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Types and makes of suitable radios

It can be very useful (and entertaining) to be able to receive local and international news, weather and sport wherever we are as we tour around the country without relying on internet connections and satellites with a good old radio (the electric wireless as some old Qld politician used to say).  

However there are many places where satisfactory reception is not available on the FM band and difficult on the AM band.   This page covers some options.
Generally speaking, the most useful radio receiver for your caravan will be a good quality AM/FM car radio with CD player with the longest telescopic aerial you can find.
Portable radios, the subject of this page, are for the most part markedly inferior in receiving weak signals by comparison.     But there are exceptions.
Limiting price to below A$500, the following are some of the radios available in Australia worth a mention.

 Sony ICFSW7600GR

are times where you will not have any useful signal, either no signal or constantly fading in and out.

However there are several of ways of improving the situation . . . .
*  a receiver with better sensitivity and selectivity,
*  tuning in to the HF shortwave band (see bottom of this page for explanation of frequency bands),
*  using a suitable external aerial to boost the AM broadcast band reception.
Two of these options means purchasing a good quality multi band portable shortwave radio.
There are a lot of multi band portable shortwave radios around but most for our purpose are worthless without an external aerial which I have covered further down the page.
The exceptions I mentioned previously in approximate order of how I would rate them is . . .





This isn't necessarily a complete list, I am looking forward to being able to add the Redsun RP3000 if it is half as good as overseas reports would indicate.

The latter, the Sony ICFSW7600GR at around $385 to $510 depending where you purchase (Aug 08), is the pick for my money.  To do any better than this you would need to be looking at a communications receiver starting from four or five times the price such as the Icom R75, a semi professional bench top HF receiver.   While not quite in that league, the ICFSW7600GR is still a very good performer and the Sangean ATS909 and Redsun RP2100 are not far behind.

With the ability to receive weak AM transmissions and world wide HF stations (including SSB for the Sangean ATS505, Eton/Grundig E5/G5, Sangean ATS909 and Sony ICFSW7600GR), you will never be without something to listen to and all in a package not much bigger then a paperback novel.
The following are all worth a look and rpresent very good performance for the money.

The Sangean ATS909 shown on the left, a little cheaper at around $320 to $400 is a close second but minus the synchronous detector of the Sony ICFSW7600GR but does have some other nice features.

Although it does have more bells and whistles, from my experience, the Sony has the edge where it counts, better AM & SSB (Single Side Band) reception.

(It was also marketed as Radio Shack DX-398 in USA & Canada, Roberts R861 in UK & Seimens RK-777 in Europe)
The Sangean ATS505, Sony ICFSW35 and Eton/Grundig E5/G5 at around half that price can give good results also.

Tevion MD81157 from Aldi, shown on the right, not too bad for the money at $50 and a better finish than the Sangean ATS505.

It covers LW 144 - 281 kHz, MW, SW 5.85 -17.9 MHz and FM with 240 station memory although in a volatile memory.

AM sensitivity and selectivity are not strong points but on par with others in this price range but FM is comparatively much better.
However, with the external aerial modification described later, this is very useful on the MW broadcast band, better reception than the radios in our car or caravan by a noticeable margin.  

I also describe a 12V power input modification.

Digitech  AR1745
, (This is a  Redsun RP300), also for $55.

It features direct key frequency entry as well as rotary knob and scan keys, 200 station non volatile memory, all of which is unusual in a cheap radio and is physically much smaller than all the others described here, pocket size at only 120x75x28mm.
Frequency coverage is 520-1710 kHz AM, 2300-7500 & 9500-22000 kHz AM and 70-108 MHz FM.

For a compact single conversion radio, it's performance really surprised me, a very sensitive AM receiver right through it's coverage range.  In fact, it's ability to receive weak AM signals isn't too far behind my Sony 7600GR.   Selectivity is reasonably good, for this price range.

It is let down by relatively poor sensitivity on the FM band and with only 100 KHz tuning steps.  But for our purpose it's the AM broadcast and shortwave performance that matters.

On the down side, common with many others with up/down button volume control it always turns on and off with an annoying burst of high level audio and coarse steps (a simple little mod goes part way to lessening the problem), auto scan only stops on very strong signals, Local/DX switch works on SW and FM only and the whole rational with the way the 200 station memory has been implemented needs a re-think.

But those criticisms aside, if you are after a radio that does an above average job of pulling in weak AM signals that you can slip into your pocket, this is a ripper.

On a performance verses cost basis in a pocket radio, this is the winner by a good margin.

