FCC General Radiotelephone Operator License (GROL) Element 3 Practice Test

These questions are part of the practice quiz. Start practicing

• What are the elements of a unijunction transistor?
• What is an advantage of using a trap antenna?
• Which voltage drop at the end of the last segment satisfies NMEA 2000 network cabling plans?
• What components make up a typical three-terminal regulator?
• What tolerance off of plumb should a single base station radio rack be installed?
• What is the effect of selecting the USA-INT control on channels that are normally duplex?
• To lower the resonant frequency of a Hertz antenna, you would place an inductance in series with the antenna.
• The resonant frequency of a Hertz antenna can be lowered by:
• What is the magnitude of the impedance of a series circuit with a 0.1 microhenry inductor and a 30-ohm resistor at 5 MHz?
• What does a coupling capacitor do in a circuit?
• All directions associated with a VOR station are related to which reference?
• As antenna gain increases, beamwidth tends to:
• What frequencies are present at the output of a mixer?
• Which device is typically used to monitor transmitter frequency and modulation and to check receiver sensitivity and distortion?
• Which device is used to locate faults along a transmission line by observing reflections?
• Which oscilloscope stage primarily determines the maximum frequency response of the instrument?
• How many degrees are there in one complete sine wave cycle?
• Which spread spectrum method uses spreading with a pseudo-random code to spread the spectrum?
• Why is the value of the radiation resistance of an antenna important?
• NAVTEX MSI broadcasts are received using which mode?
• After two time constants, the capacitor in an RC circuit is charged to what percentage of the supply voltage?
• In polar coordinates, what is the impedance of a network consisting of a 300-ohm-reactance capacitor, a 600-ohm-reactance inductor, and a 400-ohm resistor, all connected in series?
• A string of 12 NiCd cells connected in series produces approximately how many volts?
• In rectangular coordinates, what is the impedance of a network consisting of a 0.1-microhenry inductor in series with a 30-ohm resistor at 5 MHz?
• An oscilloscope can be used to perform all of the following except which?
• Before ground testing an aircraft RADAR, the operator should:
• What is the approximate ratio of peak envelope power to average power during normal voice modulation peak in a single-sideband phone signal?
• In an ideal transformer, the secondary current is inversely proportional to the turns ratio Ns/Np. Which option reflects this statement?
• Which emission designation is commonly used for SSB voice transmissions?
• Shipboard RADAR is most commonly operated in which band?
• What is the primary purpose of the first IF amplifier stage in a receiver?
• Phase 2 P25 radios utilize which audio codec?
• Which network provides the greatest harmonic suppression?
• In mixer operation, which term describes the response where an unwanted signal at the image frequency also produces the same IF?
• What is the time constant in an RC circuit?
• What is the typical effect of placing a low-pass filter in the antenna feed line of a transmitter?
• What fundamental requirement must be met for a circuit to sustain oscillations?
• What frequency is used for ATCRBS interrogation signals?
• For a circuit with a square wave input, what would be the output?
• Which statement correctly describes the control of a switching regulator’s output?
• At the ends of a half-wave antenna, compared to the remainder of the antenna, what are the voltage and current?
• What is the GPS satellite orbital altitude?
• Which modulation type can involve frequency hopping of a single carrier or multiple simultaneous carriers?
• What is the orbital altitude of INMARSAT satellites?
• In a pulse-position modulation system, what parameter does the modulating signal vary?
• What is the voltage across the lamp in the circuit described in the first question?
• What is the name of the type of modulation in which the modulating signal varies the duration of the transmitted pulse?
• If the current through a resistor doubles, the voltage across it changes how?
• In a three-terminal regulator, which component provides the stable reference voltage?
• What is the term used to express the amount of electrical energy stored in an electrostatic field?
• Which statement best describes the process of intermodulation interference when two signals mix in a transmitter chain?
• Name two types of spread spectrum systems used in most RF communications applications?
• What happens to the beamwidth of an antenna as the gain is increased?
• Two 470 kΩ resistors in series yield an equivalent resistance of?
• Which two navigation aids form the paired channel that DME systems auto-tune to?
• Which precaution is recommended before powering up an aircraft radar transmitter for testing?
• What is the name of the semiconductor memory IC whose digital data can be written or read, and whose memory word address can be accessed randomly?
