Which of the following is a safety hazard of a 12-volt storage battery that lacks internal protection circuitry?

1. A Touching both terminals with your hands can cause electrical shock
2. B Shorting the terminals can cause burns, fire, or an explosion
3. C RF emissions from a nearby transmitter can cause the electrolyte to emit poison gas
4. D All these choices are correct

What health hazard is posed by electrical current flowing through the body?

1. A It may cause injury by heating body tissue
2. B It may disrupt the electrical functions of cells
3. C It may cause involuntary muscle contractions
4. D All these choices are correct

In the United States, what circuit does black wire insulation indicate in a three-wire 120 V AC cable?

1. A Neutral
2. B Hot
3. C Equipment ground
4. D Negative

What is the purpose of a fuse in an electrical circuit?

1. A To prevent power supply ripple from damaging a component
2. B To remove power in case of an overload
3. C To limit current and prevent shocks
4. D All these choices are correct

Why should a 5-ampere fuse never be replaced with a 20-ampere fuse?

1. A The larger fuse would be likely to blow because it is rated for higher current
2. B The power supply ripple would greatly increase
3. C Excessive current could cause a fire
4. D Voltage drop in the higher current fuse could result in excessively low voltage to the device

What is a good way to guard against electrical shock at your station?

1. A Use three-wire cords and plugs for all AC powered equipment
2. B Connect all AC powered station equipment to a common safety ground
3. C Ensure all capacitors used for high-voltage DC are fully discharged before working inside equipment
4. D All these choices are correct

Where should a lightning arrester be installed in a coaxial feed line?

1. A At the output connector of a transceiver
2. B At the antenna feed point
3. C At the AC power service panel
4. D On a grounded panel near where feed lines enter the building

Where should a fuse or circuit breaker be installed in a 120V AC power circuit?

1. A In series with the hot conductor only
2. B In series with the hot and neutral conductors
3. C In parallel with the hot conductor only
4. D In parallel with the hot and neutral conductors

What should be done to all external ground rods or earth connections?

1. A Waterproof them with silicone caulk or electrical tape
2. B Keep them as far apart as possible
3. C Bond them together with heavy wire or conductive strap
4. D Tune them for resonance on the lowest frequency of operation

What hazard exists when rapidly charging or discharging an unprotected battery?

1. A Overheating or out-gassing
2. B Excess output ripple
3. C Electric shock
4. D Overvoltage

What hazard exists in a power supply immediately after turning it off?

1. A Circulating currents in the dc filter
2. B Leakage flux in the power transformer
3. C Voltage transients from kickback diodes
4. D Charge stored in filter capacitors

Which of the following precautions should be taken when measuring high voltages with a voltmeter?

1. A Ensure that the voltmeter has very low impedance
2. B Ensure that the voltmeter and its leads are rated for use at the voltages being measured
3. C Ensure that the circuit is grounded through the voltmeter
4. D Ensure that the voltmeter is set to the correct frequency