-  Choosing a model -  Choosing an engine -  Your transmitter -  Flight controls
	Your Transmitter Radio equipment is usually characterised by the number of functions, or channels that it has. One channel provides a means of control over one function on a model - rudder for example; 8 channels provides control over 8 functions. These channels can be proportional - that is, when the control stick on the transmitter is moved it causes the corresponding control on the model to move, and the amount of control surface movement is proportional to the stick movement; a small stick movement produces a small control movement and so on - or it can be switched, that is, a switch on the transmitter causes the control to move from one position to another by a fixed amount. The most basic equipment has two channels, or functions, which are usually operated by 2 separate sticks: one moves up and down, and one moves from side to side. This may be all that is required for a simple glider; one stick moves up and down to control the elevator and one moves from side to side to control the rudder. The next step up is a set with 4 or more channels. In this case the controls are arranged as 2 sticks, each of which can move both up and down and side to side. These 4 functions are then used to operate throttle, rudder, elevator and aileron, although the exact arrangement of which stick operates which control can vary, depending on the mode of the transmitter. The 5th and 6th channels are switched and are operated by the switches on top of the case. This illustration shows a typical non-computerised 6 channel 35MHz FM radio transmitter, with an indication of the purpose of the various controls.