Two depth sounders

F

FairweatherDave

Well-Known Member
Joined
28 Sep 2009
Messages
2,089
Location
Solent
Visit site
I am still learning some basics about our boat. I am guessing this is an depth sounder mounted on the inside of the hull (using a column of oil?).........

960x640_bestfit-2.jpg


and I am guessing this is also a depth sounder transducer fitting on my boat.......(ignore the hosepipe and bit of plumbing)

960x640_bestfit.jpg


Would appreciate confirmation of my guess work :). I am thinking the older fitting has simply been left there but I have not traced the wiring back and I only have one display for depth. I know the paddlewheel log is located elsewhere.
 
I'm sure that the second with the electrical connection is a depth sounder.

Has the first one got an electrical connection? If it hasn't then I don't understand how it works. What does the reinforced pipe connect to?

Richard
 
RichardS said:
I'm sure that the second with the electrical connection is a depth sounder.

Has the first one got an electrical connection? If it hasn't then I don't understand how it works. What does the reinforced pipe connect to?

Richard
Click to expand...
The reinforced pipe is purely physical protection for an electrical cable inside it. It has a slit down the side to allow you to remove it.
 
fergie_mac66 said:
Is that a cut hole in the hull that the fitting is put through
Click to expand...
No. The square hole is purely a hole in the locker floor (which is basically ply with a bit of fibreglass over). Inside that hole is the mystery square shaped item with dome shape which is what I think is the old depth guage (boat is a 79 Westerly).
 
FairweatherDave said:
No. The square hole is purely a hole in the locker floor (which is basically ply with a bit of fibreglass over). Inside that hole is the mystery square shaped item with dome shape which is what I think is the old depth guage (boat is a 79 Westerly).
Click to expand...

Just a guess, but is it an early attempt at ultrasonic antifouling? It was around in the 70s...
 
James_Calvert said:
Just a guess, but is it an early attempt at ultrasonic antifouling? It was around in the 70s...
Click to expand...
Well maybe, but there is no mention in all the old paperwork. I must admit I thought someone would pretty quickly come along and say that it is a hull mounted (not through hull) transducer that has simply been left there because the access to remove it is too awkward. Apart from depth transducers and logs what else gets stuck on the inside of a hull. (There is no anode on the outside but I don't remember seeing anything else when I AF-ed.)
 
FairweatherDave said:
I am still learning some basics about our boat. I am guessing this is an depth sounder mounted on the inside of the hull (using a column of oil?).........

960x640_bestfit-2.jpg


Bottom photo-transducer for depth finder. It looks like the cable outer vinyl sheath is split-possibly from stepping on it.
Suggest you seal the split with Sika,4200,Liquid Tape,etc. to prevent moisture from corroding the braid. Build a simple plywood box to sit over it if it's located where it can be stepped on or otherwise abused.
Just a guess on upper photo: Inside-hull depth transducer with hose for physical protection of wire.

Cheers/Len

and I am guessing this is also a depth sounder transducer fitting on my boat.......(ignore the hosepipe and bit of plumbing)

960x640_bestfit.jpg


Would appreciate confirmation of my guess work :). I am thinking the older fitting has simply been left there but I have not traced the wiring back and I only have one display for depth. I know the paddlewheel log is located elsewhere.
Click to expand...
 
Which locker is the top one in?

I have a VDO speed/distance log mounted in the engine bay on the port side. The drive cable runs in a tube up to the readout in the middle of the cockpit coaming at the back of the boat. The cable is rusted solid so the log doesn't work.

My depth sounder transducer is below the ice box next to the toilet seacocks.
 
Thanks Len and Bob. Len I will inspect the cable to the one we are sure is the depth transducer, it does look split. The other "square-ish" thingy is mounted forward of the port keel bolts but a bit more centre line, (perhaps 18" off). The paddlewheel log (not photographed) is mounted on the midline of the boat directly under the saloon table. I will do more tracing of wires in due course (there is no urgency here, just a sense of mystery.....)
 
I know you state that there is only one display, but don't bother trying to resurrect the old square device. Two echo sounders cannot work on the same boat, the echo from one confuses the other. I know,cos I tried. Our old sounder was starting to suffer from condensation at each end of the season, so I tried a NASA with an in hull transducer. To make the latter work I had to dismantle the hatch garage and get to the back of the original sounder to disconnect it from the supply to the other instruments.
 
Thanks John. That is what is behind this thread. My depth display is a bit dubious at times and I was thinking of just replacing the display. To do that you need to know about the transducer "output"..... that's when I twigged I had two:). It is just a little strange they seem both wired in.
 
I've had a navman fishfinder running alongside a clipper depth with no confusion between the two, both using nasa transducers, one glassed in, the other hanging in the bilgewater under the engine...
 
Ardenfour said:
I've had a navman fishfinder running alongside a clipper depth with no confusion between the two, both using nasa transducers, one glassed in, the other hanging in the bilgewater under the engine...
Click to expand...

Mine was a Navman 3100 depth and a NASA depth and I assure you that either would work, but not both. On reflection this may be because the transducers are fairly close together, how far apart they need to be you won't find in any owner's manual.
 
johnphilip said:
Mine was a Navman 3100 depth and a NASA depth and I assure you that either would work, but not both. On reflection this may be because the transducers are fairly close together, how far apart they need to be you won't find in any owner's manual.
Click to expand...

As far as reasonably possible and on opposite sides of the keel. About 3 metres, routine for me. One has a 1kW output, the other 600W. Mind you, if needed, fishfinders have interference rejection.
 
Interference between depthfinders/fishfinders is usually because both tx/rx on the same frequency. eg: 200KHZ.
Check your owners manual specs. for freq. of your unit(s).
If they are two different freqs,normally you should have no interference. Power output in Watts or distance between t-ducers,if different freqs, is not usually a factor. There are many dual. freq. units that use a single housing to contain piezo elements for both freqs.
Note: a broken braided sheath in a t-ducer cable can allow the RF signal to "escape" and cause interference to various eqpt.

Cheers/ Len
 
You must log in or register to reply here.

Other threads that may be of interest

Y
The Seafarer 700 and NASA clipper sounders saga
Replies
10
Views
430
Dellquay13
Dellquay13

Share this page

Top