CT Radio FAQ

CT's Radio FAQ

This FAQ is intended primarily for newcomers to radio so the terms are deliberately made straight-forward.
Sometimes this may be at the loss of some level of specific technical detail.
CT Staff realise that some readers may have a signifiantly more extensive knowledge of radio and may find this FAQ too simplified in places.

Please report any technical errors, or typo errors to a member of the CT Staff Team (Admin or Moderator)
We would be happy to hear suggestions or requests for additional FAQ items (or submissions of items for inclusion ).

Click on any Topic or Question below:

Q - What is CB, and do I need a Licence?

There are three categories of Hobby Radio in the UK. Plus, in addition to the three Hobby categories, there are many other radio users which vary from Maritime to Business Radio (includes Store Security people, or even Top Gear car to car type communications), plus the official users such as Fire, Police, Coastguard, Military, Air etc. etc.

[1] PMR446

- These are low-powered hand-held radios (walkie-talkies) that transmit in the UHF (Ultra High Frequency) band.
They are sold as sealed units with a built-in aerial and have a power limit of 500mW (half a Watt). They're intended for very short range operation and ideal for children to "play radio" with. No licence is required and no preparation needed to use them: Open the pack; put the batteries in; and away you go.

Apart from use as Toys, there are some social groups that use PMR for event management and a few people that use them much like CBs, even to the level of try for Long-distance (DX) contacts.
Any modification to a PMR radio, even changing the aerial, negates the "Type Approval" licence and makes their use illegal.

[2] Licenced Amateur ("Ham") Radio

- This category covers all the "Ham" Radio activity. To operate an Amateur Radio you need a Licence from Ofcom which is obtained by passing the relevant RSGB (Radio Society of Great Britain) Examination. The entry level licence is the Foundation, then the Intermediate and the Full licence. Further information regarding training and obtaining an amateur radio operator licence is mentioned as a separate topic in this FAQ.

[3] CB Radio

- There are two distinct groups for CB type radio in the UK. Put simply, they are the Legal Users and the Illegal Pirate / "Freeband" Operators.

[3.1] Legal CB Radios

There are two bands of CB Frequencies allocated for legal CB radio use in the UK:
- The first was legalised in November 1981 and operates on a unique frequency range of 40 Channels (27.60125 MHz to 27.99125MHz, with 10kHz spacing). This original UK band is most commonly known now as "the Muppet Band" or sometimes the "27/81" Band.
- In 1991, the UK complied with a directive from the EU to provide a level of standardisation in CB usage by legalising the CEPT (European) forty channels. These are in the "Mid band" (26.965MHz to 27.405MHz), exactly the same frequency as used in the USA, but FM only. This Band is known as the "EU" Band or "Mids"/"Mid Block".
Different parts of Europe have some additional legal bands (some even allow AM, and low power Sideband (SSB) on some frequencies), but all EU countries now have this common "Midband" or "EU/CEPT Band" on FM.

Anyone can now use either of these bands in the UK and no licence is required. The legal requirement is that only radios conforming to the relevant Ofcom Type Approval standards are used, no modifications are permitted and radios must not exceed 4w transmit power (in the UK). Any additions such as Linear Amplifiers ("Burners" or "Boots") are illegal as is any radio that can transmit on any Mode other than FM (no AM, no USB or LSB).

As Modifications automatically negate the "Type Approval" of any radio, older 27/81 radios retrofitted with the newer CEPT/Mids channels are technically illegal. However, the likelihood of detection or being charged whilst using any FM set at 4w is extremely small, unless the radio set-up is causing interference and complaints have been made to the official bodies.
[3.2] "FreeBand" or "11m Pirate" CB Radios

The term Freebanding has become rather widely used to include anyone (in the UK) using any frequency, mode or power other than the legal 4w UK-FM and CEPT-FM. So that would include anyone with a High button on their CB, or anyone still using an ancient American 40 Ch. CB on AM, and certainly anyone outside the basic channels on a pre-81 Concorde, Tristar or Cobra GTL type CB radio.

But the more accurate definition of a "Freebander" is someone that uses SSB (Single Side Band), typically USB (Upper Side Band) and the calling-channel 27.555Mhz in the 11-Metre band with the intention of making DX (long distance, International) contacts.

Very long range contacts on the this band are achieved using a phenomenon commonly called "Skip" whereby radio waves (in effect) bounce off the ionosphere and can travel great distances. Contacts between the UK and Australia have been achieved on this band when the atmospheric conditions are right.

Typically "Skip" on the 11m band is more likely in the Summer months and as such, the hobby becomes much more widely used between about April and October.

Some hobbyists on this Band have very expensive equipment costing many hundreds or even thousands of pounds. They may have very high power Amplifiers on their radios and may even use directional ("Beam" type) antenna systems.

NOTE: However, regardless of how widespread it is, it must be stressed that all "FreeBand" activity is still technically illegal and that anyone identified by Ofcom using this type of equipment and these frequencies is liable to prosecution, their equipment will be confiscated and they may be given a fine or other punishment as the Court might decide. But, unless the station is actually causing interference and Ofcom receives complaints, there are very few reports of the Authorities actively tracking or seeking such stations for prosecution.

Q - How to set up a straight-forward CB station

Most CB radio stations are either installed in a vehicle ("Mobile") or at home ("Home base"). The majority of Home base stations also use a 12v mobile type radio, but powered by a transformer from the house Mains supply.

Mobile Installation

The simplest Mobile CB installation will comprise the radio and a suitable aerial, but there are a few points that need to be considered before just "banging a rig in the motor". Any Mobile CB radio will require a power connection to the 12v vehicle supply (some modern CBs will also automatically detect and accept HGV 24v power). A standard power, legal CB can simply be fitted with a "cigar-lighter plug" on the end of the lead and the power obtained that way, but a high powered radio could demand more power than the lighter socket can provide, thereby causing possible damage to the car or the radio, or even creating a fire risk.
Taking the power for the radio from any circuit within the car may also allow interference from other electrical items to cause noise on the radio so, for this reason, many people recommend taking the power for the CB directly from the battery terminals.
Regardless of where the power is taken from, always ensure the CB is fitted with an appropriate fuse, and is mounted where it cannot fall or otherwise distract or interfere with the driver.

The second thing that is needed is an aerial. These vary from two feet (60 cms) long right up to nine feet (2.75m). Fairly obviously the longest ones are not really suitable for use while Mobile, but can be carried in the car and erected when parked on a hilltop or similar (Static Mobile)
There are Three main methods of fixing an aerial to a car:

A "Mag Mount" - where the aerial is fixed to a large magnet which, in turn, is placed on the boot-lid or roof. The aerial lead is then usually passed through a door into the vehicle and then into the back of the radio.
A "Boot/Trunk/Gutter Mount" - where a mount for the aerial is clamped to the edge of the bootlid, or hatchback, or onto the gutter rails (if the vehicle has them). Like the Magnetic Mount, the aerial lead is then passed into the vehicle through the luggage are or through a door. This type of mount is more secure and cannot be stolen quite so easily but, the downside, it is not as easy for the owner to remove overnight or when parked in a high-risk area.
The "Roof Mount" (sometimes called a "Snail Mount ") - this type of fixture requires a hole to be drilled through the vehicle skin (roof, bootlid, wing ("Fenders" for our American readers) or any other surface. This type has the advantage of being the most secure and also provides the most efficient electrical connection as the vehicle body is used for the Earth or "Ground Plane". The obvious downside is that it involves cutting the vehicle and routing the cable afterwards can present some difficulties (for example, if the hole is drilled in the vehicle roof, then the wire has to be passed behind the cab headlining).

The final point to remember when installing a radio in a vehicle is that although the aerial may claim to be "pre-SWRed", it is always wise to check (see separate FAQ regarding SWR).

Home base Installation

The main difference between a Home base and a Mobile installation is the provision of power. Unless you are installing a specific Home base type radio that was designed for home use only and has a Mains Power Lead on it, the mobile radio being used at home typically needs 12v DC (actually it is 13.8v) and the (UK) household supply is 230v AC. So there is an obvious need for a transformer to provide the appropriate voltage and power to the radio.
When selecting a Power Supply Unit (PSU, Transformer) it is important to ensure that it has sufficient amperage to power the radio you intend using. A standard 4w legal CB will require about 3a (or even 2a will do) but a FreeBand radio will need a bigger PSU. Typical SSB CB sets (President Lincoln, SuperStar3900, Cobra 148, Ranger 2950) usually need about 10a and high-power sets like the Ranger 2970, the Galaxy, or the Magnum S9 will need a 25a to 30a PSU.

A significant advantage of the Home base is that (usually) a much more efficient and larger aerial can be used. There are any number of different types, shapes, sizes and prices of Home base aerial, from about £25 to many hundreds of pounds, but even the cheapest is likely to provide better performance than a Mobile aerial. Most CB Home base aerials are vertical rods, usually between eighteen and twenty-three feet high, so care needs to be exercised when installing them and good safety practice should always be employed when using ladders and power tools while mounting things like base aerials.

NOTE - You will frequently see mention of both "AERIAL"s and of "ANTENNA"s (or even ANTENNAE).
They are the same thing. The word "Antenna" is the American word for what the British call an "Aerial".

By the way: "ARIAL" - is a Typeface Font, and "ARIEL" as an air-elemental fairy mentioned in Shakespeare's writings!

Only an "AERIAL" is a piece of Radio Equipment

q - What do the Knobs and Switches on my Radio do?

This section provides a brief guide as to what the controls do on a typical "10 meter Radio".

Transceivers vary hugely in the number of knobs, button and switches that they have, from a humble 40 Channel CB27/81 Set to a full-on, top-end HF set.

