Ham Tech Class - Sets 4 & 5 Flashcards
What must be considered to determine the minimum current capacity needed for a transceiver power supply?
D. All of these choices are correct (A. Efficiency of the transmitter at full power output, B. Receiver and control circuit power, C. Power supply regulation and heat dissipation) - T4A01 (D)
How might a computer be used as part of an amateur radio station?
D. All of these choices are correct (A. For logging contacts and contact information, B. For sending and/or receiving CW, C. For generating and decoding digital signals) - T4A02 (D)
Why should wiring between the power source and radio be heavy-gauge wire and kept as short as possible?
A. To avoid voltage falling below that needed for proper operation - T4A03 (A)
Which computer sound card port is connected to a transceiver’s headphone or speaker output for operating digital modes?
C. Microphone or line input - T4A04 (C)
What is the proper location for an external SWR meter?
A. In series with the feed line, between the transmitter and antenna - T4A05 (A)
Which of the following connections might be used between a voice transceiver and a computer for digital operation?
C. Receive audio, transmit audio, and push-to-talk (PTT) - T4A06 (C)
How is a computer’s sound card used when conducting digital communications?
C. The sound card provides audio to the radio’s microphone input and converts received audio to digital form - T4A07 (C)
Which of the following conductors provides the lowest impedance to RF signals?
D. Flat strap - T4A08 (D)
Which of the following could you use to cure distorted audio caused by RF current on the shield of a microphone cable?
D. Ferrite choke - T4A09 (D)
What is the source of a high-pitched whine that varies with engine speed in a mobile transceiver’s receive audio?
B. The alternator - T4A10 (B)
Where should the negative return connection of a mobile transceiver’s power cable be connected?
A. At the battery or engine block ground strap - T4A11 (A)
What may happen if a transmitter is operated with the microphone gain set too high?
B. The output signal might become distorted - T4B01 (B)
Which of the following can be used to enter the operating frequency on a modern transceiver?
A. The keypad or VFO knob - T4B02 (A)
What is the purpose of the squelch control on a transceiver?
D. To mute receiver output noise when no signal is being received - T4B03 (D)
What is a way to enable quick access to a favorite frequency on your transceiver?
B. Store the frequency in a memory channel - T4B04 (B)
Which of the following would reduce ignition interference to a receiver?
C. Turn on the noise blanker - T4B05 (C)
Which of the following controls could be used if the voice pitch of a single-sideband signal seems too high or low?
D. The receiver RIT or clarifier - T4B06 (D)
What does the term “RIT” mean?
B. Receiver Incremental Tuning - T4B07 (B)
What is the advantage of having multiple receive bandwidth choices on a multimode transceiver?
B. Permits noise or interference reduction by selecting a bandwidth matching the mode - T4B08 (B)
Which of the following is an appropriate receive filter bandwidth for minimizing noise and interference for SSB reception?
C. 2400 Hz - T4B09 (C)
Which of the following is an appropriate receive filter bandwidth for minimizing noise and interference for CW reception?
A. 500 Hz - T4B10 (A)
What is the function of automatic gain control, or AGC?
A. To keep received audio relatively constant - T4B11 (A)
Which of the following could be used to remove power line noise or ignition noise?
B. Noise blanker - T4B12 (B)
Which of the following is a use for the scanning function of an FM transceiver?
C. To scan through a range of frequencies to check for activity - T4B13 (C)
Electrical current is measured in which of the following units?
D. Amperes - T5A01 (D)
Electrical power is measured in which of the following units?
B. Watts - T5A02 (B)
What is the name for the flow of electrons in an electric circuit?
D. Current - T5A03 (D)
What is the name for a current that flows only in one direction?
B. Direct current - T5A04 (B)
What is the electrical term for the electromotive force (EMF) that causes electron flow?
A. Voltage - T5A05 (A)
How much voltage does a mobile transceiver typically require?
A. About 12 volts - T5A06 (A)
Which of the following is a good electrical conductor?
C. Copper - T5A07 (C)
Which of the following is a good electrical insulator?
B. Glass - T5A08 (B)
What is the name for a current that reverses direction on a regular basis?
A. Alternating current - T5A09 (A)
Which term describes the rate at which electrical energy is used?
C. Power - T5A10 (C)
What is the unit of electromotive force?
A. The volt - T5A11 (A)
What describes the number of times per second that an alternating current makes a complete cycle?
D. Frequency - T5A12 (D)
In which type of circuit is current the same through all components?
A. Series - T5A13 (A)
In which type of circuit is voltage the same across all components?
B. Parallel - T5A14 (B)
How many milliamperes is 1.5 amperes?
C. 1500 milliamperes - T5B01 (C)
What is another way to specify a radio signal frequency of 1,500,000 hertz?
