T3A-2014: Radio wave characteristics: how a radio signal travels; fading; multipath; wavelength vs. penetration; antenna orientation
What should you do if another operator reports that your station’s 2 meter signals were strong just a moment ago, but now they are weak or distorted?
Try moving a few feet or changing the direction of your antenna if possible, as reflections may be causing multi-path distortion
Change the batteries in your radio to a different type
Turn on the CTCSS tone
Ask the other operator to adjust his squelch control
Why are UHF signals often more effective from inside buildings than VHF signals?
The shorter wavelength allows them to more easily penetrate the structure of buildings
VHF signals lose power faster over distance
This is incorrect; VHF works better than UHF inside buildings
UHF antennas are more efficient than VHF antennas
What antenna polarization is normally used for long-distance weak-signal CW and SSB contacts using the VHF and UHF bands?
What can happen if the antennas at opposite ends of a VHF or UHF line of sight radio link are not using the same polarization?
Signals could be significantly weaker
The modulation sidebands might become inverted
Signals have an echo effect on voices
Nothing significant will happen
When using a directional antenna, how might your station be able to access a distant repeater if buildings or obstructions are blocking the direct line of sight path?
Try to find a path that reflects signals to the repeater
Change from vertical to horizontal polarization
Try the long path
Increase the antenna SWR
What term is commonly used to describe the rapid fluttering sound sometimes heard from mobile stations that are moving while transmitting?
What type of wave carries radio signals between transmitting and receiving stations?
Which of the following is a likely cause of irregular fading of signals received by ionospheric reflection?
Random combining of signals arriving via different paths
Frequency shift due to Faraday rotation
Interference from thunderstorms
Which of the following results from the fact that skip signals refracted from the ionosphere are elliptically polarized?
Either vertically or horizontally polarized antennas may be used for transmission or reception
Digital modes are unusable
FM voice is unusable
Both the transmitting and receiving antennas must be of the same polarization
What may occur if data signals propagate over multiple paths?
Error rates are likely to increase
Transmission rates can be increased by a factor equal to the number of separate paths observed
Transmission rates must be decreased by a factor equal to the number of separate paths observed
No significant changes will occur if the signals are transmitting using FM
Which part of the atmosphere enables the propagation of radio signals around the world?
● = Unseen
● = Weak
● = Review
● = Learned
● = Incorrect answer