Airmar (Raytheon?) transducers in 23.5

[Matt Nelson]

I recently purchased a 1993 H23.5. I has an ST50 tridata and I believe Airmar transducers, but I am not sure. I think that they were factory installed, but am not sure because I am the 3rd owner, and the 2nd owner didn't know. Were the Airmar transducers packaged with the ST50 by Autohelm/Raytheon? What model transducers might I have? I know that the speed transducer is mounted aft of the ballast tank slightly off center. Can I remove the transducer while the boat is in the water? Is the depth transducer and the speed transducer the same unit? There is a wire running from the st50 forward into a sealed compartment in the bow, however there is no transducer visible outside the boat on the underside of the hull? What might this wire be for? I haven't opened up the sealed compartment and hesitate to do so. (If any other h23.5 owners read this and know what is in this front compartment, please let me know.)Are there any special calibration procedures that need to be followed for these transducers or the ST50?Thanks for you help!Matt

 

[Bill Boudreau]

Z091, Z092 or Z092P, and E26012

I do not know the particulars of the boat and there are several configurations the transducers could be installed in depending on the purchaser and the installer. The ST50 Tridata was packed with a lexan low profile speed Tx and a lexan low profile depth Tx. It was also sold as the display only and could have been installed with a bronze triducer (e26012 or Z093) that had both the depth and speed functions. Airmar manufactures all the transducers for our depth and speed instruments. They also manufacturer a wide range of transducers for most other marine electronics manufactuers.In 1993 the Z092 transducer was changed to the Z092P. Both of these speed transducers had paddle wheels that you can see from the bottom of the boat. You can also remove the Speed Insert from both of these housings. The Z092 did not have a self-sealing flapper and has 6 paddles on the wheel. The Z092P had a self-sealing flapper and 4 paddles on the wheel.It sounds like someone has installed an In-Hull transducer in the forward "unidentified" compartment. This could be a transducer specifically manufactured for this or one of the Z091 transducers epoxied into the hull. It is possible to shoot a transducer through the hull if the hull construction is less than 1" thick solid fiberglass layup, without any voids or coring in the construction. One of these installations will not work properly if there is any air in front of the face of the transducer. It sounds like someone has built a housing, and filled it with mineral oil and mounted a transducer inside this housing.You must have a speed paddle wheel coming off the bottom of the boat if you are getting speed-readings.I hope this helps!