Chapter 7. HOW TO OPERATE A RADIO NETWORK

Topics:

7.1	Choice of Operator
7.1.1	A Good Operator
7.1.2	Control or HQ Station
7.1.3	Outlying stations
7.1.4	Stand-by operators
7.1.5	Training an operator
7.2	Operating the Equipment
7.2.1	Transceiver Controls
7.2.1.1	Clarifier
7.2.1.2	Squelch
7.2.1.3	RF Gain
7.2.1.4	Interference
7.2.1.5	USB/LSB
7.2.1.6	Earphones
7.2.1.7	Transmit
7.2.2	Care of Equipment
7.2.2.1	Controls
7.2.2.2	Microphones
7.2.2.3	Cables and Aerials
7.2.2.4	Battery
7.2.2.5	Lightening Danger
7.2.2.6	Aerial Tuning Units
7.2.2.7	Check List
7.2.3	Fault Finding
7.2.3.1	Transmitting and receiving difficulties
7.2.3.2	Battery voltage problems
7.2.3.3	Unusual Noises
7.2.3.4	Power failure
7.2.3.5	Receiver failure
7.2.3.6	Transmit failure
7.2.3.7	Physical Tests
7.2.3.8	Breakdown Proceedure
7.3	Operating the Network
7.3.1	Callsigns and Control
7.3.2	Starting a contact
7.3.3	Sending and Receiving messages
7.3.4	End of Contact
7.3.5	Phonetic Alphabet
7.3.6	Radio Jargon
7.4	Message Handling
7.4.1	Type of Messages
7.4.2	Timetable
7.4.3	Message Recording

Return to Table of Contents

There are two main requirements that have to be satisfied if you are to have a radio network which is useful, effective and efficient. The first is that the radio equipment satisfies the operational need, i.e. you can talk reasonably clearly with all the stations you want to. Ways of satisfying this requirement are covered in the previous chapters. The second requirement is equally important, it is that the network is so operated that it satisfactorily serves the needs of all its users. It is not just a case of finding someone to speak on the radio but serious consideration must be given to the choice of operator, the method of controlling the network of stations and the handling of outgoing and incoming messages. For instance, the advantage of having a well organised and clear speaking operator is that he will require far less time operating the radio. This not only means that he will occupy less time himself on the radio but also all the people he speaks to will >also require to spend less time on their radios. Less time operating means less power discharged from the battery where this is the power source. This will give a longer life to the battery, and a better performance from the transceiver, particularly where a solar charger is in use.

7.1. Choice of Operator

Your aim should be to use a person whose ability is best suited to the demands of the operating but in reality your choice may well be limited. Despite all the properties you are looking for in an operator there may only be one person available. Did you consider making provision for an additional person to be paid as an operator, see para. 5.1.5.? If operating the radio is an extra job given to an already busy person then the result may not be good. One missionary in Zaire said " I would not want to be without the radio but the time you spend operating it detracts from your other principal work." However your system will work only as well as your operators play their parts.

7.1.1. A Good Operator

The qualities to look for in a good operator should include:

1. A clear speaking voice without a too strong regional accent.
2. A good hearing ability.
3. An ability to remain calm and controlled when under pressure.
4. Enthusiasm for the job.
5. Good time-keeping. i.e. being there at the radio and prepared for the contact before it starts, also waiting until its over before switching off.
6. Patience and perseverance i.e. for repeating and confirming messages when reception is difficult.
7. Fluency in language .
8. An ability to understand the controls of the equipment.
9. A good memory. i.e. for callsigns.
10. Ability to keep accurate records.
11. A sympathetic and friendly approach to other operators while keeping the messages as concise and businesslike as possible.
12. Have good handwriting ability.

7.1.2. Control or HQ Station

This is the vitally important station. A careless operator at HQ who overlooks sending messages or does not pass them on correctly will cause more frustration than if you did not have a radio network. Here there are two options open in the choice of operator. Either the person responsible for the administration and organisation of your group does the operating himself or herself, or he or she decides to employ or delegate it to someone else to act simply as a relayer of messages.

