Intermediate Licence: Building on the Foundation

| January 19, 2012

Interm_6This brand new revised and updated 6th edition of Intermediate Licence: Building on the Foundation is the latest incarnation of this invaluable book for those seeking to upgrade their Foundation callsign.

Click cover picture to buy this online.


Corrections, updates and additional information

Additional material

Important Note – Licence Conditions Changes
Following changes to the UK Licence Conditions for examinations after 1st October 2015 the following clauses will be tested on the basis of the amendments made by Ofcom.  Examinations taken before this date will be on the basis of that printed in the book.  These changes replace those printed in all previous editions.

Page 18: 2c.1
replace the entire section as far as 2c.2 (page 19) with the text below.

2c.1 Recall the requirements for station identification.

13(1)   The Licensee, or, if this Licence is a Full Licence, then any other authorised person who uses the Radio Equipment, shall ensure that:

(a) the station is clearly identifiable at all times;

(b) the Callsign is transmitted as frequently as is practicable during transmissions, unless the specific requirements of Note (g) to the Notes to Schedule 1 of this Licence apply; and

(c) the Callsign is given in voice or other appropriate format consistent with the mode of operation.

The licence requires you to make sure your transmissions can be identified to you, or your station if you are supervising someone else using your callsign. It is left to your common sense to decide how often this is. For many years this was stated to be at least every 15 minutes but amateur practice has always been to give the callsign rather more frequently but not on every short ‘over’.

Identifying during a ‘CQ’ call allows a reply to be directed to you by using your callsign and you will know who replied because they will have given their callsign. It may also be your first transmission on the frequency or mode so you need to make yourself ‘identifiable’ to comply with the Licence.

Of more interest at Intermediate is the use of other modes of transmission, Morse or one of the many data modes. Some data modes are designed to squeeze in between other signals, taking up very little bandwidth, others are designed to work ‘down in the noise’ where a person using voice might not even realise you are there. Each mode will have its own software decoder and you need to identify yourself using that mode and re-identify if you change modes. Some systems also have the option to identify in Morse as well as the mode being used. There is no requirement to do that in the UK Licence, only to identify yourself in the mode being used.

Some very weak signal modes require a long time to send a single message. This is allowed for by clause 13(1)(b) in the licence ‘as frequently as practicable’. It might not be practicable to send the callsign very often; indeed it could take 20 minutes just to send it once!

You are expected simply to use your common sense to give your callsign frequently but without so disrupting the flow of the conversation that it becomes silly.

Page 19 column 1  2c.2,
change lettering to match Licence as follows:

(u) now (t)
(x) now (w)

Page 46, col 2
2nd para headed 7(5), last line.

Replace ‘this Clause 4’ with ‘this Clause 7’

Page 47, col 2
The picture of Terms, Conditions and Limitations document is illustrative only but it is now out of date – strike through

Revisions to the 2011 edition:

Page 22 – QSL cards (8f.2)
In 3rd paragraph, replace from ‘You should note that anyone can…’ to ‘…can send cards through it.’ with ‘To use the UK Bureau you need to either be an RSGB member or have paid to receive cards but only RSGB members can send cards through it. If you would like details of how the RSGB operates the bureau please visit .

Page 67 – column 2, paragraph 2, replace from ‘FM (VHF or UHF): wavy…’ to ‘…time with engine speed.’ with the following:
“Analogue TV transmissions in the UK have ceased although there will be some analogue TVs with external ‘set top boxes’ still in use for a while. These remaining analogue sets may continue to show some signs of local interference from radio transmissions, electric motors and car iginition systems. Common effects include wavy lines, loss of colour, dotted lines, loss of sound and audio breakthrough.”

Page 70 –Interference from modulation (4e.1)
You may recall from your Foundation studies that it is important to set your microphone gain, TNC, or PC audio output, such that you keep your signals free from distortion and so you do not cause interference to other radio users. Let’s expand on that a little.

In an AM transmitter, excessive audio amplitude will cause ‘overmodulation’. This will cause the modulated signal to become distorted and can make the bandwidth of the signal wider than the usual 6kHz. That would cause interference to other stations on adjacent radio frequencies and make you very unpopular! The same applies to SSB, which is a ‘special kind of AM’ with a bandwidth that is half that of an AM signal; overmodulation will result in a signal that is wider than 3kHz and so have the potential to cause interference to adjacent channels.

In an FM transmitter, the amplitude of your audio frequency will cause the waveform to deviate more than is required; a condition known as ‘overdeviation’. This would cause your signals to be unintelligible and cause interference to other stations on adjacent radio frequencies, which is clearly undesirable and a breach of your licence conditions.

For AM, SSB and FM transmitters, having the microphone gain control, or the PC sound output, set too high can cause the microphone amplifier in the transmitter to produce AF harmonics, making the bandwidth of the audio fed to the modulator much wider than it should be.  This excessive audio bandwidth can also cause overmodulation and/or overdeviation.

These modulation methods are examined in more detail at the Advanced level. At this level it is sufficient to recall that applying excessive audio amplitude or excessive audio bandwidth to a modulator can cause excessive AM bandwidth or excessive FM deviation and that both can cause interference to adjacent radio frequencies.

Previous Corrections
Since late 2013 the RSGB has been shipping a revised 6th edition of the Intermediate Licence Book first published in 2011. No corrections to any previous editions are now listed.


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