For the purpose of this FAQ Section, we're using the mythical CharlieTango SSB DX 3000 Radio.

Remember, not all 10m Radios have all the functions of the CTSSBDX3000, and some sets have other functions that are not on this model.

A. METER: This meter indicates received signal strength, transmitter RF output power and SWR level.

B. S / RF-SWR-CAL: Switch This switch selects the mode for the meter. In the S/RF position, the meter indicates received signal strength and transmitter RF output level. In the SWR position, the meter indicates SWR level. CAL position is used to calibrate the meter prior to read the SWR level

B.1 to check the SWR of your antenna system:

Place the CW/FM/AM/USB/LSB switch to FM

Set the S/RF-SWR-CAL switch to CAL position

Push and hold the microphone PTT (Press-To-Talk) button

Rotate SWR CAL control until pointer reaches the CAL position on the meter.

Place S/RF-SWR-CAL switch to SWR position

Read the SWR level on the meter.

C. NB / ANL - OFF: Switch When the switch is placed in the NB/ANL position, both Noise Blanker and Automatic Noise Limiter circuit are activated. The Noise Blanker reduces repetitive noise such as ignition interference, and ANL eliminates type noise.

D. RB / ECX - OFF: Switch When the switch is placed in the RB/ECX position, both the Roger Bleep and the microphone Echo Function are enabled. In the OFF position, both functions are disabled.

E. +10 - OFF: Switch When the switch is placed in the +10 position, the frequency of the radio is raised by 10kHz (one channel). This allows the radio to operate on the frequencies known as the "Alphas" (between Channels 3 & 4, 7 & amp; 8, 11 & amp; 12, 15 & amp;16, 19 & amp; 20).

F. LOCAL / DX: Switch When the switch is in the LOCAL position incoming signal are attenuated (reduced) so that only the most powerful, stronger stations are received. In the DX position, the attenuator is disengaged, allowing fainter, distant stations to be heard.

G. TALKBACK - OFF: Switch This feature allows you to monitor your own voice in order compare microphones, or set adjustments on a microphone for optimum performance. When the switch is in the TALKBACK position any speech into the microphone will be heard through the radio speaker. This may cause Feedback if the volume is too high and it is recommended that a pair of headphones is plugged into the EXT.SPK socket on the rear of the radio when this function is used.

H. CHANNEL DISPLAY: The numbered LED indicates the selected Channel.

I. TX / RX: Indicator The TX / RX indicator is lit Green when Receiving and in Red when Transmitting.

J. TALKBACK: Indicator The TALKBACK indicator is lit Orange when the TALKBACK function is engaged.

K. HIGH SWR: Indicator The HIGH SWR indicator is lit Red if a dangerously high SWR is detected (above 3:1). This usually indicates a fault with the aerial system and the radio should not be used to Transmit until the aerial has been checked and the SWR lowered. Transmitting when this indicator is lit, especially at higher power, may seriously damage the radio.

L.1 OFF / VOL / SQL: Knob INNER To turn the radio on, rotate the inner knob past the click, then continue to rotate until a comfortable audio level volume is achieved.

L.2 OFF / VOL / SQL: Knob OUTER The outer control is the squelch control. This is usually set to a position where undesired background noise is eliminated with no signal present. Rotate the squelch control clockwise to the point where the sound from the speaker is cut off. In this position, there will be no sound from the speaker until a signal is received. In order to hear weak signals, it may be necessary to rotate the squelch control anti-clockwise, allowing some background noise to be heard. NOTE: when using SSB for long-distance contacts, most operators turn the squelch control to the minimum setting.

M.1 RF GAIN / MIC GAIN: Knob INNER The RF Gain control is used to optimise reception in strong signal areas. Gain is reduced by anti-clockwise rotation of the control.

M.2 RF GAIN / MIC GAIN: Knob OUTER The MIC GAIN control is used to adjust, as required, microphone input sensitivity for optimum amount of modulation in transmit. The control should be rotated clockwise until the maximum voice volume is achieved without distortion. NOTE the Talkback function may be used to optimise the Mic Gain setting.

M.1 RF POWER / SWR CAL: Knob INNERThe RF POWER knob determines how much output power the radio emits. At the minimum (anti-clockwise) setting this will normally be 4w, when turned fully clockwise the radio will transmit at its maximum power.

M.2 RF POWER / SWR CAL: Knob OUTER The SWR CALibration control is used to calibrate the SWR meter in conjunction with SWR/CAL switch. See section B.1 above.

N. BAND: Knob Selects the band of frequencies to be used. Typically, each band has forty channels. Most multi-band CB radios will have from three to eight bands available.

O. MODE: Knob This knob switch selects CW, FM, AM, USB and LSB modes of operation. This selector changes the mode of operation of both transmitter and receiver simultaneously. Regular CB use in the UK uses FM, in the USA AM is used. FreeBand DX use is usually in Upper Side Band Mode.

P.1 CLARIFY - FINE: Knob INNER The CLARIFY control adjusts the radio operating frequency slightly. This function is used to fine-tune stations in SSB (Single Side Band / USB or LSB) Mode. The FINE adjustment will typically change frequency by about 1.5kHz up or down. When using SSB, even a few Hertz frequency difference between the transmitting station and the receiving station will distort the voice quite significantly. If the other station sounds like a cartoon character, then try adjusting the CLARIFY setting until the voice sounds normal.

P.2 CLARIFY - COARSE: Knob OUTER The CLARIFY control adjusts the radio operating frequency slightly. This function is used to fine-tune stations in SSB (Single Side Band / USB or LSB) Mode. The COARSE adjustment will typically change frequency by about 5kHz up or down. Some radios have a Clarify knob that effects only the Receive side of the radio, to enable you to fine-tune other stations. But being able to alter the transmit frequency as well may allow the radio to contact stations that are using "the Zero" (frequencies between the CB Channels, for example 27.400MHz). The SuperStar 3900 can be set by an engineer or repair workshop so that the Clarifier work on RX and TX. Other radios such as the Galaxy have a switch which allows the operator to select, RX, TX or Off.

Q.2 CHANNEL SELECTOR: Knob This knob is used to select Channels from 1 to 40 within the Band.

Q - What is SWR, how to check and adjust it

SWR or VSWR stands for "Standing Wave Ratio" or "Voltage Standing Wave Ratio" - both the same thing. All radios work at their best efficiency when the aerial is correctly matched to the frequency in use. The ideal aerial is exactly the same length as the wavelength of the signal, but certain fractions also work well and this is why you hear of a "Half-Wave", "Quarter-Wave" or a "five-eights" aerial. CB aerials need to be between thirty-five and thirty-six feet in length (depending on the CB Channel) for a "Full Wave", which is why a fraction is often used or a "loading coil" is added to the base (or even the centre).
The exact length of the aerial becomes very much more important when transmitting. If an aerial is not perfectly matched to the frequency in use, then a part of the "RF Energy" is reflected back from the aerial into the radio. If a lot of energy is reflected back it can seriously damage the radio. The way to avoid this damage is to tune the aerial to the band (frequency) in use or, if an aerial is being used for numerous Bands, an ATU or AMU (Antenna Tuning Unit, or Antenna Matching Unit) is employed. Tuning the aerial to the frequency in use is called commonly "Adjusting the SWR"

Checking SWR

The most common way of checking SWR is to use a SWR/Power meter (other ways include using an antenna analyser, or a DIP Meter). SWR meters typically come in two types (there are others, but these are the two most common):
- Single Needle SWR/Power Meter
  The simplest and cheapest SWR Meter there is. Some come with an additional switch which allows you to measure power output also (hence a SWR/Power Meter) but the one pictured above (left) is simply a SWR Meter. To use this type of meter the co-ax lead to the aerial is connected to one SO259 plug on the back (make sure it is the correct side) and a "Patch Lead" (a short length of co-ax with a PL259 plug on each end) is connected to the other SO259, and then on to the Radio. Set the switch on the SWR Meter to "FWD", then, on the radio, select the frequency to be tuned (for a forty-channel radio it would typically be Ch.20) then press and hold the PTT button on the microphone (first making sure there was nobody using that channel at the time). While holding the PTT rotate the knob on the meter until the needle points to the word "SET". Now, still holding the PTT button on the microphone, flick the SWR Meter switch to "REF" and the needle should drop to display the current SWR reading. If the needle does not drop, then the SWR is probably "off the scale".
- Cross-Needle SWR/Power Meter
  The cross-needle meter, while more expensive, is much simpler to operate and is less likely to give an incorrect reading by misoperation. It is connected between the radio and the aerial in exactly the same way as the simple meter, using a patch-lead. The RANGE switch is then set according to the expected Power of the radio (on the meter pictured above the three options are, "up to 20w", "20-200w", "200w to 2Kw"). If you have no idea of the Radio output power then try the highest setting first, then progressively lower. Once the RANGE is set, simply press the Microphone PTT and (hopefully) both needles will move. The Left-hand Needle shows the amount of power the Radio is sending to the aerial, and the Right-hand Needle shows the amount of Power being Reflected. Where the two needles cross is the SWR which is read from the Red scale.
Adjusting SWR

There are many different methods by which aerials are adjusted to correct the SWR mismatch. Possibly the most common, on base-loaded Mobile Aerials, is to alter the length of steel whip that protrudes from the loading coil. There is usually a small Allen-keyed lock-nut near the top of the loading coil. When this is loosened the Whip section can be moved up or down, thereby altering the overall length of the aerial. For a Mobile aerial the amount it needs to be moved is probably very little, in the order of a quarter or an eighth of an inch (3 to 6mm) at a time. Adjust the aerial a little, then use the meter again to see if the SWR has improved. Continue in that fashion until the best possible reading is obtained.