There are advantages if your admin person becomes the operator for he may be able to answer many queries and perhaps sort out any problems immediately so that the outlying station gets its answers straight away. On the other hand it may be an extra job in an already busy schedule and through lack of time it will not be done as it should. It is not only the operating time to be considered but also the proper keeping of message records and the time spent contacting the right person and passing on the message. If the operating is delegated to someone else that person must be allowed sufficient time to do the job properly. They must be able to read accurately over the air the messages for each individual station and to take down accurately the messages coming in. Therefore they must be fluent in the language used for transmission. They must not be expected to answer questions immediately but rather relied on to pass them on correctly to the right person. Do not under estimate the time they will need to do all this properly.

The actual time taken for an operating session in Zaire between the HQ station and 4 outlying stations was typically over 1 hour. The time was occupied thus:
5 minutes to obtain the keys, go to the room, unlock room and radio desk, connect cables and set the controls ready for the contact.
20 minutes to send and receive messages.
10 minutes to ensure log book was completed correctly and to make the written copies of any messages necessary for distribution.
5 minutes to switch off, disconnect cables and lock up securely.
20 minutes to contact people for whom there were messages or questions.

7.1.3 Outlying stations

The observations about the qualities of a good operator apply equally here although there will obviously be less volume of messages to deal with. It may well be necessary to have several of your people acquainted with the operation of the radio so that in an emergency they could all cope but it is better to stick to one regular operator whose daily work schedule includes the radio operating. The operator here must learn to take his turn on the air with other stations and must be prepared to obey the instructions of the controlling station.

7.1.4. Stand-by operators

Whilst it is wise to keep to one experienced and reliable operator it is also necessary to have a stand-by who has been trained to take over when necessary. The stand-by should keep familiar with the operating procedure and the controls by operating at least once a month.

7.1.5. Training an operator

Each station should have a set of operating instructions applicable to its individual needs and its particular equipment. These instructions must be read and understood before someone is allowed to operate. Training may involve instructing an operator or teaching yourself. There is often sound technical reasons why an operator is told to use a specific piece of equipment although the reason may not be known to him. For instance the use made of one radio network was far in excess of that originally expected and as a result the cables and connections on the hand held microphones developed faults. These microphones were replaced with a desk type so it and its cable remained in one place and was rarely moved. The hand held microphones were then kept as spares at each station. However it was later discovered that an operator had changed back to the hand held against instructions because he preferred that type. To prevent the moving of desk mikes some have been fixed to the radio desk. The operator should also be told never to smoke or use a candle or naked light near a battery. The reason for this is that hydrogen gas is released from a vented battery, i.e. a car type battery, when it is being charged and if connected to a solar panel the battery will be continually charged throughout the day. The operator should be shown the equipment and the instructions and each switch or knob should be explained to him, see details in para 3.1.3. It will help if he can understand why he should or should not do certain things.

1. He should be told never to operate when lightening can be seen and thunder heard and always to disconnect the aerial and power cables after use because of danger from lightening. If he understands that lightening can come through the cables to the radio and damage it or strike the operator he will take more notice of the instructions.
2. The radio should not be operated from a battery while the battery is being charged by any other means than by a solar charger. This is because excess voltage e.g. from a vehicle alternator with a faulty regulator, can damage the transceiver.
3. No books or papers should be put on top of the transceiver while it is in use. The reason for this is that most transceivers require a free air circulation to assist cooling especially in warm climates. Black cooling fins are often found on the rear of the transceiver.
4. If the radio installation has a "fail to battery" facility, see para.3.2.1.2. then the importance of switching the transceiver off as well as disconnecting the mains must be stressed. With a "fail to battery" facility when the mains plug is removed without switching off at the transceiver controls the transceiver will automatically be connected to the battery and so remain on.

Go through with him the routine of connecting up, switching on, selecting channels, adjusting gain and tone, speaking into the microphone, taking down messages and switching off again before actually trying to transmit. Continue with this practise until it can be done without hesitation then, if possible, let him watch an experienced person going through the routine and let him listen while some are contacts are being made. Explain to him the operating procedure used at the station and let him become familiar with callsigns and expressions used. His first actual contact is best done with an experienced person at hand to help. The first experience of speaking into the microphone and knowing your voice is being heard many miles away can be quite a nerve testing experience for some people although others may find it easy. A nervous operator who is not sure what he is supposed to do will be prone to make mistakes so good instruction and training is very important. The operating instructions should be provided in a simple step by step form and kept close to the transceiver for easy reference. There should be available to the operator such things as a pen and a spare pen, sufficient paper and a clock or watch that keeps correct time. Note that simple things like these are not always instantly obtainable if the station is an isolated one. The operator must know what he is expected to do to take care of the equipment, see para 7.2.2., and what his responsibilities in recording and passing on messages are, see paras 7.3 and 7.4. The operating instructions should include a check list of things he must and must not do, including what to do if there appears to be a problem with the equipment, see para 7.2.3.

