ORIGINAL: A.T.

Transmitters are limited to the actual RF output permitted and so all generally have, within lineof sight,equal range.
The receiver is themain limiting factor, except with 2.4Ghz the type of signal generated has animpact, and during range tests, the power down RF level.
When comparing range tests, the power down output should be verified to be all 10% of full power or make allowancesaccordingly.
AFHSS by Hitec has proven to be the least effected by obstacles.

Good reading:
Range Test - Comparative Range Test data on multiple systems **
note that the JR/Spektrum systems, used in this test, has twice the TXRFoutput permitted in other countries so the result must be downgraded accordingly when read by those in Uk, Europe &Asia etc.
Range of Transmitter and Receiver
Receiver - Operating Range
Receiver - Operating Range - Full vs ParkFlyer vs Backyard.
Range Problem
and especially for those still using 27<75mhz.
Range Problem - Transmitter Antenna cleaning
<dl> <dt>1. Aurora 9ch Power Down for Range Check is 1mw - tested to at least 1/4 mile.
2.2KM Rx was inside the car
"Today I did a car ground range test. Full power, not range check dedicated mode. Very impressed ! 2.2km ground level !!!
And must stop the test because of the field iregularities, even if we choosed a very flat area, the car passed behind a small (2-3m) hill
that blocked the signal completelly. I guess that this system can do more than 4km in the air ! I wrote system and not Aurora,
because was a module mounted on a T9C.
Did I mentioned that the Rx was inside the car, placed in the back, having direct vision to the transmitter via the rear window? "

2. An interesting Video of a Heli model with full telemetry, sitting in ground effect and demonstrating a range of 4/10th's of a mile
or about 2,112 feet. Keep in mind this is with many large obstacles in the way! The 2.4GHz scenario has changed somewhat?
Range test using Segway & GPS

AFHSS - Power Down for Range Check is 1mw - tested to at least 1/4 mile.

and much more under
"Receiver Operating Range, Range Test & Range Problem Solving" at
Alan's Hobby, Model & RC FAQ Web Links

Alan T.
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