To determine whether the aerial needs to be lengthened or shortened, try checking the SWR on Ch.1 and on Ch.40. If the SWR is better on 40 than on 1, then the aerial needs to be lengthened, and vice versa. A LOWER Channel, or LOWER Frequency, has a LONGER Wavelength so needs a LONGER aerial.
A Few Facts
- SWR is usually quoted as "X:1", where X is the SWR reading. So you may have 1.2:1 (one point two to one) or, higher, 3:1 (three to one). A perfectly matched aerials would, in theory give the "Perfect SWR" of 1:1 but, in the Real World, there is nearly always going to be some flaw in the manufacture of the aerial, in the co-ax, or in the plugs. So, practically, 1.1:1 (one point one to one) is as good as it gets. Anyone that says they always SWR all their aerials to "One Point Zero to One" or "One to One" is either telling fibs, or has an inaccurate meter.
- Most SWR Meters are not precision instruments, especially not the cheaper ones. So do not be unduly upset if you cannot get a perfect SWR reading. It may be that the meter just is not capable of it. Likewise, if you try two separate meters, there is likely to be a difference in their readings. Most meters are sold to give a general idea of what the SWR is, and whether it needs adjusting.
- Any SWR of under 1.5:1 is generally acceptable. Managing to get to 1.2:1 is excellent and even a SWR of 2:1 isn't a major problem and is unlikely to cause major damage to the Radio. Do not lose sleep over the fact that your new Modulator Aerial will not SWR below 1.3:1, that's fine. Really!
- It is unwise to rely on any SWR Meter that is built-in to a CB Radio. The tiny meter is difficult to read and in-board SWR meters are notoriously unreliable. The main function that such a meter serves is to allow a quick check to see that everything is OK. If it suddenly changes where one day the SWR was OK, but the next day the in-board meters says it is off the scale, then it is time to check the aerial and the co-ax, and check the SWR with the better, external meter.

Q - How to make, or respond to, a CQ Call

Firstly, what is "CQ"? One irate DXer once said to me that it infuriates him to hear people say "Calling CQ", as (he said) "CQ" means "Calling", he was quite deflated to hear that it doesn't mean that at all. It isn't Rocket-Science, "CQ" simply means "Seek You", more clearly it means "searching for a Contact".

This section relates, mainly, to DX calling on the "Freeband" frequencies. Amateur radio has a slightly more formalised approach and an introduction to "best operating practice" is part of the licence training, although it is very similar to the way Freeband is used.

Obviously, many people develop their own CQ calls and styles. Some are amusing, some fine and some are frankly annoying.

Making a CQ Call

A basic CQ call on 27.555 might be something like:
- "CQ, CQ, CQ. Two Six Charlie Tango Zero Zero Zero calling CQ Eleven and standing by for any contact", or
- "CQ Eleven, CQ Eleven, Two Six See Tea Zero Zero Zero. CQ, CQ CQ", or very simply
- "CQ CQ CQ Two Six Charlie Tango Zero Zero Zero CQ CQ CQ"
The "Eleven" simply means the call is on the Eleven Metre Band. That convention is hang-over from the Ham practice where the call might be made on the twenty metre band, forty metre or whatever. It isn't really necessary on the "T5" (27.555 Mhz) as most Freeband is on Eleven metres (apart from Echo Charlie, and VHF Pirate frequencies, but that is a different story). Some people include the "Eleven", some don't.

The reason "CQ" is said over and over, and perhaps the whole call might be repeated, is to allow receiving stations to tune-in as SSB requires very accurate tuning.

If the T5 channel is very busy it can perhaps be difficult to hear replies to your CQ calls, so a slightly more useful call might be made on the T5, but asking for any response to be made on a different frequency. In this case the CQ call would include a "QSY" (change frequency):
- "Seek you, Seek you, Seek You. Two Six Charlie Tango Zero Zero Zero calling Seek you Eleven… Please Queue Ess Why to Twenty Seven Eight Five Five. Seek you, Seek you, Seek you", or
- "CQ Eleven, CQ Eleven, Two Six See Tea Zero Zero Zero. CQ, CQ CQ and QSY to Twenty Seven Five Eight Five", or very simply
- "CQ, CQ, CQ, 2 6 C T 0 0 0, Q S Y, 2 7 6 5 5"
Responding to someone else's CQ Call

The simplest response to a CQ call is to reply with your call-sign:
You hear something like, " CQ CQ CQ, One Six Fox Zulu Eight Four Two calling CQ" and you want to reply, so you might say, " One Six Fox Zulu Eight Four Two, this is Two Six Charlie Tango Zero Zero Zero", or even just "Two Six Charlie Tango Zero Zero Zero" but that's not quite so good as perhaps the calling station doesn't know if you're replying to him or to someone else.

Assuming you've replied to the Swedish FZ station (or a station has replied to your CQ on 27.555), you now need to vacate the calling frequency. So one station would say, "One Six Fox Zulu Eight Four Two, Q S Y to 27 point 5 8 5". You would then retune your radio to the new frequency, or perhaps confirm you've heard the QSY by saying something like, "Twenty Seven Five Eight Five. I go." and then retune.

Where you are replying to a CQ call that included a QSY, ("CQ Eleven, CQ Eleven, One Zero Eight Mike Charlie Five Nine Three. CQ, CQ CQ and QSY to Twenty Seven Five Seven Five") you do not reply on the T5 frequency, but instead retune straight away to 27.575 and, provided nobody else is talking on that frequency, you'd just state your call-sign, " Two Six C T 0 0 0", and see if the station hears you. Or, when you get to the alternate frequency, you might hear the calling station say something like, "One Zero Eight Mike Charlie Five Nine Three. Q S K ?". QSK in this context means "Who is calling me?", so again you'd just respond with your call-sign.
Joining a Conversation

The other way to initiate a contact might be to join an existing QSO (conversation) or speak to another station as they finish their last QSO. If trying to join an ongoing QSO, the polite way is to wait for a suitable pause in the chat, then call, "QSK", or "Break", or both, "Break Break QSK", then you wait to be invited in. The ongoing stations might say, "Break station go ahead" or something very similar. If you get no response to your first Break call, then by all means try again in case you weren't heard, but don't just keep shouting "QSK! QSK!", or ""Break! Dammit Break"" as it may be that the station has heard you, but doesn't want you to join his conversation.
If you've waited patiently, and heard a good DX station finish his QSO, then you might want to grab him before he moves off frequency, or goes back to the T5. As the QSO ends and the parties have said their "73s" or "Clear", you can call, "QSK Two Six Charlie Tango Zero Zero Zero" and hope the station picks up your call

One small point to note - in the USA, on Amateur Frequencies, the expression "Break-break" is supposed to mean, "Clear the frequency for priority/emergency traffic". So it is probably better to use "QSK" when it is a "Two Division" Station.
BAD Practices

This could be an endless list as people seem to be very imaginative in their ability to come up with Dumb Ideas for Things to Do on the T5... But to name just a few Classic Ways to show the World that you're a Muppet at Heart (or, for the Americans, to show you're a LID)...
- Talking on the Calling Channel / T5 - It is considered very rude and inconsiderate to hold your conversation on the calling Frequency (ANY calling frequency). Even if you can hear "No skip" and the Band is very quiet, it doesn't mean other stations can't hear DX either. It is really annoying if you've got a good contact "in the back of the box" that you're trying to hear, and some Muppet is loudly telling his mate what he is having for his tea. Having established a contact on the T5, ALWAYS QSY to another frequency.
- Whistling and Strange Noises - The amount of power a Sideband (SSB) signal uses is determined by the Modulation (amount of noise) that goes into the microphone. So some people whistle into their microphone to tune an amplifier, to match their aerial or just to power over most of the other signals on that frequency. It is unacceptable to do this on the T5 channel, and very rude to do it on a frequency that is in use even if you're waiting to "QSK" into the conversation. Other little games to maximise modulation include drawling, "Hoooooooola" or "Auuuuuuuuudio" into the microphone. Making animal noises into the mic doesn't even have the excuse of being useful for tuning an amplifier, so the infamous T5 Donkey and the other Zoo Residents are being done purely to annoy people.
- Funny CQ Calls - In Spanish speaking countries a common CQ call is, "Hola, Hola, Hola" instead of "CQ CQ CQ". "Hola" is simply the Spanish for "Hello". However, some (sadly, often British) stations have decided it is side-splitingly funny that "Hola" rhymes with "Cola", so we hear calls like, "Hola Hola Coca Cola", or the REALLY clever ones sometimes call "Hola, Hooooooooola, Pepsi Cooooooola".

Q - Can I use my radio in the car, whilst driving?

This section is relevant to current (2010) UK Law only.

Police Car

There is no law which specifically prevent use of your radio whilst driving.

The Law relating to Mobile Phone use specifically describes a "Mobile Telephone" as

" A device referred to in paragraphs (1)(b), (2)(b) and (3)(b) is a device, other than a two-way radio, which performs an interactive communication function by transmitting and receiving data."

The legislation goes on to say,

" two-way radio means any wireless telegraphy apparatus which is designed or adapted -

i. for the purpose of transmitting and receiving spoken messages; and

ii. to operate on any frequency other than 880 MHz to 915 MHz, 925 MHz to 960 MHz, 1710 MHz to 1785 MHz, 1805 MHz to 1880 MHz, 1900 MHz to 1980 MHz or 2110 MHz to 2170 MHz" (namely the mobile phone frequencies).

