Harry & Nancy, This past August I re-visited the depth sounder/fish finder installation on our M17. As you mentioned, my goal was to not drill a hole in the hull and still get good depth reading. My first attempt (beta 1.0) was using an Eagle Cuda 242. with this unit I had mostly-reliable reading securing the transducer to the hull in a couple of places. Oddly enough the depth readings were unreliable in water shallower than 15ft. Not fully satisfied with my beta 1.0 results, this past August I found a store with a good return policy and after much research purchased a Garmin Fishfinder 140 (displays depth, battery voltage, and water temp.). I'm very happy with the beta 2.0 results! Good reading is both shallow and deep water. And very good detail of the bottom contour. The Transducer location that gave the best performance on our 1988 model M17 is the cavity area just aft of the keel (the place Tom Smith calls the wine cellar). In their I placed the transducer, and for A+++ performance added a couple of inches of water submersing the transducer. The 2nd best location, which may work well on the M15, is the flat area in the middle of the hull just aft of the keel. This is the flat area which eventually forms the skeg. I sanded off the interior gelcoat and using some silly putty as a temp. adhesive also had very good results there. My conclusion is that good thru-hull depth performance is first a function of the vendors transducer, and secondly a function of location. Early on I was convinced performance was a function of a dual-frequency transducer versus a single-frequency transducer, having seen the single-frequency Hummingbird unit perform very well on Larry Yakes boat, easily reading to 300+ feet. If anyone is looking for an exceptional deal on a used Eagle Cuda 242 please email me off list! Merry Christmas to Everyone, Randy Graves M17 #410 On Fri, Dec 11, 2009 at 1:09 PM, Harry & Nancy <nanarry@shaw.ca> wrote:
Hi folks: Re M15 and installing a fish-finder. I've tried to find some info. on our site and the most reassuring( to me, that means no hole in hull) is from Randy Graves posted Dec.27/08. Of particular interest is location of the sensor.Randy, if you or anyone else has tried placement aft of the centreboard,I'd much appreciate learning of your success. As I discovered this past summer on L. Superior, rocks and "Li'l Nan" don't mix! _______________________________________________ http://mailman.xmission.com/cgi-bin/mailman/listinfo/montgomery_boats
Remember, there is no privacy on the Internet!