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The Syllabus. Issue no.2  Dec 2004

The term "recall" indicates a need to recall a basic fact and apply it fairly directly to a situation or question; extensive background knowledge and understanding is not expected although, at the advanced level some degree of interpretation may be required.

The term "understand" indicates the need for a wider understanding of the origin and implications of the subject area. Questions will assume such understanding.

Examination Questions.

Examination questions will assume a knowledge and understanding of the basic principles from all parts of the Foundation, Intermediate and Advance syllabuses, although the question itself will be clearly aimed at the relevant syllabus item.

For example, in tackling a question on interference, the candidate may need to demonstrate an appreciation of how unwanted frequencies are produced, their potential to cause interference, how they might enter an affected device and how this might be identified and avoided. This might require knowledge of harmonics, mixing and the susceptible frequencies of the victim device.

It will be assumed that the candidate has some familiarity with amateur operating practices and procedures as outlined in all 3 syllabuses. This will include, for example, a broad understanding of such issues as amateur band plans although examination of specific knowledge will be in line with the syllabus.

Some time spent on-air either as a listener or as an amateur operator at Foundation or Intermediate level will be advantageous in understanding the purpose and context of syllabus items and examination questions.


A formula sheet will be provided during the examination. The formula will not be titled or explained and candidates will be expected to recognise which formula is appropriate and may need to transpose it depending on the parameters to be calculated.


Nature of Amateur Radio

1a.1 Nothing examinable at this level.

Question 1

Licensing Conditions

Note: that a full copy of the leaflet BR68 will be provided in the exam

Also, pending reprinting of documents, the titles Radiocommunications Agency and Ofcom will be regarded as synonymous and references to the Secretary of State should be interpreteted as references to Ofcom.

Licence document Understand the clauses in BR68 set out below:

This includes the Notes to the Booklet BR68 where cited in the licence clauses or where they provide additional information.

2a Types of licence and format of call signs and location


Identify the types of UK licence and the format of all call signs in use including regional secondary locators, but NOT including club, special event and contest call signs.

12(2) Licence documents

1(10), 1(11)(a)(b)(c), 1(12), 12(1)(g)    Notes (a)(i)(j)

Location 7(3), 7(4),7(5) Notes (v)(w) Identity of Location

Question 2

2b User Services and International disaster


1(2), 1(2A), 12(1)(o) User Services

1(3) International disaster communications and frequencies used.

Messages may be passed, internationally, on behalf of non-licensed persons;

Non-amateur station involved in international disaster communications may also be heard on amateur frequencies.

Question 3

2c Supervision of licensed and non-licensed persons.


1(8) Meaning of 'direct supervision', duties of the supervisor and nature of greetings messages.

1(8A) Meaning of a recognised training course as defined in note 'fa' to BR68. Identification of persons qualifying.

2(8)(b) Meaning of 'direct supervision' and identity of persons who may operate.

2(9) Identification of a disqualified person.

2(10) Use and supervision of Club Stations.

7(2) Identification while under supervision.

12(1)(e) Meaning of Authorised Club member.

Recall that Foundation and Intermediate licensees are not permitted by their licenses to supervise the operation of an amateur radio station.

Question 4

2d Maritime mobile operation.


1(11)(d) Location of station, including Maritime Mobile.

2(12) Installation and radio silence.

2(13) Know the 3 ITU regions and that the frequencies are given in the ITU Radio Regulations.

7(4) Suffix '/MM' to call sign.

8(3) Close down

12(1)(d) Meaning of "At Sea".

12(1)(l) Meaning of "Tidal Water".

Question 5

2e CEPT Recommendation and reciprocal licensing.

2e.1 Operation in the UK by CEPT visitors

10, 10(1), 10(2), 10(3), 10(5)

2e.2 Operation abroad under the CEPT Recommendations and under reciprocal licences.

11 Operation in CEPT countries by UK licenced amateurs

11(1) Rules for operation in CEPT countries.

11(2) Temporary licences not valid for CEPT operation.