7.2. Operating the Equipment

There are many different controls and facilities on transceivers and these vary according to the model. Always be aware of any facility which is peculiar to your particular station whether it was put in by the manufacturers or modified by your networks engineer. However there are certain basic rules that will apply to all equipment.

7.2.1. Transceiver Controls

The most common and essential controls are listed in the chapter on transceivers see para. 3.1.3. Read again the descriptions given there and then note the following operational points. The handbook for your particular transceiver may give special operating instructions e.g. if the transceiver contains thermionic valves or crystal ovens it should be switched on 5 to 10 minutes before use.

7.2.1.1. Clarifier

The operator may need to alter this control for each station he listens to so as to get the best pitch or sound for his particular hearing. The pitch that sounds clear to one person may not be so clear to another.

7.2.1.2. Squelch

This has often caused problems where its function is not understood. When the transceiver is switched on the Squelch should be OFF. That is either switched OFF if the control is a ON/OFF switch or if it is a variable control it should be fully rotated so that noises come from the loudspeaker. Then after all the other controls have been set e.g. channel selected, audio gain adjusted the Squelch can be set to inhibit the loudspeaker background noise if required. However in many instances operators have set the Squelch threshold too high and stations have not been heard. The author found that it was rarely correctly used in his network and to avoid problems removed it from most sets, see para. 5.2.5.4. on modifications.

7.2.1.3. RF Gain

This should be set for maximum to start with then gradually reduced for the best sound. If the RF gain is set too high then the signal received from a nearby or strong station can sound distorted or even appear to be going off and on. Operators listening to such strong signals have told the station transmitting to them that there is a fault in their transmitter whereas the problem was their own RF Gain control was set too high. Be careful with this control because if someone with a weak signal calls in when the RF Gain is turned down they may not be heard. The operator should get to know all the stations on his network and by experience learn which ones will need the RF turned up and which will need it turned down. Make it the rule always to commence with it at maximum and adjust as necessary.

7.2.1.4. Interference

This can be caused by nearby transmitters although they are not operating on the same frequency. In this case best reception conditions can be obtained by reducing the RF Gain as far as possible whilst still enabling the operator to hear the station with whom he is in communication, any loss of volume can be compensated by using the Audio Gain or Volume control.

7.2.1.5. USB/LSB

If the stations are equipped and permitted to operate on both upper (USB) and lower (LSB) sideband then if there is interference on one sideband it may be possible to use the other. First check the other sideband to see if it is free from interference and is not in use by someone else. Then inform the other stations and suggest they move on to it. After the contact is over return the USB/LSB switch to its normal position for the next contact.

7.2.1.6. Earphones

At stations where some of the other stations are difficult to hear then earphones may be provided. If you have more than one operator you will have to decide whether each operator should have his own earphones on grounds of hygiene. The cable on the earphones can easily become twisted and in knots so be careful and prevent this from happening.

7.2.1.7. Transmit

It is good operating practice to press the transmit button before beginning to speak in to the microphone and also to cease speaking before the button is released. The operator must always speak clearly and reasonably slowly into the microphone but must never shout. Shouting will only distort the signal especially if done close to the mike. If there is a "transmit" light which flashes as the operator speaks he should watch this light as it ought to go out during the slight pauses in his speech. It will be necessary to adjust either the loudness of the voice or the closeness to the mike to ensure that the light goes on and off in sympathy with the voice. When the distant station says they are not receiving the transmission the instinctive reaction is to speak louder. However shouting into the microphone may cause the Automatic Level Control circuits to operate in the transmitter and so make the transmission less intelligible to the distant receiver. Some improvement in communication can be made on a "trial and error " basis. For example one operator can ask the other operator "do I sound better on this first transmission or on the second transmission after I have changed my position?" The success of such tests will depend on the organising ability of the operators.

