Topic: SI Transducer Position

[deepend]

Ignore how dirty the boat is...fished a few power plants this winter and haven't washed it up yet.  I plan on leaving the transducer that is there on there so I can get bottom readings with the dash depth finder while on plane.  Will I have troubles if I mount the other transducer to the left of it?

I heard you want to mount it about a 1/4 inch below the boat line.  This is already at about the lowest point of my boat. Will I have issues?

Where would you place the SI transducer?

 
 
 

[Humminbird_Greg]

Since you are going to leave your existing unit and transducer for high-speed depth readings then you do not have to mount the HDSi transducer below the hull.  In fact you have more freedom in where to mount it.  I would try mounting it as far away from the transducer you now have on the boat.  The farther away the less Si sonar it will block, so we are looking at the left side of the motor and as far out on the transom as you can go while still allowing it some protection from stumps and such.  Maybe where I put the bright green rectangle?

[sonar2000]

I would suggest one step to the right of where the green block is. Is that a Lowrance skimmer transducer.  If so it should not interfer with your HB unit..
The hbsi is susceptible to beam interference as it is so wide top to bottom, so you might see some right side stuff from the motor unless it is tilted up and away. Do you run a trolling motor? This will help to get the main motor out of the way for trolling speed.
Chuck

[Humminbird_Greg]

If that is a Lowrance skimmer transducer and the unit runs at 200kHz than yes it can cause interference with the Humminbird unit as they both run at the same 200kHz frequency.  No guarantees that it will but the chance is there.  You may be able to turn on and up the Noise Filter menu setting in the Humminbird or change the Ping rate setting in the Lowrance to counter this or it may be so bad that you have to shut one of them off.  Either way that transducer and anything else that sticks out from the hull can block some of the Si sonar and what you want to do is reduce the amount that it does this.  The only way to do so is to either mount the Humminbird Si transducer on a block or something that will place the transducer farther away from the transom (so it shoots its Si sonar beams behind the other transducer) or separate them by as much distance as you can to minimize the blockage.  Think of it this way: your thumb is not that big and if you hold your arm out in front of you at arm’s length and stick you thumb upwards little of your vision of what is in front of you is blocked.  Now bring that thumb to right in front of your eyes and you will find that it blocks more of your vision.  Same thing happens with transducers; so keep them as separated as you can.

[sonar2000]

I thought the HB ran at 262....
Chuck

[Humminbird_Greg]

Some of the Si units have the 262kHz Si sonar frequency option Chuck.  The interference he will see will be from the more conventional 2D sonar at the 200kHz frequency.

[sonar2000]

OK, I looked some more at that and you are correct.
Chuck