Randy, I have an M-15 and have played with the location of the transducer with little success. The ideal location would have been in the forward hatch just forward of the ballast bubble. This location did not work for me, nor did any other location within the hull. The only reliable location was outside of hull. I created a quick mount using some 1/2 pvc pipe and ran the transducer wire through the pipe and back to the cockpit. I mounted the pvc pipe to the bow via the bow eye (used to attached the bow to the winch). This was a quick and dirty mount just to determine the functionality of the unit since the thru hull option did not appear to be working. My unit is a simple Hawkeye unit that numerically displays the depth. I am guessing the transducer is not powerful enough to shoot thru the hull. My only use for the unit is to tell me when the water is getting to shallow. I will be spending time this winter pondering how to mount the unit externally without drilling holes or having wires running everywhere. Any thoughts would be appreciated. Is silly putty a better mounting solution then silicone? Thanks, Skip Campion M-15 #208 -----Original Message----- From: R.K.Graves <rkgraves@gmail.com> To: For and about Montgomery Sailboats <montgomery_boats@mailman.xmission.com> Sent: Mon, Dec 14, 2009 2:21 pm Subject: Re: M_Boats: Transducer/fishfinder/depth sounder Harry, Sounds COLD in Thunder Bay Brrrr! I think a person can get the full enefit of the depth sounder without having to mount the transducer utside or through the hull. For a more forwarding-looking signal I hink the location Gary Hyde described would do the trick! I believe he location Bob described is roughly the same place as well. There is n alternate suitable location on the M17 under the v-berth, roughly t where your knees would be from the bow and I am guessing the M15 ould have roughly the same location. It is where the curve of the bow ransitions into the bottom of the hull. The fiberglass is thicker in his area but I was able to get suitable and consistent forward ooking depth reading, but not as good of a bottom contour reading. Some things to think about when considering transducer location vs isplayed information. The signal angle from the transducer is quite arge allowing you to see a larger area under the boat than you might t first think, depending on water depth. The update speed of the harted display may or may not be useful in seeing underwater bstacles while motoring or sailing. Both units I tested determine ater depth from the return signal directly under the transducer. hile sailing I found the numeric depth display the most useful nformation. When anchoring I found the display of the bottom contour nd depth the most useful. Displaying of battery voltage and water emp are just an added plus! My thought is to use a glob of silly putting and play with sticking he transducer to different locations inside the hull and see what erformance you get before opting for a thru-hull or exterior ransducer installation. Merry Christmas, andy Graves 17 #410 On Mon, Dec 14, 2009 at 7:20 AM, Harry & Nancy <nanarry@shaw.ca> wrote: Randy: Thanks very much for your prompt reply regarding placement of the ransducer.Do you know if threading the cable could be done through the same ole that the line to the swing centre board occupies. If so, then I could mount he transducer farther forward on the outer side of the hull,to enable a more dvance warning of rocks- a foreword-looking sonar beam. Also, I think I'll buy he Garmin unit.Thanks again, Randy, and also to others who helped. Not to be ut done by our good Yankee friends,since Dec.1,the temp. has hovered between 4F and -10F. All the best! Harry Elmslie,Thunder Bay,Ont. _______________________________________________ http://mailman.xmission.com/cgi-bin/mailman/listinfo/montgomery_boats Remember, there is no privacy on the Internet! _______________________________________________ ttp://mailman.xmission.com/cgi-bin/mailman/listinfo/montgomery_boats Remember, there is no privacy on the Internet!