Signal guide

Wireless sensor bursts (433/315 MHz)

Short on-off data bursts from everyday wireless gadgets.

What does it sound like?

Plate 78Sensor burst

A quick, crisp rattle or 'brrrt', repeating at regular intervals.

0 Hz1,0002,0003,000 Hz

5.0-second example. Recorded off the air on the developer's own receiver.

Field marksOn-off burstsRepeat every 30-60 seconds (weather stations)433.92 or 315 MHz

Who uses it?

Home weather stations, wireless thermometers, doorbells, car key fobs, tire-pressure sensors and remote controls.

Where and when can I hear it?

433.92 MHz and 315 MHz, repeating every few seconds to minutes.

Easily confused with

• Wireless meter and sensor bursts (868/915 MHz): FSK bursts shift tone instead of switching on and off