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8.33 meters is the full wavelength in air for what RF frequency? - correct answer ✔✔36 MHz Decimal 164 would appear as what in binary? - correct answer ✔✔ 10100100 A resistor has color stripes yellow, violet, violet, silver. It is? - correct answer ✔✔470 MegOhm +/- 10% What is the total capacitance of three capacitors valued at 100uf, 100uf and 50uf when connected in series? - correct answer ✔✔25 pf What is the ripple frequency of a full wave single phase bridge rectifier operated at 60 Hz? - correct answer ✔✔120 Hz What emits a voltage when heated or cooled? - correct answer ✔✔Thermocouple Adding the binary numbers 101011 and 001110 will give you what result? - correct answer ✔✔ 111001 A component that reduces in resistance as it is heated. - correct answer ✔✔A negative temperature coefficient thermistor An autotransformer - correct answer ✔✔has a single winding A dual trace oscilloscope differs from a single trace in that only the dual trace scope: - correct answer ✔✔alternates sweeps If an RF signal Voltage is reduced by 6db it is then : - correct answer ✔✔half the original size
Applying positive voltage to the P end and negative to the N end of a germanium diode: - correct answer ✔✔will forward bias it You would probably prefer a digital VOM over an ordinary analog meter: - correct answer ✔✔for most accuracy You should expect the video amplifier in a radar or TV receiver to have a frequency response of: - correct answer ✔✔0-6 MHzd The radio communication mode that utilizes the basic frequency and one of the side bands: - correct answer ✔✔is called "SSB" When using fiber optic to transfer a signal, the light must: - correct answer ✔✔enter the "cone of acceptance" The energy stored in a coil is measured in: - correct answer ✔✔Henrys The telephone communication term "Cellular" refers to: - correct answer ✔✔small geographic areas covered by each base station Integrated circuit failures often exhibit: - correct answer ✔✔open or short conditions Which of these would you normally choose to cause an LED to light? - correct answer ✔✔3 VDC A capacitor (3/8"x1/8" ceramic or mica) marked 47K is: - correct answer ✔✔47 pf +/- 10% A "digital storage oscilloscope": - correct answer ✔✔uses micro processing and memory to allow close analysis of signal. Carbon microphones are much like variable: - correct answer ✔✔resistors
If a class A differential amplifier is using only one of its two possible inputs, what will the output shape be? - correct answer ✔✔Exactly the same as the one input Voltage is: - correct answer ✔✔Potential difference between two points What is a term describing many op-amp circuits? - correct answer ✔✔inverting The gain of an op-amp is directly, but inversely, related to bandwidth as input frequency increases: - correct answer ✔✔Always The audio detector circuit in an AM radio most commonly is a: - correct answer ✔✔diode A differential amplifier with two identical in-phase signals on the inputs will have an output of: - correct answer ✔✔zero A fuse which has its fusible wire wrapped around an insulator is: - correct answer ✔✔Slo-blo type fuse The power transformer in a power supply: - correct answer ✔✔Might step voltages up or down Which of the below would be considered "basic" components of a non switching power supply? - correct answer ✔✔Filter, regulator, rectifier, transformer The average of a full sine wave rectified voltage is : - correct answer ✔✔.637 X Peak The ripple frequency for a half wave rectifier operating from 60 Hz electrical power is: - correct answer ✔✔60 HZ The effective voltage of a 100v Peak-to-peak sine wave is: - correct answer ✔✔35.35 VAC
A pi filter is an inductor with: - correct answer ✔✔A capacitor at each end to common An inductor opposes any change in: - correct answer ✔✔current A capacitor opposes any change in: - correct answer ✔✔voltage A capacitor will charge to what percent of full charge in one RC time? - correct answer ✔✔63. Moving one plate of a capacitor further away from the other will: - correct answer ✔✔decrease capacitance The fact that an inductor opposes any change in current is true of: - correct answer ✔✔AC and DC signals If you increase the value of a capacitor, the capacitive reactance will: - correct answer ✔✔decrease In checking a capacitor to see if it is really shorted, open or leaky: - correct answer ✔✔you would use the highest ohm meter range. The capacitor in a power supply capacitive filter: - correct answer ✔✔Is in parallel with the load The time required to discharge a capacitor depends on the: - correct answer ✔✔combination of LRC across its terminals. With a given filter type, pure filtering is easiest with: - correct answer ✔✔High frequencies A power supply whose output voltage does not change whether the load is light or heavy would have what percent of regulation? - correct answer ✔✔ 0