When authorities advise you to have a portable radio in times of emergencies and disasters (bush fires, floods, cyclones etc), this radio is perfect, very sensitive, compact, good battery life and comparatively cheap ($55).

Digitech AR1747.  (This is a Redsun RP2100 also sold elsewhere as a Kaito KA2100, shown on the left.)

It is a fully featured PLL receiver and like the Sony and Sangean it is also has dual conversion.
Also, like the better ones from Sony and Sangean described above, this one covers 520 - 29999 kHz, 87 - 108 MHz FM, no LW (below 510 kHz) but this no great loss as is the lack of SSB.
It has a 50 station memory (but inconveniently arranged in 10 per "band" of 5).

It also has AM RF gain control and selectable band width filter (wide band is +/- 6 KHz and narrow band is +/- 3 KHz) as well as several other nice features not usually found in this price range.

The performance of this radio is outstanding and belies the price.   Sensitivity and selectivity on all bands is as good as the Sony ICFSW7600GR, it is very difficult to separate them on this score.
Although minus direct key entry, tuning is quick and accurate with two speed rotary encoder and a "Q Tune" (quick tune) key.
Audio is good with a large 125mm speaker and separate bass and treble controls giving 2.5W maximum audio output.

Power options are varied, external 240VAC and 9VDC as well as internal space for 4 "D" batteries and 4 "AA" batteries.  I power mine from 240VAC at home, 9VDC in the caravan (with a 12V-9V reducer) and have 4 "D" alkaline and 4 rechargeable "AA" Mi-MH fitted, the "D" and "AA" are selected by switch and the radio has a feature to recharge the batteries, very convenient.

It also has provision to use a long wire + earth or loop for the MF band and coax input for HF/FM bands.

It is physically larger than all the others mentioned on this page at 290x185x70mm with a reasonably large easily read and informative LC display.
I find myself using this radio more than my others, it's a very "likable" radio and as such, I highly recommend it, I haven't seen one that even comes close for $139.

For broadcast MF AM (530-1620 kHz), HF AM (1.7-30MHz - shortwave) and broadcast FM (88-108MHz) it's as good as anything I have used under $500. 
On a performance verses cost basis in a larger table/mantle size radio, I don't know of a better one.   I'll have a home for a RP3000, if and when it is ever released (which unfortunately is looking increasingly unlikely).

From Eton/Grundig range is the E5/G5 model (shown on the left) for around $225
AM/FM/LW  coverage 150 - 29999 kHz,  FM  87.50 - 108 Mhz ( 76 - 108 Mhz User Selectable),
PLL Dual Conversion AM/SW Circuitry with SSB,  700 Programmable Memory Presets,
Alpha-Numeric Four Character Memory Bank Labeling,  
Tunes Via Auto-Scan, Manual Scan, Direct Key-in Entry and Tuning Knob


Their flagship model E1 (shown on the right) has the lot including sync detector, switchable bandwidths and a large dot matrix LCD but is over three time the price of the E5/G5.
For bells and whistles it also trumps the Sangean ATS909 by a good margin but at over double the Sangean's price.
(Shown for interest only, would be way over $500 based on overseas prices at the time of writing, besides I don't believe this E1 model is available in Australia.)

All of the radios described on this page use PLL circuitry with digital frequency readout.

However be aware that with most cheaper receivers, the inherent sensitivity (ability to receive weak signals) and selectivity (ability to discriminate between adjacent signals) is usually comparatively poor.
Also those cheapies with PLL synthesisers and microprocessors, while they may look good on paper,  tend to generate considerable internal electrical noise which means that any weak signals they might have been capable of receiving are drowned out.
A half decent car radio will generally out perform most portable receivers in this price range.   If you are paying less than $100 (Aug 08), don't expect too much.     The Redsun RP2100 (Jaycar No AR1747) and Redsun RP300 (Jaycar No AR1745) are exceptions.
There are a few cheap "long range" AM radios, some under $50, on the market, my recommendation, don't waste your money, get one those described on this page.

As a rough guide, look for a radio with PLL (Phase Locked Loop) circuitry and digital frequency readout and preferably one that uses dual conversion.     Also a keypad is highly desirable for direct frequency entry and it simplifies storing/retrieving your preset frequencies too.

But beware, there a a few cheap and nasties with a digital frequency display that are not PLL, don't waste your money, if it doesn't say PLL, then it almost certainly isn't.



My choice . . .

