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  Topic Review (Newest First)
07-08-2012 09:36 PM
Re: Depth sounders

Well now this gets complicated. I believe the vast majority of transducers are manufactured by Airmar. I got a generic Airmar p79 from a local marine electronics store.
AIRMAR Electronic Catalog
The P79 comes in two basic versions, a NMEA 2000 or a NMEA 0183.
My is15 instruments are connected through an AT15 to a Simnet bus which is basically a NMEA 2000 bus with different cable connectors so I got the NMEA 2000 version and plugged it into the bus.

You probably don't have the Simnet bus, so you would get the 0183 version and then plug the output into the NMEA 0183 jack on the back of your IS15 display head. When you turn off the IS15 depth sounder it will then display the depth data that is coming over the NMEA network from your new tranducer.

It is not a plug and play solution, but is not really too complicated if you have a grasp of the networking. You will need to do some wire splicing to get the output from the transducer into a plug that fits the jack on the back of the display unit and you will need to supply power to the transducer.

Here is a link to one site that sells the transducer.
NMEA 0183 P79 Transducer P79-235-0 | Blue Heron Marine Electronics
07-08-2012 08:45 PM
Re: Depth sounders

Was this an Simrad IS15 depth finder and if so where did you get the transducer.
07-08-2012 05:52 PM
Re: Depth sounders

I don't know if we have the same issue or not. Mine was erratic on when it worked or not particularly in shallow water. I finally concluded, right or wrong, that it was because the transducer was installed with way too much deadrise causing the usable signal to be very weak.

I installed a new shoot through the hull P79 smart transducer under the foot well under the chart table. It works like a charm and gives consistent readings up to six or seven hundred feet.
07-08-2012 05:13 PM
Re: Depth sounders

I have a IS15 depth sounder that seems to want to come on only after it has been turned on and off a couple of times. The folks who make the transducer says they either work or don't work and I probally have a cable issue. Has anyone else experienced this
03-09-2012 06:47 PM
Brent Swain
Re: Depth sounders

Carry a spare , when cruising the South Pacific. Mine screwed up down there and I had to sail home without one. Not so readily available down there, and super cheap up here.
03-09-2012 01:11 PM
Re: Depth sounders

Thanks, johnharch,
I think you're right. The PSC hull shape probably dictates the transducer placement. On other, flatter-hulled boats, it can go towards the bow. In any case, I agree: I really don't have to worry about its placement as our waters are plenty deep. Also, I've always thought that I'd have to be going forward VERY slowly for the "advance warning" of a forward-placed transducer to allow me to react in time to avoid a grounding.

Fair winds
03-09-2012 11:47 AM
Re: Depth sounders

Elena, I have come to the conclusion that on the 34, there is no ideal location and having talked to a lot of people, the is no normal location. If you're not concerned with shallow water performance, I don't think it matters much.

On the 34, any good forward location will have too much deadrise and I have concluded that that, coupled, maybe, with my transducer being old is my problem. I have about 27 deg deadrise where my transducer is now and I can find no thru-hull transducer that will work with that much other than the fairing models which then protrude below the hull a bit.

Putting the transducer forward has two advantages that I see, cleaner water when in the shallows and you see what is happening on the bottom a little sooner. But I don't like the idea of the fairing protruding. It just seem like something to get broken by a minor collision with a log or something.

I have been testing shoot thru the hull transducers and seem to get reasonable results aft around the galley areas, so I am going to install a P79 smart transducer somewhere around there.
03-09-2012 11:22 AM
Re: depth finder

Originally Posted by niftynickers View Post
My xducer was originally installed next to the raw water intake behind the keel okay if you are at sea or sail in deep water but not good for shallow water sailing.
Our transducer is located behind the keel, too. It seems like an odd choice to me, but there must have been a good reason for the original location choice, even if we decide sometime to move it. Can anyone shed some light on the thinking of this placement?
We sail in deeper depths so for the most part this transducer location has not been a problem.
02-22-2012 04:35 PM

My location for the xducer for the Humminbird on my 37 may be different than is possible on the 34. It is epoxied directly to the hull just in front of the keel and shoots thru the hull.Since we have solid glass boats (not cored) it's possible to do so.The hull is curved in that area so I had to grind a little and build up the epoxy to level the xducer.

Good luck,
Dianne and Chuck Burke S/V NiftyNickers C37 #139
02-21-2012 08:57 PM
johnharch Bill, it sounds like you have pretty much the same system and transducer location as me except that I have separate transducers for speed and depth. I regularly get depths to 300'and often to 400. But it's really frustrating when I'm looking for just the right place to drop the hook and the bottom is at 15' and rising and depth sounder goes out. I suppose it's possible that it happens in deeper water too and I'm just not paying as close attenetion to it, but I don't think so.

I'm not sure of my exact transducer model number, but I was just looking at the Airmar site and see that tranducers that look just like mine are internally compensated for various installation angles. So the angle probably isn't the problem.

Maybe I'll just replace the transducer insert and see what happens. Fixing this is on my priority project list for this winter.
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