Alarm Siren Delay

Printed From: the12volt.com
Forum Name: Car Security and Convenience
Forum Discription: Car Alarms, Keyless Entries, Remote Starters, Immobilizer Bypasses, Sensors, Door Locks, Window Modules, Heated Mirrors, Heated Seats, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=71154
Printed Date: July 14, 2025 at 1:43 AM

Topic: Alarm Siren Delay

Posted By: brentmck66
Subject: Alarm Siren Delay
Date Posted: January 20, 2006 at 3:09 AM

I have 2 extra piezo sirens hooked up in my car, with a relay. I was wondering how I can delay these sirens from going off instantly. Something like 5-10 seconds. I want all of my alarm sirens (total of 3) to be on the delay

1 normal siren under the hood, and 2 piezo sirens inside the cab.

Replies:

Posted By: 76eldoconvertfi
Date Posted: January 20, 2006 at 2:19 PM

A note about additional sirens. If you install additional sensors, particularly an ultrasonic, DO NOT wire an internal additional siren to the normal underhood siren output. What happens is that "warn" chirps trigger the ultrasonic full alarm. It will drive you crazy. What I ended up doing with my mini-piezo that's under the dash, (AKA - thief with his head up under the dash pain generator), is wire it to the horn honk output so it only goes off on a full alarm.

Posted By: brentmck66
Date Posted: January 20, 2006 at 3:41 PM

My alarm has a silent on off option, so I have always used that. Some alarms have an output on them for extra sirens. It is about -15 here and snowing, I am going to install this as a temporary measure. Once spring comes, I will see if my brain has extra siren outputs.

I found this pulse timer on ebay, and was wondering if it would work.

https://cgi.ebay.ca/dll?ViewItem&item=5856292102&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1

My alarm is a Compustar 1WAM4R

Posted By: brentmck66
Date Posted: January 21, 2006 at 12:28 AM

will that pulse timer work?, and is it installed just like a normal relay, but instead of male connectors it just has wires?

Posted By: dualsport
Date Posted: January 21, 2006 at 1:12 AM

Don't think that pulse timer is what you're looking for; it probably puts out a 1 to 90 second output immediately upon triggering, instead of a delayed output.

You could use something like this to get a delayed siren output-

posted_image

If you put it together, add an extra diode between term 85 and 86 of the relay coil, stripe towards 85, to clamp the turnoff voltage spike-

Cost for parts other than the relay should be less than 50 cents- if your siren doesn't draw much current, you might even be able to do without the relay, and just ground switch the siren instead. If it uses more than a half amp, you could parallel the transistors for more drive capability; you just have to tack on another 10 cents for each transistor-