This is my plan to enable an existing screamer inside a car to work with a new alarm system, which doesn't have a dedicated 12v output when the alarm trips.
- parallel the siren output with the input of a bridge rectifier
- feed the output of the rectifier to a 4n25 via a current-limiting resistor
- use the output of the 4n25 to control a small 12v relay
- use the relay to drive the piezo screamer
Does this seem OK? I'm guessing if it works then there will be a slight drop in the siren's output?
- parallel the siren output with the input of a bridge rectifier
- feed the output of the rectifier to a 4n25 via a current-limiting resistor
- use the output of the 4n25 to control a small 12v relay
- use the relay to drive the piezo screamer
Does this seem OK? I'm guessing if it works then there will be a slight drop in the siren's output?