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Flashcards in Radio Wave Characteristics - T3A Deck (11):
1

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, as random reflections may be causing multi-path distortion

2

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

3

What antenna polarization is normally used for long-distance weak-signal CW and SSB contacts using the VHF and UHF bands?

Horizontal

4

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

5

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

6

What term is commonly used to describe the rapid fluttering sound sometimes heard from mobile stations that are moving while transmitting?

Picket fencing

7

What type of wave carries radio signals between transmitting and receiving stations?

Electromagnetic

8

What is the cause of irregular fading of signals from distant stations during times of generally good reception?

Random combining of signals arriving via different path lengths

9

Which of the following is a common effect of "skip" reflections between the Earth and the ionosphere?

The polarization of the original signal is randomized

10

What may occur if VHF or UHF data signals propagate over multiple paths?

Error rates are likely to increase

11

Which part of the atmosphere enables the propagation of radio signals around the world?

The ionosphere