What is Amateur (Ham ) Radio ??. It’s a hobby, a technical hobby with a large number of different...

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Foundation Course

What is Amateur (Ham ) Radio ??

Foundation Course

What is Amateur (Ham ) Radio ??

What is amateur radioIt’s a hobby, a technical hobby with a large number of different activities within it. It contains a certain element of self-training and experimentation, it is non commercial – a hobby !!

Why become an amateur• To experiment with radio’s• To talk to people around the world and make friends• Get involved in a niche area such as RAYNET• Get a better understanding of electronics/computers• Have FUN !!!!!!!

The Foundation Licence is the UK entry level which will enable you to start transmitting on the air .

Modes: Voice, SSTV, RTTY, Data, FSTV, Morse

Modulation – SSB, FM, AM, CW, FSK, PSK

Focus Groups – satellites, moon bounce, clubs, rallies etc.

Others - RSGB, Rallies, QSO Bureau, contest,

Bands: HF, VHF, UHF, Microwaves

Reproduced from Radio Communications Foundation booklet.

The frequency allocation table for the VHF band is shown above. It indicates that we share the spectrum with other users and we must ensure that we do not interfere with their frequencies.

Radio Spectrum

VLF = Very Low Frequency LF = Low Frequency MF = Medium frequencyVHF = Very High Frequency UHF = Ultra High FrequencySHF = Super High Frequency EHF = Extra High Frequency

Reproduced from Radio Communications Foundation booklet

As the Frequency increases its wavelength shrinks

Antenna sizes are proportional to wavelength

Therefore higher frequencies have smaller antennas

A copy of conversation chart is supplied in the exam

reproduced from Wikipedia

Very low frequency or VLF refers to radio frequencies (RF) in the range of 3 khz to 30 khz and wavelengths from 10 to 100 kilometres - submarines

HF -The dominant means of long distance communication in this band is skywave(skip) propagation, in which radio waves directed at an angle into the sky reflect back to Earth from layers of ionized atoms in the ionosphere. By this method HF radio waves can travel beyond the horizon, around the curve of the Earth, and can be received at intercontinental distances. However, suitability of this portion of the spectrum for such communication varies greatly with a complex combination of factors

reproduced from Wikipedia

Very high frequency (VHF) is the ITU-designated range of radio frequency electromagnetic waves from 30 Mhz to 300 Mhz,

RSGB Publication 2013

The RSGB (Radio Society of Great Britain) acts on behalf of amateurs lobbying for frequencies. Internationally the body which tries to co-ordinate the band plan is IARU (International Amateur Radio Union)

Different terminology for band description

HF: 7MHZ = 40m 21MHZ = 15m 29MHZ = 10m

VHF: 50MHZ = 6m 145MHZ = 2m

UHF: 430MHZ = 70cms

Note – as frequencies rise wavelength decrease.

Revision Questions

HFWhat does the following stand for:

High Frequency

VHF Very High Frequency

UHFUltra High Frequency

SSB

Modulation: What is ??

Single Side Band

FMFrequency modulation

AMAmplitude modulation

CWCarrier wave

What is the frequency range of:

HF

3 to 30 mhz

VHF

30 – 300 mhz

Thurrock Training Team