Barking dog alarm project

[Agent360]

Hi Friends,

I am not much of an electronics buff. I understand the basics but I need a bit of help.

I want to build an alarm that is a barking/growling dog. The purpose is not home security.

My wife is into geocaching (http://www.geocaching.com/). We set up a night time geocache. You find it at night and it is supposed to be scary. I have already rigged a mechanical device that drops a scary mask. The cache is near a real pet cemetary. We have made a fake pet grave where the action happens.

I want to build a device that runs from a 12v power supply such as a motorcycle battery or a car battery. When the unsuspecting person triggers the event I want a dog to growlllllll and bark. I want it to be LOUD.

I found this on how to build one
http://kipkay.com/uncategorized/guard-dog-burglar-alarm/

This link shows how but it uses a doorbell as the trigger to make dogs bark. Problem is he is converting 120v (from the doorbell) to 12vdc which is what the sound module runs on.

I just want the whole thing to run on 12vdc. I plan to use a marine waterproof speaker and house it all in a water proof container. So when the person triggers the cache by either motion or trip wire (havent decided yet) they get loud growling and barking. The speaker and circuit box will be well hidden about 20 fee away. The point is to scare the crap out of them at night with scary dog sounds.

I need to know how to up the amps for the speaker so I can get volume and to make it all run off a car battery.

Any ideas.

Thanks
Agent360

[jimson]

All it takes is a little money.

I don't know how to get it all on 12 vdc but for remote 120 ac, a 12 Volt to 120 inverter would probably work.
http://www.amazon.com/Simran-DF1753-500-Inverter-Converts-Household/dp/B004UBMN0A

Then you could probably use a ready made option.
http://www.google.com/products/catalog?hl=en&q=rex+the+barking+dog+alarm&bav=on.2,or.r_gc.r_pw.&um=1&ie=UTF-8&cid=14044072425567654793&sa=X&ei=L-e0TfaJJYiPtwft8NHnDg&ved=0CDEQ8wIwAg#

To justify the expense, when finished with this project, you can use the inverter when camping etc and the alarm for your own house or something.

Be sure to put some small reflectors in the brush that look like animal eyes when hit with a flashlight.

[EskimoJoe]

All fun and games until you shock somebody into a heart-attack...

Have fun while it lasts..

[jimson]

We set up a night time geocache. You find it at night and it is supposed to be scary.

I think he'll be fine. The folks involved know it's suppose to be scary, just like the patrons of haunted house displays, where actors come after you with chainsaws and such.

I've never been required to sign a "heart attack disclaimer" prior to going into one of those.

[EskimoJoe]

I was more appalled at the 'unsuspecting person' part.

When the unsuspecting person triggers the event I want a dog to growlllllll and bark. I want it to be LOUD.

[jimson]

Well, the way I read it, it's supposed to be like a scary treasure hunt. The unsuspecting person just doesn't know what form of scare it will be.

[DREDIOCK]

Dunno. Seems to me it would be a whole lot easier if you just got a real dog

[jimson]

A mean dog chained out there in the middle of the night might actually be a liability issue, besides I think this is suppose to be a fun, clever project.

I get it 360, good luck on the project.

[Agent360]

LOL...get a real dog.

It all has to run on 12vdc. I need some hints on how to re work the circuit for that.

and yes I am trying to scare the holy crap out of "unsuspecting" visitors. If I can get one "i crapped on myself" finding this cache it will be worth any money i spend....heheheh

[VonMessa]

Anything to be an ass...

Try one of these      http://www.lowes.com/pd_77189-85538-LE-6140-A_0__?productId=1260279&Ntt=wireless+doorbell&pl=1&currentURL=%2Fpl__0__s%3FNtt%3Dwireless%2Bdoorbell

Geocaching is a blast.  there are are a bunch out in the Pine Barrens in NJ that we find when we go wheeling.

[morfiend]

 Agent,

  Have you considered a motion detector as a trigger? There's also infrared beam triggers that go off if the light beam is interrupted.  You could get lucky and find either one of these things in a electronics surplus store.



     

[DREDIOCK]

A mean dog chained out there in the middle of the night might actually be a liability issue, besides I think this is suppose to be a fun, clever project.

I get it 360, good luck on the project.

My chocolate lab would be perfect then. While my Golden Retriever was a protector. the lab is a caretaker.

Oh she'll bark. but get too close and she goes belly up and just wants her stomach scratched.
You stand a better chance of being bitten by a worm then my lab

[DREDIOCK]

Well, the way I read it, it's supposed to be like a scary treasure hunt. The unsuspecting person just doesn't know what form of scare it will be.

Here's a thought.
Haveta be done at night though to get the true effect.
Set the target to be at the grand canyon. About 6 feet off the edge of a cliff.

If that dont scare em. Nothing will 

[jimson]

It all has to run on 12vdc.

I'm sure it can be done, but if not, hooking an inverter to a car battery would probably give you a strong enough (for that) 120 outlet out in the middle of anywhere.

[gyrene81]

have you considered looking at the battery powered wireless doorbells and a battery powered bullhorn?