   If I could only have one radio, it would be the Sony ICFSW7600GR at around $400,
   If I could add to that, a mantle size radio, it would be the Digitech AR1747 ( Redsun RP2100 ) for $139
   And if I could add a pocket size radio, it would be Digitech AR1745 ( Redsun RP300 ) for $55

      (Actually I do have all of these - plus a few more.     Prices as at Aug 09)

If I was on a budget and limited to one radio, it would be the Digitech AR1747 ( Redsun RP2100 ).

Why the Sony ?  Technically, in my experience, they have the edge (of these small portable types), they are well made with very good fit and finish and a solid feel.    Most importantly, they have a reputation for reliability and don't look or feel like they have been thrown together.    Also a full service manual and spare parts are available (and I have found Sony Aust to be very helpful as well).

One feature that sets this Sony apart from most other portables is the use of a synchronous detector.  This is not a gimmick, it really works.  Briefly, a synchronous detector goes a long way to reducing the effects of signal fade by replacing the fading carrier with a stable internally generated one.
Also with the Sony's +/- 1.5kHz fine tuning and excellent frequency stability, the SSB mode can be useful in reducing the effects of adjacent signal interference on DSB transmissions by selecting either the upper or lower sideband as appropriate apart from giving excellent reception of HF SSB transmissions. 

And Sony's flagship ICFSW7600GR is made in Japan too, the only one here that is, the rest are from China or Taiwan.
How long Sony will continue to make this model is anyone's guess, mine is that it will eventually be discontinued without being replaced, the same way their previous flagship model was, the brilliant SW77.

I expect to see all shortwave, world band radios, particularly the dearer ones, slowly disappear from the market as broadcasters such as the BBC and Deutsche Welle, cut back on their shortwave services as listeners abandon radio in favour of satellite etc.

Due to this lack of demand, manufacturers are concentrating on cheap AM/FM and digital radio.   So if you are thinking of a decent long range radio (there is still plenty to listen to and these radios are vastly superior on the domestic AM and FM bands too), get one while you still can.


External Aerials


Use any external aerial with caution and at your own risk.

Familiarise yourself with the potential dangers.

Do not use any external aerial while there is even a hint of a threat of a storm

any random crackling noises in the receiver can be an indication of potential or imminent danger.

Never locate an aerial over or under any power lines.

This can be and is a very lengthy technical subject but I have tried to reduce it into just some simple practical information. 
The following is some very basic information on the three types of external aerials for your radio to improve reception at your camp site.
Aerials that we are interested in here fall into three broad categories, loop, long wire and active types.


Loop aerials 

A very simple yet effective do-it-yourself one I will describe here is the non-resonant broadband aerial to vastly improve the medium wave broadcast band reception of weak signals particularly suited to less sensitive radios. 

Only perform the following modification to a battery only operated radio not one with a mains connection.

The essence of this is to wind 3 or 4 turns of insulated wire directly on to the ferrite aerial rod inside the radio and terminate the coil ends to a 3.5mm mono or stereo earphone socket which you will have to fit somewhere in the case of your radio.
If the radio case is metal not plastic, a stereo socket would be preferable with the coil terminating on the tip and ring only.
The aerial itself is nothing more than a length of wire forming a loop terminated in a matching 3.5mm plug.

Theoretically, the antenna loop length should ideally be as long as convenient but not exceeding 0.1 wavelength at the highest frequency, which is approximately 18 metres at 1650 kHz.
Obviously 18 metres is not practical for our traveling needs and in practice a 6 metre (2M+2M+2M) to 9 metre (3M+3M+3M) loop is good compromise.

Arrange the wire such that there is a horizontal component for best effect.  The loop, where length is less than 0.25  wavelength, is directional with maximum pickup in line (not broadside) and is referred to as a non resonant magnetic loop.
(Conversely, loops where length is greater than 0.5 wavelength have maximum pickup broadside, same as a ferrite antenna.) 

The loop can be contained in or held in a circular of rectangular shape by any non-metallic support such as PVC conduit etc or just hung up like a small clothes line to form a "delta loop" ideally with roughly equal sides.

My own antenna, shown in the photo on the right, comprises a 2M PVC conduit spreader supported by a 3.5M telescopic aluminum pole using two turns of antenna wire giving approx a 12M loop (an inverted equilateral triangle - not that that's important).

Alternatively, the loop can be arranged in a diamond configuration with a non-metallic spreader (a length of 25mm electrical conduit is ideal) and can be more convenient to erect.   A 1.5M spreader will give you a 4M loop and a 2M spreader will give a 5.5 - 6M loop

This is a very simple basic aerial but nevertheless works very well, is simple to implement, does not require constant retuning, is highly portable, easy to set up and not too critical on direction - a good compromise.    Also, loop aerials in general are less susceptible to inference than a long wire aerial. 