• In a circuit where a dashed line indicates a place to insert a small variable capacitor, inserting the capacitor would result in which outcome?
• How should the signal from a Search And Rescue RADAR Transponder appear on a radar screen?
• Which instrument is commonly used to monitor frequency, modulation, check receiver sensitivity, distortion, and to generate audio tones?
• What is the frequency range of the localizer beam system used by aircraft to find the centerline of a runway during an Instrument Landing System (ILS) approach to an airport?
• Which relation expresses V_peak in terms of V_RMS for a sine wave?
• The most the actual transmit frequency could differ from a reading of 462.1 MHz on a frequency counter with time-base accuracy ±0.1 ppm?
• What does PPS stand for in radar terminology?
• What is the deviation ratio for an FM signal with a maximum deviation of ±7.5 kHz and a maximum modulation rate of 3.5 kHz?
• Which of the following codes has gained the widest acceptance for exchange of data from one computer to another?
• What will occur when a non-linear amplifier is used with a single-sideband phone transmitter?
• In an RC circuit, the time constant is defined as?
• How can an FM-phone signal be produced in a transmitter?
• In SITOR ARQ operation, which method ensures reliability?
• What is the effective radiated power of a repeater with 100 watts transmitter power output, 4 dB feedline loss, 3 dB duplexer and circulator loss, and 7 dB antenna gain?
• What frequency band is used by a SART?
• Which factor primarily determines the maximum forward current capability of a junction diode?
• Which SWR value indicates a perfect match between transmission line and load?
• Which statement describes an advantage of a constant-k RF filter?
• How can ferrite beads be used to suppress ignition noise? Install them
• Which list shows descending conductivity with correct order?
• Which device stores a single bit and has two stable states?
• What does the photoconductive effect in crystalline solids produce a noticeable change in?
• Which modulation technique varies the duration of a fixed-width pulse to encode information?
• Which of the following represents the best standing wave ratio (SWR)?
• In a circuit with the given DC input voltages, which of the following could be the output voltage?
• How many flip-flops are required to divide a signal frequency by 4?
• In VOR navigation, what term describes a line extending from the VOR station in a specific magnetic direction?
• A time-domain reflectometer (TDR) is formed by combining which two instruments?
• What is the time constant of a circuit consisting of two 100-microfarad capacitors and two 470-kilohm resistors all in series?
• What is the phase angle of the impedance for a network formed by a 400-ohm inductor reactance in parallel with a 300-ohm resistor?
• During a two-tone linearity test of an SSB transmitter, which instrument is commonly used to view the output waveform?
• If a shunt motor running with a load has its shunt field opened, how would this affect the speed of the motor?
• Which code contains the widely used standard for text data interchange among computers?
• Which oscillator configuration is commonly used in VFOs because of its stability?
• The unit PPS used in radar terminology stands for what?
• What is meant by the term radiation resistance of an antenna?
• Which characteristic distinguishes a Butterworth filter?
• Nitrogen is placed in transmission lines to:
• Digital signal processing (DSP) of RADAR signals (compared with analog) causes:
• What is the effective radiated power of a repeater with 75 watts transmitter power output, 4 dB feedline loss, 3 dB duplexer and circulator loss, and 10 dB antenna gain?
• In a circuit with the given DC input voltages, what would the output voltage be?
• What is the term for a receiver's ability to reject adjacent unwanted signals near the desired frequency?
• Which circuit might contain an SCR?
• What is the deviation ratio for an FM signal with a maximum frequency deviation of ±5 kHz and a maximum modulation rate of 3 kHz?
• In a negative-logic circuit, what level is used to represent a logic 0?
• The vertical axis of a spectrum analyzer indicates which quantity?
• Which statement best describes the fuse issue likely causing apparent low voltage on marine SSB transmitting?
• MOSFETs are manufactured with THIS protective device built into their gate to protect the device from static charges and excessive voltages:
• What is the frequency range of aircraft VHF communications?
• For a 3 horsepower, 100 V DC motor that is 85% efficient, what is the input power in watts?
• VOR azimuth information is referenced to which magnetic reference?
• What is meant by the term noise figure of a communications receiver?
• What frequencies do GPS signals transmit on?
• In addition to duplicating the functions of a mode C transponder, an aircraft's mode S transponder can also provide:
• What describes a diode junction that is forward biased?
