Depth/speed sensor options.

[GILow]

Hi all,

The new boat came with exactly nothing in the way of working electronic instruments. In a way, this is liberating as it allows me to start from scratch rather than trying to choose compatible bits.

My preferred option at this stage is to avoid the mainstream stuff all together and go for generic senders that I can then build my own instruments to display.the data.

(Early development results are good, hooray for the ESP32 and all of its functional extra goodies. )

However, I had assumed I would install a triducer, something like the Airmar DST800 or 810, but I’m seeing a lot of people having problems with both.

Given I just want depth and speed (temperature, angle of heel etc don’t really feature in my wish list.) is there a better approach?

Maybe separate units? A through-hull sonar perhaps? (The fewer holes in the bottom of the boat the better, in my view, but I haven’t looked into the reputation of those depth sensors yet.)

Can anyone recommend sensors with good reputations that fire out generic N2K data, not fussed if they are wired or wireless.

Matt

[Nekton73]

I don't have a suggestion for a data capable unit, but I've had great reliable service from a Hawkeye depth unit like this (although I think mine is a D10X or something):


https://www.amazon.ca/HawkEye-DT1B-D...946791196&th=1


I went for the glue on installation inside the hull and eliminated the old through-hull transducer. Works perfectly. Has both shallow and deep water alarms, and I like the stand alone display. All I really need at a glance.



I don't have a speed log installed yet so I rely on GPS however I have been considering a stern mounted wheel log. My buddy has one that is part of his fish finder transducer, it just suction cups to the stern. Seemed to work pretty well when we tried it on my boat. I haven't looked much at other options yet so I will be interested to see if anyone has a suggestion for a non-through-hull speed log. I would like to have the ability to read STW again.

[GILow]

Originally Posted by Nekton73

I don't have a suggestion for a data capable unit, but I've had great reliable service from a Hawkeye depth unit like this (although I think mine is a D10X or something):


https://www.amazon.ca/HawkEye-DT1B-D...946791196&th=1


I went for the glue on installation inside the hull and eliminated the old through-hull transducer. Works perfectly. Has both shallow and deep water alarms, and I like the stand alone display. All I really need at a glance.



I don't have a speed log installed yet so I rely on GPS however I have been considering a stern mounted wheel log. My buddy has one that is part of his fish finder transducer, it just suction cups to the stern. Seemed to work pretty well when we tried it on my boat. I haven't looked much at other options yet so I will be interested to see if anyone has a suggestion for a non-through-hull speed log. I would like to have the ability to read STW again.

At that price I’d consider one as a backup anyway.

But it does seem that it’s a black-box solution, no way of extracting data is mentioned in the manual.

[goboatingnow]

Airmar do a nema 2000 triducer , this could easily be bridged on Wifi AVR then picked by custom display heads.

[GILow]

Originally Posted by goboatingnow

Airmar do a nema 2000 triducer , this could easily be bridged on Wifi AVR then picked by custom display heads.

The airmar triducers are the ones that seem to be giving people a lot of trouble these days.

[Muaddib1116]

The only problem with my airmar is that the paddle wheel gets clogged with growth after a few days of not moving. It usually starts up after a while underway at speed, but sometimes not. Often times the backwash of anchor power sets will free it up. I have considered changing to a particulate sensor style triducer, but I've heard the optical sensor gets covered in grime very easily and then you lose speed again. Maybe I just have to go swimming more often and dive down to free up the paddlewheel.

[Davidasailor]

The temperature sensors in Airmar triducers are notoriously short lived as well. Mine started reading 40 degrees high at about 5 years old, and can’t be recalibrated. For what I’ve read that’s not uncommon.

The little flapper that Airmar uses to reduce water flow when removing the transducer is also fragile. Mine was replaced once under warranty and failed again shortly after that.

Unfortunately they’re about the only game in town, or at least the biggest name, for transducers.