Recall that many countries will offer reciprocal licenses to UK amateurs with a Full licence and that operation is in accordance with the host country's rules.

the word Full used in this section means the licence issued after a successful Advanced examination

Question 6

2f.1 Messages

1(4), 1(6), 1(7) 1(9) Messages

2(2) Receipt of messages from amateurs on non-UK frequencies

3(3), pecuniary interest and permitted advertising

5(1), 5(2), 5(3), 5(4) recorded and re-transmitted messages.

Notes (c) (d) (e) (h) inappropriate messages

Question 7

2g Unattended operation

2g.1 Clauses 2(3) NOT including NGR's, 2(4), 2(5), 2(6)

Question 8

2h Logging and Identification

2h.1 6(1), 6(2), 6(3), 6(4), 6(5) Notes (q)(r)(s) Logs

7(1), 7(1A), 7(6); Notes (s)(t)(u)(v)(w) Identification   {using new lettering as per NoV}

Question 9

2i Apparatus, Inspection Closedown and renewal

2i.1   4(1), 4(2), 4(3), 4(4), 4(5) Notes (k)(l)(m)(n)(o) Apparatus

8(1),8(2),8(4) Notes (l) (m) Inspection and closedown

9(1), 9(2), 9(3), 9(4) Note (a) Renewal

Question 10

2j Schedule

2j.1 Clause 2(1) and apply the Schedule to the licence including the notes to the schedule.

Technical Aspects

Note that any unit prefix from pico to Giga may be used (in multiples of 103) in any question or calculation.

Question 11

3a Potential Difference and Electromotive Force

3a.1 Understand the difference between potential difference (p.d.) and electromotive force (e.m.f.).

Understand the concept of source resistance (impedance) and voltage drop due to current flow.

3b Resistance

3b.1 Understand and apply the formulae for calculating the combined values of resistors in series and/or in parallel.

Resistors of different values of may be used in series, parallel or combined series and parallel circuits.

3c  Power in DC circuits

3c.1 Understand and apply the formula relating power to potential difference, current and resistance.

3d Potential dividers

3d.1 Understand that two or more resistors can be arranged to act as a potential divider and apply the formula.

Question 12

3e Capacitance

3e.1 Understand the factors influencing the capacitance of a capacitor; area and separation of the plates, permittivity of dielectrics and formula C=KA/d.

3e.2 Understand that capacitors have a breakdown voltage and that they need to be used within that voltage.

3e.3 Recall that different dielectrics are used for different purposes, e.g. air, ceramic, mica and polyester; and that with some dielectrics, losses increase with increasing frequency.

3e.4 Understand the charging and discharging of a capacitor in a CR circuit and the meaning of the time constant T=CR.

Recall the dangers of stored charges on large or high voltage capacitors.

Recall that large value resistors can be used to provide leakage paths for these stored charges.

3e.5 Recall and apply the formulae for calculating the combined values of capacitors in series and in parallel

Question 13

3f Inductance

3f.1 Understand the term 'self inductance' and recall that a 'back e.m.f.' is produced as current flow changes in an inductor.

3f.2 Recall that the inductance of a coil increases with increasing number of turns, increasing coil diameter and decreasing spacing between turns.

Understand the use of high permeability cores and slug tuning.

3f.3 Understand the rise and fall of current in an LR circuit.

3f.4 Understand and apply the formulae for calculating the combined values of inductors in series and in parallel.

Question 14

3g AC circuits

3g.1 Understand that the root mean square (r.m.s.) value of a sine wave has the same heating effect as a direct current of the same value and that it is equal to 0.707 of its peak value.

3g.2 Recall that the period of a sine wave is equal to 1/f and that the frequency of a sine wave is equal to 1/T (where f = frequency in Hertz and T = time in seconds).

3g.3 Understand the concept of phase difference, that it is expressed in degrees and that a full cycle is equal to 360 degrees.

Question 15

3h.1 Recall that for a resistor, the p.d. and current are in phase

Recall that current lags potential difference by 90°in an inductor and that current leads by 90° in a capacitor.