7.2.2. Care of the Equipment

Operators must be made aware that the equipment they are using needs to be handled carefully. It is often expensive and sensitive but used properly most modern communication equipment should stand up to daily use for a long time. In addition the operator may be asked to do some routine maintenance, see para. 8.6.

7.2.2.1. Controls

Controls and knobs should only be adjusted when necessary, it often happens that operators waiting their turn to transmit will fiddle with the controls turning them first one way then another. Knobs and indicator lights have worked loose and been broken because of this kind of treatment. So the rule must be to touch the controls only when necessary, e.g. to hear more clearly or to change channels.

7.2.2.2. Microphones

Microphones are delicate instruments and have often been treated badly, sometimes being pulled to reach across a room for someone else to speak resulting in broken connections. So the rule must be that only the operator or the person sitting in his chair does the speaking and in the case of a desk mike it must be left on the desk or the table close to the transceiver. It may be wisest to have it fixed in position on the desk or table and it should always be left connected to the transceiver. Hand held mikes are very often passed from hand to hand or left swinging loose on the end of their cables. The cable can become worn and broken just by the continual handling. They are best kept for use with mobile equipment or as a spare microphone.

7.2.2.3. Cables and Aerials

Cables and leads such as those coming from the power source and from the aerial should not be allowed to become tangled up or twisted into knots. They should be handled with care the same as the rest of the equipment. In particular watch the plugs or connections on the ends. When disconnecting an aerial cable , for instance, make sure that the coupling ring see Fig.6.5. has been fully unscrewed before pulling it from the socket. Never remove a cable by pulling it but hold on to the connector on its end while removing it. Be careful not to cross thread the connectors. If there is more than one aerial, label each aerial cable with the frequency and channel number it is used with. If there is an aerial switch in use leave the aerials connected to the switch all the time, disconnect the transceiver from the aerials by using the connecting cable between the transceiver and the switch. This cable is best connected and disconnected at the aerial switch rather than from the transceiver socket. The actual aerial should be checked visually regularly but particularly after storms and high winds. No tree branches should be allowed to obstruct it.

7.2.2.4. Battery

Never switch on a transceiver when it is only connected to a solar charger i.e. when the battery has been disconnected. The acid level of a vented battery must be checked regularly at least once a week. If the level is down it must be filled up with distilled water or other substitute e.g. rain-water collected in a plastic sheet. The battery voltage should be measured regularly if there is a voltmeter available to do this. If voltage is too low the transceiver must not be used until the battery is fully charged again. It has been known for an operator whose battery was flat to get a second battery and connect it in series with the radio battery with the result that 20 volts was applied to the 12 volt transceiver causing serious damage. When transmitting, the battery voltage is low if it goes down below 11 volts. Receiving does not require so much power so if the voltage is too low to transmit it may be possible to listen and receive messages.

7.2.2.5. Lightening Danger

In areas where thunder storms occur frequently it is a good practice to disconnect the aerial when the transceiver is not in use. Where thunderstorms only occur in certain seasons some operators will only remove the aerial during these seasons but this is not an entirely reliable scheme as the start and finish of a season is not always well defined. Therefore the practice of always removing the aerial at the end of every contact is the recommended practice. The HQ station of one radio network in Kenya periodically reminds the operators of the other stations to disconnect their aerials after using their radios. It is also good practice to disconnect power cables especially mains cables and battery cables where the battery is being charged by solar panels on the roof.

7.2.2.6. Aerial Tuning Units

The operator should be warned that high voltages occur at the aerial terminal of transceivers which incorporate an aerial tuning unit (ATU). RF burns can be received if the terminal is touched during transmission. With these units when the frequency in use is changed the ATU will need retuning as per instructions for that particular unit.

7.2.2.7. Check List

This is an example of instructions given to stations on "Looking after your radio." Always follow the operating instructions.

• Never forget to remove power and aerial cables at end of contact.
• Look after your battery. Keep acid level topped up with water as required. Check it once a week.
• Keep battery lugs free from corrosion and covered with grease.
• Keep the cabinet, desk or table clean and free of dust and pieces of unnecessary paper etc.
• Make sure nothing blocks the ventilation around the radio when it is in use.
• If the radio is covered with a dust sheet when not in use always remove it completely before commencing contact.
• Keep the radio room clean and secure.
• Do not handle the controls more than necessary, especially do not twist knobs etc. round and round when waiting by the radio.
• Do not allow unauthorised people to use the radio.
• Keep an eye on aerials and cables especially after storms.
• Keep an eye on your solar panel e.g. make sure it stays clean and trees do not grow up to shade it.
• Keep to the one operator but have someone trained as a standby.
• Keep operating instructions accessible.
• In case of breakdown of the radio get message by some means to HQ giving as much information as possible.