Whilst it's possible that selectivity may be slightly degraded due to the unmatched loading effect, this is of little concern since, generally speaking, we are out in the bush trying to pick up whatever we can.  (Trying to receive a weak distant signal adjacent to a strong local one is not a priority in this instance.)
And our antenna needs to be simple and easy to throw up at our camp site.
Having said that, I haven't noticed any degradation in selectivity during field testing.
With this modification to a couple of cheap portable radios and using just 4 metres of aerial wire, stations were picked up clearly that are totally absent without.    The performance of these radios from the aspect of receiving a weak medium wave broadcast band AM signal now is almost as good as my Sony IFCSW7600GR with just this 4 metre loop.

Unfortunately this is difficult but not impossible to implement on the IFCSW7600GR, the ferrite rod is difficult to access and the radio is so jam packed full that fitting another socket is difficult and the dramatic improvement seen on the cheaper radios is not seen with the Sony unless using at least a 8-10M loop although a 3-4M does give a small but worthwhile improvement.
The same goes for external inductively coupled loops, good results on cheaper radios, nowhere near us useful with radios the caliber of the 7600.

I have performed this mod on a Tevion MD81157 which has a readily accessible ferrite rod and plenty of room for an antenna socket, with excellent results.     It now pulls in weaker signals than either my car or caravan radios with just a 4 metre loop.
(Why did I buy the Tevion ?   It caught my eye for $19-95 (usually $49-95) in an Aldi sale that I attended out of curiosity.)

I did this mod on my Sony 7600 by fitting a 3.5mm socket in place of the wrist strap retaining screw, a very tight fit with some minor surgery needed.
I did it mainly so that I could use the Sony inside our aluminium frame aluminium clad caravan using an outside aerial and shielded feed cable.
In this instance my aerial consists of a triangular loop as described and shown in the above photo.
This works extremely well being able to receive all Qld, NSW, Vic and SA 50Kw ABC transmissions from anywhere in any of those states at night and several during the day.
A continuously variable RF gain control such as used by the Sony IFCSW7600GR, the Sangean ATS909 and the Redsun RP2100 (as opposed to the near useless Local/DX switch in cheaper radios) is near essential with an effective external aerial such as this one.

This aerial also gives good results with short wave transmissions.

Caution - some radios, such as the Sony IFCSW7600GR, that have an external aerial socket, have a superimposed DC voltage to power an active aerial.   In this case you should not connect a DC loop to the aerial socket directly, you have to make sure a capacitor is in series with the loop.

Before you go defacing your radio, wind the turns on the ferrite aerial rod and just lead them outside the case and connect it to  4 - 6 M of wire and arrange in a delta fashion as described with the wire 2 M or more above ground.   If you like the results, you can make the modification permanent.    It will however be the end of any warranty you may have.

Small loops

I am describing these just as a matter of interest, I don't believe they are quite as suitable for our wandering needs, my "cloths line delta loop" above takes a lot of beating in this situation.

This is another type of loop aerial consisting of the aerial wire, several turns of it, contained in a plastic loop (picture a hulla hoop) ranging in diameter from 300mm to 450mm.   Generally narrow bandwidth, they are tuned with a variable capacitor to suit the received frequency.  They tend to be reasonably directional.

The radio needs to be placed in close proximity, usually inside the loop since, generally speaking, there is no physical connection needed, they are inductively coupled to the radio.
They are commercially available and are reasonably effective and the cheaper the radio, the greater the improvement in reception.
There are passive and active (amplified) types.

Picture on the right is an example of a small amplified loop for the HF band connected to the radio's external input socket.

Then there are small loops (600 - 1200mm) with inductive or physical connection to the receiver that you can build yourself, both passive and active.

Non resonant long wire aerials 

Although out in the bush a length of wire 10 M or more long strung up a few metres above the ground with one end tied to a tree and the other attached to the radio's telescopic antenna can be quite effective on the HF and FM bands, once again, I'd suggest you be very cautious, especially if there is even a hint of a thunder activity or if you are picking up random crackles.

Normally only suitable for the HF and FM bands and will have no effect whatsoever on LW and MW which use the internal ferrite rod for these bands.
It does however work for a car radio on the MW and FM bands.