" (namely the mobile phone frequencies).
The specific legislation can be read at the following link: Police999 website link

The reason for this apparently generous exclusion of two-way radios from the legislation is quite simple: there was a huge ruckus from the taxi and mini cab businesses when the legislation was first proposed so exclusions were made to enable those drivers to use their radios. In addition a lot of Official drivers, including the Police, Ambulance, Coastguard, etc. also have need to use a radio whilst driving, so the exclusion also covers their activities.

BUT this does not mean you can thumb your nose at the Old Bill and wave your microphone at him as you blaze past!

All it means is that you cannot be specifically charged with "use of a communication device" if that device is a two-way radio. The Police can still decide to prosecute on the grounds of careless driving, dangerous driving, or driving without due consideration purely based on their opinion of your driving performance.

What it does mean is (for example):

you're stationary at a red traffic light and you say something on your in-car radio without realising there's a Police Car alongside
When the lights change, the gentlemen in blue immediately wave you to pull-over and happily inform you that they're issuing a fixed penalty charge for Mobile Phone use.
With, naturally, the accompanying Fine and points on your licence.
At this point you can, and should, POLITELY point out that it was not a Mobile Phone that you were using, but a "two-way radio".
Hopefully, they'll let it go at that point.

But, if you're in motion when the Police see you talking into the microphone and then they pull you over, there is a fair chance that instead of the Fixed-Penalty ticket for Mobile Phone use, they may decide that your driving warrants a charge of "Careless" or similar. So unless your driving was impeccable, and your vehicle totally faultless, there is a risk that you may get some kind of ticket anyway (and don't forget that even if your opinion is that your driving was flawless, it is your word against theirs).

The bottom line is that any communication whilst driving is probably not a good idea as it DOES reduce the amount of attention you're giving the road. So avoid it if you can. But if you do get stopped and challenged, the actual use of the Radio is not, itself, illegal.

Contrary to some opinions recently voiced on the CT ShoutBox, the legislation makes no reference to whether the radio in use is a CB or an Amateur radio (or PMR, or Taxi Radio or anything else), nor does the legislation differentiate as to whether the user is a Licenced Amateur Radio Operator or not.

Although not relevant to Radio, it is interesting to note that the Law referring to Mobile Phone use also includes:

i. sending or receiving oral or written messages;
ii. sending or receiving facsimile documents;
iii. sending or receiving still or moving images; and
iv. providing access to the internet;

So that covers most other types of phone use and the excuse "I wasn't talking Officer, I was Texting" is useless. But anyone Texting whilst driving in a moving vehicle deserves an instant Ban anyway.

Apparently the legislation also extends to use in a vehicle whilst stationary with the engine running. This is in order to make it illegal to use a Phone whilst at traffic lights or similar, but it does mean that if you need to use a "non-Hands-Free", stop and SWITCH OFF first.

Q - How do I Convert Channel Numbers to Frequencies?

In general, CB usage tends to be based on Channels, and FreeBand is based on Frequency. Therefore when listening to, or engaged in, a CB conversation you might hear, "We'll move to Channel 23", whereas on FreeBand, you're much more likely to hear, "We'll QSY to 27.585".

The reason is quite simple: the majority of CB radios have only a Channel display and do not include a frequency display. On the Freeband, many people use modified Amateur Radio "HF" or "10 metre" radios which do not have a channel read-out, only a frequency display.

But if you are using a Multi-Mode CB Set (such as a Tristar, Major, Stalker, 3900 etc.) it can be difficult to know where to go if someone suggests a "QSY to 27.455". The chart below converts Channel numbers to Frequencies and vice-versa. TIP: Don't forget to set the correct BAND though, as Channel 5 MIDS (27.015 Mhz) is quite different to Channel 5 High Band (27.465 Mhz), and Channel 5 on "Muppets" is way off (27.64125 Mhz)

CB Channel Numbers and Associated Frequencies

CB Channel Numbers and Associated Frequencies

Q - What is the Phonetic Alphabet?

The most widely used phonetic alphabet is the ICAO spelling alphabet, also called the NATO phonetic alphabet or the international radiotelephony spelling alphabet.

The purpose of the alphabet is to establish a common set of terms Worldwide so that groups of letters can be sent accurately over radio communication links regardless of the native language of the sender or recipient. The phonetic alphabet is typically used to ensure call-signs are transmitted accurately ("Two Six Charlie Tango Nine Zero Four"), and that names are received correctly (for example, an operator may say, "My name is Steve. I spell: Sierra Tango Echo Victor Echo")

There have historically been a number of such alphabets in use before the "NATO Standard" was generally adopted in the mid 1950, and some terms from the earlier alphabets do sometimes creep in to modern Radio Communications. For example, the Official NATO word for "B" is "Bravo", but you may often hear "Baker" used from the predecessor "Able, Baker, Charlie, Dog, Easy…" alphabet.

Many radio operators use names of cities or countries in place of the NATO keyword, but this can cause confusion. To hear a voice saying "One Eight Canada America Zero Four Two" might make you think it is a North America Station, rather than the Greek (18 Division) station it really is. Other people go even further adrift and make up some really strange Phonetic Abbreviations: Instead of Charlie Tango, you might hear "China Teapot", or "Christmas Toddy" but this defeats the object of the Common Alphabet that SHOULD ensure all people understand the letters being spent.

So do not be surprised if you hear a Station identify himself as: "Finland Rocket Easy Dingo Element Russia Ice-cream Coffee Kilo", just call him Fred.

Alpha	Hotel	Oscar	Victor
Bravo	India	Papa	Whiskey
Charlie	Juliet	Quebec	X-Ray
Delta	Kilo	Romeo	Yankee
Echo	Lima	Sierra	Zulu
Foxtrot	Mike	Tango
Golf	November	Uniform

Q - What co-ax should I use?

A large selection of 50 ohm coax cables are available and this is certainly not a comprehensive list, but a few general "rules of thumb" to follow:

Choose a coax with a minimum 95% Braid
Choose a coax made to a Military Specification (if applicable)
Generally solid core cables have a lower loss than stranded cables, but are less flexible.
Versions with an extra foil screen around the dielectric have improved shielding.
Basic (cheap) RG58 really is not suitable for transmission and really should only be used for broadcast reception. It should be avoided at all costs for any installation involving VHF or UHF TX.
The smaller cables, up to and including Mini8, should be good for around 350 to 400 Watts and the larger cables good for well over 1Kw. But, unless the location makes use of a small cable unavoidable, a thicker cable is always advised.

Some available cable types (Lengths relate to use on the 27Mhz/11m Band)

RG58/U - Solid centre conductor (use for fixed installations 15-20 metres maximum).
RG58A/U and C/U - Stranded centre conductor (ideal for mobile/portable installations and for patch cables) 15m metres maximum.
URM76 - Stranded "low loss" cable similar to RG58C/U
URM43 - Solid centre conductor with about 10% less loss than RG58 (not too flexible, so use for fixed installations 20 metres maximum)
Belden 9907 - High quality foil and braid shielded RG58 type coax with stranded centre conductor (quite flexible - use for fixed, mobile or portable installations) 15-20m maximum.
Mini 8 - Stranded centre conductor with a loss between URM43 and RG213. No applicable Military spec, so quality can vary (use for mobile, portable or fixed installations) 20-25 metres maximum.

NOTE: The "U" (e.g. RG58"U") merely indicates that the cable sheath is "UV Resistant" and should not be too badly degraded by exposaure to sunlight. i.e. it is suitable for outdoor use.

Low loss cables for longer HF runs and ALL VHF/UHF use as follows:

RG213/U - Stranded low-loss thick coax.
URM67 - Stranded low-loss thick coax.
Belden 9913 - Solid core low loss coax with foil and braid screen (9913F is more flexible but has a higher loss).
LMR400 - flexible and extra weatherproof.
WestFlex 103 - Air-spaced easy to use coaxial cable with half the loss of RG213/U and URM67.
Ecoflex 10 - Stranded foil and braid screen low loss cable, suitable for UHF applications.
RG214/U - very high quality with Silvered Copper stranded core and double Double Silvered Copper Braid screen.
H100 - Solid core with foil and braid screen low loss coax.

Unfortunately there's a lot of cheap cable out there (particularly the RG58 types) and it certainly pays to buy a known make like Belden and from a reputable supplier.

Co-ax cable is one of those items that, generally, you get what you pay for. It is rarely a mistake to "upgrade" to a better (usually more expensive) cable.

Signal loss from the coax increases as the frequency gets higher and, with the 11m band being near to the top of the HF Radio spectrum, it's certainly worthwhile considering low loss cable for runs over 15 metres.

Low-loss cables really are a must for all For VHF and UHF applications (particularly UHF).

CABLE LOSSES

The following table has been created using the information available on the Maplin Website and is intended merely to show COMPARATIVE Loss figures for their range of Co-ax Cable. It has been pointed out that the figures for 100MHz are significantly above the losses that would be occur at 27MHz, and that the losses at 1000MHz are of little practical interest for anyone using CB, Freeband or Foundation-Licence Frequencies - only the Amateur 23cm band and above has that high a frequency. But these figures do allow a comparison of (Maplin's) cable types.

A table showing cable losses for other frequencies can be found HERE

Put Simply

A "3 dB Loss" is half the signal. So a radio with 100w output, going through ten metres of cable that has a loss of "3dB per 10m" will only deliver 50w at the far end. The rest will have been "lost" as heat in the cable
A "9 dB Loss" is seven eights (87.5%) of the signal. So a radio with 50w output, going through thirty metres of cable that has a loss of "3dB per 10m" will only deliver 12.5w at the far end. The rest will have been "lost" as heat in the cable
Very approximately: 3dB is half, 6dB is a quarter, 9dB is one eighth, 10dB is one tenth.

It is also worth noting that Maplin is notoriously expensive as a source of "good" cable. Companies like Westlake (LINK) sell RG213 for £1.20 per metre (+P&P).

