Air horns? how do they work?

Gday,
The small air horns you fit to your car usually has a switch that turns your compressor on and off, and dont run a tank. Id ask at your local truck shop for a kit, I reckon you would get a switch, solenoid, air lines and horn altogether.
Cheers

Most air horns I've seen (I use some currently) are just a relay for the supply, a compressor and the horns - no tank, as mentioned above - the pressurised air would run across a 'musical' reed I guess - I also guess that the pressure level would matter - too much, too little might bugger things up. Whole kits can be quite cheap - have a look in the budget auto outlets.

Why would you muck around when you can buy a set from $20 to $30 from Autobarn or Supercheap, probably K Mart too, with everything you need.

G'day mate, a truck air horn works differently to the ones you buy at auto shops because they have a air tank, like what you have. I am not 100% on it but you need to pipe the air from the tank to a electically operated solanoid valve which when operated allows the air to go to the horn. Most trucks run about 6 to 8 bar pressure, so if you are running your tank at air tool pressure 7 bar, then I would say that would be fine. When you wire the switch in try and have it so you keep both horns and they work off the same button on the steering wheel, just have a toggle switch to change from one to the other. This way your car will remane legal. The truck wrecker should be able to supply the solanoid straight off the truck.
Good luck.
Draff

I have a decent set of air horns which are set-up using a 3litre tanks and my Maxair compressor. You do need a solenoid/s to operate them. The horns I have came with a solenoid on each trumpet. I reckon you could quite easily use one as supplied by ARB with their Air Locker. It does the same thing.....you hit a switch and a blast of air is allowed to pass through until the switch is turned off (same as when you hit your horn button on the steering wheel. I just added mine into the same wiring circuit as the original horn....the trumpets are mounted under the right wing of the bullbar, out of harms way.

Air.