Paddlewheel log transducer alternative

[JAYEL]

Is there any solid state log transducer compatible with NASA instrument displays? or are they suseptible to fouling just as the run of the mill, excuse the play on words, paddlewheel log transducer.

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[Talbot]

There are EM transducers available, and these do solve the fouling problem.

However they do not fit all logs and are also very expensive

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[JAYEL]

Talbot, what do you mean by EM? and roughly how much is expensive? Regards Jayel.

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[aluijten]

I assume you've looked at:
http://www.echopilot.com/itemdets.asp?infopage=index&itemid=13&infoid=Ultrasonic

I have no experience with it myself, but you might give them a call, if this is news for you.
I'm not sure about pricing, I vaguely remember something like 400-500 EUR for the sailboat version (slow speeds).
I'm not sure if they can be hooked up to the NASA instrument, but if this instrument has a calibration function, my guess is that it shouln't be too problematic.

Arno

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[Talbot]

EM = Electro magnetic
for example the <A target="_blank" HREF=http://www.venteville.nl/kk_700007.html>the Sagem LH-92</A>

Havent been able to find it quickly with google, but a couple of years ago there was a small article in PBO about a company making the transducer only that was designed to interface with existing small craft logs. Cant remember the price.

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[Graham_Wright]

Brookes and Gatehouse were investigating a two pole ultrasonic transducer but I don't know if it ever reached production

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[FWB]

I have ST60 system. I originally had an Echopilot ultrasonic transducer but this never really worked properly with the ST60...it would start to wander off on its own from time to time. When I first had the ST60 system Raymarine didnt offer an ultrasonic tdxr but they do now and I have this and it works very well. Its not cheap but if you dont want to ever have to worry about tdxr fouling then I recommend the ST60 system.

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[simonfraser]

i tow mine from the bottom of my bridgedeck, it's a catamaran.
it is fixed through a bit of guttering with an apropriate bend in it, yes i know it sounds crazy, but works fine & i can clear it easily.
you have to fit it at the end, otherwise the guttering starts to ski on the water & then the reading is not accurate.
fit a bit of string at the rear end so you can pull it up to clear and pull it out when not sailing.
no it does not tip over & works up to at least 11 knots !


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[hightech]

Most "non-moving" paddle transducers are NMEA output devices. So if your instruments can accept an NMEA speed input then you could try the Airmar unit



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