• What VHF channel is assigned for distress and calling?
• What is a 1/2 digit on a DMM?
• In NMEA 2000, a load equivalent number (LEN) of 1 corresponds to how much current?
• A perfect (no loss) coaxial cable has 7 dB of reflected power when the input is 5 watts. What is the output of the transmission line?
• What type of wire connects an SSB automatic tuner to an insulated backstay?
• The bandwidth of an antenna shortened with loading coils:
• What is the piezoelectric effect?
• How should shielding be grounded on an NMEA 0183 data line?
• At what aggregate power level is an MPE (Maximum Permissible Exposure) study required?
• During a VOR variable signal rotation of 30 revolutions per second, what is the rate in revolutions per minute?
• Which of the following is the SI unit of energy?
• Which term best describes the amount of work done or energy transferred when a force causes displacement?
• Which metal object may be least affected by galvanic corrosion when submerged in saltwater?
• An AC ammeter indicates which type of current value?
• What does MPE stand for in RF safety terminology?
• Which statement correctly defines the RMS value of an AC voltage?
• In which frequency band does a search and rescue transponder operate?
• When observing the output of a direct digital synthesizer, which type of spectral content is typically present?
• Which statement about RAM (Random-Access Memory) is true?
• What is the approximate footprint diameter of Iridium spot beams?
• In a positive-logic circuit, which level is used to represent a logic 0?
• What is the main underlying operating principle of the Very-high-frequency Omnidirectional Range (VOR) aircraft navigational system?
• What type of encoding is used by a Mode C transponder transmission to ATCRBS ground stations?
• Power dissipated by a 12V source across a 4-ohm resistor?
• In a microprocessor, what is the meaning of the term 'ALU'?
• If a 10-ohm resistor has 2 A of current, what is the voltage across it?
• Which measurement describes the rate at which electrical energy is consumed or produced?
• Given a power supply with a no load voltage of 12 volts and a full load voltage of 10 volts, what is the percentage of voltage regulation?
• What is a bistable multivibrator circuit commonly named?
• A receiver selectivity of 2.4 kHz in the IF circuitry is optimum for what type of signals?
• What type of wire would connect an SSB automatic tuner to an insulated backstay?
• In an FM-phone signal, what is the term for the maximum deviation divided by the maximum audio modulating frequency?
• Aviation services use predominantly ____ microphones.
• What is the magnitude of the impedance of a series network consisting of a 400-ohm resistor, a 600-ohm inductor reactance, and a 300-ohm capacitor reactance?
• What is the maximum DC or RMS voltage that may be connected across a 20 watt, 2000 ohm resistor?
• What is the principal characteristic of a tunnel diode?
• What is a balanced modulator?
• What is the main function of the COSPAS-SARSAT satellite system?
• What is a common method of programming portable or mobile radios?
• At the resonant frequency, which statement about capacitive and inductive reactances is true?
• Which statement about SITOR communications is true?
• A 6-volt battery with 1.2 ohms internal resistance is connected across two 12-ohm bulbs in parallel. What is the total current drawn from the battery?
• What is a product detector?
• Which unit represents electric power in a circuit?
• The INMARSAT mini-M system is best described as what?
• What is the term used to refer to the condition where the signals from a very strong station are superimposed on other signals being received?
• What class of amplifier is distinguished by the presence of output throughout the entire signal cycle and the input never goes into the cutoff region?
• What measurement does the VOR use to determine an aircraft's azimuth relative to the station?
• For a circuit with a square wave input, what would be the output?
• What is the frequency range of the marker beacon system used to indicate an aircraft's position during an Instrument Landing System (ILS) approach to an airport's runway?
• A 12-volt, 50 Ah battery stores how many watt-hours?
• What circuit component must be connected in series to protect an LED?
• What is the standard scan rate for HF weather facsimile reception from shore stations in the 3 MHz to 23 MHz range?
• What color is the binder for pairs 51-75 in a 100-pair cable?
• Which network configuration provides the most effective harmonic suppression?
• What is the RMS value of a 340-volt peak-to-peak pure sine wave?
• In INMARSAT's regional configuration, which designation is at 178° E?
• The piezoelectric effect involves which of the following?
• A product detector uses which process to demodulate signals?