[GILow]

Originally Posted by Davidasailor

The temperature sensors in Airmar triducers are notoriously short lived as well. Mine started reading 40 degrees high at about 5 years old, and can’t be recalibrated. For what I’ve read that’s not uncommon.

The little flapper that Airmar uses to reduce water flow when removing the transducer is also fragile. Mine was replaced once under warranty and failed again shortly after that.

Unfortunately they’re about the only game in town, or at least the biggest name, for transducers.

Yes, everything you’ve described seems to be common. But the real kicker seems to be the depth readings failing early in the device’s life. And of all the sensors that matter to me, that one is the most important.

I really could get by without water speed, and I can solve temperature readings easily enough with a ds18b20 probe.

I am thinking I’ll try one of those in-hull depth sensors for now. As you say, the Airmar seems to be the main game these days.

[GILow]

Originally Posted by Muaddib1116

The only problem with my airmar is that the paddle wheel gets clogged with growth after a few days of not moving. It usually starts up after a while underway at speed, but sometimes not. Often times the backwash of anchor power sets will free it up. I have considered changing to a particulate sensor style triducer, but I've heard the optical sensor gets covered in grime very easily and then you lose speed again. Maybe I just have to go swimming more often and dive down to free up the paddlewheel.

In defence of Airmar, I don’t think we can blame them for marine growth. All paddle wheels will suffer this problem to some degree. Can yours be removed when not in use? Most can, though I have heard many of the Airmar sensors suffer problems with the water ingress prevention valve breaking off.

[Muaddib1116]

Originally Posted by GILow

In defence of Airmar, I don’t think we can blame them for marine growth. All paddle wheels will suffer this problem to some degree. Can yours be removed when not in use? Most can, though I have heard many of the Airmar sensors suffer problems with the water ingress prevention valve breaking off.

My dst800 is definitely not new, at least 5 years old, probably more. Everything seems to work properly, given the paddlewheel is not clogged.

Is there really a lot of incidence of failure with these things? I can't claim to keep track of everything in this industry, but I haven't heard or seen anything to indicate that Airmar transducers are prone to failure.

If depth is the only thing you really care about, Airmar does make a sensor that you glue to the inside of the hull (assuming it's solid, non-cored glass), which doesn't require a hole.

[GILow]

Originally Posted by Muaddib1116

My dst800 is definitely not new, at least 5 years old, probably more. Everything seems to work properly, given the paddlewheel is not clogged.

Is there really a lot of incidence of failure with these things? I can't claim to keep track of everything in this industry, but I haven't heard or seen anything to indicate that Airmar transducers are prone to failure.

If depth is the only thing you really care about, Airmar does make a sensor that you glue to the inside of the hull (assuming it's solid, non-cored glass), which doesn't require a hole.

If I am reading the complaints correctly, there seems to be a problem with the more recent units. I think the older ones are less trouble prone.

Which is a worry if you happen to be ready to buy one now.

Yep, I’m interested in the in-hull option for a number of reasons. The boat is solid core, however it is pretty thick down there, which raises some questions about how well the in-hull option will work.

More homework for me there.

[Nauticatarcher]

I have an Airmar P79s smart transducer, nmea 2000 in hull shoots through thick fibreglass fine, https://www.airmar.com/productdescription.html?id=108

[goboatingnow]

Interesting are there any ultrasonic based speed sensors that are completely in hull

The airbag 900 ultrasonic speed series doesn’t allow anti fouling and states “ performance will be reduced within weeks “ dont quite see the point.

[Tupaia]

CruzPro used to make a NMEA depth transducer.
NASA Marine make an excellent electromagnetic NMEA speed transducer.

[Jim Cate]

We've used a thin coat of antifouling paint on our paddlewheels for years, and it will keep growth off for a few months... less in bad fouling conditions. But it only takes a few minutes to renew the paint each time... i use a Q-tip as an applicator.

Won't help with some shrimp or drifting weed, but barnies and soft growth are much reduced.

Jim