Ham Radio General Class Test FREE Ham Radio General Class Test Electrical and RF Safety Questions and Answers 3

Question 1

What precaution should be taken before working on an antenna that uses a rotator on a tower?

Accepted Answer

Lock out the rotator control and disconnect power to the rotator

Answer

Locking out and disconnecting power to the rotator prevents accidental rotation while someone is working on or near the antenna, which could cause serious injury.

Question 2

Which frequency range generally poses the greatest RF absorption risk to the human body?

Accepted Answer

30 to 300 MHz

Answer

The human body absorbs RF energy most efficiently in the 30 to 300 MHz range because body dimensions are resonant at those frequencies, making VHF particularly concerning.

Question 3

What is the function of a bleeder resistor in a high-voltage power supply?

Accepted Answer

To discharge filter capacitors when the supply is turned off

Answer

Bleeder resistors safely discharge high-voltage filter capacitors after the power supply is turned off, preventing lethal shocks from stored energy.

Question 4

When performing an RF safety evaluation, which of the following factors does NOT affect the calculated safe distance?

Accepted Answer

The color of the antenna insulation

Answer

RF exposure calculations depend on power, antenna gain, frequency, and feed line loss, but the physical color of antenna components has no effect on RF field strength.

Question 5

What is the main electrical hazard associated with a linear amplifier that uses vacuum tubes?

Accepted Answer

Potentially lethal high-voltage DC on the plate circuit

Answer

Vacuum tube linear amplifiers operate with plate voltages typically ranging from 1,500 to 4,000 volts DC, which is instantly lethal upon contact.

Ham Radio General Class Test Practice Test

Ham Radio General Class Test Practice Test

Ham Radio General Class Test FREE Ham Radio General Class Test Electrical and RF Safety Questions and Answers 3