12 Volt Airhorns on Sailboats

[wingless]

Originally Posted by Pelagic

I have seen a few illegal horns fitted on small yachts.... The wrong frequency and Db rating for thier tonnage

Here is a good link for frequency and dB versus vessel size.

According to that document, the Kahlenberg Chimetone D-1 horns are compatible w/ Classes II, III and IV, for vessels sized 12-200 meters in length.

IMO, it would be very difficult to violate those regulations.

[endoftheroad]

Originally Posted by wingless

The thing to remember is that the horns are really, really loud.

The typical solution is to mount them on a hard top, directly above the helm. That way they are not pointed at anyone's ears.

Does that work on your boat?

Sounds like an ideal location to me but no hard dodger here.
Perhaps mounted on the underside of boom gallows?
About where my wife stands?

[wingless]

Another option is a whistle.

They are easy to mount, small diameter and vertical. They can be very loud, depending on air pressure and air VOLUME (CFM). They make a crisp, clear unidirectional sound. This is very handy to bounce an echo for audible ranging.

The down side is that they use LOTS of air. This one uses 56 CFM at 100 PSI.

A small whistle, like this Kahlenberg 115 is a nice option. An air solenoid would permit remote mounting / electrical pushbutton switch control, so this could be mounted anywhere up high on the mast.

Here is a test A/V clip of my Kahlenberg 115 whistle.