However, with the above modification to the radio, a short whip or length of wire connected to one side of the coil and the other earthed can give good results for LW and MW but in a camp site situation, an effective earth may be difficult to establish.
This works very well on a boat where connection to any underwater metallic object forms an excellent "earth".
This is probably beyond the scope of an introductory article like this but later, I may also describe a simple ATU (aerial tuning unit) and also a tunable active RF preselector (tuned amplifier) circuit for the MW broadcast band, either of which you could build yourself, for the more adventurous.

Active aerials

 These are a commercially available non directional (in the horizontal plane) vertical whips with an amplifier.
The radio would need an aerial input socket, not likely to be found on cheaper portable radios.

Some have small inductive loops which you place near your receiver for the LW and MW bands for radios without a suitable input connector for those bands.
Shown on the right is simple yet effective wideband active aerial you can build for under $10 using a 1M vertical whip for ease of use in a caravan.

 Modifications to the Tevion MD 81157 receiver 

This radio lends itself to very simple "improvements" due to the liberal amount of free space inside such as the aerial  modification described above and a 9 to 30VDC input, much more convenient than the original 6VDC one for several reasons.

The radio received the above aerial modification and in addition, one side of the winding is connected to the telescopic aerial so that the new external aerial works well on all bands, LW & AM as well as HF & FM.
Also, the 8 - 24VDC input modification means the radio can now be used with the external power simultaneously with the batteries so that you don't lose your preset stations if the external power is interrupted.
It can also be made to trickle charge internal Ni-Mh batteries (don't do this if you are using non-rechargeable batteries). 
Note - This mod is suitable only if the radio is to be used mostly with external power - reason, the combination of using lower voltage rechargeable batteries and loss across an isolating diode means the radio is only seeing about 4.5V instead of 6V, therefore onset of low voltage shutdown will occur after fewer hours use.
Also, depending on the quality/complexity of the radio circuitry, lower operating voltage can result in impaired reception performance.   Not applicable to high end radios like the Sony
ICFSW7600GR that maintain internal operating voltages  irrespective of battery voltage, up to their shut down point, with internal DC-DC converter circuits.
Just a small handful of components costing less than $10 is all that is needed and the two mods improve the performance and usefulness by a huge amount.

The accompanying photo show the new aerial input socket and the DC power socket below the original 6V input socket.

Of course, these simple mods can work with other radios too. 

 External power supply for the Sony ICFSW7600GR and other 6VDC radios

The Sony like many others is operated from 6VDC and that's what the radio's external power socket wants to see.   And in Sony's case they don't see fit to supply an AC power pack.

- while good 12VDC AC plug packs are very common, good regulated  6VDC ones are not, also
- it would be very useful to be able to operate the radio from the caravan and/or vehicle 12V battery.

A simple solution to both is to make a 12VDC to 6VDC reducer.   This is easily done with $5 worth of parts from Dick Smith, Tandy, Jaycar etc. 
All you need is the appropriate plug for the radio and a socket to suit your power supply, a 7806 regulator, tantalum capacitor and a small enclosure (mine is an old lipstick type dispenser - see photo).

This makes for a compact in-line connection between radio and power source.

Fortunately, the Sony uses a smallish (uncommon) size plug so that it can't be accidentally confused with the larger diameter more common sizes found on most 12VDC plug packs.

Now, using this reducer, any voltage between 9 and 30VDC can be used with the radio.   The output is maintained at a constant 6VDC.
The current capability of the regulator (which is rated at 1A max
,15W dissipation) will depend on input voltage and size of heatsink used.
In my case with a nominal 12VDC input and <250mA output, just a small one is needed which is obviously contained within the lipstick dispenser.
 The same circuit can be adapted to suit 3V, 4.5V or 9V radios too.

My present receivers (the better ones)
Icom R71A 100 - 30000 kHz   AM / SSB
Icom R7000   25 - 2000 MHz   AM / FM / SSB
Sony ICFSW7600GR 150 - 29999 kHz   AM / SSB  &  76 - 108 MHz   FM
My original from long long ago

It was a Nordmende from West Germany,
a better than average portable radio in its day (early ' 60s).

A three band 9 transistor radio covering, 
   LW -    160 - 280 kHz
   MW -   510 -1650 kHz
   SW - 1500 - 3500 kHz
Case was vinyl covered plywood

Some useful frequencies.

The following are some useful frequencies for listening to ABC shortwave worth programming into your HF receiver.

Keep in mind that the powers-that-be are forever changing many of these frequency allocations for one reason or another but they are right as far as I know in mid 08.