• In rectangular coordinates, what is the impedance of a network consisting of a 0.01-microfarad capacitor in parallel with a 300-ohm resistor at 50 kHz?
• Which of the 4 groups of metals listed below are the best low-resistance conductors?
• If a carrier frequency has a second harmonic, what frequency is it?
• Where along a half-wave antenna is the current minimum and the voltage maximum?
• A balanced modulator outputs which type of signal?
• Time constant of a circuit with two 100 µF capacitors and two 470 kΩ resistors in series is.
• Which device provides a highly accurate reference frequency for calibration purposes?
• What is the basic unit of electrical power?
• If a marine radiotelephone receiver uses 75 watts and a transmitter uses 325 watts, how long can they both operate before discharging a 50 ampere-hour, 12-volt battery?
• What integrated circuit device converts an analog signal to a digital signal?
• Maximum allowable frequency deviation for VHF marine radios is:
• In AC circuits, which statement correctly describes RMS value?
• What condition must exist for a circuit to oscillate?
• Intermodulation interference between two transmitters in close proximity can be reduced by which method?
• What is the characteristic of the current flow in a series R-L-C circuit at resonance?
• What is the maximum FM deviation for voice operation of a normal wideband channel on VHF and UHF?
• What does a two-tone test illustrate on an oscilloscope?
• What is the common method for determining the exact sensitivity specification of a receiver?
• Which of the following describes the INMARSAT satellite system designations for AOR-E, AOR-W, POR, and IOR?
• An optoisolator is built using which two key components?
• In radio receivers, selectivity primarily determines the ability to do what?
• If a radar PRF is 500 pulses per second, how many pulses occur in two seconds?
• A relay coil has 500 ohms resistance and operates on 125 mA. What value of resistance should be connected in series with it to operate from 110 V DC?
• What is the proper way to cut plastic wire ties?
• Which form describes Ohm's law in its simplest form?
• If a receiver mixes a 13.8 MHz VFO with a 14.255 MHz receive signal to produce a 455 kHz intermediate frequency signal, what type of interference will a 13.345 MHz signal produce in the receiver?
• Butterworth filters are designed to have what kind of response in their passband?
• What is the maximum exposure limit for microwave energy in mW per centimeter under U.S. Health Department regulations?
• Which of the following statements about SSB voice transmissions is correct?
• The rate that the transmitted VOR variable signal rotates is equivalent to how many revolutions per second?
• What is an L-network?
• Which device transmits the angular position of the antenna to the radar indicator?
• How many satellites are in the Iridium constellation and into how many orbital planes are they arranged?
• What is one way that voice is transmitted in a pulse-width modulation system?
• What makes Digital Coded Squelch work?
• What type of antenna is attached to a Mode C transponder installation and used to receive 1030 MHz interrogation signals from ATCRBS?
• What does the term 'DAC' refer to in a microprocessor circuit?
• To convert RMS voltage to peak voltage, what factor must be used?
• What factors should be considered when selecting an intermediate frequency?
• Which statement best describes the USA-INT function on duplex channels?
• In the same battery setup, with two 12-ohm lamps in parallel, what is the current through each lamp?
• When mixing a 200 MHz RF signal with a 150 MHz LO, which frequency would appear at the mixer output before filtering?
• In a circuit with a 6-volt battery having 1.2 ohms internal resistance feeding two 12-ohm lamps in series, what is the current through the circuit?
• The voltage produced in a receiving antenna is:
• Corrosion resulting from electric current flow between dissimilar metals is called:
• Which two performance aspects are typically considered when selecting an intermediate frequency?
• Which circuit is used to detect FM-phone signals?
• Which instrument would be the least effective for measuring the RF characteristics of a radio?
• What special type of diode is capable of both amplification and oscillation?
• Why must you never look directly into a fiber optic cable?
• Crest factor for a pure sine wave (ratio of peak to RMS) is approximately:
• A flip-flop circuit is a binary logic element with how many stable states?
• The Distance Measuring Equipment (DME) ground station has a built-in delay between reception of an interrogation and transmission of the reply to allow:
• A 1-watt, 10-volt Zener diode with the following characteristics: Imin = 5mA; Imax = 95 mA; and Z = 8 ohms, is to be used as part of a voltage regulator in a 20-volt power supply. Approximately what size current-limiting resistor would be used to set its bias to midpoint of its operating range?
