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Amateur Radio Question PoolsNew! View the differences between the 2008 Extra question pool and the previous pool. Canadian Advanced Qualification Question PoolPrev 1 2 3 4 5 6 7 NextA-003-01-01 What is the easiest amplitude dimension to measure by viewing a pure sine wave on an oscilloscope? Peak voltage RMS voltage Average voltage A-003-01-02 What is the RMS value of a 340 volt peak-to-peak pure sine wave? 240 volts 300 volts 120 volts A-003-01-03 What is the equivalent to the RMS value of an AC voltage? The AC voltage causing the same heating of a given resistor as a DC voltage of the same value The DC voltage causing the same heating of a given resistor as the peak AC voltage The AC voltage found by taking the square root of the average AC value A-003-01-04 If the peak value of a 100 Hz sinusoidal waveform is 20 volts, the RMS value is: 7.07 volts 16.38 volts 14.14 volts A-003-01-05 In applying Ohm's law to AC circuits, current and voltage values are: average values times 1.414 none of the proposed answers peak values times 0.707 A-003-01-06 The effective value of a sine wave of voltage or current is: 70.7% of the maximum value 100% of the maximum value 63.6% of the maximum value A-003-01-07 AC voltmeter scales are usually calibrated to read: instantaneous voltage RMS voltage average voltage A-003-01-08 An AC voltmeter is calibrated to read the: average value effective value peak value A-003-01-09 Which AC voltage value will produce the same amount of heat as a DC voltage, when applied to the same resistance? The RMS value The peak value The peak-to-peak value A-003-01-10 What is the peak-to-peak voltage of a sine wave that has an RMS voltage of 120 volts? 169.7 volts 204.8 volts 339.5 volts A-003-01-11 A sine wave of 17 volts peak is equivalent to how many volts RMS? 12 volts 34 volts 8.5 volts A-003-02-01 The power supplied to the antenna transmission line by a transmitter during an RF cycle at the highest crest of the modulation envelope is known as: mean power carrier power full power A-003-02-02 To compute one of the following, multiply the peak- envelope voltage by 0.707 to obtain the RMS value, square the result and divide by the load resistance. Which is the correct answer? ERP PEP power factor A-003-02-03 Peak-Envelope Power (PEP) for SSB transmission is: multiplied by 0.707, squared and divided by the load resistance peak-voltage multiplied by peak current equal to the rms power a hypothetical measurement A-003-02-04 The formula to be used to calculate the power output of a transmitter into a resistor load using a voltmeter is: P = E^2/R P = EI cos 0 P = IR A-003-02-05 How is the output Peak-Envelope Power of a transmitter calculated, if an oscilloscope is used to measure the Peak- Envelope Voltage across a dummy resistive load? PEP = Peak-Envelope Power PEV = Peak-Envelope Voltage Vp = peak-voltage RL = load resistance PEP = [(Vp)(Vp)] / (RL) PEP = (Vp)(Vp)(RL) PEP = [(1.414 PEV)(1.414 PEV)] / RL A-003-02-06 What is the output PEP from a transmitter if an oscilloscope measures 200 volts peak-to-peak across a 50-ohm dummy load connected to the transmitter output? 100 watts 1000 watts 200 watts A-003-02-07 What is the output PEP from a transmitter if an oscilloscope measures 500 volts peak-to-peak across a 50-ohm dummy load connected to the transmitter output? 625 watts 2500 watts 500 watts A-003-02-08 What is the output PEP of an unmodulated carrier transmitter if a wattmeter connected to the transmitter output indicates an average reading of 1060 watts? 1500 watts 1060 watts 530 watts A-003-02-09 What is the output PEP from a transmitter, if an oscilloscope measures 400 volts peak-to-peak across a 50 ohm dummy load connected to the transmitter output? 200 watts 600 watts 1000 watts A-003-02-10 What is the output PEP from a transmitter, if an oscilloscope measures 800 volts peak-to-peak across a 50 ohm dummy load connected to the transmitter output? 1600 watts 6400 watts 3200 watts A-003-02-11 An oscilloscope measures 500 volts peak-to-peak across a 50 ohm dummy load connected to the transmitter output during unmodulated carrier conditions. What would an average-reading power meter indicate under the same transmitter conditions? 