Recall that the term 'reactance' describes the opposition to current flow in a purely inductive or capacitive circuit where the phase difference between V and I is 90°.

Understand and apply the equations for inductive and capacitive reactance.

3h.2 Understand that impedance is a combination of resistance and reactance and apply the formula for impedance and current in a series CR or LR circuit.

3h.3 Understand the use of capacitors for coupling (d.c. blocking) and decoupling a.c. signals (including r.f. bypass) to ground.

Question 16

3i Tuned Circuits

3i.1 Understand that at resonance XC = XL and the formula for resonant frequency

Apply the formula to find values of f,L or C from given data.

3i.2 Identify resonance curves for series and parallel tuned circuits.

3i.3 Understand the concept of the magnification factor Q as applied to the voltages and currents in a resonant circuit.

Understand and and apply the formula for magnification factor Q as applied to the voltages and currents in a resonant circuit.

Recall the definitions of the half power point and the shape factor of resonance curves

Understand and apply the equation for Q given the resonant frequency and the half power points on the resonance curve.

3i.4 Understand the meaning of dynamic resistance.

Understand and apply the formula for RD given component values.

Understand the effect of damping resistors in a tuned circuit.

3i.5 Recall the equivalent circuit of a crystal and that it exhibits series and parallel resonance.

3i.6 Recall that voltages and circulating currents in tuned circuits can be very high and understand the implications for component rating.

Question 17

3j Transformers

3j.1 Understand the concept of mutual inductance.

Understand and apply the formula relating transformer primary and secondary turns to primary and secondary potential differences and currents.

3j.2 Understand and apply the formula relating transformer primary and secondary turns to primary and secondary impedances.

3j.3 Understand the cause and effects of eddy currents and the need for laminations (or ferrites) in transformers.

Question 18

3k Filters

3k.1 Identify the circuits of low pass, high pass, band pass and band stop (notch) filters and their response curves. Understand the concept of the cut-off frequency.

Recall that crystals can be used in filter circuits.

Question 19

3l Screening

3l.1 Recall that screening with thin metal sheet is effective in reducing unwanted radiation from equipment and/or between stages within equipment.

3m Temperature effects

3m.1 Recall that temperature has an effect on the value of components; those with negative coefficients will reduce in value as temperature rises whereas those with positive coefficients will increase in value. Understand the effect this will have on tuned circuits and remedial measures.

3o  Decibels

3o.1 Understand the equations for decibel power and voltage ratios.

Recall (or determine) the power gain or loss of various dB ratios based on ( 3, 6, 9, 12, 15 and 10, 20, 30dB. (This includes examples such as 25W 20-6=14dBW.)

Question 20

3n Solid state devices

3n.1 Understand that doping of semiconductor material (silicon and germanium) produces p-type (electron deficient) and n-type (electron rich) semiconductors. Understand current flow in terms of electron and hole movement.

Understand how the p-n junction forms a semiconductor diode.

Understand the formation and effect of the depletion layer.

Understand that an applied potential difference can cause electrons to flow across the pn junction (forward bias) or prevent electron flow (reverse bias) depending on polarity.

3n.2 Recall that a Zener diode will conduct when the reverse bias potential is above its designed value and identify its V/I characteristic curve.

3n.3 Understand that the depletion layer in a reverse biased diode forms the dielectric of a capacitor and that the magnitude of the reverse bias affects the width of the layer and the capacitance.

3n.4 Understand the 3 layer model of the transistor (npn and pnp) and the channel model of the FET.

Question 21

3n.5 Understand the basics of biasing bipolar and FET transistors (including dual gate devices).

3n.6 Identify different types of small signal amplifiers (e.g. common emitter (source), emitter follower and common base) and explain their operation in terms of input and output impedances, current gain, voltage gain and phase change.

3n.7 Recall the characteristics and typical circuit diagrams of different classes of amplifiers (i.e. A, B, A/B and C).

3n.8 Understand the concept of the efficiency of an amplifier stage and be able to estimate expected r.f. output power for a given d.c. input power, given the stage's efficiency.