• Good conductors with minimum resistance have what type of electrons?
• What is meant by the term back emf?
• What is the resonant frequency in an electrical circuit?
• For a target 25 miles away on the 25 mile range setting, what is the most appropriate pulse width and pulse repetition rate?
• What is the maximum deviation from the reading 462,100,000 Hz on a frequency counter with a time-base accuracy of ±1.0 ppm?
• What does DRAM stand for?
• An L-network consists of which two passive components?
• In a series R-L-C circuit at resonance, the current is:
• Which statement about infrared hazard with fiber optics is accurate?
• What is the expected observation about the two-tone SSB test result when the test is performed to assess linearity?
• What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?
• The RF power reading on a CDMA radio is not accurate on which type of meter?
• What are the three terminals of an SCR?
• What is an important factor in pulse-code modulation using time-division multiplex?
• What capacity in amperes does a storage battery need to be in order to operate a 50 watt transmitter for 6 hours? Assume a continuous transmitter load of 70% of the key-locked demand of 40 A, and an emergency light load of 1.5 A.
• What do the initials TTL stand for?
• When evaluating RF site exposure for sites with multiple transmitting antennas, antennas with more than _______% of the maximum permissible power density exposure limit must be included.
• ERP stands for what in RF exposure contexts?
• A 3 horsepower, 100 V DC motor is 85% efficient when developing its rated output. What is the current?
• To couple energy into and out of a waveguide use:
• An LED facing a photodiode in a light-tight enclosure is commonly known as a/an:
• How might two similar SCRs be connected to safely distribute the power load of a circuit?
• One time constant in an RC circuit corresponds to which percentage of the final value for the capacitor voltage?
• What is the name of the random-accessed semiconductor memory IC that must be refreshed periodically to maintain reliable data storage in its memory matrix?
• What type of antenna is used in an aircraft's Instrument Landing System (ILS) glideslope installation?
• What describes a transistor in cutoff?
• Which of the following logic gates will provide an active high out when both inputs are active high?
• Digital signal processing (DSP) of RADAR signals, compared with analog, causes:
• What is the name of the condition that occurs when signals from two transmitters mix and generate sum and difference frequencies?
• What is the purpose of a synchro transmitter and receiver?
• 3-76L3 What stage determines the maximum frequency response of an oscilloscope?
• Conductance takes place in a waveguide:
• In a regulator, what is the role of the sense resistor network?
• Which INMARSAT systems offer High Speed Data at 64/54 kbps?
• In the same circuit, what is the phase angle of the impedance?
• What is the main advantage of using an op-amp audio filter over a passive LC audio filter?
• In a two-tone SSB test, the tones used should be
• How is a frequency counter used?
• Most airborne DME systems automatically tune their transmitter and receiver frequencies to the paired channel. This pairing refers to which two navigation aids?
• Lines drawn from the VOR station in a particular magnetic direction are?
• In polar coordinates, what is the impedance of a network comprised of a 400-ohm- reactance inductor in parallel with a 300-ohm resistor?
• What CODEC is used in Phase 2 P25 radios?
• What limits maximum forward current in a junction diode?
• Which statement best describes spread-spectrum communication?
• Which statement best describes a switching electronic voltage regulator?
• A transmitter delivers 200 volts peak-to-peak across a 50-ohm load. What is the output peak envelope power?
• For a sinusoidal signal across a resistor, which expression correctly relates output power to peak-to-peak voltage Vpp and resistance R?
• What is the RMS value of a sine wave with a peak amplitude of 340 volts?
• Which statement about Iridium satellites is true?
• What does the DSP not do in a modern DSP radio?
• Which memory type must be refreshed periodically to maintain data?
• When a RADAR is being operated on the 1.5 mile range setting, what is the most appropriate pulse width and pulse repetition rate?
• If a 100-ohm resistor is connected across 200 volts, what is the current through the resistor?
• Which statement about satellite EPIRBs is true?
• What term describes a wide-bandwidth system in which the RF carrier varies according to a predetermined sequence?
• What is the term for the ratio between the largest tolerable receiver input signal and the minimum discernible signal?
• An excited 1/2 wavelength antenna produces:
• Which method is preferred for cleaning solder from plated-through circuit-board holes?
• Why is the Colpitts oscillator circuit commonly used in a VFO?
