Using a car horn with a Prop-1

[HauntedWolf]

Hi all,

My brainstorming continues for my Zombie Prom backdrop scare.  Is there any reason that a Prop-1 could not trigger a car horn like this one?

http://www.autozone.com/autozone/parts/Blazer-Horn/1989-Ford-F150-1-2-ton-P-U-2WD/_/N-ihbrzZ9citc?itemIdentifier=6073_48529_2497_

I think that all it takes a 12VDC across the terminals and the horn sounds.  Seems fairly easy to hook up, which makes me believe that I am missing something.  ;)

Any thoughts?

Thanks in advance!

[JackMan]

You'll need a relay connected to the Prop-1 and a Gel Cell or lead acid battery to power the horn. They draw way too much amperage for the Prop-1 to handle.

[JonnyMac]

Those things are loud because they draw a lot of current.  You can use an RC-2 or HC-2 to switch the your external battery to the horn. It's as simple as running a 3-pin wire from the Prop-1 to the amigo, then connecting your battery and horn to the output. The RC-2 may be a little more flexible for future use, as it has mechanical relays that can switch DC and AC. The HC-2 is DC only.

[HauntedWolf]

So,  how did I miss these Amigo boards?

I will have to give this some more thought, but it seem doable.

Thanks guys!

[jukingeo]

A suggestion:

Last year I wanted to do the same thing, but confronted with the large current requirement of real car horns, I decided instead to go all audio instead which requires much less current AND has an added bonus of being able to control the volume.

If you have an AP-16+ or other audio device with an amp,  get yourself a VERY efficient horn speaker such as this:

http://www.amazon.com/Pyle-PHSP5-8-Inch-Outdoor-Speaker/dp/B002UL0WH8/ref=sr_1_1?ie=UTF8&qid=1381689298&sr=8-1&keywords=horn+speaker

The AP-16+ is totally self contained and can be triggered on it's own.  Hook up the speaker to one of the output channels and put an audio file of a car horn on the SD card.   Let me tell you the sound is DEAFENING especially if the horn speaker is close by the trigger point.   

Keep in mind though that these horn speakers are NOT full range, they roll off the top and bottom ends (more so the bottom end) so it wouldn't be a good choice for a large monster growl or the like.  However, in the middle range (voice, horns sirens), the horn speaker is extremely efficient and doesn't need much power to get it to blistering loud levels.  Given the power output of the AP-16+, it can drive the speaker to a very loud level indeed.  I had the volume knob nearly all the way down and I was still scaring the crap out of people. 

Another benefit to an sound sample based system is that you can use other scary sounds besides a car horn.  One sound I had that proved to be VERY effective is of someone breaking glass.   Another was of a dog barking.  Since the speaker reminded me of a police siren, I used that one too...VERY effective.  Needless to say, I had quite a bit of fun with this one.   

Considering the money you will spend on a heavy duty power supply (or lead acid battery), the car horn itself, the audio route will probably cost around the same AND you could use the sound for other purposes down the road.

Geo