Time  Frequencies (KHz)
Sunrise   04:00 - 09:00  6020 6080 7240 7240 9660 9710 11650 15230 
Morning   09:00 - 12:00  9660 13690 15230 15240 17715 
Afternoon   12:00 - 16:00  9660 13690 15240 21725 
Sunset   16:00 - 19:00  5995 9660 9710 13690 15240 
Night   19:00 - 04:00  5995 6020 9560 9580 9710

The ABC broadcasts from Shepparton, Victoria on 11880kHz during the day and 6080kHz in the evening also,

Alice Springs 
Tennant Creek 
6020 kHz is a good ABC news transmission "after dark".

for AM and FM receivers, a good way to stay informed while you are away from home with world and local news and sport is with the ABC's almost 100% news radio stations.

A frequency list is shown on the right. 
(They are always expanding this service so check on their web site.) 

You can also visit their web site, there is a lot of interesting information there including dozens of links to other sites.


Adelaide      972 AM
Brisbane      936 AM
Canberra   103.9 FM
Darwin   102.5 FM
Gold Coast     95.7 FM
Gosford     98.1 FM
Hobart      747 AM
Melbourne    1026 AM
Nth Tasmania     92.5 FM
Newcastle    1458 AM
Perth      585 AM
Sydney      630 AM
Tuggeranong     99.9 FM

The following are the first three "pages" of preset frequencies that I have stored in my Sony ICFSW7600GR that I find very useful, all ABC of course. 
With the Sony
ICFSW7600GR (or a cheaper radio with the external aerial modification) you can expect to receive some if not most of the 50Kw transmitters listed below on pages 1 & 2 at night from almost anywhere.
For instance, reception in SE Qld at night - 
   -   all those listed from Qld - 100% of the time, no noise
   -   from NSW - 100% of the time, occasionally a little noise
   -   from Vic - 95% of the time, a little noise, occasional fading
   -   from SA - 75% of the time, usually some noise/fading
   -   from WA - 25% of the time, always some noise/fading
*The Sony is noticeably less prone to the effects of fading due to it's
synchronous detector feature although does generate some low level internal noise.

 Page 1    ABC 50Kw  Qld & NSW
1 612 4QR   Brisbane
2 792 4RN   Brisbane  (25Kw)
3 630 4QN   Townsville
4 1548 4QD   Emerald
6 576 2RN   Sydney
7 702 2BL   Sydney
8 549 2CR   Cumnock
9 738 2NR   Grafton
 Page 2   ABC 50Kw  Vic, SA & WA
1 621 3RN   Melbourne
2 774 3LO   Melbourne
3 594 3WV  Horsham
5 891 5AN   Adelaide
6 729 5RN   Adelaide
8 720 6WF   Perth
9 558 6WA  Wagin
 Page 3   ABC News Radio
1 585 6PB   Perth  10Kw
2 630 2PB   Sydney  10Kw
3 747 7PB   Hobart  2Kw
4 936 4PB   Brisbane  10Kw
5 972 5PB   Adelaide  2Kw
6 1026 3PB   Melbourne  10Kw
7 1458 2PB   Newcastle  2Kw
Frequency listing nomenclature as pertaining to shortwave listening.


Common  Terminology Transmission Range Principle Freq Spectrum
LW  (Long Wave) 150 - 510 kHz LF  30 - 300 kHz
MW   (Medium Wave) 510 - 1640 (1710) kHz MF  300 - 3000 kHz
SW  (Short Wave)  1710 - 30000 kHz HF  3 - 30 MHz
FM  (Frequency Modulation) 88 - 108 MHz VHF  30 - 300 MHz

The Frequency to Wavelength relationship.

 Band allocation by
 ( You will come across some minor
variations to that listed below.)

Frequency Range

Metre Band

2.250 - 2.550 120
3.150 - 3.450  90
3.850 - 4.050  75
4.700 - 5.100  60
5.900 - 6.250  49
7.100 - 7.400  41
9.400 - 10.00  31
11.500 - 12.150  25
13.500 - 13.900  22
15.000 - 15.900  19
17.450 - 18.000  16
18.850 - 19.100  15
21.450 - 21.750  13
25.600 - 26.100  11


Specific Frequency

The formula for converting a particular Frequency to Wavelength is,
Wavelength (in metres) = V / F
where V = velocity of light (300,000,000 metres per second)
For example, to convert 6.020 MHz to wavelength,
 = 300,000,000 / 6,02,000 Hz = 300 / 6.020 MHz = 49.8 M

Electromagnetic Frequency Spectrum




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