Call on a chip UMS
On a widespread chip series UMS, in particular US-08, you can collect a doorbell on the basis of subscriber loudspeaker.
If you install the chip on the socket, You will have the opportunity to check the performance of other series ICS UMS. The diode bridge should be designed for a voltage of 400 V. Should observe safety precautions when mounting the device, i.e. it has a transformerless power source