ARRL Technician Practice Exam

What is one way to limit the risk of exceeding RF exposure limits?

1. Using no more than one antenna

2. Calculating duty cycles prior to operation

3. Increasing the distance from transmission lines

4. Decreasing the height of antennas

The correct answer is: Calculating duty cycles prior to operation

Calculating duty cycles prior to operation is an effective way to limit the risk of exceeding RF exposure limits. The duty cycle is the fraction of time that a system transmits versus the time it is in standby or inactive mode. By understanding and calculating the duty cycle of a transmitter, operators can better estimate the average power output and ensure that their operating practices stay within safe exposure limits. This careful management of transmission time helps mitigate the risks associated with prolonged exposure to RF energy. In contrast, while the other options may seem relevant, they do not directly address the need to monitor and manage RF exposure in the same proactive manner as duty cycle calculations. For instance, using multiple antennas or altering their height might impact coverage and signal strength but doesn't inherently control exposure risks attributed to transmission patterns. Increasing distance from transmission lines can provide a measure of safety but does not address the operational parameters of the transmitter itself. Therefore, calculating duty cycles is foundational for staying compliant with regulatory standards regarding RF exposure.