Speedometer question?
posted 03-26-2002 02:59 PM
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Can someone tell me the Pro's and Con's of a Pitot tube and a Paddle wheel? Does one work better in certain situations? Thanks.
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There's a reason they call it fishing and not catching, but I don't have to like the reason!
Here fishy fishy :smile:
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Posts: 80 | From: Mount Angel, Oregon | Registered: Sep 2001 | IP: Logged
NorRivDave
Chromer
Member # 631
posted 03-26-2002 03:05 PM
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I think the wheel works better at slower speeds, but both need to calibrated with a gps for accurate measurements of speed.
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I have an eye problem...I can't see being here at work any longer.
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Posts: 156 | From: Hillsboro, OR 97123 | Registered: Dec 2000 | IP: Logged
Pilar
Ifish Forum Guide
Member # 270
posted 03-26-2002 03:06 PM
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Pitot tube is a mechanical gage and uses pressure from water flow to move the gage, showing you your speed. These work ok and are inexpensive but are worthless at less than about 10mph.
Paddle wheel is a magnet that spins and drives an electronic indicator on your gps or a dash meter. More expensive by far and also more accurate at low speeds. Mine works down to 2 mph and sometimes even slower.
I use both. Just part of the redundancy thing on a seaworthy boat. Two of everything means at least one of anything is working all the time.
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The bend is your friend!
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Posts: 1657 | From: Portland, Or., U.S.A | Registered: Aug 2000 | IP: Logged
ampersat
Chromer
Member # 727
posted 03-26-2002 03:11 PM
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i have a cheapo gps (which is a relative term, really - none of them are that cheap). anyway, my bottom-of-the-line gps will tell me how fast i'm going. with this in mind, why would you need another method for determining speed? the only thing that comes to mind is maybe you care how fast you're going in relation to the water (ie, trolling speed).
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"it's alright little brother, there are more!"
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Posts: 277 | From: tigard | Registered: Jan 2001 | IP: Logged
Silver Hilton
Fry
Member # 2322
posted 03-26-2002 03:12 PM
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Ah, Pilar, you must consider the old saying - a man with one watch knows what time it is. A man with two watches is never sure.
In all seriousness, I have used the paddle wheel jobbies that come with my depth finders (by Eagle) for years and have ben pretty happy with them. They have a tendency to get gummed up by algae and salt water, which causes them to work poorly at slow speeds until you clean them. I clean mine with a spraying from a fresh water hose, which keeps it working pretty well. Mine tends to work pretty well down to the slowest trolling speed I can muster, which is around .7 mph.
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I fish, therefore I am.
I am, therefore I fish.
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Posts: 6 | Registered: Mar 2002 | IP: Logged
Floater
Chromer
Member # 1494
posted 03-26-2002 03:18 PM
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Good info, thanks. My boat does not have a speedo but I'd like to add one. I'm looking at those that top out at 50-60mph. I'd also like to add a trolling speedo that shows between 0-5mph. The trolling speedo uses a paddle and most high speed gauges use a pitot. But, I found ONE that shows 0-50mph really well but it uses a paddle wheel. Any ideas?
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There's a reason they call it fishing and not catching, but I don't have to like the reason!
Here fishy fishy :smile:
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Posts: 80 | From: Mount Angel, Oregon | Registered: Sep 2001 | IP: Logged
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