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Communication

4.13 Technical topics (BEG 3)

This section covers technical matters regarding frequency, wavelength and
wave types.

This may seem a bit dry and perhaps redundant to many, but it is nevertheless

something you should have some knowledge of.

4.13.1 Frequency and wavelength

Frequency refers to the frequency of something that occurs regularly.

In connection with radio engineering and electronics, the frequency is:

the number of oscillations per second.

So, what is oscillation?

Here you can see an oscillation. It has a

positive and a negative half-period.

If you have 1 oscillation per second, you say

that the frequency is 1 Hz.

Such oscillations propagate as waves in water at a speed of 300,000 km per

second.

The wavelength is referred to as the distance from wave crest to wave crest.
However, it could just as well be the distance from the beginning of a positive

half-wave to the beginning of the next positive half-wave.

If you look at the figure above, the wavelength is 300,000 km.

Now we will try a new frequency.

If you count, you will find that we have

8 oscillations here.

Flight Theory PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 429