Cone angle and vessel position

[luke343]

Hi Guys,
I have a thought and thought I would ask someone smarter.

So when fishing deeper water. 400-500m. A quick calculation say the transducer cone on the bottom is large. So is what is showing under on the sounder under the boat or 100m away?

cheers Luke

 

[Snips]

Luke343,
You didn't mention the transducer.
For example, a B-260's (50Khz) has a foot print of 100ft and 200Kh is 31ft at a 300ft depth.

Snips

 

[luke343]

Thanks Snips, I knew I forgot something.
I am running a 18 degree 1 kw 50 hz Radarsonics non chirp on a DDF1, in 500m of water the maths says the cone if sizable. A bit more time on google has me slightly more confused.. Is there a magic formula you use to estimate the cone size? Various formulas have it form 180m to 400m ish, while 180 is acceptable to assume it is under the boat 400m is a bit of guess work.

It was just a thought as the line takes 5min to get to the bottom! or would it be better to go to a narrower beam deeper than 300m?

Apologies for the daft questions, I just couldn't find the answers around I wanted.

cheers Luke

 

[Snips]

Luke343,
A 18 degree cone at a depth of 500m covers 159m.

Snips

 

[luke343]

Thanks Snips,
That is a better number to what I found and puts it close enough to under the vessel!

Thanks again Luke