Topic: Two transducers

[Justins]

A technical question I am just setting up a SI transducer on the hull and was wondering if anyone runs a second transducer on the opposite side of the hull. Wanting to know does the second transducer interfere with the beam from the SI transducer. If so is there a way around it.

Thanks
Justin

[George]

Justins

Depending on the boat some of the folks need to use two SI transducers to get side-imaging on both sides, when doing this they use a Side Imaging Splitter Cable that uses both SI transducers at the same time.

It you are going to use an SI transducer and let say a Quadra-Beam, for this you would require a switch to determine which transducer you wanted to use.  I have had 3 transducers hooked up at the same time by daisy chaining 2 switches. This allowed me to use any of 3 different transducers.

George

[Humminbird_Greg]

George is right on track here with what he told you Justin.
What two transducers are you thinking about connecting?

[Justins]

so far I have read that the SI transducer on the 998 are not all that good at hi speeds and I have never had a problem with the 597 transducer at hi speed. I  wanted to run the 597 as solely a plotter and the 998 as a sounder. Using the transducer from the 597 on a y cable or leaving it hooked up to the 597.
What I wanted to know most was does the beam from the SI transducer as it leaves the side of the transducer come out from the seam out and down. How close can I set the 2 transducers next to each other without the SI being affected by the signal being interrupted by the other transducer in the way.

I need a transducer to read well at high speeds as many trips are 100+ km in each direction crossing through shallow areas. The 597 transducer has been very good at hi speed 25 knots. If the SI transducer works well at hi speed I won't bother with 2 transducers however from a few opinions they don't and from experience on friends boats theirs don't either.

Thanks for the input

Justin

[Humminbird_Greg]

The Si beams radiate out of the full sides of the HDSi transducer.  They are angled so that some of the Si beams go upwards and not just straight out of the sides of the transducer.  I doubt that you could mount a second transducer beside a Si transducer and not have it block some portion of the Si sonar beam to that side.  How much it will block is all dependent on how close the second transducer is and how big the transducer is.  It’s like sticking your thumb up in front of one of your eyes: the farther away it is (and the smaller it is) the less it blocks your vision.  One way around this is to install the second transducer inside-the-hull or place something between the Si transducer and the transom so that it stands the transducer off far enough that the second transducer does not block any of the Si sonar.

Whether the HDSi transducer will work well enough at high speeds is all dependent on where you can mount it on your boat hull, and how the water flows off the boat hull.  The best location for a transducer at high boat speeds is not always the best location for Si sonar readings and may expose the (more expensive) HDSi transducer to underwater hazards.  It can also affect the water flow to the water intake on some motors/boats as well as the water flow through the propeller.

[Justins]

Thanks for the input Greg. I have got the SI transducer about an inch off the back of the transom so I could fit the other transducer further towards the chine of the boat and hard up against the transom for more clearance. Also is the SI transducer as good at 2 d work as the standard 597 transducer as I still will use 2d when out wide.

Justin

[Humminbird_Greg]

Yes it is Justin.  The HDSi transducer has the same internal element in it as is used in the 597 unit’s DualBeam transducer.

[Justins]

Thanks for everyones comments. I ran the boat yesterday and could still read bottom at 25knots and I usually cruise at 22 so there will be no need to run a second transducer. Si picture was good and only had noise from the prop if the motor was trimmed all the way in and running above idle.

Justin