Fishfinder Vs forward looking sonar

[shanson 0]

Been thinking about this on and off for a while.

 

Is there any reason I can't use a spare fish finder as a forward looking sonar?

 

Sure I'll have to find a way to face the transducer forward but?....

 

Shane

[wheels 543]

Yep you can, but it is in how you interpret the return echo. The very first Interphase that came out was basicaly just that. And the return was not the best when compared to the more modern units. Infact back then it was kind of like, if you saw an object on your screen, it was already too late to take action. That return and returns of all sounders for that matter, are interpreted by Algorythyms. Thus tThe modern units are able to display alot more information.

The issue with facing a standard sounder forward, is that a return echo will not be able to be interpreted with depth below surface. If an object is at the surface, 10m, 20, or whatever bleow the surface, you will get a flat line on screen, instead of just the size and depth of object. All transducers have an arc of operation. You need to angle the transducer to have the arc parrellel to Sea surface. It will at least give some kind of return.

But then, if you are going to buy another Fishfinder to do this, you may as well buy the proper unit.

[shanson 0]

Thanks Wheels

 

I have a couple of fishfinders lying around, hence the thought.

 

I also have a narrow beam Humminbird which I thought would be ideal, but your correct it's all in the way it's interpreted.

 

Might tie it to a pole in the marina and see how it works.

 

SHANE

[PaulR 3]

For transducer details; cone diagrams etc

check www,airmar.com who make a lot of transducers for many different brands. See wiring diagrams etc as well.

 

Enjoy.