multimode graded-index fiber
Description : What is a central set of programs called that manages the execution of other programs and performs common functions like read, write, and print?
Last Answer : Operating system.
Description : Which of the following is used to define the service component that performs the service? a) WSDL b) SCDL c) XML d) None of the mentioned
Last Answer : SCDL
Description : A component called the ____________ performs resource allocation and management on behalf of specific user applications. a) IGG manager b) GFS manager c) DVE manager d) DVA manager
Last Answer : DVE manager
Description : What component in an amplifier circuit tends to limit the low-frequency response of the amplifier?
Last Answer : The coupling capacitor (C3).
Description : The area between base 1 and base 2 in a UJT acts as what type of common circuit component?
Last Answer : Variable resistor.