Another cable to be considered, although slightly more expensive, is Westflex Airspaced co-ax. This has approximately half the loss of RG213u and URM67. The price from Westlake (see above) is £1.50 per metre (+P&P).

Coax	Maplins own Description	Cable Width (Outer)	Maplins Price (per/m)	Loss at 100MHz per 10m length	Loss at 1000MHz per 10m length
RG213	"A high quality coaxial cable to MIL-C-17"	10.3 mm	£6.04	0.68	2.52
URM67	"A high quality, heavy duty, RF coaxial cable ideal as a transmitter up-lead. Stranded core, 7/0. 77mm copper conductor with solid polythene insulation, braided screen and sheathed in black PVC"	10.3 mm	£6.04	0.63	2.33
RG58	"A screened RF cable having a stranded core 17/0.19mm tinned copper conductor with a solid polyethylene insulator and a braided copper screen"	5 mm	£1.14	2.00	7.60
URM76	"A high quality screened cable for high performance audio connections. Stranded core, 7/0.32mm plain copper conductor with polythene insulation, braided screen and sheathed overall in black PVC"	5 mm	£1.24	2.00	7.60
RG174A/U	"A high quality coaxial cable to MIL-C-17, designed for use with SMA, SMB, SMC and MCX connectors" *	2.8 mm	£1.24	2.62	9.29

* - It is interesting to note that the "Mini" RG174 is quoted as having the same "Military Specification" ("MIL-C-17") as the low-loss RG213. This does go to show that "Mil Spec" does NOT mean "Low Loss" and should never be assumed to have that meaning. "Mil Spec" or "MIL-C-17" simply refers to the manufacturing quality standard.

Satellite Cable

Finally, there has recently been some discussion on the CT ShoutBox about using "Top Quality", "really thick low-loss" satellite dish cable for radio installations. This is not recommended. Sky, or other, satellite dish cable may LOOK very similar to good quality CB/HF/VHF Co-ax, but it is usually 75 Ohm cable. CB and Ham radios require a 50 Ohm aerial connection so using 75 Ohm cable instantly causes a significant mismatch on the aerial system.

Q - What Codes and Common Expressions are used?

The use of "Secret Codes" is specifically proscribed in the UK Amateur Radio Licence, but there are some codes that, being far from "secret", are permitted. As CB has no licence, and FreeBanding is illegal anyway, there are actually no limitations on what can be said on those bands but, generally, only commonly accepted Codes and Abbreviations are used

The Ten-Codes

In the early days of CB in the UK, the American "10 Codes" were regularly used (inspired perhaps by C W McColl's single "Convoy" or the later Kris Kristofferson film of the same name). Some limited usage of the Ten-Codes remains on the UKFM CB bands, but their use is considered rather "Muppet" on the FreeBand and is distinctly frowned upon on any Amateur Radio Band. The very limited number of 10-Codes you might still hear on CB or Freeband include:

CODE	MEANING	USAGE
10-1	Receiving Poorly	"You are 10-1 to me", or "That's a right 10-1 station. Terrible signal"
10-4	Message received	"10 4, I've got that" (But please avoid the terrible Hollywood "That's a Big Ten Four Good Buddy", it's Pure Muppet now.
10-7	Out of Service	"I'm going 10-7 now while I change aerials", or "His station has gone 10-7 since he moved home"
10-9	Repeat Message	"10 9 on your last", or more commonly, "give me a Nine on that?"< /td>
10-10	Transmission Complete	"10 10 I'm gone", or one of the old Goodbye Jingles, "Ten Ten 'til we do it again. We down. We gone. Bye bye"
10-20	Location	"My 20 is Town-name", or "What's your twenty?"
10-100	Bathroom Break	"I gotta go 10-100, be right back"

Mostly for Amusement, a LIST OF ABOUT 60 TEN-CODES CAN BE DOWNLOADED HERE (Click)

The Q-Codes

The Q-Codes were originally developed for use by Morse operators as it was a lot faster and easier to transmit and receive a three digit Code than a full sentence. A typical example might be "QSY" which can be transmitted much faster than "Please change frequency to…". A number of Q-Codes have been adopted into Voice Communication within both Amateur Radio usage and Freeband (but are rarely heard on FM or AM CB).

However, a number of Q-Codes are regularly heard on Voice. These include:

CODE	MEANING	USAGE
QRM	Interference - Man-made or Intentional	"I'm getting a lot of QRM from my Laptop"
QRN	Interference - Natural	"We will have to cut the 'Net' short tonight, I have a lot of QRN from the Thunderstorms"
QRZ	Who is calling me?	Having changed frequency after calling CQ on the calling channel, "26CT000 QRZ?"
QSK	Seeking Access, Break	When asking to join an established conversation or QSO, "Break, QSK QSK 26CT000?"
QSL	Have you received my Message? Or, Your Message received	Typically QSL Card are exchanged by two stations after a Contact to provide evidence and greetings of their QSO. It has more recently become bastardised to mean "OK?", "Did you get that?" or, worse, "Innit?"
QSO	A Contact	"I was in QSO with 108CT000 last night", or "The skip was excellent, I managed two QSOs to 43 Division"
QSY	Change Frequency	"CQ CQ CQ 26CT000 calling CQ, QSY 27 point 585", or "we seem to have another station on this frequency now, shall we QSY to 27 point 585?"
QTH	Station Location	"My QTH is just north of the High Street in Town-name"

The original list of Q-Codes ran to possibly 400+ Codes, 99% of which are irrelevant or not in use on Voice Bands but, if you wish to read them for amusement,
A PDF FLE OF ALL Q-CODES IS AVAILABLE HERE (Click)
(I was particularly amused to read the unofficial code "QLF".
This would describe a poor Morse operator whose code sounded as if he was operating the Morse Key with his "LF", Left Foot).

Do please bear in mind that the Q-Codes are only really intended for use by CW operators to shorten the messages that have to be keyed, although a few have become generally accepted for use in Voice Telephony (those listed above). BUT, excessive use of Q-Code in voice contacts is a sure-fire way of labeling yourself as a "LID" or a "Muppet".

Similarly, it is often considered pretty silly by many people to actually say, "Hi hi" (or, even worse, "Aitch-eye, Aitch-Eye") to indicate laughter in a voice contact, why not just laugh? After all, you wouldn't actually say, "LOL" when speaking to someone . . . . would you? (But maybe you would!.. Hi Hi!)

The convention of "hi hi" is again a CW (Morse) thing as the code ("H"= "....", "I" = " ..") is considered to sound like laughter when keyed: " .... .. .... .."

Q - How do I wire a microphone to my CB?

The majority of CB sets have a four-pin microphone socket. Some CB sets may have more as their microphones are fitted with Up and Down buttons or other features, but the same four basic functions will probably be included within the pins.

The four standard Pins are:

1. Earth - Common - Braid
2. PTT - TX - Transmit
3. RX - Receive
4. Mic Audio - Mic Ground

To wire a new or replacement plug onto a microphone for CB use, simply identify the correct pin for each wire using the chart below, then carefully solder the wires to the plug.

If you do not know which wire is which, and your microphone is not one of those listed on the Chart, there is a fairly simple method which should identify at least the main wires:

You will need a Multi-meter, or a Circuit Tester, or a Continuity Tester, or some other way of identifying whether there is a circuit present - even a torch bulb, battery and two wires would do...

1. Attach one end of the Tester to the Braid wire of the microphone. This is the Earth.

2. Press the PTT Button on the microphone and identify which other wire makes a circuit with the braid. Release the PTT to check the circuit breaks. When you have identified the wire that only makes a circuit when the PTT Button is pressed, this is the "PTT / TX - Transmit" Wire.

3. Keeping one end of the Tester on the braid, check the remaining two wires. One wire should only make a circuit when the PTT is NOT pressed, and the circuit should break when the PTT is pressed. When identified, this the the "RX - Receive" wire.

4. If you only have four wires from the microphone, you've identified the Braid (which will be the Earth/Common), you've identified the PTT/TX, and the RX, so the remaining wire is the Mic Audio.

If the mic has additional wires, it MAY be possible to identify those that control the Channel Up/Down by the same means: place one end of the Tester on the Braid, and see which wire makes a circuit when the UP or Down button is pressed - etc. This will not work for all microphones as some use a resistance circuit or similar, but if you have no idea which wire does what, it is worth a try.

Click on the small image below to open a PDF Chart showing Mic Wiring Pins
for common CB Sets, and some common microphones.

Q - What do the Call-signs and Division Numbers mean?

A Call-sign is simply an unique identifier for any Radio Station. All Radio Stations have them in one form or another: Even "95.8 CapitalFM" is, in a way, a Call-sign as it lets you know which station your radio is receiving.

CB users use a "handle" in place of a call-sign, but it serves the same purpose - it lets people listening know who is speaking. CB Handles are sometimes far from being "unique" identifiers though: how many "Super-Stud"s are there I wonder; or how many plumbers with CB radios that think "Pipe-Bender" is original?

Amateur Radio Stations, Worldwide, have a unique call-sign which is assigned by the issuing authority. In the UK at the moment a newly qualified Foundation Licence holder would be something like: "M6ABC" (see the FAQ about Amateur Licences for more details). The "M" means UK, the "6" means a Foundation Licence and the "ABC" identifies the individual.

