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A track on a computer removable disk is:
1. one record.
2. divided into sectors.
3. created as data is written.
4. one continuous path.
In PC type computers, extended memory is:
1. memory above the basic 640 K.
2. memory above the basic 1 Megabyte.
3. added to basic RAM in 1mb blocks.
4. adjusted by the start up files.
Which video system has the highest resolution:
1. EGA
2. VGA
3. SVGA
4. XVGA
You would want to use a dual trace oscilloscope to measure:
1. signal differences between two points.
2. suspected resistance problems in one circuit.
3. one faulty circuit in voltage level while another is faulty in a current level.
4. one fault is video and the other is audio.
Common Intermediate Frequencies (IF’s) for AM and FM commercial broadcast receivers are:
1. 455 kHz and 1.2 GHz
2. 288 kHz and 455 kHz
3. 455 kHz and 10.7 MHz
4. 288 kHz and 10.7 MHz
Analog signal compression:
1. uses D/A converters.
2. reduces the high frequency received signal amplitude.
3. changes AM to FM.
4. primarily reduces background noise levels
Coaxial cable line losses at RF frequencies are due to:
1. wire resistance, capacitive and inductive reactance.
2. wire resistance, dielectric fading and transconductance.
3. capacitive and inductive reactance and braid leakage.
4. magnetic effects of near by materials
Standard line-level audio signals, such as the output from VCRs, DVD players, satellite receivers and set top boxes, for input to a TV, modulator or other equipment is of what amplitude?
1. 100 microvolts peak-to-peak
2. 1000 microvolts peak-to-peak
3. 1 millivolt peak-to-peak
4. 1 volt peak-to-peak
The noise level in a radio receiver is generated mostly in the:
1. IF stages.
2. Local Oscillator.
3. Audio section.
4. RF section.
The charging rate for a NiCad or Ni-MH battery should not exceed___% of its AHr, or ampere-hour rating.
1. 5
2. 100
3. 25
4. 10
Which of these in a PC would be part of disk operations?
1. Serial port board
2. DMA ports
3. CGA controller
4. SATA or IDE controller
An LED:
1. only emits visible light when forward biased.
2. can be used as a fiber optic signal source.
3. does not need high current flow protection.
4. may send or receive light signals.
A dual-trace oscilloscope may have ...
1. two electron guns.
2. one frequency control.
3. one set of position controls.
4. a Z input for intensity modulation.
The gain of an op-amp is determined by the external __ .
1. supply voltage
2. + input DC voltage
3. series input resistor
4. feedback resistor
Diodes are made from one type of material.
1. True
2. False
Which propagation condition would be significant for a UHF signal to be received at a distance of 500 miles
1. line-of-sight
2. Faraday rotation
3. groundwave
4. tropospheric ducting
A three input NAND has two low inputs and one high input. The output is:
1. low.
2. high.
3. either high or low.
4. neither high nor low.
Which of these would be considered a component of a “basic” power supply?
1. feedback circuit
2. IC regulator with short circuit protection
3. diode rectifier
4. circuit breaker box
A “Video signal” is defined as:
1. modulated RF
2. baseband including sound information
3. baseband including visual information
4. broadband RF
You are servicing a power supply and have disconnected power. It has several 250 uF capacitors connected in parallel. To avoid shock, these capacitors:
1. should be disconnected.
2. may be ignored.
3. should be discharged to chassis ground, using a suitable resistor.
4. should be isolated with a non-conductive cover and avoided.
A schematic used in electronic servicing:
1. shows the size and shape of all the components in the unit.
2. is sometimes called a block diagram.
3. shows the location and arrangement
  of components in the unit.
4. is much like a road map for following signals.
High voltage should be discharged before servicing a product. After disabling AC input
power, discharge a HV PS by:
1. shorting output to the plastic cabinet
2. disconnecting the HV lead with rubber gloves
3. draining thru a large value resistor to chassis gnd
4. shorting output of the collector heat sinks
Which of these would be an important electrical consideration in the use of a transformer?
1. the operating frequency
2. space requirements
3. environmental temperatures
4. number of laminations
If a 12v product is dissipating 50w, how much load resistance does the device represent?
1. .24 ohms
2. 24 ohms
3. 4.16 ohms
4. 2.9 ohms
An “Audio signal” is defined as
1. frequencies in the 20 Hz to 15,000 Hz range
2. baseband including visual information
3. frequencies above ultrasonic
4. broadband RF
___ will cause a generator to produce DC voltage rather than AC.
1. Slip rings
2. Load
3. Armature loops
4. The commutator
You suspect the unit has an internal short. To prevent further damage when you apply power, you should:
1. short around the main fuse or breaker and proceed, watching for heat or arcing
2. replace the unit without attempting repairs, as it probably can't be repaired safely or within reasonable time or cost limits.
3. measure the resistance at the dc connectors and compare to factory specifications.
4. insert a low resistance high wattage (100 ohm, 10 w) resistor in series with the power input.
A ripple counter:
1. is a meter that indicates the power supply ripple frequency.
2. is a network of several XNAND gates that regulates the computer oscillator.
3. is a synchronous counter that stores the counts of other counters in a computer.
4. is two or more logical flip-flops connected sequentially with the input pulses toggling the first one.
When a voltage is applied to a capacitor:
1. current is maximum at first, then reduces as the capacitor becomes charged.
2. current is constant until full charge is reached.
3. the voltage difference between the plates reduces as full charge is reached.
4. there is no difference between the plates after charging begins.
An electrolytic capacitor between the power transformer and the rectifiers in a power supply:
1. protects the diodes from power surges
2. eliminates the need for filter capacitors
3. is part of a voltage doubler circuit
4. provides that earth ground be isolated from DC ground
Information travels through optic fiber via the flow of:
1. protons
2. lumens
3. photons
4. electrons
You would most likely prefer an analog VOM over a DMM for:
1. intermittent fluctuations.
2. accuracy.
3. convenience.
4. safety.
Which of these circuits would most likely use a Zener diode?
1. a receiver I F section
2. a television tuner
3. a power regulator
4. a bridge rectifier
A block in a digital diagram is called a NOR. Which is true?
1. It may also be called a NAND.
2. It is a NOT OR or Inverted OR.
3. It will pass any single negative signal, but not more than one.
4. It must be reset after any positive signals are applied.
Which of these statements is most true relating to schematic diagrams of electronic devices?
1. They provide pictorial representations of components.
2. They supply manufacturing specifications of components.
3. They represent signal paths.
4. They provide user operational procedures.
In Personal Computer technology, ROM indicates:
1. memory that may not be addressed randomly.
2. memory that may only be read from.
3. real address mode memory.
4. resident operating system memory.
A light emitting diode will light when:
1. the gate is turned on

Associate

Practice Exam 2