Antenna and Line Installation Flashcards
6 cards from real NWSA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Antenna and Line Installation flashcards as text
When installing a sector antenna on a tower, what determines the correct mounting orientation?
Answer: The RF design plan specifying azimuth and mechanical tilt requirements
The RF design plan specifies exact azimuth and tilt angles to ensure proper coverage patterns as designed by the RF engineer.
What hazard must be addressed before disconnecting an energized antenna from a transmission line?
Answer: The RF source must be de-energized and locked out/tagged out
RF energy from an energized antenna can cause serious burns and tissue damage. Lockout/tagout ensures the transmitter is off and cannot be accidentally re-energized.
What is the function of a diplexer or triplexer in an antenna system?
Answer: It combines or separates multiple frequency bands onto a single antenna or transmission line
Diplexers and triplexers combine multiple frequency bands to share a single antenna or cable run, reducing the number of antennas and cables needed on a tower.
What is the minimum requirement for documenting an antenna installation upon completion?
Answer: As-built documentation including photos, sweep test results, and GPS coordinates of installed equipment
As-built documentation creates a permanent record of what was installed, where, and its measured performance, essential for future maintenance and regulatory compliance.
Why must PIM (Passive Intermodulation) testing be performed on antenna systems?
Answer: To detect unwanted signal interference caused by loose connections or dissimilar metals
PIM testing detects intermodulation interference generated by non-linear junctions such as loose connectors or corroded contacts that create unwanted signals.
When installing jumper cables between the main transmission line and antenna ports, what critical specification must be maintained?
Answer: The jumper impedance must match the system impedance, typically 50 ohms
Impedance mismatches between jumpers and the system create signal reflections and power loss, degrading the antenna system's performance.