FreeBand Call-signs are slightly different. They comprise three groups of digits in the format: NNAANNN (one/two/three numbers, two letters, three/four numbers). An example would be 26CT001. The numbers in the front, before the letters, are the Country Code or the "Division Number" - in this example the numbers are "26". England is 26-Division, so we know it is an English Station. The two Letters usually mean a Club or Affiliation so, in this case, it is CT for Charlie Tango, and the last digits are the member's number within that club. So, another example, 26CT100 is a Charlie Tango Station, in England, and the operator's number is 100. Go to the MemberList pages on Charlie Tango and you'll see that is Lee / Firetrap's call-sign. A different example might be 9CT002: "9" Division is Canada, CT again and 002. So that is the call-sign for Pete / Zort in Ontario.

The only big drawback of the FreeBand Call-sign system is that it is not centrally managed or policed in any way so there could, in theory, be many people calling themselves 26CT100. There is also no requirement for FreeBand stations to be registered with any group, so anyone can just make-up a call-sign for themselves and it is perfectly valid. Michael Norris of Swansea, born on the 22nd of Arpil, might decide to call himeself 163MN224 (163 Division is Wales) - Or, as there really are no Rules, he could decide to call himself XYZ-407-BP-4 if he wanted to!

To facilitate working out what call-signs mean, there are two Chart you can download in PDF format. One Chart has a list of Countries and the appropriate Division Number (Country Number) and the other Chart has a list of the Division Numbers and the Country to which each applies. So, using the Chart, you could work out that the station you hear on your radio calling himself 116-Mike-Alpha-124 should be in Turkey, or you might be very pleased to have made a Contact with a "121 Division" Station when you work out that it is in The Bahamas.

CLICK HERE
for
Country-to-Division-Number
Chart

CLICK HERE
for
Division-Number-to-Country
Chart

Also see the section "How do I get an Amateur / Ham Licence?" (( LINK )) which lists Amateur / 'Ham' Call-signs

Q - How do I get an Amateur / "Ham" Licence?

The following information relates to the United Kingdom (UK ONLY)

Amateur Radio Licenses in the UK are controlled by OFCOM and are obtained by passing the relevant RSGB (Radio Society of Great Britain) tests and examinations.

At this time there are three levels of radio licence: the FOUNDATION, the INTERMEDIATE, and the FULL and the tests for each level must be completed before the next level can be attempted. As the Foundation and the Intermediate levels both include some practical assessments they must be undertaken with some form of training or supervision, the Full licence requires only completion of the written examination and can be self-taught.

There are generally no limitation on the Modes available to Amateur Radio operators at any level and Foundation, Intermediate and Full Licence holders can use AM, FM, SSB, CW or Digital Modes such as PSK31 or SSTV. Foundation licenses are limited to HF, plus 2m and 70cm and may not use FSTV, but Intermediate and Full licenses have access to the full amateur radio spectrum.

Each of the three RSGB written examinations comprise multiple choice questions. They must take place in a Registered Location under the Supervision of RSGB Registered Examiners. There is a fee payable for each examination (and again payable if failed and reattempted).

Contrary to popular belief, there is NO requirement for a CW / Morse Test in the UK licenses any more and previous "Class A" and "Class B" licence holders now enjoy exactly the same privileges.

Foundation Licence Training.

The Foundation is the entry level amateur radio licence and requires basic knowledge of radios, transmitting and operation, and understanding simple electronics and circuits.

Although set at a basic introduction level it does require some learning, understanding and remembering fact and figures in order to pass the written exam. It also requires completion of a number of practical assessments: such as making a VHF contact; making a HF contact; SWRing an aerial; and an "Appreciation of Morse" before the written test can be taken. For this reason it is usually necessary to undertake a training course or session at an Amateur Radio Club or other organisation. Some clubs run the Foundation training on one evening per week, over the course of about six weeks with the written test on the final evening. Other places may offer "Intensive Courses" over one or two weekends.

The Appreciation of Morse Practical session is not a test. There is no requirement to send or receive any specific number of Words Per Minute, it is simply to ensure that the Student understands what Morse is, and can send and receive signals in a test environment. The send and receive can be repeated as often as necessary, and taken as slowly as necessary, and the student has a written Morse sheet in front of them at all times.

A lot of the old-school "City and Guilds" Amateur Radio Operators now claim that Foundation licenses are "given away on Cornflakes packets". While the level of the Foundation Training is indeed Basic, it is not a walk-over and does take some concentration and study in order to pass. Anyone walking into the examination with no prior study and under impression "I've had a CB for twenty years, what do I need to learn?" is likely to fail.

The RSGB publish a book, "Foundation Licence Now" which covers the entire syllabus. If the book has been read and understood, an the salient points remembered, then the written exam will be passed with ease.

Intermediate Licence Training

At the Intermediate level there is significantly more detail involved, an understanding of electronic components is required and a much higher level of practical assessments must be completed before the written examination can be attempted.

Amongst the practical assessments required for the Intermediate licence is a requirement to build an appropriate electronic "Project" either from published plans or from a commercial kit, so an understanding of components and circuit diagrams is vital, as are some soldering skills. Typically the project might involve building something like an 80m HF Receiver, or a Notch Filter, or a SWR Meter and Matcher perhaps. It is important to check with the Trainer that whatever Project is planned is appropriate and complex enough to qualify as the Passed Assessment. For example, building a simple SWR Meter would be considered too basic. Other elements of the practical assessments involve building a simple circuit to test various components and tuning a VFO.

As with the Foundation Level training, some ARC clubs offer Intermediate Training over a period of perhaps ten or thirteen weeks, or possibly over a period of three or four weekends. Again as for the Foundation Level, there is an RSGB Book "Intermediate - Building on the Foundation" that contains all the information required to pass the written test, plus details of the practical elements that need to be completed.

The Full Licence

The full licence is the highest level of Amateur Radio Licence available in the UK. It involves no practical work, but a very much higher level of knowledge and understanding of electronics, radios, radio theory and aerial theory is required before sitting the written examination.

The Full Licence gives the same privileges as the preceding "City and Guilds" examination and provides the Radio Operator with a significant amount of freedom (and therefore also responsibility) in terms of equipment that can be used, the amount of power that is available. Full licence holders are also permitted to operate radio equipment outside the UK.

There are less Training opportunities available at the Full Licence level and a significant proportion of students prepare by home-study, perhaps with Revision Sessions organised by Clubs and Organisations. But some ARC do offer the full Advanced Training Course.

As for the other two levels, there is an RSGB Book available "Advance, the Full Licence" which contains all that is needed to successfully pass the written examination.

LICENCE	Max. Power	General Limitations
FOUNDATION	10w	HF (160m to 10m), VHF (2m) and UHF (70cm) Commercially made equipment only UK Only
INTERMEDIATE	50w	All UK Amateur Frequencies Can build / Repair equipment from kits or published plans UK Only
FULL	400w	All UK Amateur Frequencies Can build / Repair equipment from scratch Can operate abroad where reciprocal agreements exist Can operate Maritime Mobile with permission of the Ship's Master.

At first, Amateur Radio Station Call-signs appear to comprise a semi-random collection of letters and numbers, but there is some logic involved (although they're not as simple to understand as the generally accepted and used FreeBand call-signs). The first letter (nearly always) identifies the country in which the licence was issued, and the remaining letters and numbers identify the individual that holds the licence, and perhaps some information about the level of licence held.

LICENCE	Current Typical Format	Meaning / Historical	Examples
FOUNDATION	M6abc	"M" indicates a UK Licence, "6" indicates the licence is Foundation level "abc" are the individual's unique identification letters Previous to "M6" Licenses, Foundation holders were issued "M3". There is no difference in the two, the change to M6 was simply made because the majority of M3 call-signs had been used.	M6MAD, M6ERG, M3CDE, MD4CAT
INTERMEDIATE	2x0abc	"2x0" indicates a UK Intermediate Licence), "x" is the Regional Identifier (see below) "abc" are the individual's unique identification letters	2E0QWE, 2W0DAI, 2M0MCC
FULL	M0abc	"M" indicates a UK Licence, "0" indicates the licence is Full level "abc" are the individual's unique identification letters Previous to "M0" Licenses, all UK Class 1 and Class 2 Licenses were prefixed "G". Before the Morse requirement was lifted the last digit usually indicated a Class 1 or Class 2 licence determining whether the licence holder had completed the mandatory Morse Speed Test and could use HF frequencies, or was limited to VHF and above. Now all "G" licenses and "M0" have exactly the same privileges.	M0SDY, M0DAN, MI0MIL

A Summary of UK Callsigns follows:

Call sign	Issue dates and details
G2 + 2 letters	1920 - 1939
G3 + 2 letters	1937 - 1938
G4 + 2 letters	1938 - 1939
G5 + 2 letters	1921 - 1939
G6 + 2 letters	1921 - 1939
G8 + 2 letters	1936 - 1937
G1 + 3 letters	1983 - 1988 - originally issued as Class B licence
G2 + 3 letters	Originally issued as "Artificial Aerial" licence
G2 + 3 letters	Originally issued as "Artificial Aerial" licence
G3 + 3 letters	Issued between 1946 and 1971. Originally issued to amateur radio Class A licence holders
G4 + 3 letters	Issued between 1971 and 1985. Originally issued to amateur radio class A licence holders.
G5 + 3 letters	Originally issued to foreign nationals as a form of reciprocal ham radio licence. They were withdrawn and either they used existing home calls with additional UK prefix / callsign, or if applicable they could apply for UK licence.
G6 + 3 letters	1981 - 1983. Originally issued as a class B licence
G7 + 3 letters	1989 - 1996. Originally issued as a class B licence
G8 + 3 letters	1964 - 1981. Originally issued as a class B licence
G0 + 3 letters	1986 - 1996. Originally issued as a class A licence
M1 + 3 letters	1996 - . Originally issued as a class B licence.
M0 + 3 letters	1996 - . Originally issued as a class A licence
M3 + 3 letters	Foundation licence.
M6 + 3 letters	Foundation licence, from May 2008.

