Low water alarm for boat

Louie, any over the counter depth sounder/fishfinder will have a shallowwater alarm in its program.Then its up to you how you install the transducer.

regards Keith C

Most (if not all) FF's have low water alarms, all FF's have a choice of thru-hull or transom mount transducers.

I have the cheapest garmin on the market (F80), cost about $150. It has an adjustable visual and audible low water alarm.

Thanks for the suggestions but I'm not after a fish finder. I just want a dedicated shallow water alarm for my ski boat. I know Navman make one but I cant find any info on it. I believe it doesn't come with the transducer - an extra.

Crikey Doug,
You Terrry Torians could become more of a problem than cane toads.
Flamin crow-eaters! Sheesh!!
Seems I'd best give Dusty a call, eh; keep the ole feller on slim rations.
Till later Doug.
JnJ

Louie the only one I can find is the Navman FISH FINDER. Does what you are asking but it is still classed as a fish finder.

Running my old Quintrex with a hummingbird (entry level) fish finder they were only good at low speed.

At high speed the airation under the hull disrupts the signal and it a jumble. I found that the use of the low water level was only appropriate at low speed and believe that is not effective for your use as a skiboat.

Maybe the tri band (three signals one back one forward and the usual one down) ones are more suitable but the price relative.

Navman

Matt.

Louie,

You don't need to purchase a specific transducer to "shoot" through the hull. Prior manufacturers designing transducers specially for transom mounting it was up to the purchaser to decide how they wished to go about the exercise.

Transom Mount:
Fabricate your own bracket to support the transducer over the side of the boat. Most were stern mounted however it was not unusual to for some to be suspended over the side of the boat or even over the bow.

Through the hull:
Fabricate a "well" in the bilge into which the transducer was mounted, this involved a hit and miss guess as to the correct mounting angle. The well was then filled with pure silicon, very expensive, or light mineral oil and sealed off.

I have seen through hull transducers shooting through both fibre glass and aluminium hulls. The alloy boat I saw was an early 17' Quintrex running out of Batemans Bay.

The common factor with all these vessels was that no one expected any readings at any more than a fast idle.

The first thing that kills of a sounder reading are the microscopic air bubbles being drawn through under the hull.

I've spent an enormous amount of time adjusting transducer heights and angles so as the get readable results at the highest possible speeds. I would also claim to have achieved above average results. These results however are no where near the speeds required to tow a basic water skier and certainly not near that required to satisfy na above averge skier.

Not wishing to chuck cold water on your exercise, however I really believe that you will be very disappointed in the result after spending your money.

Ian


Ian

Thanks for all the replies (yep, even yours Doug)... After speaking to a guy today with a high end wakeboarding boat that has a factory fitted job, he's confirmed that it is a WOFTAM at anything over about 15 kph, which goes without saying really. I suppose I will just keep a keen eye out for shallow water and put the money saved towards beer and prawns.

I might try the stick method though.

A water depth monitor is a sonar. A fish finder is a sonar. Same dog, different name. A small FF can be programed to just show a digital depth reading (with alarm). You don't have to have the picture of the fish/bottom/thermoclynes (sp)...........

Whitworths stock a Raymarine ST40 depth guage. Not real cheap at $299 but comes with transducer.

Part number 47170N might be worth contacting them for more info?

Peter

Most depth sounders only tell you why you ran aground, in the situation you describe you really need a "forward looking" sonar.SEE HERE