Topic: 998csi glitches with XNT 9 20 T high speed transom transducer

[Gillfisher]

I have tried to connect 2 different high speed transducers to my 998 and I can not get them to work properly. What happens is the chart speed slows to a crawl and it gives a pulse on the screen like a heart beat on an EKG and will not read anything in the water including the bottom. Also when out of the water and in my hand the transducer will send out just a short burst of pulses then it sends out real light pulses that are about a second apart or so.

I have tried two different XNT 9 20 T transducers and 2 different AS SIDB Y cables to no avail.

I have also tried plugging the transducers into the 998 unit directly and choosing the dual beam transducer from the menu as well as the 200/83 menu option (and all the other menu options under the transducer setting) and none of these work.

Is this transducer not compatible with my unit? If not which one do I need? Is something wrong with the 998 unit itself?

The reason I want this is I am not satisfied with the on plane reading I get with the large SI transducer. I tried this 2 years ago when I bought the unit and couldn't get it to work then, and now I purchased new components thinking I may have gotten bad stuff the first time around and still it does not work.

I am running 6.68 on the unit now and I do not remember which version I had when I tried it a couple years ago.

The picture is from the first attempt, I get the same results now with the new version of software and new y cable and transducer.

Thanks for any help you can give me with this.

[Humminbird_Greg]

Gillfisher,
What does the 2D sonar look like with the HDSi transducer connected?

[Gillfisher]

Gillfisher,
What does the 2D sonar look like with the HDSi transducer connected?

The 2D sonar is fine with the HDSI transducer except at high speed, which is why I am back to the second transducer

[Austin358]

Gillfisher, I have 100% the exact same problem except my graph is brand new only about 10 days. If you unplug your si transducer and plug in your 2d transducer by itself do you still get that same crap?  My does. Humminbird Greg told me to pull the puck out of the transom, clean the epoxy off of it then go put the boat in the water and hang the puck over the side to see if it reads then. I would guess this is to see if we have them mounted in a bad location.

[Gillfisher]

Yes I get the same thing with just the 2D transducer plugged directly into the back of the unit , I tried every transducer from the menu options also with the same results. Mine is the transom mount transducer and I get the same thing in and out of the water.

[Humminbird_Greg]

Sounds like you need to replace your 2D transducer than Gillfisher.

[Gillfisher]

It has done the same thing with 2 brand new transducers, and 2 brand new y cables. I think it's a bad 998 unit.

[Humminbird_Greg]

Than I am confused Gillfisher as you stated: “The 2D sonar is fine with the HDSI transducer except at high speed, which is why I am back to the second transducer”.  The HDSi transducer has the same 2D sonar elements and connections within it as does the 2D transducer.  If there were a problem with the unit it would show up with either transducer connected to it.    

[Gillfisher]

It seems extremely odd that I have drawn the short straw twice in three years and got bad transducers. I guess it's possible but doesn't seem probable. I am going to check the two transducers on my 788 the next time I get home and that should eliminate one or the other. I really figured I had the wrong model of transducer. I will let you know what happens with the 788.

[Humminbird_Greg]

If the 998 unit would not read correctly on those two transducers then the 788 should not read correctly on them, but it will be good to test them anyways.

By the way; the XNT-9-20-T transducers are the correct ones for this and you can leave the unit set to use the Hi-Def Sidescan transducer when testing them.

Just wondering here: why would you not install an inside-the-hull (XP-9-20) transducer instead of a transom mount DualBeam transducer?

[Gillfisher]

I have an aluminum Lund

[Humminbird_Greg]

Gotcha Gillfisher.  Inside-the-hull transducers don’t work to well in tin boats.

[Gillfisher]

Okay I tested both transducers on the 788 unit, one produces the exact same thing with the heartbeat and the other one works just fine. So now I am even more perplexed about the whole thing. I did not try the y cable on the 788 to see if that worked or not. I may try that before I head out of town again.

[LittleGazoo]

Can you test your units on another boat that a similar transducer setup?

[Austin358]

Next in the list

[Gillfisher]

Can you test your units on another boat that a similar transducer setup?

I cannot