UK Amateur Licenses also include a Mandatory Prefix and an optional (but recommended Best Practice) Suffix when used.

PREFIX	SUFFIX
PURPOSE: - The Prefix Letter indicates from which Country within the United Kingdom the Radio is currently being operated. If no Prefix is shown it is assumed to be operating in the Default Country, England. However, for Intermediate licenses (only) the "E" is required (eg 2E0MLN).	MEANING: - Inclusion of the Suffix letters used to be Mandatory but is now optional (although R ecommended). The letter(s) indicate the type of location from which the station is transmitting.
POSSIBLE PREFIX LETTERS: W - Wales M - Scotland I - Northern Ireland D - Isle of Man J - Jersey G - Guernsey E - England (Intermediate only)	POSSIBLE SUFFIX LETTERS: No Suffix - The Station is being operated from the Registered Address of the Licence Holder. /M - Mobile. On foot, Car/Van/Truck or aboard a boat on an inland waterway. /A - Alternate. A UK Address other than the register station. /P - Portable. Operating from a location that does not have a Postcode (eg, Hilltop or Field). /MM - Maritime Mobile (Full Licence only)
PREFIX EXAMPLES: MW6DSA - MW=Wales/6=Foundation - Foundation Licence in Wales MM3TYU - MM=Scotland/3=Foundation - Foundation Licence in Scotland M0POP - No regional identifier, default is England - Full Licence in England 2D0CAT - "D" identifier=Isle of Man/2x0=Intermediate. MG6TOM - Foundation Licence in Guernsey 2E0CCT - Intermediate Licence in England. (the "E" only shows in the Intermediate Licence)	SUFFIX EXAMPLES: M6NBV/M - Foundation Licence, in England, currently Mobile MM0WEB - No Suffix, Default is at Registered Address, Full Licence at Home in Scotland 2J0RUT/A - Intermediate Licence Currently at Alternative Address in Jersey MW3TRS/P - Foundation Station operating "Portable" in Wales M0TMP/MM - UK Full licence operating from a Ship or Boat on Tidal waters.

Q - How would I operate a Portable Station?
Operating Portable - A few Tips

A number of Radio Operators chose to spend some of their time "Operating Portable" and the following Tips were produced by one such Charlie Tango station with a fair amount of experience at the pastime. As he explained, a few simple tips might change a day-out from a Pain to a Pleasure.

The FAQ Section on Ham Licenses and Call signs explains what operating "Portable" means, but in summary it is the practice of taking a radio to a hill-top or other outside location rather than operating from the car (Mobile) or indoor (Base or Alternate).

Why?

Usually Height!

Even if you live in a 'good' location for radio very few of us are fortunate to live on top of tall hills or mountains. At home you may have restrictions on aerials, you may have 'inquisitive' neighbours or you may simply have no desire to set up a fixed base station. The ever constant worry of causing TVI (even at low power levels) can take away a lot of enjoyment.

Generally, you can get away with murder in Britain these days, but put a couple of lines over the TV when the neighbours are watching their Soaps and you will be hung!

Other reasons for escaping to wide-open spaces with your radio might include: getting away from QRM interference from neighbours; heavy traffic noise at home; nowhere to set-up in the house; or (let's admit it) sometimes just to get some peace and quiet from the Spouse and Children while you're enjoying your hobby.

A decent view and fresh air can't be bad either.
Location:

So where are you going to go?

A big hill helps! Obviously the higher you are, the wider the horizon so the greater range you're going to get. But if there are no hills anywhere near you, then even an open, clear area at relative low altitude can be fine.

After seeking height, the main thing to look for is an area away from 'population', primarily to avoid as much QRM 'noise' as possible. If you're near the sea, perhaps try a quiet location on the coast so you have a good 'launch' for your signal over the water.

Take care about Private Land. It is not always clear where Public Right of Way exists, and there are places where you're permitted to walk through, but they may object to you setting-up a radio station there, albeit a temporary one.

It's not always easy, but it is often worth travelling the extra mile for that 'perfect' location.
Homework:

Even if you have lived in the same area for ever, it's still worth getting a good local map of to search for potential locations. Once you have identified a few possible spots, then spend a little time 'visiting'. What looks good on paper is not always what it seems.
General Public:

Joe Public may well turn out to be your biggest problem as, in the modern world in which we live, it's difficult to find a location devoid of people. You park up in the middle of nowhere and within moments it seems, somebody walks by!

The chances are that you've decided on a day of Operating Portable because the weather is good, so that will bring other people out . . . and because you think it's a great view, others will too. They will also bring their 'electrical noise': the games and electrical gadgets to keep the kids entertained, or they'll sit in the car with the engine running and a nice loud crackle of ignition QRM will cover the area.

And, no matter how spectacular the view, your antenna will be the point of interest! "Whatcher doin' Mister?", "Wassat then?" or, if you're wildly unlucky, "Ah, you're a Ham Operator… When I was in the Navy……."

If you are approached try to be friendly and informative to any questions that may get asked.
Equipment and power requirements:

Whatever your radio interests you still need to transport it! I tend carry equipment in plastic tubs. One for protection and secondly you can put a 'kit' together with ALL the various power leads, patch leads, spare fuses etc. Travelling to a great spot, getting half-way set-up and then finding you have forgotten to pick up a simple lead is very annoying!
- Carry a small tool kit. It does not have to be anything fancy but it could save the day. A couple of small screwdrivers (cross-head and flat), pliers, wire cutters, a hobby-knife and some tape may go a long way to rescuing a dead-radio set-up. If you are travelling a distance for a day-long bash, then taking a second radio is worth a consideration. You might never need it but......................
- An antenna for the Portable Station can simply be a low-cost base station one. I use a Silver Rod type because they 'telescope' down to a realistic length for transportation, they are light and cheap. I set mine up at home for SWR and the spray paint over the joins of the various sections. Once up the hill I simply pull out the antenna to the paint marks and tighten. Job done.
- You are, however, going to need some sort of mount for the antenna. I use a home made drive-on base (made from an old axle-stand and off-cuts from an old bed frame). Drive-on bases can be bought from Ebay, or a number of Radio Merchants (Moonraker probably currently offer the cheapest at £19.95). Remember to allow room in the car for it!
  
  My axle-stand mount takes a two-inch pole which is about four feet long (again, suitable to fit in the car for transportation) and this puts the antenna just above the roof of my car. Some may say that this too low, but I can put it up by myself, it requires no guy lines and it is fine in even a moderate breeze. Remember that the chances are you're on a hill-top, so at 1500 feet ASL the antenna is probably high enough, and an extra ten feet would be irrelevant.
  
  Another idea is to strap the antenna to a fence post or a gate. If you're using a fence post, make sure that your aerial isn't going to pull the post over, or break it, and use guy-lines if necessary. If you mount a guyed-antenna on a gate-post adjacent to a gate that's in use remember there may be a risk of people tripping over the lines. Likewise if your guy-lines cross a footpath a little bit of consideration is required.
- Bigger and more complicated antenna systems may work more efficiently, but they usually require more space, more people to set-up and they tend to be noticed a lot more. If you are operating on 11m Sideband do remember that you do not really want to attract the attention of the authorities, so maintaining a low-profile is always a better idea.
- I do carry a second FULLY CHARGED battery and jump leads. Remember if you are running high-power equipment some can be very heavy on current if run on max! I also tend to start the car if an interesting contact is made to keep the battery topped-up. Taking a portable generator may be, on the face of it, a good idea but good ones can be both expensive and bulky and even a small generator will make noise which may attract unwanted attention. Then you have to remember to carry spare fuel which can add to the list and the load. One other power issue, do remember to take a spare battery for your power mic (if it uses one) if your Astatic Mod 575/M6 is ever going to need that new battery, it'll be when you're miles from the nearest shop.
  
  One final thought about power, don't use the last drop of juice in your batteries for that wonderful contact with the chaps in California, and then find you can't start the car to get home. If you're driving a car with a manual gearbox, it is actually worth trying to park facing downhill so, if the worst happens, you can roll it downhill for a bump-start.
- Don't forget to take the basic bits and pieces: a note pad or two; a pen (and a couple of spares); your DX Guide or other documents (frequency lists, Q-Codes, Division Codes, etc.). Taking a personal computer and mobile internet connection is nice for 'cluster' info for that serious session, or to keep an eye on the Charlie Tango ShoutBox during a CT Net.
- A pair of headphones is worth the investment. From your point of view it makes listening for weak/quiet stations a whole lot easier and it is just amazing how far the audio can travel from your speaker when outside!
Personal requirements:

You've taken care of the Radio's needs, but don't forget yourself! Take plenty to eat and drink. Don't get dehydrated as that may affect concentration and things will get damaged or accidents can happen. Remember that you're supposed to be having a good time so make life as comfortable as you can.

Even on a Summer day hill-tops can be breezy. Take a few more layers and a hat. You can always take them off.

It is also a good idea to take along a basic First Aid Kit and a blanket, just in case the worst happens, and you should also always let someone know where you're going and what time you're expecting to return, or maybe even take a mate along - just in case!
Idiot Sheet:

Make a 'check list' of ALL the equipment you plan to take with you: kit; tools; spares; documents; etc. It may seem a bit OTT perhaps, but it saves on stress on the day and means you can usually get on your way quicker and with less drama. It will be something minor that could ruin your planned outing.
Have fun!:

It it completely pointless doing all this if it's a chore. Get out and have a good time on the air!

No rocket science involved .. .. I know.