A. 1500 kHz - T5B02 (A)
How many volts are equal to one kilovolt?
C. One thousand volts - T5B03 (C)
How many volts are equal to one microvolt?
A. One one-millionth of a volt - T5B04 (A)
Which of the following is equal to 500 milliwatts?
B. 0.5 watts - T5B05 (B)
If an ammeter calibrated in amperes is used to measure a 3000-milliampere current, what reading would it show?
C. 3 amperes - T5B06 (C)
If a frequency display calibrated in megahertz shows a reading of 3.525 MHz, what would it show if it were calibrated in kilohertz?
C. 3525 kHz - T5B07 (C)
How many microfarads are equal to 1,000,000 picofarads?
B. 1 microfarad - T5B08 (B)
What is the approximate amount of change, measured in decibels (dB), of a power increase from 5 watts to 10 watts?
B. 3 dB - T5B09 (B)
What is the approximate amount of change, measured in decibels (dB), of a power decrease from 12 watts to 3 watts?
C. -6 dB - T5B10 (C)
What is the amount of change, measured in decibels (dB), of a power increase from 20 watts to 200 watts?
A. 10 dB - T5B11 (A)
Which of the following frequencies is equal to 28,400 kHz?
A. 28.400 MHz - T5B12 (A)
If a frequency display shows a reading of 2425 MHz, what frequency is that in GHz?
C. 2.425 GHz - T5B13 (C)
What is the ability to store energy in an electric field called?
D. Capacitance - T5C01 (D)
What is the basic unit of capacitance?
A. The farad - T5C02 (A)
What is the ability to store energy in a magnetic field called?
D. Inductance - T5C03 (D)
What is the basic unit of inductance?
C. The henry - T5C04 (C)
What is the unit of frequency?
A. Hertz - T5C05 (A)
What does the abbreviation “RF” refer to?
A. Radio frequency signals of all types - T5C06 (A)
A radio wave is made up of what type of energy?
B. Electromagnetic - T5C07 (B)
What is the formula used to calculate electrical power in a DC circuit?
A. Power (P) equals voltage (E) multiplied by current (I) - T5C08 (A)
How much power is being used in a circuit when the applied voltage is 13.8 volts DC and the current is 10 amperes?
A. 138 watts - T5C09 (A)
How much power is being used in a circuit when the applied voltage is 12 volts DC and the current is 2.5 amperes?
B. 30 watts - T5C10 (B)
How many amperes are flowing in a circuit when the applied voltage is 12 volts DC and the load is 120 watts?
B. 10 amperes - T5C11 (B)
What is impedance?
A. A measure of the opposition to AC current flow in a circuit - T5C12 (A)
What is a unit of impedance?
D. Ohms - T5C13 (D)
What is the proper abbreviation for megahertz?
D. MHz - T5C14 (D)
What formula is used to calculate current in a circuit?
B. Current (I) equals voltage (E) divided by resistance (R) - T5D01 (B)
What formula is used to calculate voltage in a circuit?
A. Voltage (E) equals current (I) multiplied by resistance (R) - T5D02 (A)
What formula is used to calculate resistance in a circuit?
B. Resistance (R) equals voltage (E) divided by current (I) - T5D03 (B)
What is the resistance of a circuit in which a current of 3 amperes flows through a resistor connected to 90 volts?
B. 30 ohms - T5D04 (B)
What is the resistance in a circuit for which the applied voltage is 12 volts and the current flow is 1.5 amperes?
C. 8 ohms - T5D05 (C)
What is the resistance of a circuit that draws 4 amperes from a 12-volt source?
A. 3 ohms - T5D06 (A)
What is the current in a circuit with an applied voltage of 120 volts and a resistance of 80 ohms?
D. 1.5 amperes - T5D07 (D)
What is the current through a 100-ohm resistor connected across 200 volts?
C. 2 amperes - T5D08 (C)
What is the current through a 24-ohm resistor connected across 240 volts?
C. 10 amperes - T5D09 (C)
What is the voltage across a 2-ohm resistor if a current of 0.5 amperes flows through it?
A. 1 volt - T5D10 (A)
What is the voltage across a 10-ohm resistor if a current of 1 ampere flows through it?
B. 10 volts - T5D11 (B)
What is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it?
D. 20 volts - T5D12 (D)
What happens to current at the junction of two components in series?
B. It is unchanged - T5D13 (B)
What happens to current at the junction of two components in parallel?
A. It divides between them dependent on the value of the components - T5D14 (A)
What is the voltage across each of two components in series with a voltage source?
C. It is determined by the type and value of the components - T5D15 (C)
What is the voltage across each of two components in parallel with a voltage source?
D. The same voltage as the source - T5D16 (D)