I'm trying to use my wireless doorbell to switch off my water pump. The problem is how to use the receiver signal to latch a relay. Search the net but no clear solution found !
I've driven LED from a speaker wire with transistor (doorbell receiver circuit) but don't know how to use this signal to latch a relay. I'm planning to use 6v relay. I've try to drive relay with transistor but no success.
I finally find the solution. It's on a Ron's site **broken link removed**. I've made changes in this circuit to suit my project.
Actually it's basic transistor latch, but it was hard for me to understand. After studying and experimenting Ron's circuit, I got the whole idea. Thanks Ron and all member of this forum for your reply/post.
Here is the circuit that latches a relay. Once I push the doorbell remote button, it stays on until I switch off the doorbell. I'll wire the doorbell remote with float switch and install it on overhead tank. When tank gets full the float switch will on and remote (transmitter) will send the signal to wireless doorbell (receiver) and my relay will activate. Thus it will switch off the pump..
As per what you said, i guess you are trying to operate a relay with chineese wireless doorbell where you connect a LED across the speaker and see it light when it sounds. But naturally connecting a transistor driver to the same place will not work You may try connecting a optocoupler in the LED's place and then trigger the Transisitor base. But naturally the power supply of the bell may not be capable of powering the relay. Cross check that first.
Cheers
It's not a Chinese wireless doorbell, in fact made in India and has a good range. I've seen the circuit and seems very satisfactorily. The power I've checked is more than 15v and sufficient to drive a relay.
Here is some misc. correction in my circuit, It works fine as I expected.