7.2.3. Fault Finding

An alert radio operator can often give advance warning of the onset of a fault in the radio system by reporting anything that is unusual. This can cover such symptoms as a station becoming persistently weak, apparently distorted or of gaps occurring in the transmission. These observations should be reported back to the station with the problem and to the person responsible for radio maintenance. However a operator should not be over enthusiastic in telling another station that they have a problem until he has ensured that the apparent problem is not being caused by his own equipment. For example, is it only one station that sounds distorted ? If all the others sound distorted as well then the problem well may be in the operators own equipment. Again if it is a strong station that sounds distorted then is the RF Gain set too high at the receiving station? see para.7.2.1.3. If an operator is told that his own transmission sounds weak or distorted then there are certain checks he can do himself. The following simple tests are given so that the operator can render "First Aid " or advise the radio maintenance person of the possible cause of the fault. Note that in the event of a possible fault in the radio network the radio technician responsible may wish to limit the operators actions to observation and certain permitted actions only. When there is a fault which the operator thinks is within the transceiver he should be told never to remove the cover to inspect the interior unless he has been given precise instructions by the technician to do so. If a component inside the transceiver is at fault there is little an unqualified person can do either to trace the fault or to fix it. Indeed such a person has been known to cause further damage to the transceiver in his desire to help.

7.2.3.1. Transmitting and receiving difficulties

1. If the operator is having difficulty hearing and making himself heard:

Check (1) That the power light or indicator comes on at its usual brightness. If it is dull then the battery voltage is low and it needs to be charged up again before using the transceiver .
Check (2) That the power light remains bright when the operator is transmitting. If it goes dull the battery voltage is too low for transmission although it may be all right on receive.
Check (3) That the TRANSMIT light or indicator flashes as the operator speaks. If it does not try using the spare microphone. If the TRANSMIT light then works the fault is in the first microphone. If it still does not work there is a fault inside the transceiver.
Check (4) Repeat Check (3) on all the channels on the transceiver. Note if the fault appears on all channels or one particular one.
Check (5) That the aerial appears to be in good order i.e. no parts are broken or hanging down and no tree branches obstructing it. If the aerial is down try to reinstate it to the original state or ask HQ for any new pieces needed.
Check (6) That the aerial cables and connections are not damaged. If there is a visible broken connection the operator may be able to do a temporary repair then inform the person responsible for maintenance and wait for his instructions.

7.2.3.2. Battery voltage problems

If battery is charged by solar panels.

Check (1) That the surface of the panel is clean.
Check (2) Observe any charging indicator light or meter where fitted .
Check (3) That the duration of daily use has not exceeded the recommended time.
Check (4) Suspect lightening damage possibly to diode.
Check (5) Allow battery time to recharge see para.3.2.3.4. If battery does not recover inform maintenance person. If battery is charged by other means.
Check (1) That the generator or mains battery charger is giving the necessary charging current.
Check (2) Allow battery sufficient time on charge to recover, if it does not suspect battery is too old or damaged in some way, see para 3.2.3.3 on battery life etc.

7.2.3.3. Unusual Noises

For any unusual noises coming from the loudspeaker, first of all try:

Check (1) Disconnect the aerial from the transceiver itself to see if the noise stops. If it does these are strong external signals and there is nothing wrong with the transceiver.
Check (2) If there is still a whistle or warbling tones etc. even with no aerial connected then reconnect it and try reducing RF and AF Gain controls to stop the whistle etc. so that you can receive, then inform radio maintenance of the problem.
Check (3) If there is a loud hum during receive:
(a) where radio battery is charged off the mains, ensure that the mains battery charger is switched off while operating.
(b) where there is a hum on a mains operated transceiver there is a possible fault in the transceivers own mains power unit.

7.2.3.4. Power failure

There is no power at all in transceiver after it is connected and switched on. This is shown by the power light being off and no sound coming from the loudspeaker on receive.

