12v foghorn system?

[Refueler]

I'm familiar with rule 34 (actually *both* rule 34s but let's not go there). What I was questioning (and I may have misunderstood) is the implication in refueller's earlier post that your own sound signals should somehow be different after you "make audio contact". If nothing else I'm not sure how I would know if/when another vessel could hear me. I'm sure there are plenty of conventions applied by masters of large commercial vessels which arent In the colregs but that doesn't make them best practice for small yacht sailors

The sound signals are as per ColRegs ... that is the foundation. No dispute.

My comment is that once audio contact is established - its possible that blasts and answering blasts made to enable each to pass or avoid safely. It is not a case of just doing what you imagine to do ...

Long debates in Marine colleges over proceeding in restricted visibility ... not only sound signals - but also speed. When the rules changed in the 70's ... they introduced the questionable 'Radar assisted vessels may proceed at higher speed than those without' - that caused a real debate for years ...

The fundamental function of the ColRegs is to define a minimum standard to follow. To avoid close 1/4's situation. Same as Highway Code on the road.

 

[laika]

My comment is that once audio contact is established - its possible that blasts and answering blasts made to enable each to pass or avoid safely. It is not a case of just doing what you imagine to do ...

apologies but I'm afraid I'm still not following. What counts as "audio contact"? How do I know the other vessel can hear me? And how can manoeuvring signals be effective in restricted visibility if I can't see the aspect or position of the other vessel? Perhaps there are other unstated assumptions in here such as radar and vhf contact Which may be assumed on large commercial vessels but don't necessarily apply to us?

 

[pvb]

With the best will in the world, I very much doubt that thing is 130 dB

I have to agree, I doubt that any of these claimed dB figures are vaguely accurate. It's a bit like the lumens figures claimed in eBay ads for LED torches!

 

[awol]

Ebay for "Air horn" £9 for 150dB (claimed) Clicky

Or you could go for "La Cucaracha"

 

[AntarcticPilot]

Ebay for "Air horn" £9 for 150dB (claimed) Clicky

Or you could go for "La Cucaracha"

My Dad had Colonel Bogy on his!

 

[Refueler]

My Dad had Colonel Bogy on his!

I bought an air horn ... runs of air-cans as you buy for airbrush work .... from a chandler ! After about a year - I went to test it after it had been in its bag in the locker .... totally dead and useless ! Aircan was OK .. it was the horn !!

I keep thinking to replace it - but will go for a mouth operated blow horn next I think !

 

[awol]

Heading down the Clyde in thick fog getting close to Wemyss Bay/Rothesay ferry route, two fog horns sounding ahead. MVs Bute and Argyle have exactly the same tone of horn - not clever.

 

[AntarcticPilot]

I have to agree, I doubt that any of these claimed dB figures are vaguely accurate. It's a bit like the lumens figures claimed in eBay ads for LED torches!

dB is a ratio, so without stating the reference, it is meaningless.

 

[rogerthebodger]

Ebay for "Air horn" £9 for 150dB (claimed) Clicky

Or you could go for "La Cucaracha"

You will find that the compressor like those only last 5 minutes in a marine environment.

I have the bits to prove it.

 

[Roberto]

You will find that the compressor like those only last 5 minutes in a marine environment.

Possibly any environment.
I had one on my motorcycle 30+ year ago, the traitor let me down and became shamefully silent a few minutes after the beginning of street celebrations for a World Cup victory, I was left with just the flag, which then touched the exhaust and melted, releasing a thick smoke.