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Step 6: Extra Chime

Picture of Extra Chime

So the setup worked fine on the bench, but what would happen IRL? I wanted to only have a single doorbell outside to save confusing visitors, but at the same time wondered what would happen if someone pinged it while I was unable to answer the call, or if someone else was in the house and didn't hear the Duo call coming through.

The answer to these worries was to include a standard wireless doorbell transmitter in the build, that would pair with our existing chimes in the house. This way the "normal" doorbell would ring even if the Pi part of the build stopped working for some reason.

I ordered a compatible doorbell button from Ebay (used, £2.50) and after some testing soldered two flying leads to the microswitch contacts of its circuit. This meant I could chop down the doorbell's plastic case and connect my own lever switch to trigger the chime.

Having this fail-safe made me feel a lot better about using this project "in the wild" and also added functionality for very little money - some video doorbell vendors will charge you up to £50 if you want an extra chime unit!