Q - Common CB and Radio Terms

CB Radio	CB, CB Set, Rig, Chicken Box
Aerial (English) Antenna (American)	Twig, Beam (Directional), Vertical, Colinear, Dipole, Nine-up-nine-down, Base-loaded, Centre-load, Base / Mobile / Rubber Duck Also associated: Mag Mount, Gutter Mount, Mirror Mount, Trunk Mount,
27.555 MHz	Internationally recognised 11m SSB (Pirate) calling Channel T5, Triple 5, 555, Triple-Nickel, High Channel 12, Channel 52
UK FM CB Band	UK Block, UKFM, UK40, 27/81, CB27/81, Muppets, Muppets Band
European FM CB Band	EU Band, CEPT Band, Mid Band, EU Block, CEPT Block, Mid Block, Mids, Euro, FCC, American Band NOTE: - the American legal 40 channel "FCC Block" uses identical freqencies to the European Channels, except that in America the Mode is AM and in Europe (inlcuding UK) the Mode is, typically, FM There are AM and SSB operations allowed in Mainland Europe now, but they are still currently illegal in the UK.
Linear Amplifier (TX Power booster)	Linear, Boots, Burner, Heater, Heat, Helper, Footwarmer, Linner, Kicker Increasing power may be referred to as: Throwing on some coal (on the fire), turning up the wick, going QRO, getting some help, putting the Boots on, etc. Antonym: "Barefoot", "Going barefoot", "Running barefoot" - Operating on the Radio's Power only.
Superbowl / Superbowler	"The Superbowl" is an American sub-set of CB users who run ENORMOUS power (thousands of watts) in "Brute Force" Keydown Contests. They have a distinct way of speaking and their own jargon and can frequently be heard in Europe on FCC/Mid Ch.6 channel 6 / 27.025 MHz AM Mode
Echo Charlie	Other Pirate (i.e. non legal) bands used by radio operators in a similar manner to the 11m frequencies outside the legal band The original "Echo Charlie" band was/is on 45m (6.53 to 6.70 MHz LSB) although other EC Bands exist. Unlike 11m, some EC frequencies are in use for official purposes (including some Air Traffic and Rescue Services), so significant care should be exercised before transmitting there. EC Bands are not legal and may be more heavily monitored or policed than the Freeband 11m Channels
SWL	Short Wave Listener. Someone who listens to the Amateur Radio Bands but does not transmit. No licence is required and listening to the Amateur Frequency Band is completely legal. Some SWLers may be licenced Amateur Radio Operators who have simply elected not to Transmit any more.
Propagation	Skip, Conditions, Prop, "E-Layer", "F-Layer", Band is Open (or Closed) Special atmospheric conditions which will reflect radio waves (in a specific Band) thereby permitting long-range "DX" Contacts.;
Shack	Radio Station or Room. Traditionally, "Ham" Radio operators were usually housed in a wooden shed at the foot of the garden, hence in "the Shack"
Working Conditions	Radio Equipment. E.g. "My working conditions are: Yaesu FTDX9000 with a Heil Boom Mic, Running 200 watts, through a Bazooka aerial."
WX	Weather Conditions. "What's the WX there today?".
Radio Report	A report from the receiving station to the sender telling them the quality and strength of their transmission. Quality is from ONE (Unable to understand you) to FIVE (perfectly clear and understandable) and Signal strength is from ONE (Weak Signal) to NINE (very Strong Signal). Thus "Five and Nine" is an excellent, clear signal "Plus Ten", "Plus Twenty Dee Bee" means that the receiving station's S-Meter is going over Nine into the +10 or +20. An Extremely strong signal.

Q - What Power Supply should I get?

There are two main types of Power Supply available, and many variations in Amperage and Voltage. This section BRIEFLY explains the differences between the types and how to judge what power you will need.

PSU (Power Supply Unit) Types

Typically, you will see two types of PSU available: a "Regulated" (or "Linear"), and a "Switch Mode".

Regulated Power Supplies
- A Regulated PSU uses a Transformer to convert (typically) 230v AC to DC (Voltage can vary, but a CB usually requires 13.8v).
Transformers are heavy, quite large, and comparitively costly in parts and labour but they give a steady and "Clean" DC Voltage output which is clear of any spurious noise.

Switch-Mode Power Supplies -
A Switch mode PSU alters 230v AC to DC by cutting the power on and off very, very quickly. Then smoothing the supply so that it can be output to such devices as a radio. Therefore they need lighter, smaller and cheaper parts than a Regulated Supply resulting in a PSU that itself is usually significantly lighter, smaller and more cost-effective than a Regulated Supply. BUT, consider a light switch, sometimes there can be even a spark as the connection is made or broken, so there is the possibility of a "Spike" of radio noise.

A badly made, or cheap, Switch-Mode Power supply can therefore have the risk of making a Radio Noise each time it performs the on-and-off function to convert AC to DC. This may be heard on the radio as a minor, or even loud, HUMMMMM.
Some people have used Switch Mode PSUs for years with no problems at all and any such device sold for the radio market SHOULD be screened and "Radio Silent". But we have heard stories of people so annoyed with the PSUs that they have thrown them in the bin.

Many stories of Shack QRM (Radio noise at the Base Sation making the radios almost impossible to operate) are traced back to cheap Power Supply Units for things like Flat Screen TVs, Mobile-phone/Laptop chargers and similar, small PSUs.

Voltage and Amperage

What's the Difference?

"Volts and Amps are both measurements of electricity right? So what's the difference?"

There are deep and meaningful explanations about atoms flowing around electrons and charged particles that properly explain the difference, but in practical terms, sometimes it is easier to use a metaphor:
Think of a river, and the water is the Electricty. The River would be the wire or cable.

Voltage is the speed that the water is flowing
Amperage is the width and depth of the river
So the energy available (Wattage) from the river is a combination of the speed of the flow and the size of the river.

VOLTS

- Most CB radios, and Mobile Amateur Radios, are intended to be used in a 12v DC Negative Earth Motor Vehicle. A few radios can also be used, without modificiation, in a 24v truck and some very old models might expect to find a Positive Earth Vehicle. For the purpose of this section we concentrate on the 99%, 12v Negative earth.

Cars (and smaller commercial vehicles) are "Twelve Volt", but that voltage variues with the load on the vehicle at any time and might swing from 11v right up to 14 or 15v. So the OPTIMUM voltage for a CB (and other Mobile) radio is usually 13.8 volts

A PSU, bought specifically as a Radio PSU, will either be pre-set to deliver 13.8v, or the output voltage may be Variable. If it is a variable voltage PSU then an important part of the pre-start checks is to make sure it is set to 13.8v BEFORE powering-up the radio. Excessive voltage could permanently damage a radio, and insufficient voltage can cause the radio to fail.

AMPS

- The amperage is the Power that is drawn from the PSU and the more powerful the radio, then the more power it will need to draw. A PMR446 radio outputs half a Watt of radio signal and needs very little power, whereas an Amateur HF set might output 100w and need a lot more "Flowing Water " to run it. A big Linear Amplifier will want even more than the HF set.

Here are some typical Power usage numbers (approximate)

RADIO Legal 4w FM CB 12w SSB Euro CB 20w-30w "Freeband" CB / 10m Set Euro CB & 100w "Burner" Amateur 100w HF set Tokyo HL450b
Solid State
500w Amp

PSU Needed
(Amps) 2-3 5-7 10-12 15-18 25-30 60

If you have heard of "Joule's Law" (no it isn't a TV show about an American Private Detective) you may know that we can calculate, Watts, Amps or Volts provided we know two of the three.

Going back to the River-Water Metaphor, if we know how much water we want (30 watts worth), and we know how fast the River is flowing (13.8volts), we should be able to work-out the Width and depth of the river (amperage)

This is True, but it is not practical. Using Joule's Law we can calculate that a 100w HF Set should need (100/13.8= 7.25approx) Amps. So, according to the table above, why does it need 25-30 Amps?

We all know that energy is a constant and cannot be created or destroyed, so where do all those "extra" Amps go?

When you stop and think about it it is obvious:

The radio outputs 100w, so it needs 7.25Amps to send to the aerial
But that is assuming
- The radio does NOTHING else
- The radio is perfect, and 100% efficient
But we know it does other things
- It has an LCD Display - so something powers that
- It has a Signal Meter - needs power
- It has a Backlight
- It has a receiver
- It has an amplifier for the receiver Volume
- It probably has a microphone amplifier (Mic Gain)
- It possible has a pre-amp on the receiver
And we know there is no such thing as a perfect machine, there are always losses somewhere along the line and the MAIN Loss from a radio is Heat
- The XTALS get hot, so that is wasted power
- Other components get warm enough to make the whole case warm or hot to the touch
- and even the cable from the PSU to the radio is warming a little and losing some "Amps" before it even gets to the radio
So, when all the losses are considered, it isn't really surprising that a 100w HF Set needs a Twenty-five amp Power Supply. That'd be seven and a quarter amps to Transmit to the co-ax, and about seventeen to run the other radio bits and cover the losses.

It also explains why a Linear Amplifier needs less Amps-per-Watt than a Radio does: A 100w Linear would probably run from a 10 or 12a PSU, because it has few other functions (no meter, no light, no receiver, etc.), and (mostly) just losses from XTAL Heat.

One rule of thumb that is worthwhile is to buy the biggest and best PSU you can afford as it is VERY common for people to buy a PSU when they start out, then a bigger one, then a bigger one, etc..

Personally, I bought a 2a supply for a basic CB, then I bought a 7a supply for a small 10m Set, then a 10a for a more powerful 10m set, and finally a big, heavy, old-school 30a Regulated supply for my HF sets. Small PSUs are often hard to sell-on as their weight makes postage prohibitive, so a good idea to buy a bit bigger than you currently need and "future-proof" the shack a little bit.