The TARGET
HF3
receiver covers the entire spectrum from
30
kHz to
30
MHz.
For the beginner, what
does
this mean???
The symbol Hz (pronounced Hertz, and named after a famous radio
pioneer) represents one complete electromagnetic wave in a second.
A
kilohertz (kHz) is one thousand waves per second, and a Megahertz
(MHz),
a million waves in a second. The number
of
waves per second is
called the Frequency.
1
WAVE
IN
1
SECOND
=
1
HERTZ
Often a reference is made to a stations wavelength rather than it’s
frequency. High frequency signals have short wavelengths and low
frequency signals have
long
wavelengths. The frequency of a signal in
kHz is given by dividing
300,000
by the wavelength in metres.
SHORT
WAVE
MEDIUM
WAVE
-
LONG
WAVE
-
-
HIGH
FREQUENCY
LOW
FREQUENCY
Why are high frequency waves shorter than low frequency
???
Imagine that you could see a wave travelling past you at the speed of
light. The wavelength would be the distance between two adjacent
waves.
If
you increase the frequency of the waves then you would get
more waves in the same space
so
the wavelength would be shorter.
1