Radio Control Transmitter
Radio Control Transmitter (TX)
The control to any RC model comes from the Radio, also refer to as Transmitter, and abbreviated as TX. The TX is responsible for translating users input into wireless signals and sending those signals to a Receiver (RX). There are two types of Radios in the market place, Surface and Air. For Drones/FPV we use Air type Radios. These Radios will be the focus of this Wiki.
The anatomy or components of a Radio often dictate the cost.
Here are the Basics:
Wireless Link - This is the most important part of a Transmitter, without it, all you have are sticks and switches that will do nothing. The wireless link has its own set of elements like Protocol Type, Frequencies, Number of Channels, Antenna, Telemetry, and more. Most of the time protocol, frequency and channels are often developed and controlled by the manufacture of the transmitter and are not often interchangeable between them. In other words, the Wireless link of your transmitter (TX) and receiver (RX) must match. Picking a radio will determine your selection of receivers.
Gimbals - Refer to as Sticks. These are the Main control element of the Radio. There are two main types of Gimbals: Potentiometer (Analog) and Hall Effect (Digital). Hall Effect being the most desired these days. Although configurable, one gimbal controls to channels.
Switches - The other element of user control comes in the form of switches. There are many types of switches but for Air type Radios there are two main types of switches, Positional and Sliders. With Positional switches, 2-post, 3-post, & momentary are the most common for our hobby. The main difference between Position switches and Sliders is what they can communicate (or control). Position switches have only a very few variables (2 or 3 hence the 2-post or 3-post). Sliders have much more variables much like a gimbal. Although highly configurable these days, one switch controls one channel.
Operating System (OS) - A huge difference between the Radios we have today versus the Radios from 10 to 15 years ago is they are computerized. Like with computers, there are different Operating Systems that control how the Radio works. The configurability of the radio comes from the OS. Most manufacturers develop and control their own OS much like the wireless links. Just like Computer OSes, there are open source projects for Radio OSes. The biggest being OpenTX.
Other Features, can be Display, External Module bay (to allow other wireless link types), Size, Sound, Microphone, BuddyBox (aka Trainer mode) wired and wireless, Removable Antenna, Battery type/Charger, On-board memory, PC Gaming Remote, and much much more.
Many Radio manufactures exist for both Air and Surface radios. But for Drone/FPV/Multirotors we used a select few (Ordered by most common):
Not so common manufactures:
- JR - The company everyone copied from to the point they are no longer around.
- And many others