Ultrex 2d vs ultrex mdi

[Mftello]

Hello all. I have a question regarding whcih ultrex to buy. I have 2 helix units. A 9 mega si g2n and a 9 di g2n. I would like to pair them with an ultrex but cant decide whether to get one of the new units with the built in mdi, or last generations unit with just the 2d. There are some good deals on last generations models and in a perfect world, i would buy one of those, mount my di transducer on it, and call it good. However, i have been told that there are imaging issues related to a mounted di on an older ultrex. I was told that each time the motor moves, it causes a disturbance and creates a break in the image. Does anyone have experience with a mounted di transducer on last gens ultrex, how well it performs, and whether it is worth upgrading to the current generation ultrex with mdi? Thanks in advance for any help

[A-Jay]

Hello and Welcome to Bass Resource ~ 

While I am not running an Ultrex (still stubbornly rocking the 112 Fortrex) and my 2 Helix 10's are the generation previous to yours (2016) - I'd recommend getting the newest technology available. 

   The current rate of 'upgrades' year to year, seems to make even two year old gear almost obsolete and somewhat incompatible with the newer offerings. 

 Haven't heard a bass guys yet say "I am displeased with this new electronics package - it's too new" 

Usually it's the other way around and I'm getting there myself.

Good Luck.

A-Jay

 

 

[Tennessee Boy]

I would expect issues when you mount a traditional down image transducer on a trolling motor.  Down imaging uses a very wide and very thin sonar beam so turning it will change the area you are covering even if you are not moving.  If you understand how down imaging works and why you are seeing what you are seeing, it might not be a problem and might even offer some advantages.  Using the transducer for 2D imaging should work fine.  I've been trying to find out how the new Ultrex TMs with built in MEGA down imaging work.  I would love to know what the shape of their down imaging sonar beam is.  So far I have not found that information published anywhere. If the beam is wide and thin then they would have the same issues when the trolling motor turns.  I would think this would be unacceptable because it would cause confusion with most users who don't understand why they're seeing what they're seeing.  If the beam is not wide and thin,  then how does it give you the high definition images you expect with down imaging?  It's the thin beam that gives you the high definition.

 

As for what TM you should buy.   I have the old Ultrex and use the built in 2D transducer.  I have 360 imaging on my TM so I don't really need down imaging.  I strongly prefer using a built in transducer.  It's just much cleaner.  So I would buy the new version if I wanted MEGA down imaging but I would want to know how it works first.

[iabass8]

I use the previous gen ultrex /w lowrance electronics and use a HDI transducer on it. DI interference are usually install issues. There are very simple fixes to eliminate it if you search for it. I didn't have the option when I got mine a few years ago and want DI up front. If I were buying today, I would use the built in 2d/DI and call it good. 

[Janderson45]

For what it’s worth, your current helix DI graph will NOT work with the built in Mega DI transducer on the new Ultrex.  You would need the latest generation MEGA DI Helix or Solix to be compatible with the transducer offered on the new Ultrex.  

[Tennessee Boy]

20 hours ago, Janderson45 said:

For what it’s worth, your current helix DI graph will NOT work with the built in Mega DI transducer on the new Ultrex.  You would need the latest generation MEGA DI Helix or Solix to be compatible with the transducer offered on the new Ultrex.  

Here is a list of compatible Humminbirds.   Some units will not support the new MEGA DI function but many older unit will.

 

https://www.minnkotamotors.com/support/compatibility/Built-In-MEGA-DI

[Janderson45]

44 minutes ago, Tennessee Boy said:

Here is a list of compatible Humminbirds.   Some units will not support the new MEGA DI function but many older unit will.

 

https://www.minnkotamotors.com/support/compatibility/Built-In-MEGA-DI

 

Needs to be a MEGA DI G2N or G3N, hard to tell if the OP’s unit is MEGA DI or just regular DI.  That said, G2N Helix being compatible with the Ultrex MDI transducer is news to me, I saw contradictory information from Humminbird, but perhaps it’s compatible now with the latest firmware update?  Thanks for the link.

[Tennessee Boy]

1 hour ago, Janderson45 said:

 

Needs to be a MEGA DI G2N or G3N, hard to tell if the OP’s unit is MEGA DI or just regular DI.  That said, G2N Helix being compatible with the Ultrex MDI transducer is news to me, I saw contradictory information from Humminbird, but perhaps it’s compatible now with the latest firmware update?  Thanks for the link.

