Wireless weather stations, car keys, wireless door bells and several other telemetry devices are transmitting their information into the air in the 433 MHz band.

The modulation type which is used for these devices is mostly amplitude-shift keying, ASK. The most common ASK form is On-off keying, OOK.

The following signal is transmitted each minute somewhere near my living area.

The total bust is about 0.85 seconds, in here you can see that it is divided into 11 parts :

And this is the first part, 0.08 seconds:

[to be continued…]