Hello, new associate member here. We recently arrived in Fort Lauderdale after an 8-month cruise to Nova Scotia and back, none of it on the Intracoastal as our masts are a bit too tall.

In Maine and New Brunswick we used hand-held compressed air horns with a certain frequency because of fog, and did not like:
[ol]
[li]Low volume for marine application[/li]
[li]Debilitatingly high noise at only arm 's length[/li]
[li]The cans run out at the most inconvenient times[/li]
[/ol]
And so we are quoting installation of a 123 db electric horn, twin trumpets, to be installed on our mizzen mast, probably just above the dome of the radar antenna. Now, we can 't seem to find a supplier for a protecting ring in metal to go horizontally around the 18-inch horns, to prevent getting snagged by the mizzen ballooner or mast halyard.

Any comments on the whole (harebrained?) idea, on the protecting ring, on pressurised air (131 db) vs. electric (123 db) horns, and on mizzen vs. main mast is most welcome.

Cheers,

We also use a Raymarine hailer via the VHF. I guess mine must also be circa 40dB. I can 't tell whether that is "enough". DeciBells being a logarithmic scale, 120dB is many times louder so it can 't harm. But I question whether even that will be heard on the bridge of a freighter above the engines as it hammers down on you at 12 knots.

I think AIS is the best restricted viz tool these days. I assume you broadcast AIS as well as receive? If not, that 's where I 'd spend my dollars.

Finally, some kind of protection against stray halyards is sensible. Mine is mast mounted just below the radar dome and it really shouldn 't possible for a halyard to get there - but it did, half way between Galapagos and Marquesas. The hailer dangling and swinging around on the power wires is not a good idea - we had to send someone up the mast twice to get it secure - inevitably at night - it took about three hours. Deepest joy!