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  1. #281
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    If you use epoxy that sets hard the energy from the transducer could shatter it over time. Interestingly, I had a chat with one of the commercial unit suppliers at LIBS, and he said that their transducers are encapsulated inside an outer casing made of glass reinforced plastic, as they think that the transducer will eventually shatter a plastic pipe fitting as used in the Jaycar kit. Time will tell, but if it does shatter I will simply use epoxy adhesive to stick the transducers to the hull.
    Working on immortality - One day at a time.

  2. #282
    nigelmercier's Avatar
    nigelmercier is online now Registered User
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    Quote Originally Posted by Plamen View Post
    But do you agree, harder epoxy resin would also electrically protect, but help the ultrasonic energy to better penetrate the hull??
    I don't think it makes any difference, as the transducer is almost in contact with the hull. I've got a similar transducer in an ultrasonic cleaner, it just sits on a bit of flimsy plastic.
    Nigel
    FREE Bavaria Yacht Forum: www.bavariayacht.info

  3. #283
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    Location : Me - Derby Boat - Greece
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    Default I had to laugh

    Quote Originally Posted by nigelmercier View Post
    Looks like we have someone from Jaycar on the forum now, great stuff. Perhaps he can sort out the nonsense that causes the pack of epoxy to take the weight of the kit into the next delivery band ...
    Just received my kit(s) and quickly built one of them.

    So how do I know the bloomin thing's working ?
    I have slight hearing loss at the top end so cant hear these clicks that have been mentioned. I also dont have a sillyscope, but Id like to know its working before flying it out to the boat.

    The thing that made me laugh was following Nigels comments about the carriage costs for the epoxy, I looked at mine and saw "made in Ashby De la Zouch". 40 miles round trip from my house or 20,544 miles via Jaycar

  4. #284
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    Default Mounting the transducer

    I've been thinking about this part of the assembly. Jay car has made a great job of putting the kit together and pretty good with the instructions. The mounting is a variable out of Jaycar's control. Obviously we all want to get the maximum value out of the unit and the best way is to get the transducer mounted directly on to a solid part of the hull where the vibrations will resonate through the entire length of the hull. Any interface between the transducer and the hull's outer laminate absorbs energy and reduces the effectiveness of the anti fouling.
    The question to be answered is, what is the life expectancy of the transducer. I reckon it is probably at least 15 years. So mounting the unit directly onto a prepared area on the inside of the hull outer shell using the same material l as the hull I.e. GRP epoxy resin will give the best conduction. Sliding a sleeve made from thick flexible pipe over the unit and back filling to pot it will use minimal space and provide a vibration resistant outer jacket. Fit and forget for at least 15 years, and then cut it out and replace it if it fails.

  5. #285
    Plamen is offline Registered User
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    Basically, you are right.
    Permanent GRP “pouring-in-place” would be the best for a flat & easy accessible mounting location.
    On a place with significant declination, or hard-to-access, could get difficult.

  6. #286
    Plamen is offline Registered User
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    Quote Originally Posted by affinite View Post
    Just received my kit(s) and quickly built one of them.

    So how do I know the bloomin thing's working ?....
    Put it 1/3 in water and you can observe the surface vibrating.
    Strong light source to the water surface, play changing the light angle,
    and you can see decent waves.

  7. #287
    nigelmercier's Avatar
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    Quote Originally Posted by Stefanb104 View Post
    The question to be answered is, what is the life expectancy of the transducer. I reckon it is probably at least 15 years...
    I wouldn't like to put a value on the MTBF, but I do know that the specification of the driver is well within the ratings for the device. Even if it is mounted directly (as I intend to do) there should be no problem prising it off.
    Nigel
    FREE Bavaria Yacht Forum: www.bavariayacht.info

  8. #288
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    Sep 2011
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    Default Mounting the transducer

    Well, so far it seems that mounting the transducer directly is becoming favourite.
    The only piece of the jigsaw that is missing is the manufacturer's spec on the expected service life of the unit.
    Can anyone track that info down? I wouldn't know where to start.

  9. #289
    nigelmercier's Avatar
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    Quote Originally Posted by Stefanb104 View Post
    The only piece of the jigsaw that is missing is the manufacturer's spec on the expected service life of the unit...
    I've emailed the manufacturer.
    Nigel
    FREE Bavaria Yacht Forum: www.bavariayacht.info

  10. #290
    affinite's Avatar
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    Default Spectrum Analyzer

    I thought the members of the JUAF club might like this little piece of Freeware at

    http://www.sillanumsoft.org/

    Its a PC based spectrum anaylzer. I havent really got much of a clue how to use it but when installed and hooked up to a simple microphone is does show all sorts of interesting waveforms comming from the transducer.
    I was suprised to see no signals above 20kHz but perhaps its because I was using a very basic/cheap microphone and 40Khz is above its operating range.

    Anyway, seeing the waveform dancing around on my "scope" along with my ringing ears are good enough for me to assume Ive built the kit(s) correctly.
    Just hope the barnies agree

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