50/200 khz and Fish Hawk Interference?

[pjprod]

I just installed a 50/200 Airmar P66 Transom mount ducer. I have a Fish Hawk X4D. My fish locator is a GARMIN 7610 XSV. When fish locator is on 50/200 split the fish hawk readings are all over the place. When i turn the 50 Khz off and run just 200 khz the readings are rock solid.  I spoke to others and they have no issues running 50/200 split as far as interference with Fish Hawk.  I have hawk wired to a fuse block up at the dash in front...i run a 15lb ball with hawk probe on same side as hawk transducer. Here is a pic of my back of the boat.  Picture to left shows Fish hawk ducer to the left and p66 to the right. Pic to the right shows trolling motor and i have room to move hawk ducer to left of transom strap near edge if need be. Any thoughts? i am stumped...Thanks... 

 

[nhjim]

running garmin and fishhawk also my two transducers are about 4' apart and when i get over about 50' deep cant run finder on 77 or loose the fishhawk. run on 200 no prob any depth.my setup looks similar to yours

[Sk8man]

What I'm wondering is not about your spacing on the hull but the cone angle of the two transducers (50 and 70) maybe coinciding down below such that the Fishhawk signal (ping) underwater is getting "confused" when they go deeper as they are being read by the Fishhawk transducer. The cone angle of the 200 khz is narrower and they may not be coming together and the frequency difference is greater in that case. Just a thought off the top of my head. The signal rejection may be weaker on the Fishhawk too.

Edited September 4, 2020 by Sk8man

[Rookie Fisherman]

From the Fishhawk manual.

 

"Mount the Fish Hawk Transducer as far away as possible from other transducers that operate within 20 kHz of the 70 kHz Fish Hawk Transducer"

 

So anything from 50-90 khz will have interference if not separated enough as the signal/cone angle can overlap. The deeper the water the more chance over overlap as the cone widens.

 

 

[pjprod]

Ok...thanks...that is my thinking is to move out as far as possible. I have the room to do it. Thanks and i will start from there. Any thoughts of wiring directly to battery?

[Rookie Fisherman]

https://fishhawkelectronics.com/content/X4-X4D_Manual_Web_2-27-2020.pdf

 

See Trouble shooting section.

[Sk8man]

"

The deeper the water the more chance over overlap as the cone widens"

This is what I was referring to in my comment.. it is possible that if you are going deep enough they may meet regardless of where the transducer is mounted as some of it probably depends on the depth finder signal strength when on the 50 khz and the ability of the Fishhawk screen out or to reject a potentially stronger signal. There is no guarantee regarding an optimal placement. By the way, my Lowrance transducer (83/200) shares a screw with the Fishhawk on the same transducer mounting plate and they run OK together although I did make some adjustments in the Lowrance settings.

 

Edited September 5, 2020 by Sk8man