Question 22

3p Mains Power Supplies

3p.1 Recall the circuit diagrams and characteristics of different types of rectifier and smoothing circuits (i.e. half wave, full wave and bridge).

3p.2 Understand the need for rectifier diodes to have a sufficient peak inverse voltage (PIV) rating and be able to calculate the PIV in diode/capacitor circuits.

3p.3 Understand the function of stabilising circuits and identify different types of stabilising circuits (i.e. Zener diode/pass transistor and IC)

Note: questions on the characteristics of individual components are covered earlier in this syllabus, e.g. 3n.2. This sub-section is on complete circuits.

Question 23

4a Transmitters and Receivers

4a.1 Understand the block diagram of an s.s.b transmitter employing mixers to generate the final frequency.

Understand the block diagram of an f.m. transmitter employing either frequency multipliers or mixers to generate the final frequency.

4b Oscillators

4b.1 Understand the function of the components in typical VFO and crystal oscillators.

4c Frequency synthesis

4c.1 Recall the block diagram of a frequency synthesiser and the functions of the stages (i.e. oscillator, fixed divider, phase detector, LPF, voltage controlled oscillator and programmable divider).

Recall how sine waves may be produced by direct digital synthesis and the block diagram of a simple synthesiser. Recall that increasing the number of bits in the synthesiser will increase the purity of the signal.

Question 24

4d Frequency multipliers

4d.1 Understand that frequency multipliers use harmonics to generate frequencies above an oscillator's fundamental frequency (e.g. in a microwave transmitter)

4e Mixers

4e.1 Understand that the desired frequency is often produced by mixing together the output from two or more frequency sources, e.g. v.f.o., crystal oscillator or synthesiser.

Understand how unwanted frequencies may also be produced.

Question 25

4f Modulation

4f.1 Recall the meaning of the term peak deviation.

Recall the meanings of narrow band and wide band modulation for frequency modulation

Recall the meaning of depth of modulation for amplitude modulation

4f.2 Understand the operation of a.m., s.s.b, and f.m. modulators.

Recall the bandwidth of such transmissions.

4f.3 Understand, in functional terms, the operation of data modulators for F1B (direct frequency shift), F2B (frequency shift keyed audio tone on an f.m. transmitter) and J2B (frequency shift keyed audio tone on an s.s.b. transmitter).

Question 26

4g Power Amplifiers

4g.1 Understand the need for linear amplification and identify which forms of modulation require a linear amplifier.

4g.2 Recall the function of the main components; anode/collector load, bias, input circuit, output filter and matching in a PA circuit.

4g.3 Recall the operation of a valve in a power amplifier. Recall the function for the heater, cathode, control grid and anode.

Recall the advantages and disadvantages of valve PA circuits.

4g.4 Understand the implications for PA rating of different types of modulation and the effects of speech processing, with particular regard to peak to average power ratios.

4g.5 Recall the function of automatic level control within the power amplifier and when using an external power amplifier. Recall the function and use of a manual r.f. power control.

Question 27

4h Transmitter Interference

4h.1 Recall the effect and the importance of minimizing drift.

4h.2 Recall the cause and effect of 'chirp' and identify suitable remedies.

Recall the cause and effect of 'key clicks' and the shaping of Morse keying waveforms.

Question 28

4h.3 Understand ways to avoid generating harmonics (e.g. use of push-pull amplifiers, use of inductive coupling between stages, avoiding high drive levels).

Recall that transmitters may radiate unwanted mixer products and identify suitable remedies

Understand the use of low and band pass filters in minimizing the radiation of unwanted harmonics and mixer products.

4h.4 Recall that unwanted emissions may be caused by parasitic oscillation and/or self oscillation and identify suitable remedies

4h.5 Understand that over modulation causes harmonics (of the modulating signal) which may result in excessive bandwidth.

Question 29

4h.6 Understand how frequency synthesizers may not produce the intended frequency. Identify remedial measures (out of lock inhibit).

