Rule 35 Sound Signals in Restricted Visibility

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I have a FogMate and a 3 trumpet air horn, LOUD!
I forgot plus a RADAR reflector. The difficulty with the reflector is where to put it ina meaningful position

Where do you put the reflector on the AT? Mast? (Besides that, I have been considering an active reflector eventually, another electronics project LOL.)
 
Meanwhile +1 to the notes above that many VHFs have automated horn-via-hailer features.
Some do, but in my opinion they're rarely loud enough. From what I can calculate, a Standard Horizon VHF with 25W hailer output paired with their hailer speaker (103db at 1W/1M sensitivity) will produce 117db at best. That's below the required volume for any 40+ foot boat for a horn and won't be heard at any significant distance by someone inside a pilothouse.
 
Some do, but in my opinion they're rarely loud enough. From what I can calculate, a Standard Horizon VHF with 25W hailer output paired with their hailer speaker (103db at 1W/1M sensitivity) will produce 117db at best. That's below the required volume for any 40+ foot boat for a horn and won't be heard at any significant distance by someone inside a pilothouse.
Agreed, that's why we're getting the Kahlenberg switch. Automated hailer is better than nothing but not good enough.

The Kahlenberg seems very easy to install from the manual, just simple connection to the lead from the manual switch. We'll see.
 
There used to be a device called a “Fogmate” that could be installed onto any horn to automate sound signals. I never pulled the pin on a purchase and now they are no longer available. Kahlenberg has one that seems reasonable in price. They have more expensive options as well

You would think that after 60 years around boats my definition of "reasonable in price" would be closer to reality. However, $400 doesn't seem at all reasonable to me.

I'm a dinosaur.
 
You would think that after 60 years around boats my definition of "reasonable in price" would be closer to reality. However, $400 doesn't seem at all reasonable to me.

I'm a dinosaur.
Considering the Fogmate was under $150 when I bought it 5 years ago, I agree. For that price you can buy the controller Signal Mate sells and get more capability than the basic Kahlenberg unit gives.
 
Considering the Fogmate was under $150 when I bought it 5 years ago, I agree. For that price you can buy the controller Signal Mate sells and get more capability than the basic Kahlenberg unit gives.
I have rarely had to run in fog. However, the few times that I have, I could have easily been tempted to pay so someone $400 to hit the horn button on schedule.
 
I have rarely had to run in fog. However, the few times that I have, I could have easily been tempted to pay so someone $400 to hit the horn button on schedule.
We ran one of our boats from Seattle to LA. We spent over 24 hours in fog and the automatic function for the hailer was outstanding.
 
When I was running a research vessel on Lake Michigan I often used the hailer fog signal on the way to and from sampling stations, but used the big horn when on station because we needed the hailer intercom function. The big horn was a LOT louder.
 
After our collision the two skippers asked each other did you not hear my fog signal. When each said why did you not hear mine.
Turns out their auto signals perfectly timed duration were also perfectly in time with each other. Neither heard the other as his own signal drowned out the sound. :devilish::hide:
 
Considering the Fogmate was under $150 when I bought it 5 years ago, I agree. For that price you can buy the controller Signal Mate sells and get more capability than the basic Kahlenberg unit gives.
Makes me wonder how expensive it is to make a switch with a built in timer? I put a timer on my fuel transfer pump. I should think about the horn....

Edit: A little looking and I think I could cobble together a simple timer/relay together for around $75. That would include a On/Off/On panel switch, a programable timer, and a relay and a few bits of wire and connectors. So not terribly difficult. So if I could buy one that is professionally made for $150, I think it would be a good value. $400 I am not so sure.
 
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...Turns out their auto signals perfectly timed duration were also perfectly in time with each other...
I don't know about other makes, but my FogMate sounds the horn at random intervals, up to every two minutes (in the typical case of underway, making way) specifically to avoid this issue.

I agree a $150 price is quite reasonable, while the $400 option seems excessive. I paid $100 for my FogMate back in 2003.
 

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