Check (1) For a battery operated set that battery leads have not become disconnected and that the battery is still there! For a mains operated one that there is actually power in the radio room.
Check (2) That the fuse has not gone. Replace it if necessary with a good one , if this then goes there is a fault inside the transceiver so do not replace again but inform HQ by some other means that there is something wrong with the transceiver.
Check (3) That plugs and cables have no visual damage. If a faulty cable is suspected inform maintenance and ask for replacement.
Check (4) If there is a simple explanation. For example where the power lead is normally plugged and unplugged from the wall socket and the other end is permanently connected to the transceiver. It has been known for someone to disconnect it both ends and for the next person to come in and plug into the wall socket without realising the other end is not connected to the transceiver.

Note that things like this can easily happen so always check the ordinary and the obvious when there appears to be a problem!

7.2.3.5. Receiver failure

If there is power in the transceiver i.e. the power light is on at its normal brightness, but there is no sound coming from the loudspeaker.

Check (1) That all the controls have been set to correct position as in the operating instructions. If RF gain or Squelch is incorrectly set or the Channel switch is wrong for instance.
Check (2) That the aerial is correctly connected and if using an aerial switch that it is switched correctly.
Check (3) That the aerial or its cables are in good order.
Check (4) If the above are all correct and there is still nothing coming from the receiver try transmitting and see if the transmit light flashes. If it does there may be a fault in the receive side only. Try sending a message to say what has happened to your HQ station.

7.2.3.6. Transmit Failure

If the receiver is working all right i.e. the power light is at its normal brightness and other stations can be heard at their normal level but it is obvious that that they are not able to hear your transmission.

Check (1) That the microphone is correctly plugged in and that the transmit light flashes when speaking. If light does not flash try spare microphone. If the light still does not flash there is a fault in the transceiver or the battery voltage is too low for transmitting so:
Check (2) That the battery voltage is good. Note if it is low i.e. below 11 volts, it may be possible to receive but not to transmit.
Check (3) If the voltage and transmit light are correct check that aerial has not been damaged, one half hanging down or broken off for instance. Note that it is possible to receive on a long piece of wire but to transmit needs an aerial properly tuned and the right length for the particular frequency.

7.2.3.7. Physical Tests

Faults often take the form of disconnected or broken wires. These can either occur at the point where the wire is soldered or screwed into a plug or further along a piece of cable. Providing the action is gentle the operator can move the cables about, one at a time, especially where they enter a plug or socket to see if the transceiver will start working again. If the transceiver can be made to work by holding or twisting the faulty cable then a message can be sent to request a replacement cable or the help of a technician. Instructions will have been given to ensure the acid level of a vented battery. This is so often overlooked that it cannot be said too often. Again and again it is not till the voltage falls sufficiently to cause a problem with the radio that the battery is checked. Also the wires from the transceiver can corrode away and break the circuit where they are connected to the battery. A movement of these wires will show if there is a problem.

7.2.3.8. Breakdown Procedure

All stations should have instructions as what to do in case of breakdown. This will depend on the particular situation of each network and sometimes of each station. Where there are reliable repair facilities nearby arrangements should be set up by your group or organisation when the equipment is installed and the operators should be aware of them and have available a technical manual for the technician. Where there are no such facilities operators must await instructions from HQ. HQ operators must take note of any stations who do not answer when called in and report this to the person responsible for maintenance in the network. A few contacts may be missed for reasons such as sickness or flat batterys but if a station remains off the air for longer than normal it must be assumed that it has broken down and steps must be taken to find out what has happened. The HQ operator should note that it may be possible for the missing station to receive even though it cannot transmit so the operator should continue to call them in and should send any messages or instructions required. However bearing in mind the possibility of a complete breakdown instructions should also be sent by whatever other means are available.

7.3. Operating the Network

It is possible to treat a radio contact in the same way as a telephone conversation with the addition of the word OVER at the end of each portion of speech. If there are only two stations talking to each other this is no problem. However the problems arise when there are three or six or maybe twelve stations waiting their turn to speak. In these cases there must be an orderly procedure to follow and everyone must understand it and keep to it. The following notes are drawn from practical experience and work well if carried out correctly. The important thing is to have a recognised pattern to your radio contacts that all your operators can respond to and cope with.

