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Advanced - Transmitters and receivers
Transmitters and receivers follows the A-003 section of the Canadian question bank.
66
Questions
6
Sibling Topics
- Pool
- Advanced
- Questions
- 66
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- Transmitters and receivers
- Region
- CA
Review by section order to build the topic framework first.
For regulatory and safety questions, prefer compliant and conservative actions.
For calculations, check units, multipliers, and approximations.
Topic Study Guide
This topic covers transmitter and receiver testing and measurement techniques for the Canadian Advanced Amateur Radio exam (A-003). Key areas include oscilloscope usage and waveform analysis, Peak-Envelope Power (PEP) and RMS calculations, applications of various test instruments (e.g., frequency counters, dip meters, signal generators), and extending the range of voltmeters and ammeters.
High-Yield Checks
- AC Voltage Conversions: Master the formulas converting between RMS, Peak, and Peak-to-Peak voltages, especially RMS = Peak × 0.707.
- PEP Calculations: Memorize the formula for calculating Peak-Envelope Power using Peak-Envelope Voltage (PEV) from an oscilloscope, ensuring PEV is converted to RMS before calculating power.
- Oscilloscope Applications and Limits: Know how to calculate unknown frequencies using Lissajous figures (Known Frequency × Horizontal Loops / Vertical Loops) and remember that scopes cannot directly measure FM deviation.
- Meter Range Extension: Understand that voltmeters require series multiplier resistors, while ammeters need parallel shunt resistors. Always subtract the meter's internal resistance in calculations.
Trap Patterns
- Voltage Concept Confusion: Forgetting to double the peak voltage for peak-to-peak calculations, or failing to convert peak voltage to RMS before calculating power.
- Inverting Lissajous Ratios: Incorrectly dividing vertical loops by horizontal loops when calculating unknown frequencies on an oscilloscope.
- Ignoring Internal Resistance: Calculating the total required resistance for a voltmeter multiplier but forgetting to subtract the meter's existing internal resistance.
- Misidentifying Instrument Functions: Confusing a frequency counter (measures frequency) with a frequency standard (generates reference), or assuming a dip meter measures impedance like an antenna analyzer.
Review Steps
- Master Core Formulas: Prioritize memorizing AC voltage conversion formulas (RMS, Peak, Peak-to-Peak) and practice basic calculations.
- Conquer Power Calculations: Understand the definition of Peak-Envelope Power (PEP) and practice applying the PEP formula using dummy loads and oscilloscope readings.
- Categorize Test Instruments: Create a comparison table of main uses, measurement targets, and limitations for oscilloscopes, frequency counters, signal generators, and dip meters.
- Tackle Meter Extensions: Draw equivalent circuits for voltmeters and ammeters, using Ohm's law to derive series and parallel resistor values, emphasizing the role of internal resistance.
Quick Checks
- Given an RMS voltage, can you quickly calculate its Peak and Peak-to-Peak values?
- Can you accurately write down the formula to calculate PEP using Peak-Envelope Voltage (PEV) measured on an oscilloscope?
- When viewing a Lissajous figure on an oscilloscope, can you correctly use the ratio of horizontal to vertical loops to find an unknown frequency?
- When extending the range of a voltmeter versus an ammeter, do you use series or parallel resistors, and what must you remember during the calculation?