4i External Power Amplifiers

4i.1 Understand the need to drive external power amplifiers with the minimum power required for full output and how overdriving may cause harmonics and/or spurious intermodulation products.

Question 30

4j Receiver parameters and terminology

4j.1 Understand the term selectivity and 60 dB bandwidth

4j.2 Recall that the dynamic range of a receiver is the difference between the minimum discernible signal and the maximum signal without overload. Recall the dynamic range is expressed in decibels.

4j.3 Recall, in simple terms, the meaning of "signal to noise ratio" as applied to a receiver specification. Recall that the noise generated in the receiver will influence the minimum discernible signal.

Question 31

4k Receiver architecture

4k.1 Understand the block diagram of superhet and double superhet receivers and the functions of each block.

Question 32

4l RF. Amplifier and pre-amplifier

4l.1 Recall the operation of the r.f. amplifier.

Understand that external r.f. preamplifiers do not always improve overall performance and will reduce dynamic range by an amount equal to the gain of the pre-amp. Understand that overloading will cause intermodulation and spurious signals.

4n.2 Understand the operation of an i.f. amplifier and the i.f. transformer.

Understand the concept of two LC tuned circuits utilising transformer coupling. Identify critical and over-coupled response curves.

Understand how the gain of an i.f. amplifier can be varied, how this may cause distortion and how the effects of the distortion are avoided.  Note: the reason to vary the gain (a.g.c.) is covered at item 4p.

Question 33

4m Mixer and Local Oscillator

4m.1 Understand the function of a mixer, the generation of intermediate frequencies (i.f.) and other mixer products.

Understand that for given r.f. and i.f. frequencies, there is a choice of two local oscillator (l.o.) frequency. Understand the reasons for the choice and calculate the frequencies.

4m.2 Understand the origin of the second channel or image frequency and calculate the frequency from given parameters.

4n IF amplifier

4n.1 Understand the advantages and disadvantages of high and low intermediate frequencies and the rationale for the double superhet.

Question 34

4o Demodulation

4o.1 Understand the operation of a.m., c.w., s.s.b. and f.m. demodulators.

4p Automatic Gain control

4p.1 Understand the derivation and use of an a.g.c. voltage.

Recall that automatic gain control circuits can also be used to drive S meters

Question 35

4q Down-converters and transverters

4q.1 Understand that VHF and UHF operation can be carried out by using down converters and transverters ahead of HF equipment

4r Transceivers

4r.1 Understand that transceivers normally share oscillators between the transmitter and receiver circuits; and may use common i.f. filters to limit both the transmitter and receiver bandwidths. They also use common change-over circuits.

Recall the function of the RIT control.

Question 36

Feeder and Antenna

5a Feeder basics

5a.1 Understand that the velocity factor of a feeder is the ratio of the velocity of radio waves in the feeder to that in free space and that the velocity factor is always less than unity. Be able to calculate physical feeder lengths given the frequency and velocity factor. Recall that the velocity factor for coaxial feeder with a polythene dielectric is approximately 0·67 or 2/3. Recall that feeder loss increases with increasing frequency and that lower loss feeders may be required at VHF ,UHF and above

5a.2 Understand that a quarter-wave length of feeder can be used as an impedance transformer. Apply simple examples of the formula Z02=ZinxZout.

5a.3 Recall the basic construction and use of waveguides.

5b Baluns

5b.1 Recall the construction and use of typical baluns; transformer, sleeve and choke.

Identify the circuits of 1:1 and 4:1 transformer baluns.

Question 37

5c Antennas

5c.1 Understand the equation for calculating half-wavelengths and be able to apply 'end factor correction' in calculating the approximate physical lengths of dipole elements.

5c.2 Recall that the angle at which the propagated radio wave leaves the antenna is known as the (vertical) angle of radiation and that longer distances require a lower angle of radiation.

Recall the effect of the ground on the angle of radiation.

5c.3  Recall the current and voltage distribution on the dipole and /4 ground plane antennas.