7.3.1. Callsigns and Control

Each station should have its own official call-sign e.g. 9SD67 or 9SD47, although in practice only the last part is used e.g. 67 and 47. These callsigns will be allocated by the licensing authorities of individual countries. A list of the callsigns belonging to the network should be kept at each station and all operators should know and use them rather than the place names. One station, which is normally the HQ station, should be in control of the network and all others should obey his instructions. When calling a particular station the operator should say this number first followed by his own e.g. 67 from 47.

7.3.2. Starting a contact

The situation exists in one African country where the same radio frequency channel has to be shared by several different organisations. In such situations there should be a timetable which gives you the channel at specific times and days. Even if this is the case it is not always adhered to by all users. When more than one pair of stations are trying to speak at the same time the result is often that nobody can really understand what the others are saying. This "law of the jungle" usually resolves itself into some informal agreement between users so before the operator starts transmitting he should first listen on the channel. If it is in use he can remind the users that it is his time and unless they have very urgent messages, when some immediate arrangement can be made, then he should be given the use of the channel. Assuming the channel is clear the controlling station should begin by calling in each station in turn by their callsign, asking them if they have any messages and telling them to standby to receive any messages. One station may have a message for one of the others as well as the HQ station in which case it should clearly say so then that particular one will know to wait for it.

If there are no messages incoming or outgoing for a particular station it could leave the net after all stations have been called in. In practice most stations remain to listen to all the others as this is a source of news, especially in remote locations. When all stations have responded to HQs call they should be asked by callsign one after another to pass their messages to HQ and to be ready to take down incoming messages. This should be done in an orderly fashion with each station taking its turn under the control of HQ. They must wait for their number to be called and never try to jump in on top of someone else. Never forget that only one person at a time can transmit and expect to be understood. Two stations talking at once makes for confusion! The HQ or the controlling station should make a note of any stations who do not reply to his call and inform the necessary person.

7.3.3. Sending and Receiving messages

Each message should be as clear and concise as possible. It should be read clearly and not too fast into the microphone. Never shout as this can cause distortion. The operator should begin by saying the callsign of the station he wants to talk to followed by his own. Finish a message distinctly by saying the callsigns again followed by the word " Over" or "Over to you". Confusion can be caused if the operator does not finish clearly but lapses into silence so that the other is not sure that he has finished. Also long pauses and hesitions during transmission can give the impression he has finished or that there is something wrong with the transceiver. Keep all messages to essential matters. Remember others are waiting their turn. Take care that the messages have been clearly understood on both sides. If in doubt the receiver should read back the message to the sender to check for errors in reception. Where reception is difficult and noisy it is essential to do this. If there is difficulty in understanding certain words e.g. names of peoples and places or medical terms, ask the operator to spell them using a phonetic alphabet. see para.7.3.5.

7.3.4. End of Contact

When each station has given and received all its messages it may want to finish and switch off. It should make this clear by using the expression "47 signing off" or "47 going clear". If the operator is finished but he wants the others to know he is still listening he can say "47 standing by". If the operator wants another station to wait for him he should say "can 46 stand by for 47". These phrases may sound like operators jargon but if used and understood by all they can be an aid to communication. See para.7.3.6. for list of words often used by radio operators. When all messages have been transmitted and received HQ, the controlling station, should pause and check for any stations that were missing at the beginning. He should allow enough time for any delayed station to call him when the others have finished and should give missing ones one more call. If these stations still do not reply then the operator should transmit the messages to them because they may be able to receive. There have been many cases of transmitter failure whilst the receiver has remained serviceable. Also when a battery is discharged there is often sufficient power to operate the receiver but not enough to transmit. Finally the controlling operator should indicate clearly that he has finished by saying "67 going clear" or "67 signing off" before switching off his equipment.

7.3.5. Phonetic Alphabet

To spell out words using this alphabet use a well-known and easily recognised word beginning with the letter that you are sending. e.g. CORBETT spelt out in this manner becomes Charlie, Oscar, Romeo, Bravo, Echo, Tango, Tango. It is possible of course to use any suitable words familiar to the operators but there are some phonetic alphabets which are well known and international and can be heard on channels used by aircraft.

Here is one alphabet in common use:

7.3.6. Radio Jargon

It is possible , of course, to talk on the radio as in normal conversation but it sometimes helps in communication to use certain set phrases or words. These must be understood by everyone using them and not thrown in because it is thought it sounds good. Words like "negative " for "no" help because a little word like no is easy to lose amongst the noise in poor reception conditions. "Negative copy " makes it clear that the message has not been understood and most people recognise the term " Roger" as meaning message received and understood. Here is a list of radio expressions commonly heard.