Questions in This Topic
Choose Practice ModeA-003-001-001What is the easiest amplitude dimension to measure by viewing a pure sine wave on an oscilloscope?A-003-001-002What is the RMS value of a 340 volt peak-to-peak pure sine wave?A-003-001-003What is the equivalent to the RMS value of an AC voltage?A-003-001-004If the peak value of a 100 Hz sinusoidal waveform is 20 volts, the RMS value is:A-003-001-005In applying Ohm's law to AC circuits, current and voltage values are:A-003-001-006The effective value of a sine wave of voltage or current is:A-003-001-007AC voltmeter scales are usually calibrated to read:A-003-001-008An AC voltmeter is calibrated to read the:A-003-001-009Which AC voltage value will produce the same amount of heat as a DC voltage, when applied to the same resistance?A-003-001-010What is the peak-to-peak voltage of a sine wave that has an RMS voltage of 120 volts?A-003-001-011A sine wave of 17 volts peak is equivalent to how many volts RMS?A-003-002-001The 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:A-003-002-002To 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?A-003-002-003Peak-Envelope Power (PEP) for SSB transmission is:A-003-002-004The formula to be used to calculate the power output of a transmitter into a resistor load using a voltmeter is:A-003-002-005How 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 (where PEP = Peak-Envelope Power, PEV = Peak-Envelope Voltage, Vp = peak-voltage, RL = load resistance)?A-003-002-006What 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?A-003-002-007What 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?A-003-002-008What is the output PEP of an unmodulated carrier transmitter if a wattmeter connected to the transmitter output indicates an average reading of 1060 watts?A-003-002-009What 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?A-003-002-010What 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?A-003-002-011An 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?A-003-003-001What is a dip meter?A-003-003-002What does a dip meter do?A-003-003-003What two ways could a dip meter be used in an amateur station?A-003-003-004A dip meter supplies the radio frequency energy which enables you to check:A-003-003-005A dip meter may not be used directly to:A-003-003-006The dial calibration on the output attenuator of a signal generator:A-003-003-007What is a signal generator?A-003-003-008A dip meter:A-003-003-009Which two instruments are needed to measure FM receiver sensitivity for a 12 dB SINAD ratio (signal + noise + distortion over noise + distortion)?A-003-003-010The dip meter is most directly applicable to:A-003-003-011Which of the following is not a factor affecting the frequency accuracy of a dip meter?A-003-004-001What does a frequency counter do?A-003-004-002What factors limit the accuracy, frequency response and stability of a frequency counter?A-003-004-003How can the accuracy of a frequency counter be improved?A-003-004-004If a frequency counter with a time base accuracy of +/- 0.1 PPM (parts per million) reads 146 520 000 Hz, what is the most that the actual frequency being measured could differ from that reading?A-003-004-005If a frequency counter, with a time base accuracy of 10 PPM (parts per million) reads 146 520 000 Hz, what is the most the actual frequency being measured could differ from that reading?A-003-004-006The clock in a frequency counter normally uses a:A-003-004-007The frequency accuracy of a frequency counter is determined by:A-003-004-008Which device relies on a stable low-frequency oscillator, with harmonic output, to facilitate the frequency calibration of receiver dial settings?A-003-004-009What is the traditional way of verifying the accuracy of a crystal calibrator?A-003-004-010Out of the following oscillators, one is NOT, by itself, considered a high-stability reference:A-003-004-011You want to calibrate your station frequency reference to the WWV signal on your receiver. The resulting beat tone must be:A-003-005-001If 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-003-005-002What factors limit the accuracy, frequency response and stability of an oscilloscope?A-003-005-003How can the frequency response of an oscilloscope be improved?A-003-005-004You can use an oscilloscope to display the input and output of a circuit at the same time by:A-003-005-005An oscilloscope cannot be used to:A-003-005-006The bandwidth of an oscilloscope is:A-003-005-007When using Lissajous figures to determine phase differences, an indication of zero or 180 degrees is represented on the screen of an oscilloscope by:A-003-005-008A 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:A-003-005-009An oscilloscope probe must be compensated:A-003-005-010What is the best instrument to use to check the signal quality of a CW or single-sideband phone transmitter?A-003-005-011What is the best signal source to connect to the vertical input of an oscilloscope for checking the quality of a transmitted signal?A-003-006-001A meter has a full-scale deflection of 40 microamperes 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:A-003-006-002A 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 full-scale deflection. It would be necessary to insert a:A-003-006-003A 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:A-003-006-004The sensitivity of an ammeter is an expression of:A-003-006-005Voltmeter sensitivity is usually expressed in ohms per volt. This means that a voltmeter with a sensitivity of 20 kilohms per volt would be a:A-003-006-006The sensitivity of a voltmeter, whose resistance is 150 000 ohms on the 150-volt range, is:A-003-006-007The range of a DC ammeter can easily be extended by:A-003-006-008What happens inside a multimeter when you switch it from a lower to a higher voltage range?A-003-006-009How can the range of an ammeter be increased?A-003-006-010Where should an RF wattmeter be connected for the most accurate readings of transmitter output power?A-003-006-011At what line impedance do most RF wattmeters usually operate?