Recall the feedpoint impedances of half-wave dipoles, quarter-wave and loaded 5/8 vertical, folded dipoles, full-wave loops and end fed /4 and /2 antennas.

Recall the effect of passive antenna elements on feed point impedance and the use of folded dipoles in Yagi antennas.

Question 38

5c.4 Identify folded and trap dipoles and quad antennas in addition to those in earlier syllabuses.

5c.5 Recall that an antenna trap is a parallel tuned circuit and understand how it enables a single antenna to be resonant and have an acceptable feed-point impedance on more than one frequency. Recall that this technique may be extended to multi-element antennas such as Yagis.

Question 39

5d Return Loss and SWR

5d.1 Understand that the standing wave ratio (SWR) is a measure of the signal travelling back down the feeder expressed in terms of the standing waves caused by the reflected signal voltage (or current).

5d.2 Recall that return loss is the ratio of the forward signal power to the return signal power; normally expressed in dB.

Understand that a low SWR equates to a high return loss and a high SWR equates to a low return loss.

5d.3 Understand that the feeder loss will reduce the SWR and increase the return loss at the transmitter.

Recall that Return Loss at transmitter = Return Loss at antenna + 2x(feeder loss)

Question 40

5e Antenna Matching Units

5e.1 Understand that AMUs (ATUs) can "tune-out" reactive components of the antenna system feed-point impedance (before or after the feeder) and can transform impedances to an acceptable resistive value.

Understand that if the AMU is located at the transmitter, it will have no effect on the feeder SWR.

Identify typical AMU circuits (i.e. T, Pi and L circuits).

Question 41

6a Electromagnetic Radiation

6a.1 Recall that an e-m wave comprises both an (E) and (H) fields in phase, at right angles and at right angles to the direction of travel.

Recall that in circular polarisation, the polarisation of the wave rotates as it propagates, either a right-handed (clockwise from behind) or left handed polarisation.

Recall that this is often used for satellite communications where the orientation of the satellite is indeterminate.

Recall that the transmit and receive antennas should have the same polarisation.

6a.2 Recall that under free space conditions e-m waves travel in straight lines and spread out according to an inverse square law of power flux density and that that the field strength, measured in volts/metre, drops linearly with distance.

Numerical calculations required at item 7c1 only.

Question 42

6b Ionosphere

6b.1 Understand that the ionosphere comprises layers of ionised gasses and that the ionisation is caused by solar emissions including ultra-violet radiation and charged solar particles.

Recall the ionospheric layers (D, E, F1 and F2) and approximate heights.

6b.2 Recall that the E layer can refract (reflect) radio waves and that sporadic-E is caused by areas of highly ionised gas that can refract waves in the VHF band. Recall that the E layer supports single hops up to about 2000km.

6b.3 Recall that the F2 layer provides the furthest refractions for HF signals (about 4000km) and that the F layers combine at night.

Recall that multiple hops permit world-wide propagation.

6b.4 Understand how fading occurs and its effect on the received signal.

Question 43

6b.5 Recall that the highest frequency that will be refracted back to the transmitter is known as the Critical Frequency of Vertical Incidence (critical frequency).

Recall that the highest frequency that will be refracted over a given path is known as the 'maximum usable frequency' (MUF) and that this will be higher than the critical frequency.

Recall, in general terms how the MUF varies over the 24 hour cycle and the variation in MUF from summer to winter.

6b.6 Recall that the D layer tends to absorb the lower radio frequencies and that it tends to disappear at night.

Understand that if the D-layer absorption occurs at frequencies higher than the MUF, then no ionospheric propagation can occur.

6b.7 Recall which amateur bands will be "open" to support ionospheric propagation at different times of the day and year.

Questions will be asked on 3.5 and 21MHz propagation over the 24 hour cycle.

6c Ground Wave

6c.1 Recall that the ground wave has a limited range due to absorption of energy in the ground and that the loss increases with increasing frequency.

Question 44


7a Routes of entry into TV and Radio

7a.1 Understand that amateur transmissions can be picked up by the intermediate frequency stages of TV and radio receivers and identify related amateur transmissions.

