Topic: Adding a second transducer for depth readings at speed?

[RivRunR]

Great site! 
I've got an 898c SI on the console and a little 141c on the bow of a Lowe 1752 Roughneck (aluminum).  I've adjusted the transducer location / angle, but I still lose depth readings above 25 - 30 mph.

I'm not going thru-hull on an aluminum boat, so I think that the best possible fix is adding an XNT-9-20 T with an AS SIDB Y cable for reading depths at speed.

I've read lots of posts here on this subject, but I'm still a little confused:

1.  Assuming it has the same basic location mounting instructions, is it just the smaller footprint (less turbulence/bubbles) of the XNT-9-20 that allows readings at speed?  In other words, if I mount it the same way, why does it help?

2.  I get occasional sonar cross-talk between the 898cSI and the 141c.  The 141c uses a US2 transducer in the trolling motor.  I'm thinking that the XNT-9-20 will ping constantly, and the "transducer select" option only controls what is displayed(?).  So, if I add this second transducer to the transom, is that going to further compound my cross-talk problem?

I appreciate any advice or thoughts you guys have....

 

[Humminbird_Greg]

1. Yes.  The smaller transducer is easier to locate in a position that will work versus the bigger HDSi transducer.  It is also less expensive to replace should it become damaged.  It also allows you to locate the HDSi transducer where it will work better for the Si sonar. 

You may also want to look at the XSO-9-20-T Stick-On transducer or the AlumaDucer which is built by RadarSonics (http://www.radarsonics.com/AlumaDucer.htm) as some have used these on aluminum hulled boats with good success.

2. No it will not make this worse.  When using the AS-Si-DB-Y cable the 2D sonar for the 898c Si unit will always come from the XNT-9-20-T transducer (or whichever transducer you end up using) and not from the HDSi transducer.  The AS-Si-DB-Y cable disconnects the 2D sonar that went to and from the HDSi transducer and routes it to the XNT-9-20-T transducer.

You need to try turning on and up the Noise Filter menu to try and counter any sonar cross-talk.

[RivRunR]

Ahhhh, that makes perfect sense...thanks Greg.

When you say "allows you to locate the HDSi transducer where it will work better..." does that mean just higher up on the transom?  Like raised up to the maximum point possible while still staying submerged?

Thanks again!

[Humminbird_Greg]

It could be.

Most will mount the HDSi transducer up higher just to help protect it.  At $250+ dollars a pop it can be quite expensive to replace!

Sometimes the best location for unblocked Si sonar readings are not the best location for high-speed depth readings.  This, of course, is dependant on each boat due to mainly hull design but also due to motor size, setup and loading of the boat itself.  Let us not forget any extras that may be hanging off the transom such as a ladder or kicker motor.

[RivRunR]

Again, thanks so very much for all the help!

[RivRunR]

I should've known I'd have another question!

With the XNT-9-20 and Y cable, will I have to use the "transducer select" menu?   Or,  because the Y cable disconnects the 2D from the HDSi transducer, will it just automatically receive 2D from the XNT, and SI from the HDSi without having to select a transducer from the menu?

Thanks!

[Humminbird_Greg]

You will not have to use the Transducer Select menu.  You are correct in that the 2D sonar will always come from the XNT-9-20 transducer while the Si sonar and water temperature will always come from the HDSi transducer.  The AS-Si-DB-Y cable disconnects the 2D portion of the HDSi transducer from the unit and replaces it with the 2D connection to the XNT-9-20 transducer.

[RivRunR]

Again, thanks.  Appreciate all the support you provide here!

[RivRunR]

Apparently I just can't leave well enough alone!

Now that I've added the XNT-9-20-T via the AS-SIDB-Y cable, I'm looking at another transducer.

If I get an XNT-9-QB-90-T Quadra Beam transducer, can I still use the same AS-SIDB-Y cable to split the signal to the 898c SI?  The HBird site describes the Y cable as "...dual beam only", but the 898 manual says a Quadra Beam is compatible, so I wasn't sure.

Is the Quadra Beam worth the effort?  Will I need to change any setup menu options?

Thanks for your patience!

[Humminbird_Greg]

If you were to use a QuadraBeam transducer with the AS-Si-DB-Y cable it would depend on how you plug it up:
 - If plugged into the “DualBeam” connector; only the DualBeam portion (2D 200/83KhZ) of the QuadraBeam transducer would have any electrical connection to your unit.  You should not see any difference between having the QuadraBeam connected this way versus a DualBeam transducer.
 - If plugged into the “Side Imaging” connector; only the temperature sensor and the 455kHz Side Beams of the QuadraBeam transducer would have any electrical connection to your unit.  You should see a reduction in the detail in the Si and Di sonar versus the standard Compact Side Imaging transducer.

To use the QuadraBeam transducer as intended, you would have to change the “Transducer Select” (now called “Connected Transducer” menu) to the “Quad Beam” menu setting.

To make this work with your current system you would have to purchase and install a TS3 Transducer Switch in between the QuadraBeam transducer and the AS-Si-DB-Y splitter cable (where it plugs into your unit).

The only way that I could see that the QuadraBeam would be beneficial would be if you were to be able to epoxy it in the hull of your boat and want to see the Side Beam data while travelling at high boat speeds.  Otherwise, in my opinion, it is a step back from the Side Imaging sonar.

[RivRunR]

Ok, so if I understand what you're saying (and maybe I don't), the Quadra Beam would effectively replace the Si transducer instead of giving enhanced imaging beyond what the 9-20-T would give?  I was thinking that the Quadra Beam would just be kind of a higher-end version of the 9-20-T.

[Humminbird_Greg]

Yes, the QuadraBeam transducer would replace the Si transducer.

Basically the QuadraBeam is a DualBeam transducer with the addition of two downwards-and-to-the-side pointing 2D sonar beams.  For non-Si units it can give additional information if you understand what it is showing you.  For most though, I think that Si sonar would give them more information that is easier to understand.

[RivRunR]

But I don't use the Si sonar for 2D, I use the 9-20-T, which is why I thought the Quad, with it's additional 2D beams, would be an enhancement.

Sounds like this may just not be worth it, even tho I can't seem to comprehend why.   

I suppose I could throw the Y cable in the trash and get a TS3 switch for the Quad...but (I think) that would involve flipping the switch AND changing the menu transducer select every time, which would be more trouble than it's worth, especially when rotating through various views.

[Humminbird_Greg]

With the AS-Si-DB-Y cable the additional side beams of the QuadraBeam transducer would not even get connected to the unit, so the QuadraBeam would act just like it was a DualBeam transducer.

Correct: the TS3 switch with the QuadraBeam would work but you would also have to change menu settings… not worth it to most who have thought about doing this.

[RivRunR]

Thanks Greg