Installing a transponder

Jul 30, 2013
56
Hughes 25 Burlington
I've seen a few ways to do this but can you give me any suggestions on something that's fairly easy and has worked for you.
 
May 24, 2004
7,213
CC 30 South Florida
What kind of a transponder? It could vary whether for a depth instrument or an AIS vessel identification signal.
 
Dec 11, 2010
486
MacGregor 26x Hayden AL
I stuck mine down inside the hull. That is about as easy as it gets. Works great and even gives me a water temperature. I don't know how accurate the water temp is, but I believe it is close. All wiring is inside the boat...no holes.
 
Oct 24, 2010
2,405
Hunter 30 Everett, WA
I stuck one down with bees wax (toilet ring material $2) as a temporary mount and never changed it. The idea was to experiment to find a good location. It's still working after 6 years. It's also in an out of the way location (inside a cabinet under a drawer.)
 
May 17, 2004
6,152
Beneteau Oceanis 37 Havre de Grace
We stuck what was designed as a transom mount transducer inside the hull in silicone. Worked perfectly for depth and bottom contours. Temperature was generally within a couple degrees of what was reported by a nearby weather buoy.
 
Dec 25, 2000
6,052
Hunter Passage 42 Shelter Bay, WA
Depth Transponder

A couple more questions.

What will the transponder connect to, a display of sorts?
If a display, where will you locate it?

The best place for a depth transponder is forward of your keel so that you receive an earlier warning of shallower water.

I have two on our boat, the original through hull forward of the keel and a second shoot through the hull next to the shaft strut that connects to the Garmin 178C Sounder that I installed several years ago.

Both give me plenty of good information until the two signal cones intersect at about 250 feet. I made a shallow dam out of painters tape and filled it with a tube of clear silicone then placed the transponder into the goo. I filled it with water first to make sure the Garmin was receiving a clear signal from the transponder. It needs to shoot through solid FRP absent any voids.

That was over ten years ago and the system still works great. Fish finder, water temperature, oh and water depth.

Hope this helps.
 
Mar 1, 2012
2,182
1961 Rhodes Meridian 25 Texas coast
"The best place for a depth transponder is forward of your keel so that you receive an earlier warning of shallower water."

Yeah right..five knot boat ten foot difference- you can't react that fast.In the real world, makes absolutely no difference, unless you are on a 100 foot+ boat.
 
May 17, 2004
6,152
Beneteau Oceanis 37 Havre de Grace
"The best place for a depth transponder is forward of your keel so that you receive an earlier warning of shallower water." Yeah right..five knot boat ten foot difference- you can't react that fast.In the real world, makes absolutely no difference, unless you are on a 100 foot+ boat.
Agreed. Let's assume you have a 30' boat and are able to mount the transducer 10' in front of the keel. Let's also assume that you know you're in a dangerous area and keep your speed to 2 kts (3.4 feet per second). This means that from the time when you see a shallow depth reported, you have less than 3 seconds to take evasive action. This even assumes that you don't have any delay from the time when the sensor sees the shallow water until the time when it is reported on the display. If your speed is 4 knots you have only about a second to turn away from the shallows.
 
Apr 24, 2006
868
Aloha 32 Toronto, Lake Ontario
We stuck what was designed as a transom mount transducer inside the hull in silicone. Worked perfectly for depth and bottom contours. Temperature was generally within a couple degrees of what was reported by a nearby weather buoy.
Does the temp work that well? I used a "well" of 4 inch PVC pipe with the transducer mounted in the cap. Filled with water, the transducer head almost touches the hull.
The temp is nowhere close but maybe if it was epoxied to the hull? Now I'm curious. I never expected the temp to work but would be nice if it did.

Chris
 
Jul 30, 2013
56
Hughes 25 Burlington
Greg,
I went thru your site and read the instructions but now tell me why you did it this way, please.
 
Jan 22, 2008
551
NorSea 27 Az., Doing the To-Do list
Greg,
I went thru your site and read the instructions but now tell me why you did it this way, please.
Sunday,

I wanted to put the transducer INSIDE the hull with NO holes. I was at a home store and found the PVC parts for low $$. I just thought it was a good way to go.

If you look one page up on the web site ( http://www.svguenevere.com/prep/proj/ ), you will see that I installed it in 1993. I have not touched it since, and it's STILL working just fine. :D

I may be different, but I never did use it for water temp. ;) I just drop a pool thermometer on a string over the side if i think I "need" to know the water temp. Oh wait, I now have one of the low cost no-contact ones from Harbor Freight. ;);)

Good luck on what ever way you decide to go.

Greg
 
Jan 22, 2008
551
NorSea 27 Az., Doing the To-Do list
Just wondering, though, why you put it in mineral oil. :confused:
Ohhh... :doh:

Mineral oil does not evaporate and/or foam when shaken up. It's thicker than water and low cost. Also, it will not grow green stuff over times.

As I said, since 1993 I have not had to add more oil or do anything to the setup. It's still working as it did when I first installed it.

Also, I did it that way instead of potting or setting it in resin so that when the time comes to put a new transducer in, I can just change the top if it's not an exact fit. OR, remove it completely if needed.

Greg