Understand that television receivers and most broadcast radio receivers employ superheterodyne circuits and recall some typical frequencies used in radio and television receivers; i.e. 470-854MHz TV r.f, 33-40MHz TV i.f., video baseband 0-5MHz Radio i.f's typically 455-500kHz and 10.7MHz.

Understand the potential for second channel (image frequency) interference.

Question 45

7a.2 Recall that amateur transmissions can enter the r.f. stages and cause cross modulation and/or blocking.

Recall that cross modulation occurs when strong varying transmissions (e.g. a.m., s.s.b. or c.w. signals) impresses its own modulation on the wanted signal.

Recall that blocking (also known as desensitisation) occurs when strong constant transmissions (e.g. f.m. signals) cause the radio or television to be overloaded.

7a.3 Understand that mast-head amplifiers are frequently wide band devices and can suffer from cross-modulation and overload (causing intermodulation and blocking), and may also overload the TV.

Question 46

7a.4 Recall that amateur transmissions can enter audio stages via long speaker leads or other interconnections.

Understand that any pn junction within an electronic device can rectify unwanted r.f.

7a.5 Recall that passive intermodulation products can be caused by corroded contacts in any metalwork, including transmitting and receiving antennas, supports and guttering.

7a.6 Understand that ghosting is caused by external reflections and does not normally indicate a fault in the TV receiver.

Question 47

7b Filters

7b.1 Understand the construction and use of a typical mains filter.

7b.2 Identify a typical circuit of a braid-breaking filter and a combined high-pass/braid-breaking filter. Understand their use.

Understand why a ferrite ring will attenuate common-mode currents without affecting the differential-mode wanted signal.

Question 48

7b.3 Recall the use of ferrite beads or rings in internal and external filtering.

7b.4 Understand the use of notch filters including coaxial stubs as notch filters or traps in minimizing an unwanted signal.

7b.5 Understand the use of high, low and band pass filters in improving the immunity of affected devices.

Question 49

7c Field Strength

7c.1 Recall that reducing field strength to the minimum required for effective communication is good radio housekeeping. Recall and apply the formula for field strength given the ERP and distance from the antenna.

Question 50

7d Feeders and Antennas

7d.1 Recall that balanced antenna systems tend to cause fewer EMC problems than unbalanced antennas.

Recall that the feeder (balanced or unbalanced) should leave the antenna at right-angles to minimise coupling.

7e Mobile Installation

7e.1 Understand that EMC problems in motor vehicles can have serious safety implications and be able to identify suitable precautions

Question 51

7f Social Issues

7f.1 Recall the correct procedures for dealing with EMC complaints, whilst understand that although new electronic equipment should meet the EMC standards, some existing equipment may not.

Question 52

Operating Practices and Procedures

8a Packet Radio

8a.1 Recall that Packet radio transmits messages in data format that can be received directly, stored in a mailbox for reception at a later date or forwarded through a network of mailboxes.

Understand the difference between store and forward mailboxes and digipeating.

Question 53

8b Repeaters

8b.1 Recall the purpose and operation of repeaters and the correct procedures in using them.

E.g. offsets on 144 and 433MHz; time-out and reset tone; voice procedures.

Question 54

8c Intermodulation

8c.1 Understand how to identify whether the distant transmitter or the local receiver is producing intermodulation products.

8d Special Events

8d.1 Recall the purpose of special event stations and the format of special event stations.

Question 55

8e Band Plans

8e.1 Recall that band plans are produced by the IARU.

Recall that the band plans state that:

  • no s.s.b. operation should take place in the 10MHz 30m band

  • no contests should be organised in the 10Mhz (30m), 18Mhz (17m) and 24Mhz (12m) bands

  • narrow band modes are at the lower end of most bands

  • lower side band operation normally occurs below 10MHz and upper sideband above 10MHz

  • transmission on beacon frequencies must be avoided

  • transmissions on satellite frequencies should be avoided for terrestrial contacts.

