The Basic lessons · Feedlines and antenna systems · B-006-004

Keeping Your Signal Strong: Feedline Loss and Length

Learn why longer cables and higher frequencies weaken your radio signal before it reaches the antenna. Discover how choosing the right cable type and keeping the run short preserves your power.

This lesson is part of SignalPrep Pro. The subsection's 10 exam questions are free to practise: practise B-006-004.

What this subsection asks

• What is the major adverse consequence of using RG-58 coaxial cable for a transmission line operating on the 70 cm band?
• What is the major advantage of open-wire transmission line?
• If your transmitter and antenna are 15 metres apart, but are connected by 60 metres of RG-58 coaxial cable, what should be done to reduce transmission line loss?
• As the length of a transmission line is changed, what happens to signal loss?
• As the frequency of a signal is changed, what happens to signal loss in a transmission line?
• Assuming the same transmitter and RF output power are used, what is the effect of changing the transmission line from RG- 213 coaxial cable to RG-58?
• The lowest loss transmission line on HF is:
• In what values are RF transmission line losses expressed?
• If the length of a coaxial transmission line is increased from 20 metres to 40 metres, how would this affect the line loss?
• If the operating frequency is increased, how does the transmission line loss change?