884 watts 442 watts 625 watts A-003-03-01 What is a dip meter? A marker generator A variable frequency oscillator with metered feedback current A field-strength meter A-003-03-02 What does a dip meter do? It measures field strength accurately It measures frequency accurately It gives an indication of the resonant frequency of a circuit A-003-03-03 What two ways could a dip meter be used in an amateur station? To measure antenna resonance and impedance To measure antenna resonance and percentage modulation To measure resonant frequency of antenna traps and percentage modulation A-003-03-04 A dip meter supplies the radio frequency energy which enables you to check: the calibration of an absorption-type wavemeter the impedance mismatch in a circuit the adjustment of an inductor A-003-03-05 A dip meter may not be used to: align transmitter-tuned circuits determine the frequency of oscillations align receiver-tuned circuits A-003-03-06 The dial calibration on the output attenuator of a signal generator: reads twice the true output when the attenuator is properly terminated reads half the true output when the attenuator is properly terminated reads accurately only when the attenuator is properly terminated A-003-03-07 What is a signal generator? A high-stability oscillator which can produce a wide range of frequencies and amplitudes A low-stabilty oscillator used to inject a signal into a circuit under test A high-stability oscillator which generates reference signals at exact frequency intervals A-003-03-08 A dip meter: may be used only with series tuned circuits accurately measures frequencies should be loosely coupled to the circuit under test A-003-03-09 A dip meter is: an RF amplifier tuning meter a battery electrolyte level gauge a variable frequency oscillator with metered feedback current A-003-03-10 The dip meter is most directly applicable to: digital logic circuits parallel tuned circuits series tuned circuits A-003-03-11 Which of the following IS NOT a factor affecting the frequency accuracy of a dip meter? stray capacity over coupling transmitter power output A-003-04-01 What does a frequency counter do? It makes frequency measurements It generates broad-band white noise for calibration It produces a reference frequency A-003-04-02 What factors limit the accuracy, frequency response and stability of a frequency counter? Number of digits in the readout, speed of the logic, and time base stability Number of digits in the readout, external frequency reference and temperature coefficient of the logic Time base accuracy, speed of the logic, and time base stability A-003-04-03 How can the accuracy of a frequency counter be improved? By using faster digital logic By improving the accuracy of the frequency response By increasing the accuracy of the time base A-003-04-04 If a frequency counter with a time base accuracy of +/- 0.1 PPM reads 146 520 000 Hz, what is the most that the actual frequency being measured could differ from that reading? "PPM = parts per million" 1.4652 Hz 1.4652 kHz 14.652 Hz A-003-04-05 If a frequency counter, with a time base accuracy of 10 PPM reads 146 520 000 Hz, what is the most the actual frequency being measured could differ from that reading? "PPM = parts per million" 146.52 Hz 146.52 kHz 1465.2 kHz A-003-04-06 The clock in a frequency counter normally uses a: self-oscillating Hartley oscillator mechanical tuning fork free-running multivibrator A-003-04-07 The frequency accuracy of a frequency counter is determined by: type of display used in the counter the characteristics of the internal timebase generator the number of digits displayed A-003-05-01 If a 100 Hz signal is fed to the horizontal input of an oscilloscope and a 150 Hz signal is fed to the vertical input, what type of pattern should be displayed on the screen? A looping pattern with 3 horizontal loops, and 2 vertical loops An oval pattern 100 mm wide and 150 mm high A looping pattern with 100 horizontal loops and 150 vertical loops A-003-05-02 What factors limit the accuracy, frequency response and stability of an oscilloscope? Accuracy of the time base and the linearity and bandwidth of the deflection amplifiers Accuracy and linearity of the time base and tube face voltage increments Tube face voltage increments and deflection amplifier voltages A-003-05-03 How can the frequency response of