Questions on beacon frequencies and satellite frequencies will be limited to the 14Mhz (20m) and 144MHz (2m) (144MHz) bands and a copy of the Band Plans will be provided.

Question 56


9a High voltage Equipment

9a.1 Understand that all equipment should be controlled by a master switch, the position of which should be known to others in the house or club.

9a.2 Understand that all exposed metal surfaces should be properly earthed.

9a.3 Understand that no work should be undertaken on live equipment unless it is not practicable to do the work dead (disconnected from the power source) and suitable precautions have been taken to avoid shock.

9a.4 Recall that thermionic valve equipment generally uses power supplies with potentials higher than the domestic mains supply.

Question 57

9b Portable operation

9b.1 Understand that operating in temporary premises and/or outdoors can introduce new hazards (i.e. overhead power lines, inadequate electrical supplies, trailing cables, damp ground, excessive field strengths).

Recall the additional safety precautions that should be taken whilst operating in temporary premises and/or outdoors (i.e. site survey, cable routing/protection, correct fuming, use of RCDs, no live working).

9c Mobile operation

9c.1 Understand that operating in vehicles and vessels can introduce new hazards (i.e. insecure equipment, long/flexible antennas, accidental shorts to earth, lack of attention to driving, r.f. induction into vehicle control circuits).

Recall the additional safety precautions that should be taken whilst operating mobile and/or maritime mobile (i.e. secure equipment, cable routing/protection, correct fuming, use of hands-free equipment, attention to good radio housekeeping).

9d RF

9d.1 Recall that the National Radiological Protection Board (NRPB) have published Investigation levels for exposure to r.f. radiation for UK amateur radio.

Recall that compliance with NRPB investigation levels will ensure that exposures are below the recommended limits and that the lowest investigation level for electric field strength is 28V/m (at 10-146MHz).

Understand that if the investigation level is exceeded the cause must be investigated and steps taken to reduce the exposure to below the investigation levels.

Question 58

Lightning Protection

9e.1 Recall that thunderstorms carry heavy static charges

Understand that the static charge from thunderclouds can ionise the air to form a low resistance path to ground, enabling a very high current to flow as a lightning strike.

Understand the risks to human life, domestic property and electronic equipment associated with a direct strike and/or the build up of static charges.

Understand that there is little that can be done to protect an amateur station from a direct lightning strike but that good static discharge systems can prevent dangerous static charges building up on antenna systems during thunderstorms. Understand that disconnecting antenna feeders from radio equipment also reduces the risks.

9f Protective multiple earthing

9f.1 Recall that in PME systems the main earth terminal is connected to the neutral of the electricity service at the consumers' premises and that all metalwork within the premises are also connected to the PME bonding point.

Recall that under severe fault conditions PME systems have the potential to cause fatal electric shocks and/or fires in amateur radio stations.

Recall that the RF earth in an amateur station should be connected to the PME bonding point in accordance with IEE Wiring Regulations to maintain safety under fault conditions.

Question 59


10 Meters

10a.1 Understand the use of multiplier resistors in analogue voltmeters, shunts in ammeters and the effect of the test meter on the circuit under test.

Question 60

10b Frequency Checking

10b.1 Recall the uses and limitations of absorption wavemeters, heterodyne wavemeters, crystal calibrators, digital frequency counters and standard frequency transmissions.

10b.2 Understand the effect of measurement tolerance, calibration accuracy and time related drift on frequency measurements and the allowances to be made for transmission bandwidths.

Question 61

10c Oscilloscopes

10c.1 Understand the purpose and basic operation of an oscilloscope. Calculate the frequency and voltage of a waveform from given data.

Question 62

10d RF Power measurements

10d.1 Understand that steady r.f. power may be determined by measuring the r.f. potential difference across a dummy load.

Understand the meaning of p.e.p. (peak envelope power) of an s.s.b. transmission and that it may be determined using a peak reading power meter or an oscilloscope and dummy load.

10e SWR. Measurements

10e.1 Identify the circuit of an SWR meter and understand its operation.

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