ptt over cellular mast

Radio Electromagnetic Spectrum

Radio electromagnetic spectrum refers to the range of frequencies of electromagnetic radiation that can be used for radio communication.

The spectrum is divided into several bands, each with different characteristics and uses.

Some examples of bands in the radio electromagnetic spectrum include:

Very Low Frequency (VLF): 3-30 kHz, used for communication with submarines

Low Frequency (LF): 30-300 kHz, used for navigation

Medium Frequency (MF): 300-3000 kHz, used for AM radio broadcasting

High Frequency (HF): 3-30 MHz, used for shortwave radio broadcasting and amateur radio

Very High Frequency (VHF): 30-300 MHz, used for television broadcasting, FM radio, and mobile communication.

Ultra High Frequency (UHF): 300-3000 MHz, used for television broadcasting, mobile communication, and satellite communication.

Super High Frequency (SHF): 3-30 GHz, used for microwave communication and radar.

It’s important to note that the use of frequency bands of the radio spectrum is regulated by governments and international organizations, such as the International Telecommunications Union (ITU), to avoid interference and optimise the use of these resources.

What does UHF stand for?

UHF in radio communications  stands for ‘Ultra High Frequency’

The UHF frequency band covers the range between 300 – 3000 Mhz (Mega Hertz).

UHF in radio communications is particularly useful in built up area such as cities, as the ‘wavelength’ is shorter the higher up  in frequency you go. This means that the shorter wavelength (compared to VHF) allows the signal to theoretically  go round  and through objects better.

Another advantage is that the aerials are shorter than with vhf equipment (remember higher frequency = shorter wavelength = shorter aerial). This is particularly useful for discreet and covert police operations. Shop security radios are also normally UHF.

A theoretical disadvantage of UHF compared to VHF is a shorter transmission range, though there are lots of factors involved in deciding which system will work best, and UHF systems  can be made to go long distances (worldwide in fact) by using it  in combination with the latest  internet combined technologies.