Stuck trying to connect 1.5v DC output from a digital timer to a piezo siren.

Thread Starter


Joined Nov 17, 2010
Hello. I am a small time tinkerer and I am stuck. I have a 1.5v dc digital timer and I want to replace the stock speaker with piezo siren that operates between 6-14v DC. Here is the link: Siren. From what I understand I will need a solid-state relay to connect the speaker output to the piezo siren and battery. I have searched 5 different stores and and searched the web, but I could not find a relay that would work at that low voltage. I hope that someone may know of a relay that would work, or know of a different way to do this project. I appreciate any help.


Joined Dec 20, 2007
The piezo siren (it is an electronic power oscillator) probably operates from smooth DC, not the modulated DC from the timer.
For a collector current of 150mA to drive the siren, the transistor needs a base current of 15mA (not just 0.7mA) but the timer probably does not have an output current that high.