Radio frequencies for use by Surface models (Boats & Cars)


In the UK there are a number of frequency bands that are allowed to be used by surface models.


Several frequency bands are for general use by all radio controlled models. These are the 27Mhz band, the 459Mhz band and the 2.4Ghz band and these can be used by boats, cars and aircraft as well as other modelling uses.


There is one frequency band which is dedicated for surface models only. This is the 40Mhz band. This band MUST ONLY be used for surface models.


Frequencies NOT for surface models

There is also one frequency band that is dedicated for aircraft use only. This is the 35Mhz band and MUST NOT BE USED BY SURFACE MODELS.


27Mhz Band. (26.960 to 27.280Mhz)

This was the original frequency band for all radio control modellers. The frequency being used is changed by fitting a pair of matched crystals in the radio transmitter and receiver.

In the early days only the single colour frequencies were available with spacing between frequencies of 50kHz. Then as electronics developed the intermediate split frequencies were introduced with spacing between all frequencies of 25kHz.

Originally this frequency band operated on AM (Amplitude Modulation) only but now modern sets can operate on either the AM or FM type frequency modulation and you should make sure that the crystals you are using are the correct type for the set you are using.


Crystals are available for 12 of the individual frequencies within this band as shown in table 1.


 

















TABLE 1

Frequency

Flag Colour

Flag Colour

Channel Number

26.975

Black or Grey/Brown



2

26.995

Brown



4

27.025

Red/Brown



7

27.045

Red



9

27.075

Red/Orange



12

27.095

Orange



14

27.125

Orange/Yellow



17

27.145

Yellow



19

27.175

Yelow/Green



22

27.195

Green



24

27.225

Green/Blue



27

27.245

Blue



29

27.275

White (See note below)




Note. - Manufacturers kept the 27.275Mhz channel for their own use.


27Mhz Frequency control

Modellers should display the appropriate colour flags/ribbons from their transmitter aerial to show which frequency they are operating on to other modellers. Within our club members should also use the frequency pegboard to control the use of this frequency band.


40Mhz AM & FM Band. (40.660 to 41.000 Mhz)

This frequency was introduced at a similar time as the Aircraft 35Mhz band and was to allow the continued safe use of models at a time when the 27Mhz band was being swamped by the use of CB radios.


The frequency being used is changed by fitting a pair of matched crystals in the radio transmitter and receiver. However unlike the 27Mhz band each individual manufacturer adopted a different standard for their crystals and they cannot be interchanged between different manufacturers equipment. Also this band uses both AM (Amplitude Modulation) and FM (Frequency Modulation) radio transmission types so even within a particular manufacturers equipment you must use the correct set of matched crystals for the radio type being used. All 40MHz frequencies operate on a 10Khz frequency spacing.


Manufacturers make crystals available for 34 of the individual frequencies within this band as shown in table 2.


TABLE 2


Frequency

UK Channel Number

Flag Colour

(with UK channel number)

European Channel Number

40.665

665


50

40.675

675


51

40.685

685


52

40.695

695


53

40.705

705



40.715

715


54

40.725

725


55

40.735

735


56

40.745

745



40.755

755



40.765

765


57

40.775

775


58

40.785

785


59

40.795

795



40.805

805



40.815

815


81

40.825

825


82

40.835

835


83

40.845

845



40.855

855



40.865

865


84

40.875

875


85

40.885

885


86

40.895

895



40.905

905



40.915

915


87

40.925

925


88

40.935

935


89

40.945

945



40.955

955



40.965

965



40.975

975



40.985

985



40.995

995



40Mhz Frequency control

Modellers should display a Green flag from their aerials with black or white numbers corresponding to the UK channel number. eg. if using 40.805 then a green flag with 805 in black or white should be displayed. Within our club members should also use the frequency pegboard to control the use of their frequency.




2.4Ghz Band. (2.400 to 2.4835Ghz)

This is the most up to date frequency band and utilises all the magic of modern electronics.

There are up to 80 individual frequencies available within the frequency band.  


The frequency being used automatically controlled by the transmitting set so there are no crystals to worry about. A process known as ‘BINDING’ is carried out when you first install your radio into you model and switch on for the first time. This process varies with individual sets but ensures that your transmitter only talks to the receiver being used in your model and nobody else’s model.


This system is normally OK for most club sites, but in cases where a very large number of modellers operate together there may be issues with frequency clashing. In the event of a frequency clash the system will normally shut down to a failsafe condition.


2.4GHz Signal Range

There are two basic types of system as regards to operating range. The full range sets are as stated FULL RANGE. These sets have two receiver circuits in the receiver and can be identified because the receivers that have two aerials. The advantage of two receivers is that the two aerials can be aligned in the vertical and horizontal plane to give maximum range. They also have signal checking between the two received signals to improve signal rejection. The park flyer or short range receivers only have a single receiver circuit and hence a single aerial so they have a limited range and signal rejection capability. This limited range is normally OK for small models such as a small slow moving boat and if operating with a small number of other users. It is recommended that for faster or larger models or where a larger number of users are operating on 2.4GHz the full range systems are used since it is less likely that the signal will be lost.


2.4GHz Frequency control

There is no need to have any frequency control such as the flying of flags or a peg board since the electronic technology takes care of the frequency allocation.


More information

If you require further information of frequencies that are allowed for modelling use in the UK the please refer to the United Kingdom Radio Control Council Website. At http://www.ukrcc.org


Other Frequencies

35Mhz AM & FM Band.(34.945 to 35.305Mhz)

This Frequency band is ONLY for aircraft models and MUST NOT BE USED BY SURFACE MODELS.


459Mhz UHF Band. (458.5 to 549.5Mhz)

This frequency was introduced in the 1980’s, but was an expensive version of radio and was mainly used by aircraft modellers although there are no restrictions on its use for modellers. It is not thought  that any manufacture makes equipment for this frequency now but it is still OK to use if you do have the correct equipment.


The frequency being used is changed by fitting a pair of matched crystals in the radio transmitter and receiver. All 459MHz frequencies operate on a 25Khz frequency spacing.


This band is only permitted within the UK and while equipment was once available it is unlikely that many members will be using this equipment.







A printable PDF copy of the above is available on our

Club Reference Documents page