Wireless doorbells are very popular today because of their easy setup and pretty low price. The only flaw is that we know all about how they operate. Frequency is 433.92 MHz and they use primitive signal encoding.
Here we can see a device that consists of a 433.92 MHz transmitter module and a microcontroller that emulates pressing a button on bell's remote controller. The thing is that this "remote" is universal and it triggers every doorbell in range within a few seconds. Method used is brute-force that sends out all 2^12 or 4096 codes that original HT12-E produces. Now the only question is whether you are going to use this device to annoy all of your neighbourhood or to open their garage doors.
[ Source: Furrtek ]
The Wireless Doorbell has proven to be a great tool for many homeowners. Although it is a
relatively new invention, it has had a dramatic effect on the doorbell industry. Many
homeowners have wrestled with the decision of whether to add it to their home.
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