SCSA Glider Advice

The Radio
As with the gliders there's a large variety of Radio Control (R/C) sets available.

Important facts
R/C sets are available on 4"bands":

• The27Mhz band - for use by anyone, i.e. planes, boats, cars.

• The 40Mhz band - purely for ground based models, i.e. cars and boats.

• The 35Mhz band - reserved for aircraft only.

• And the newest band 2.4Ghz - available from summer 2007

This means that you although can use the 27Mhz band radios (which tend to be cheaper), you may get radio interference (and a crashed model) from anyone using a R/C model car near you. A 35Mhz band set is a much better choice for the glider/aircraft flier. However the new 2.4Ghz sets are the very best choice, because the way they work means that they are pretty much guaranteed interference free.

Within each "band" there are a number of separate frequencies available.

• If you had 2 people flying together on the same frequency, then the radio's would interfere with each other and both models would probably crash.

• The 27Mhz band has frequencies designated by colours, i.e. red, blue, green etc

• The 35Mhz band has frequencies designated by numbers i.e. 57, 58 .......84, 85, 86 ...90.
  Most clubs operate an "even frequencies only" or an "odd frequencies only" rule to reduce the chances of interference - so it's best to check what rule applies in the club you are thinking of joining.
  The SCSA operates an even frequencies only rule.

• The frequencies are controlled by plugging in different "crystals"

• The 2.4Ghz sets work on a totally different principle and don't have seperate frequencies as such. Instead the radios constantly monitor the whole of the 2.4Ghz band and automatically set and change frequencies, meaning frequency clashes are impossible.

The radio set.
The radio control (R/C)set consists of a transmitter (the bit you hold) and in the model are a receiver, servo's and a battery. As you move the stick on the transmitter (Tx) it sends a signal to the receiver (Rx), which sends a signal to the servos, which then move the arm on top of the servo in response to you moving the Tx stick. This arm is then connected to the control surfaces on the model via some sort of pushrod. Please see the pictures below.

The most popular manufacturers of radio control radios are Futaba, JR, Multiplex, Sanwa, Spectrum and Hitec. The cheaper R/C sets are usually 2 channel (meaning you can only control 2 functions on the model, e.g. rudder & elevator) and the more you pay, the more features you get. As an example the Tx pictured below is computer controlled, has 8 channels, 8 model memory (meaning you can switch easily between 8 model set up's on the same Tx) and lot's of bells and whistles, however it costs over £300 just for the Tx!

An average 2 channel set will cost about £50, however if you can afford it you are much better off spending a bit more and getting a 4 or 6 channel set with a few extra features. Useful features include servo reverse and "rates". These make it easy to set up your model so that the controls work in the right direction. Another very useful feature is extra model memories. This enables you to use the same Tx with several models and you can change models Tx easily, just by pressing a few buttons.

This photo shows a typical receiver (Rx), servo and battery pack.

The Rx is the black box on the right, the blue object is the battery pack and a servo can just be seen within the red fuselage (It's the small black thing on the left with the white L shaped arm)

In the bottom RH corner of the receiver you can just see the top of the crystal.

This photo is about 2/3rds full size. 

Picture of a crystal. (as can be seen from the label, this crystal is channel 80 on the 35Mhz band..actually = 35.200Mhz)

NB: this photo is at roughly double actual size.

A radio transmitter (Tx).

Note this is a "top of the range" Futaba FF8 and has lots of extra knobs & switches.

The typical beginners Tx is usually much more simple than this.