Depth and speed transponders on long keel hull

DoubleEnder

DoubleEnder

Well-Known Member
Joined
27 Apr 2002
Messages
1,546
Location
N Hemisphere
Visit site
I'd be interested to hear what make and model of transducers forumites have fitted . My boat is a W Fife designed 34' sloop, carvel mahogany on oak, planks 7/8" thick. Its a long keel, with a lot of deadrise, so its not possible to find a place where the echosounder will point directly at the bottom - even with an angled hole in the boat.

I was all set to use the TackTick gear. I like the idea of fewer wires, but am reconsidering due to the dimensions of the transponder. What I really want is a transponder that has a lot of length, and a small surface area, so I can make the through-hull hole at a decent angle and not need a huge fairing piece. If you see what I mean.

Anyone got any good ideas? What do the Twisters use - that must be a similar set up?

Many thanks

Graham
 
Joliette also has 7/8" planking and has Autohelm (now Raymarine) transducers fitted. These have plastic through hull fittings, rather than bronze, which is recommended for wooden boats. Theory being that water absorbing planking will expand and crack plastic fittings .... However, you can save the cost of bronze by drilling a slightly larger hole than recommended for your plastic through hull fitting and using a suitable sealant.
 
28 foot carvel cutter, bronze Raymarine (Airmar) transducer (log and depth) set in fairing block, tapered fore and aft, through 1.25 inch iroko hull, with internal fairing block. Overall, because of a very curvaceous hull, a reasonably serious bit of work was required to produce a horizonal level for the transducer. This is the second baoat that I have had with a similar installation, both have worked well.
 
I had a depth sounder which had the transducer mounted in a wooden block on one end of a longish tube, which carried the cable to the readout unit. This could be held over the side to 'see' the depth anywhere around the boat. This was particularly valuable when coming alongside a wharf, or anchoring in an unfamiliar anchorage. The other benefit was no hole through the bottom of the ship.
Peter.
 
I installed an airmar bronze transducer on my (wooden) Twister; from memory, I think the stem was about 6" long. Inside I used the supplied resin fairing block with an appropriate cut across it. Outside, I made a large fairing piece out of oak. Definitely worth getting the transducer vertical, for all the obvious reasons.
 
The NASA Clipper echo sounders still use the narrow stem (about 14mm dia) and small head unit. It looks a bit like a microphone. This only makes a small hole through the planking. If you are careful, the faring chock can be the size of a pear anode, which I think is acceptable.
Incidentally, these transducers will also run the old seafarer rotating LED style of head units, which many find they prefer, after the modern LCD "random number generators" have driven them (OK, ME !) Mad !!
 
Random number generator

We recently changed for an old seafarer to a NASA digital unit because the display is smaller and we could reuse the transducer. We are now wondering whether to change back as the random numbers and occasional 'outs' drive us mad.

Does anyone have any tips for reducing the random numbers? Are the modern Airmar transducers better? Is it the mud (we are on the East coast)?
 
Re: Random number generator

I'm not sure if my transducer is extra long; it came as a standard option (if that makes sense!) with the echo sounder which is a raymarine ST40.
 
You must log in or register to reply here.

Share this page

Top