Topic: altimeter/depth gauge

[yvautrin]

Hi All,

Using my side scan, I would like to add a "altimeter" or "depth gauge" to it in order to know at exactly what depth from the bottom is my unit when i tow it inctead of doing calculation with the length of rope, etc...

The idea would be to attach a "sensor" to the unit, with a cable running along the towfish rope, with a lcd display on board providing real time information about the sonar.

JW Fisher sells one of this kind for the very affordable price of 1 300$ !!!?

If anyone has a DIY alternative solution, I would love to hear about it!

Thanks.

Yann

[Rüdiger]

Hi Yann

Welcome to the forum 
Use the same time a second depth sounder, then you've got the original depth and when you peel the depth of the towfish which you can get the running depth of the fish.

mvh
Rüdiger

[yvautrin]

Hi rudiger,

Thanks for your answer!

I am quite new in SS technology, as I am only recently in charge of operating our JW SSS-100k.

The software we have is "sonar View", and on the boat, we have a raymarine c140w plotter/echosounder.

The problem I have is to be able to read in real time the depth of the unit as accurate as possible.

As far as now, I did not find a way to connect the raymarine unit to any software allowing me to read the SSS information in the same time as the echosounder...

I can do that by post-processing the information but i would like to be able to do it live...

Sorry if my question look stupid, but as I said, i am a newbiw in this field!

Thanks for your assistance !

Yann

[Rickard]

Hi Yann,
 
You really have some good gear, we are jealous! I have no solution to your integration problem, but it strikes me that towfish depth could be measured with a depth sensing transducer that is mounted to the towfish, but directed towards the surface. The water-air boundary is very reflective so the surface should be easy to detect. Perhaps this is how towfish depth is sensed in some systems?
 
Rickard

[Rickard]

When a standard HB SI or HDSI transducer without cork cover is used with a towfish the surface appears clearly in both SI views. I think it's the same with some other towfish systems. Depth is about 30 m in the example below. Of course, range must be set to something longer than depth for this to be possible.
 
Rickard
 
 

[Jolly Roger]

Well Yann,
you actually have the "depth sensor" right there in your fish. Just use it  !
Here's how I get the depth of my fish when towing it:
I mounted a transducer switch and hooked up both the fish and the transom mount transducer. I switch back and forth between the two ducers. By doing so I just have to substract the fish reading from the transom mount transducer's reading. Then I have the depth the fish is at.

Regards/Harry

[yvautrin]

Hi Guys,

First of all, thank you for your replies!

As I told before, I am new in using this technology, and your explanation appears to me to be in chinese language!

Could you tell me in "basic terms" what I have to do? To my understanding, I do not need to "add" anything to My JW Fisher SSS?

Thanks a lot again for your help!