📻 Radio Control

Transmitters, receivers, and the protocols that connect you to your drone

How Radio Control Works

Your radio transmitter sends control signals to a receiver on the drone. The receiver passes commands to the flight controller. In 2026, ExpressLRS (ELRS) has become the dominant protocol, offering the best combination of range, speed, and price.

2026 Standard: EdgeTX firmware + ExpressLRS protocol + 2.4GHz band. This combination offers 1000Hz update rate, 10km+ range, and costs under $100 for the transmitter.

Radio Protocols Comparison

Protocol	Frequency	Update Rate	Range	Open Source	Price
ExpressLRS	2.4GHz / 900MHz	25-1000Hz	10-50km	✅ Yes	$10-20
Crossfire	900MHz	150Hz	40km+	❌ No	$50-80
Tracer	2.4GHz	250Hz	5km	❌ No	$50-70
FrSky ACCST	2.4GHz	9ms	2km	❌ No	$15-30
DJI RC (SBus)	2.4GHz	7ms	10km+	❌ No	Built-in

ExpressLRS (ELRS) Deep Dive

ExpressLRS is an open-source radio control protocol that has revolutionized FPV. It offers the best performance at the lowest cost, which is why it's become the industry standard.

ELRS 2.4GHz vs 900MHz

Feature	2.4GHz	900MHz
Update Rate	25-1000Hz	25-200Hz
Penetration	Good	Excellent
Range (default)	10km+	30km+
Antenna Size	Small	Larger
Best For	Freestyle, racing	Long range
Packet Rate	500Hz (sweet spot)	100Hz (sweet spot)

ELRS Setup

Flash ELRS firmware to TX module using flasher.expresslrs.org
Flash ELRS firmware to RX with same binding phrase
Set packet rate (250Hz recommended for range, 500Hz for racing)
Bind: power cycle RX 3 times within 30 seconds of powering TX
In Betaflight: set receiver to CRSF protocol on the correct UART

Recommended Transmitters (2026)

Transmitter	Price	Protocol	Gimbals	Best For
RadioMaster Pocket	$65	ELRS	Hall	Budget, portable
RadioMaster Boxer	$100	ELRS	Hall	Best value
Jumper T20S	$110	ELRS	Hall	Compact, feature-rich
RadioMaster TX16S II	$150	Multi	Hall	Multi-protocol
RadioMaster TX15	$139	ELRS	AG01 Hall	Premium feel
DJI FPV Remote 3	$199	DJI	Hall	DJI ecosystem only

Firmware: EdgeTX

EdgeTX is the open-source firmware that runs on most modern transmitters. It's a fork of OpenTX with more features and active development.

EdgeTX Features

Custom mixes and curves for precise control
Logical switches and special functions
Model profiles (up to 60+ models)
Telemetry display (battery voltage, RSSI, GPS)
Multi-protocol support
Color touchscreen UI (on supported radios)

Receiver Options

Receiver	Protocol	Size	Price	Notes
BetaFPV ELRS Nano	2.4GHz ELRS	10x10mm	$15	Tiny, great for racing
Happymodel EP2	2.4GHz ELRS	15x12mm	$12	Budget choice
RadioMaster RP3	2.4GHz ELRS	15x12mm	$18	Diversity antenna
BetaFPV SuperD	900MHz ELRS	20x15mm	$22	Long range
RadioMaster RP4TD	2.4GHz ELRS	20x15mm	$25	Dual antenna diversity

Control Rates & Expo

Rates determine how fast your drone rotates at different stick positions. Expo adds a dead zone around center for fine control.

Style	Rate	Expo	Max deg/s
Beginner	0.5-0.7	0.3-0.5	250-350
Freestyle	0.7-1.0	0.1-0.3	400-600
Racing	0.8-1.2	0-0.1	500-800
Cinematic	0.4-0.6	0.4-0.6	150-250

Antenna Placement

Mount RX antenna away from carbon fiber (blocks RF)
Use zip ties to keep antenna rigid and exposed
For diversity: mount antennas 90° apart
Keep antenna away from VTX antenna (interference)
T-antenna: mount vertically for best omnidirectional coverage

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