• Carson's rule for FM bandwidth is given by which expression?
• What is the primary purpose of an RF amplifier in a receiver?
• How many orbital planes do Iridium satellites use?
• What does it mean for a transistor to be fully saturated?
• In most radio systems, which statement best describes the purpose of the built-in self-test feature?
• When estimating receiver sensitivity via SINAD, which value is commonly used?
• In a forward-biased diode, what is the impedance?
• Which instrument is best for observing waveform shapes and timing in RF signals?
• In FM demodulation, which circuit converts frequency variations into a voltage?
• In a positive-logic circuit, what level is used to represent a logic 1?
• NAVTEX is true for MSI broadcasts?
• What is the main underlying operating principle of a Distance Measuring Equipment (DME) system used on aircraft?
• RF input to a mixer is 200 MHz and the local oscillator frequency is 150 MHz. What output would you expect to see at the IF output prior to any filtering?
• In an NMEA 2000 device, a load equivalence number (LEN) of 1 is equivalent to how much current consumption?
• What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?
• How might an installer verify correct GPS sentence to marine DSC VHF radio?
• To produce a single-sideband suppressed carrier transmission, it is necessary to ____ the carrier and to ____ the unwanted sideband.
• For current to flow in an NPN silicon transistor's emitter-collector path, the base must be:
• What is a frequency standard?
• Which statement best describes the operation of a Class A amplifier?
• PW, used in radar terminology, stands for which of the following?
• In INMARSAT's regional configuration, which designation is paired with 64.5° E as IOR?
• What occurs if the load is removed from an operating series DC motor?
• Which class of amplifier provides the highest efficiency?
• Two equal capacitors in series yield an equivalent capacitance of what fraction of a single capacitor?
• What is the total bandwidth of an FM phone transmission having a 5 kHz deviation and a 3 kHz modulating frequency?
• What is the second harmonic of an SSB frequency of 4146 kHz?
• Which condition can render INMARSAT-B communications impossible?
• In a pulse-width modulation system, what parameter does the modulating signal vary?
• In a direct digital synthesizer, what are the unwanted components on its output?
• How much gain should be used in the RF amplifier stage of a receiver?
• The class B amplifier output is present for what portion of the input cycle?
• What are the characteristics of an inverting operational amplifier (op-amp) circuit?
• An excited 1/2 wavelength antenna produces which fields?
• What is the purpose of a prescaler circuit?
• If the elapsed time for a RADAR echo is 62 microseconds, what is the distance to the object in nautical miles?
• What turns ratio does a transformer need in order to match a source impedance of 500 ohms to a load of 10 ohms?
• Which device is commonly used to prevent mutual interference between two transmitters in close proximity?
• Which of the following is NOT a precaution that should be taken to ensure the magnetron is not weakened?
• In a RL circuit with a 60-degree phase difference between voltage and current, what is the power factor?
• What will produce a magnetic field?
• What is the total voltage when 12 Nickel-Cadmium batteries are connected in series?
• Which instrument would be best for checking a TTL logic circuit?
• What type of signals are used to conduct an SSB two-tone test?
• What kind of input signal could be used to test the amplitude linearity of a single-sideband transmitter while viewing the output on an oscilloscope?
• Which function is performed by the pass element in a three-terminal regulator?
• Which instrument is used to measure the phase difference between two RF signals?
• Which VHF frequency range upper limit is used worldwide for aviation communications?
• In a software-defined transceiver, what is the quickest way for a technician to evaluate the radio's condition?
• For the parallel combination of a 0.01 µF capacitor and a 300-ohm resistor at 50 kHz, which value is closest to the real part of the impedance?
• In a 6-volt storage battery with an internal resistance of 0.01 ohm, a 6-volt, 3-watt lamp is connected. What current flows through the circuit?
• What is a characteristic of an OR gate?
• What are the principal frequencies that appear at the output of a mixer circuit?
• What is the description of an optocoupler?
• A transformer has a primary winding of 200 turns and a secondary winding of 500 turns. If 20 volts are applied to the primary, what is the expected secondary voltage?
• In RF terminology, the carrier deviation refers to the maximum shift in carrier frequency due to modulation. Which option best describes this?
• A 50 microampere meter movement has an internal resistance of 2,000 ohms. What applied voltage is required to indicate half-scale deflection?