"Over" Short for "over to you" meaning the operator has finished speaking for the moment and is waiting for a reply. Always use it to indicate that the message is finished to avoid any doubt.
In French "A vous" also has the same meaning and in Lingala "na yo".
"Go ahead" or "47 to 67 Go ahead" is also used with the same meaning.
" Roger" message received and understood.
"I copy" or "I read" has the same meaning. Also the French "capte" or "bien capte".
"Negative copy" Message not received or understood.
"Negative " No, that is not correct.
"Affirmative " Yes, that is correct.
"Stand by" Please wait for further messages.

7.4. Message Handling

The technical side of the radio network can be working well but the purpose of the network is to pass messages. Therefore the handling of messages before and after transmission over the radio is just as important as the transmission. Messages received on the radio must be passed on accurately and quickly to the person they are intended for and requests received for information or for supplies must be dealt with accurately and efficiently otherwise the network is not satisfying its purpose. In practice it is often found that once a network starts operating the type of message and requests far exceeds the original agreement.

7.4.1. Type of Messages

The Government of the country may place certain restrictions on the use which can be made of the radio network. In addition every effort should be made to define what types of messages your organisation will permit to be sent over the radio network and what services can be requested. Unless there is general agreement on these subjects the advantage of a radio communications network can become a source of discontent because messages are not being passed on and requests for goods etc. are not being met. Messages could be classified as URGENT or ROUTINE. However in practice some originators of messages tend to classify all their messages as URGENT. This becomes obvious to the person receiving the messages who will then handle them as routine so defeating the aim of the classification. An analysis of the messages passed by expatriate personnel over a mission network during a three months period in 1987 is given in Table 7.1. Of these 679 messages 388 were to HQ and 291 from HQ. The network consisted of 9 stations spread along 1700 kms of the River Zaire. It was used to a much greater extent by the national church for which no figures are available.

Table 7.1.

When a lone expatriate is working in a remote location it is helpful for them to have some time on the air for general conversation in addition to the normal message time. This has to be when the channel is not busy, usually a Sunday afternoon. It is often people in similar situations i.e. living alone in remote places, who arrange to talk together.

7.4.2. Timetable

The existence or otherwise of a timetable for different organisations to use the same channel has been discussed in para.7.3.2. Your organisation may wish to further subdivide its own time between different departments. For example one mission allocated 0900 to 1000 Education, 1000 to 1100 Medical and at 1200 General Rendezvous for all other matters. If your network covers a very large area it may be necessary to subdivide it on a regional basis. For example each region could be allocated a certain time to deal with its own regional business and a certain time when it could contact the central HQ control for other matters. Never change an existing timetable that works until you are sure that the channel will be free for you to use at the new time. This can be done by simply listening on the channel for several days to see at what time it is in use.

7.4.3. Message Recording

A log book is necessary at each station as a written record of all messages sent and received. This may be a legal requirement by the Government of the country who may prohibit the use of a loose leaf type of book. Duplicate pads are available which provide one page to be left in the book as a record and a second carbon copy on a tear out page for passing on to the person to whom the message is addressed. Even if there is no such legal requirement the written record is essential to ensure the smooth running of the network. A verbal message is easily forgotten or mistaken! Before the contact begins the operator should write his name the date and time across the page and then the outgoing messages. There should be columns to show if the message is to or from a station, the message itself and then the action taken in response to the message. The HQ operator can give each individual outgoing and incoming message a serial number which he informs the other stations of and this can be used as a quick reference for any future associated information. The log could take the following form:

There should be a person on each station who is responsible for seeing that all messages are passed on. The person need not necessarily be the operator. Where practical a person should take the log book around the personnel of the station after each contact so that recipients of messages can sign to acknowledge receipt. Also they can enter messages they wish to send in the book in their own words. Many errors occur because the operator sends his own interpretation of the message and does not faithfully read it as written. An alternative arrangement is for the log book to be available to everyone to see at a certain time and place each day. When receiving messages some operators write them down rapidly on scrap paper and then copy them into the log book afterwards. When this happens the log should be written up as soon as possible after the contact while the messages are fresh in the operators memory.