How Do Radio Control Transmitters Work?
Let’s take a closer look at the Radio Control, Transmitter. Radio Control Transmitters can come in many different shapes and sizes with switches, knobs, and buttons. They are commonly recognized by their antenna and dual joysticks used to control the model. Some may also feature a few LED’s to indicate whether the unit is on or off and maybe a few additional LED’s to also indicate battery level. The more expensive models may feature an LCD display for more elaborate status monitoring and feedback. As a power source the Transmitter ideally uses rechargeable batteries. However, alkaline batteries work just fine. Transmitters range from single function simple controllers most common to toy-grade RC’s, to full function controllers with a wide range of features. The single function controller found in most toy-grade RC’s simply make the toy go forward or backwards. The more advanced, full function controllers offer 6 levels of control with the dual joysticks for more precise control and maneuverability necessary for aircrafts. You can maneuver Forward, Reverse, Forward and Left, Forward and Right, Reverse and Left and also Reverse and Right.
The Transmitter generates a radio frequency alternating current and when applied to the antenna radio waves are created. Radio Control Models can operate on many different frequencies. Hertz (Hz), Megahertz (MHz), and Gigahertz (GHz) are the measurements used to describe these frequencies. The two most commonly used frequencies in toy-grade and hobby-grade RC vehicles in the United States is a set channel within the 27MHz and 49MHz frequency ranges. These two frequencies have been allocated by the FCC for basic consumer items, like garage door openers, walkie-talkies and of course Radio Control models and toys. Unfortunately, these two frequencies are very much susceptible to interference. An example of interference comes in the form of one RC vehicle interfering with another RC vehicle both running side by side. RC vehicles using identical frequencies operating in close proximity to one another will simply interfere with each other. Or one controller may attempt to control both vehicles. In an attempt to remedy this, most RC toy manufacturers make versions of each model for both frequency ranges so that you can operate two of the same model RC’s simultaneously for racing against each other. And most manufacturers provide a label identifying the frequency range that the RC vehicle operates in.
There are a greater variety of channels offered with the more advanced hobby-grade RC’s. The more advanced RC’s use 72MHz (Aircraft only) or 75MHz (Surface only) frequencies, these frequencies offer more set channels. For example, in the 72 MHz range there are 50 channels to choose from and 30 channels within the 75MHz range.
Commonly, the more elaborate hobby-grade vehicles use the 2.4GHz frequency range that incorporates special software in both the Transmitter and Receiver to virtually eliminate interference. Within this very wide frequency range the software automatically selects the best operating channel for you. With this there’s no need to worry about conflicting frequencies with other RC vehicles operating nearby.