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Full Version: Tacktick intermittent knotmeter malfunction
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After years of working properly my tacktick knotmeter is getting quirky. One day after working well, it abruptly started reading much lower speeds (say 0.6 knots down from 6. That reading then decayed to zero over a period of perhaps 10 minutes. Back at the mooring I pulled the triducer and spun the paddlewheel. It spun freely and gave a very low reading for a while and then went completely to zero. Depth and water temperature red correctly. The next time I used the boat everything was fine. Then several days of failure. Once or twice I could get a very low temporary reading by turning the instruments off for a few seconds and then back on. Finally yesterday it started out working properly for about 20 minutes and then decayed slowly from 6.3 knots down to zero over a period of about 10 minutes.

What should I test? Which replacement part should I consider?
Welcome to the Raymarine Forum beepbeep,

Based upon the symptoms reported, it is believed that there may be a fault with the system's Tacktick Hull Transmitter. It is accordingly recommended that the Hull Transmitter be sent to Raymarine’s Product Repair Center to be bench checked / serviced.
When removing the transmitter T121 i saw that the gray terminal on both the depth and compass plugs was not connected to anything. There was a one inch length of uninsulated wire to each of those terminals. I am sure that it has been that way since I bought the boat as a six year old in 2011. to what are these terminals usually connectedand what are the consequences of a disconnect?

The shield leads (bare wire) of the transducer cables should be connected to the corresponding grey posts of the of the hull transmitter. It may be worth making these connections and then testing the system prior to sending the hull transmitter to the Repair Center.
I did not really notice the ground wire problem until I had sent the transmitter to service. Service found the knotmeter to be OK, but the depth was giving readings of about 30 feet in their 10 ft. deep test tank. (Depth was behaving properly when I disconnected the transmitter). Service returned the transmitter without charge. while the transmitter was out, the apparent wind speed and direction were behaving OK, but at some point the analog display stopped reading data, although it powered up from the single digital display, which I always use to turn on the system.

My thought is that the intermittent knotmeter readings reflected a slow motion failure of a stranded wire ground.

I reinstalled the transmitter but the displays were now not receiving any data from the triducer, i.e. the display showed dashes rather than 0 for knotmeter and proper numerical readings for depth and water temperature. The apparent wind speed and direction continued to display correctly on the digital display and dual digital display for perhaps a week. but then they also stopped receiving a signal. I went through the autonetwork but the problem remained. All three displays power up when one is turned on. I did the autonetwork with the displays close to the hull transmitter but did not get the wind transmitter/transducer off the top of the mast.

In reading the installation leaflet for the hull transmitter, I noticed that it should be mounted at least 50 cm. above the water line. Mine is mounted at the water line, although that had not given any problems for 11 years.

The recommendation regarding the mounting height above the waterline for the hull transmitter is to maximize wireless communications between the hull transmitter and the other components of the TackTick system. Given the symptoms and no past history, it would have been recommended that both the hull transmitter and transducer both be sent to Raymarine’s Product Repair Center to be bench checked / serviced. However, given the past history of the product, testing, and current symptoms, it is recommended that the hull transmitter alone be sent to Raymarine’s Product Repair Center to be bench checked / serviced. That said, should it be easy enough to remove the transducer, sending both components would allow them to be tested as a system.
Hi.. I've having pretty much the identical problem here. And, as a result of reading the recommended therapy, I purchased a brand new T911 Hull Speed transducer with the same results. Then I purchased a brand new T121 Hull Transmitter. The Hull transmitter is also connected to a Tacktick compass (which works and displays fine) BUT.. Speed when plugged into the boat rarely displays anything above 1 knot. When I test the T911 by either spinning or blowing on the wheel it only produces a speed when the wheel is spinning extraordinarily fast. Meaning I'm blowing on it full blast to produce any speed at all. After purchasing 2 brand new instruments to get the same result as before with the old.

Display is a T111. Using the display I've confirmed all normal settings for speed are as they should be. My current challenge is I need correct speed display for a regatta this coming weekend. Any help would be appreciated.
Welcome to the Raymarine Forum Andy,

We're sorry to learn of the reported issue with your TackTick system. Should one of these components not be faulty, then rapid rotation of the transducer's paddlewheel should result in speed readings over 1kt. In this case, the fault may be rooted within either component. Should a customer be uncertain about whether their is a problem with the hull transmitter or a transducer, then it would typically be recommended that the hull transmitter be sent to Raymarine’s Product Repair Center to be bench checked / serviced and to avoid potentially replacing the incorrect item. Should the hull transmitter be found to function correctly through a range of speeds by the Repair Center, then it would be advised that the transducer be replaced. Should it be convenient to do so, then the transducer should be sent to the Repair Center along with the hull transmitter. As you have indicated that you have replaced both the hull transmitter and transducer, it is recommended that the hull transmitter be sent to Raymarine’s Product Repair Center to be bench checked / serviced.
Both of these units are brand new.

I do indeed understand that both products are new ... yet there unfortunately is a fault with at least one of them. As indicated within my prior response, these devices may be sent to the Product Repair Center to permit the faulty component(s) to be identified and replaced. If purchased within the last 30 days, you may also want to consider returning them to your Raymarine dealer for replacement.
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