What is a reference antenna that all other antennas with gain are compared to? - correct answer ✔✔dipole A high frequency antenna is than a low frequency one. - correct answer ✔✔is shorter Standing waves on a transmission cable: - correct answer ✔✔can be caused by poor termination Sideband frequencies are produced when an radio carrier frequency is: - correct answer ✔✔modulated Doubling the power in a transmitter output is a: - correct answer ✔✔3 db gain 0 db is what level of received TV signal? - correct answer ✔✔1000 microVolts A byte is: - correct answer ✔✔8 bits In a 3 input AND gate: - correct answer ✔✔3 input must be high for a high output An LCD operates by polarizing the light through filters. The fluid rotates the light: - correct answer ✔✔ 90 degrees To test an SCR with an ohmmeter. - correct answer ✔✔with + to anode and - to cathode, short gate and anode together Using the Rx100 range and testing between the source and drain of an N channel JFET: - correct answer ✔✔readings should be equal in both directions With + voltage to drain or source and a - voltage to the gate on an N channel JFET, internal resistance of the JFET will be: - correct answer ✔✔High Which is least likely to cause ESD damage to MOSFET - correct answer ✔✔flux
A logic probe: - correct answer ✔✔indicates high and low voltage conditions In a typical electrical generator a small DC voltage applied to the field windings: - correct answer ✔✔is able to control the output level of the generator When working with and testing lead acid batteries - correct answer ✔✔Always wear eye protection and never cause a spark Audio signals, such as the output from DVD players, satellite receivers and preamplifers, usually are of what amplitude for input to a TV, modulator or other equipment? - correct answer ✔✔1 voltage peak to peak Which of these signal parameters does a spectrum analyzer show? - correct answer ✔✔Magnitude and frequency Permanent, non-volatile, non removable data storage in a computer is: - correct answer ✔✔ROM What should be used first to clean a corroded plated soldering iron tip? - correct answer ✔✔flux, cloth and heating When soldering high voltage connections: - correct answer ✔✔Leave the terminal with a smooth and rounded covering of solder Class AB operation of an audio amplifier means that current flows through the active device(tube, transistor,FET,IC) for how many degrees of the input signal wave? - correct answer ✔✔more than 180 but less then 360 A track on a computer disk is: - correct answer ✔✔divided into sectors A PC has conventional RAM and ROM memory area(in a PC it is 0 to 640 kilobytes); upper memory area(640 kilobytes to 1 meg) and extended memory area(above 1 meg). What other names for internal memory types do PCs have? - correct answer ✔✔Tape Drive
The gain of an op-amp connected as an inverting amplifier is determined by the external - correct answer ✔✔feedback and input resistors Which propagation condition would be significant for a UHF signal to be received at a distance of 500 miles? - correct answer ✔✔Tropospheric ducting A three input NAND has two low inputs and one high input. The output is: - correct answer ✔✔High Which of these would be considered a component of a "basic" power supply? - correct answer ✔✔diode rectifier A "Video Signal" is defined as: - correct answer ✔✔baseband including visual information You are servicing a power supply and have disconnected power. It has several 250 uf capacitors connected in parallel. To avoid shock these capacitors: - correct answer ✔✔Should be discharged to chassis ground, through a suitable resistor A schematic used in electronic: - correct answer ✔✔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 high voltage power source by: - correct answer ✔✔draining thru a large value resistor to chassis ground Which of these would be an important electrical consideration in the use of a transformer? - correct answer ✔✔The operating frequency If a 12v product is dissipating 50w, how much load resistance does the device represent? - correct answer ✔✔2.9 ohms An "audio signal" is defined as: - correct answer ✔✔frequencies in the 20Hz to 15000Hz range What will cause a generator to produce DC voltage rather then AC? - correct answer ✔✔the commutator
You suspect the unit has an internal short. To prevent further damage when you apply power, you should: - correct answer ✔✔insert a low resistance high wattage(100ohm, 10w) resistor in series with the power input. A ripple counter: - correct answer ✔✔Is two or more logical flip-flops connected sequentially with the input pulses toggling the first one When voltage is applied to a capacitor: - correct answer ✔✔current is maximum at first, then reduces as the capacitor becomes charges. An electrolytic capacitor in series between the power transformer and the rectifiers in a power supply: - correct answer ✔✔is part of a voltage doubler circuit Information travels through optic fiber via the flow of: - correct answer ✔✔photons You would most likely prefer an analog VOM over a DMM for: - correct answer ✔✔accuracy Which of these circuits would most likely use a zener diode? - correct answer ✔✔a power regulator A block in a digital diagram is called a NOR. Which is true? - correct answer ✔✔It is a NOT OR or Inverted OR Which of these statements is most true relating to schematic diagrams of electronic devices? - correct answer ✔✔They represent signal paths In personal computer technology, ROM indicates: - correct answer ✔✔memory that may only be read from A light emitting diode will light when: - correct answer ✔✔It is forward biased. A zener diode is rated 6.3V. This tells you: - correct answer ✔✔it conducts to limit the voltage across it to 6.3V
