shorter than expected RF range

I’m working with an RF transmitter/reciever that I borrowed from a surplus Oulia wireless door chime. When the transmitter is triggered the receiver triggers an event wirelessly. Both are housed in thin plastic boxes.

The transmitter advertises 150m or 450 feet range in open space. When I tested the range, it got about 50 feet of reliable receiving, and through a wall it gets about 20 feet. Thats not good enough for what i’m using it for.

My voltages are 11.8v to the transmitter and the receiver has a fresh pair of AAA’s.

Does anyone have any advice to increase the range?

Remove the wall :D

The wall should probably stay... but are there any suggestions for a transmitter pair with a bit more power?

XBee radios work well.

Add appropriate antennas for your freq. Match the orientation too. Try NiMH AAA batteries. Check for colliding devices (using same freq). Drill an array of 1-inch holes in the wall. :-X

The transmitter advertises 150m or 450 feet range in open space. When I tested the range, it got about 50 feet of reliable receiving,

Yes I suspect you don't have the "trades description act" in your country which makes untrue claims illegal.

Also the range will probably be based on open field tests, that is line of sight, no buildings anywhere close to give reflections and no other electrical activity to give interference. The sort of reduction in range you see is typical when you move into the real world.

Capio gave good advice about adding appropriate antennas, you can get them with a high gain but they are then directional, Does this matter in your application?