an oscilloscope be improved? By increasing the horizontal sweep rate and the vertical amplifier frequency response By increasing the vertical sweep rate and the horizontal amplifier frequency response By using triggered sweep and a crystal oscillator for the timebase A-003-05-04 You can use an oscilloscope to display the input and output of a circuit at the same time by: measuring the input on the X axis and the output on the Z axis utilizing a dual trace oscilloscope measuring the input on the Y axis and the output on the X axis A-003-05-05 An oscilloscope cannot be used to: measure DC voltage determine FM carrier deviation determine the amplitude of complex voltage wave forms A-003-05-06 The bandwidth of an oscilloscope is: indirectly related to screen persistence the highest frequency signal the scope can display a function of the time-base accuracy A-003-05-07 When using Lissajous figures to determine phase differences, an indication of zero or 180 degrees is represented on the screen of an oscilloscope by: an ellipse a diagonal straight line a circle A-003-05-08 A 100-kHz signal is applied to the horizontal channel of an oscilloscope. A signal of unknown frequency is applied to the vertical channel. The resultant wave form has 5 loops displayed vertically and 2 loops horizontally. The unknown frequency is: 50 kHz 40 kHz 30 kHz A-003-05-09 What item of test equipment contains horizontal and vertical channel amplifiers? An oscilloscope An ammeter An ohmmeter A-003-05-10 What is the best instrument to use to check the signal quality of a CW or single-sideband phone transmitter? An oscilloscope A signal tracer and an audio amplifier A field-strength meter A-003-05-11 What signal source is connected to the vertical input of an oscilloscope when checking the quality of a transmitted signal? the IF output of a monitoring receiver the audio input of the transmitter the RF output of the transmitter A-003-06-01 A meter has a full-scale deflection of 40 microamps and an internal resistance of 96 ohms. You want it to read 0 to 1 mA. The value of the shunt to be used is: 16 ohms 4 ohms 40 ohms A-003-06-02 A moving-coil milliammeter having a full-scale deflection of 1 mA and an internal resistance of 0.5 ohms is to be converted to a voltmeter of 20 volts fullscale deflection. It would be necessary to insert a: series resistance of 19 999.5 ohms shunt resistance of 19 999.5 ohms shunt resistance of 19.5 ohms A-003-06-03 A voltmeter having a range of 150 volts and an internal resistance of 150 000 ohms is to be extended to read 750 volts. The required multiplier resistor would have a value of: 750 000 ohms 1 200 000 ohms 600 000 ohms A-003-06-04 The sensitivity of an ammeter is an expression of: the resistance of the meter the loading effect the meter will have on a circuit the value of the shunt resistor A-003-06-05 Voltmeter sensitivity is usually expressed in ohms per volt. This means that a voltmeter with a sensitivity of 20 kilohms per volt would be a: 1 milliampere meter 50 milliampere meter 100 milliampere meter A-003-06-06 The sensitivity of a voltmeter, whose resistance is 150 000 ohms on the 150- volt range, is: 1000 ohms per volt 10 000 ohms per volt 150 ohms per volt A-003-06-07 The range of a DC ammeter can easily be extended by: changing the internal inductance of the meter connecting an external resistance in parallel with the internal resistance changing the internal capacitance of the meter to resonance A-003-06-08 What happens inside a multimeter when you switch it from a lower to a higher voltage range? Resistance is added in series with the meter Resistance is reduced in parallel with the meter Resistance is added in parallel with the meter A-003-06-09 How can the range of an ammeter be increased? By adding resistance in series with the circuit under test By adding resistance in parallel with the circuit under test By adding resistance in series with the meter A-003-06-10 Where should an RF wattmeter be connected for the most accurate readings of transmitter output power? At the transmitter output connector One-half wavelength from the antenna feed point At the antenna feed point A-003-06-11 At what line impedance do most RF wattmeters usually operate? 100 ohms 300 ohms 50 ohms |
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