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wireless door bell into wireless relay

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videogudu

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wireless relay

Can someone please let me know how to use a wireless door bell to drive a relay at the receiver side.The output at the speaker of the reciver of the bell is a vibrating pulse of amplitude 0.5V.
 

wireless doorbell schematics

I think the amplitude is greater than 0.5V, it is probably the speaker loading down the output to that level.
Remove the speaker and then send the output through a diode and capacitor to form a half-wave rectifier. This will convert the pulses into a DC voltage. Use this DC level to drive a transistor which then turns on the relay. This will give a momentary relay closure to approximately the same length of time they hold the button down.

If you want to have a latching relay that remembers its state, you need to include a flip-flop.
 

wireless doorbell schematic

the output voltage to the spaker is 0.5V only , I checked removing the speaker .then it wont drive the diode.
 

wireless bell circuit

Trace the speaker wires backward into the circuit. I suspect that there is either a series capacitor or series resistor divider. The signal on the other side of this series element will be a higher amplitude one.

Note: since this is a wireless product, there is sometimes schematics available on the web. Look on the back for the FCC or equivalent ID code. This indicates which regulatory agency certified the item as staying within its power and frequency allocation. Using this number, you can sometimes find their application on the internet and it will sometimes show the schematic.
 

wireless doorbell circuit

Instead of getting output from the speaker better to trace the circuit & look for the pulse that triggers the Sound IC, feed that pulse to a Transistor then trigger the relay
thatz it ABC
 

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