Which of these is a good indication of the quality of an analog meter? - correct answer ✔✔The ohms per volt rating The vertical axis of an oscilloscope display is also called the: - correct answer ✔✔Y axis If you increase the value of an inductor, the inductive reactance will: - correct answer ✔✔increase Which would least likely be a high-voltage(above 1000V) capacitor? - correct answer ✔✔electrolytic The rechargeable cell currently used in many consumer portable products would be: - correct answer ✔✔Lithium-ion A solid-state regulator: - correct answer ✔✔Varies conduction to maintain a level output voltage A current-carrying conductor is placed in a magnetic field perpendicular to the lines of flux. It tends to move in what direction to the force of magnetic lines of flux, as determined by Flemings left-hand rule. - correct answer ✔✔an opposite The antenna used to compare the gain of other antennas is called a: - correct answer ✔✔dipole The component that effectively becomes a short when turned on, and is turned off by disconnecting the path from the anode to cathode is the: - correct answer ✔✔silicon controlled rectifier Which of these terms would you most expect to see when referring to types of resistors? - correct answer ✔✔metal film "microwave" as used in radio electronics, refers to: - correct answer ✔✔1 GHz - 100 GHz radio frequencies A differential amplifier whose two input signals are equal, but 180 degrees out of phase, will have an - correct answer ✔✔maximum output signal
Which of these can be used to control the output level of a generator? - correct answer ✔✔small DC voltage applied to the field winding Impedance(Z, in ohms) includes: - correct answer ✔✔Resistance, capacitive reactance and inductive reactance The velocity factor in an RF transmission line is determined by: - correct answer ✔✔the dielectric material between the center conductor and shield A fuse, marked 250V, 650 ma can be used in circuits with an "open-fuse" supply voltage of: - correct answer ✔✔125 volts A thermistor: - correct answer ✔✔changes resistance with temperature When a transformer is designed, what most determines the output voltage from the secondary? - correct answer ✔✔The ratio of primary to secondary turns Adding armature windings in parallel to a generator's existing windings: - correct answer ✔✔improves its voltage stability A 10W signal is received at 5W. How many dB loss? - correct answer ✔✔3 dB loss It is desired to raise the power to a speaker from 15W to 30. This is a: - correct answer ✔✔3dB increase Which of these IC or semiconductor devices normally requires the most careful handling to avoid damage by static electricity? - correct answer ✔✔CMOS Which of these components most closely compares to the output of a solar cell? - correct answer ✔✔A NiCad battery Three series inductors have values of 20mh, 30mh and 40mh respectively total inductance is: - correct answer ✔✔90mh
In a series tuned circuit, to increase the resonant frequency, you would need to: - correct answer ✔✔decrease the inductance A mosfet: - correct answer ✔✔amplifies signal voltage variations Torroid cones are used in transformers for: - correct answer ✔✔concentrating the magnetic lines of flux A PLL or phase locked loop circuit, contains a VCO, or voltage controlled oscillator. The output of the VCO is an: - correct answer ✔✔AC changing frequency signal A variable capacitor depends on: - correct answer ✔✔the plate separation being adjustable While anode and cathode voltages are maintained the gate level in an SCR drops below the trigger point. What happens? - correct answer ✔✔The SCR stays on The combination of resistance and reactance which restricts the flow of alternating current is called: - correct answer ✔✔Impedance The output of a thermocouple would most likely be measured in: - correct answer ✔✔millivolts The Z axis on an oscilloscope is: - correct answer ✔✔intensity When soldering transistor or IC chip legs. What should be used to prevent overheating of the small discrete components/ - correct answer ✔✔heat sink clip Which of the below would normally be used for the core of a transformer? - correct answer ✔✔Ferrite The '1' in binary number 100000 carries a weight of: - correct answer ✔✔ 32 You would choose an LCD if you needed: - correct answer ✔✔a low current digital display
Germanium diodes: - correct answer ✔✔normally drop about .3V with forward current RF signal propagation that is normally considered "live of sight" would be: - correct answer ✔✔UHF