I just noticed something on the link I posted earlier.  The list has MEGA DI and MEGA DI+.    Only the newer units support MEGA DI+.  MEGA DI+ gives you more detail. Even though I have no intentions of replacing my 9 month old Ultrex,  I am very curious as to how this is going to work.

[Tennessee Boy]

I reached out to Minn Kota via online chat.  They referred me to Humminbird online chat.  Here is the transcript of that chat.

Quote

 

Me: Concerning the new MinnKota Ultrex with your MEGA DI transducer built in.  Can you help me understand how this will work?  Down imaging,  as I understand it uses a wide and thin beam to provide higher detail.  How will this work on a trolling motor that is constantly turning?  It seem like a different area would be covered by the beam every time the trolling motor turns which would be very confusing.  What am I missing?

 

HB: The DI would primarily be of benefit when travelling in a straighter path. Otherwise, there is also traditional sonar built into this transducer that will allow for bottom/depth returns while in the application of the "turning and twisting" of the motor.

 

Me: Can you tell me what the beam width will be with down imaging with this transducer?

 

HB: The maximum beam width would be 75 degrees and minimum would be 45 degrees.

 

So down imaging will work the same on the trolling motor as it does on the transom.  This surprises me.   If you're in 10ft of water using the 75 degree setting with the trolling motor facing forward,  the beam will be 37 ft side to side and will be about 2 inches front to back.  If you're on spot lock and the TM turns 90 degrees,  it will change to 37 ft front to back.  That front to back view could look very different from the side to side view.  If you understand why the screen is changing every time the TM turns,  this could provide useful information.  If you do not understand,  you will probably be calling Humminbird asking what's wrong with your fish finder.  On the 45 degree setting, it would be less dramatic (10 ft vs 37 ft).  Maybe I'm overestimating this effect.  I'm sure some of you have mounted DI transducers on your trolling motor before.  How well did it work for you?

[Janderson45]

On 1/11/2019 at 3:02 PM, Tennessee Boy said:

I reached out to Minn Kota via online chat.  They referred me to Humminbird online chat.  Here is the transcript of that chat.

So down imaging will work the same on the trolling motor as it does on the transom.  This surprises me.   If you're in 10ft of water using the 75 degree setting with the trolling motor facing forward,  the beam will be 37 ft side to side and will be about 2 inches front to back.  If you're on spot lock and the TM turns 90 degrees,  it will change to 37 ft front to back.  That front to back view could look very different from the side to side view.  If you understand why the screen is changing every time the TM turns,  this could provide useful information.  If you do not understand,  you will probably be calling Humminbird asking what's wrong with your fish finder.  On the 45 degree setting, it would be less dramatic (10 ft vs 37 ft).  Maybe I'm overestimating this effect.  I'm sure some of you have mounted DI transducers on your trolling motor before.  How well did it work for you?

I missed this post that’s why I’m just following up now. 

 

After a long day of working with numbers this is making my head spin, lol.  Let me dissect what you wrote, look at the transducer specs, do my own math and I’ll get back to you.  My initial impression is there has to be some part of the equation that you’re missing - if not down imaging on a trolling motor would be entirely useless?  It’s definitely not.

 

For what it’s worth, I recently stumbled across the idea of using transom mounted Mega DI imaging on a bow unit via Ethernet.  Obviously there’s going to be a delay between when you troll over something and when the transom mounted transducer would pass over the same water... probably like 1-2 seconds and ~20’ of distance between the trolling motor and transom.  In the past viewing all of the above as problematic made me write off the whole idea, after listening to an FLW pro and how he does it this exact way on purpose I’m now seeing the potential benefits of it and considering using DI in this manner myself.  

[Tennessee Boy]

@Janderson45  Wow you’re correct my math was crazy.  Not sure what was going on when I did that.  Should be 15.3 ft for 75 degree angle and 8.2 ft for 45 degree.  Thanks for catching that.

[Janderson45]

I looked into the concept that you were getting at though at it’s not entirely off base.. if the trolling motor head rotated 90 or 180 degrees while spot-locked the “slice” (for lack of better term) that you’re seeing on the DI from the transducer beam angle and width would certainly change.