Update the software to 3.5. it's the latest. there has been software fixes for the erratic depth issues

Ok, thanks for the info!

I have 2 hds lowrance with si/di networked.one bow and one at the console The lss transducer is mounted on the back of the boat.

I recently bought a hummingbird 10 si/di. I plan to mount it at the console also with the bird transducer on the back of the boat as a stand-a-Lone unit. Can I install the bird transducer on the same level as the lowrance transducer and expect side imaging and/ or down imaging to work on both brands? Thanks for the information in advance.

Humminbird's SI covers from the water's surface to past vertical under the transducer on both sides, so anything within that coverage will produce a recorded echo.

Depending on what model Humminbird (Helix or SOLIX) and which generation, you may have 4 frequencies that will cross-talk with the Lowrance unit.
So exactly what model and what generation Humminbird do you have?

Thank you Wayne. It is a G2 Helix. Just bought it new. I really wanted it for lakemaster use but would like to use other options at the same time as the lowrance too.

There are two issues of Helix 10 CHIRP MEGA SI GPS G2N's.
One was discontinued last year before the G3N's were produced, it is the 2017/2018 model,.
One is a HW promo version produced and sold recently by Cabelas and Bass Pro and is a 2019 model.
The first six digits of the serial number is the day the unit was made YY MM DD

The older model has 83/200 kHz single frequency or Chirped for 2D sonar.
The HW promo model has HW CHIRP 140-240 kHz for 2D sonar.
Both versions have 455/800/1200 kHz single frequency or Chirped for Side Imaging and Down Imaging.

Any two units operating at the same time on the same frequencies will cross-talk when their sonar pulses overlap. That is a sure thing for 2D sonar and Imaging with the transducers that close.

The Lowrance normally uses 83/200 kHz for 2D sonar and 455/800 kHz for Side Scan and Down Scan.
The older Humminbird G2N uses 200 kHz all the time for the Depth readout no matter what frequency you choose to view.


Sooooo, to get any useful sonar data on both units at the same time, don't use the same frequencies.

Gotcha. But installing them a ft or so apart on the same plane is ok?

Yes for waters deep enough so side blockage is not an issue.
Humminbird's SI will cover hundreds of feet with the outboard skeg stuck in the bottom.

I'm going to likely be repeating a question that has been covered but this is a 135 page thread. I purchased a Helix 12 inch G3N CHO with CHIRP , MEGA DI Plus, with GPS. I am placing at the bow where I have an existing Lowrance GEN 3 9 inch unit. My purpose is to have standard sonar and MEGA 360. The MEGA 360 is on backorder so I have some time to think about installation which I'm currently doing. I am going to set it up on my own and am placing it on the bow of a ZX 250. Luckily I have unused power leads to the bow so no need to pull a new circuit. Here are my questions:

1. I have an Ultrex with universal sonar and that is the standard sonar. Not the DI or SI transducer. When I unplug the connection to the Lowrance transducer, what Humminbird cable do I use to connect US to the Helix?
2. When I eventually receive the MEGA 360, what cable is used to connect the MEGA 360 and the Universal Sonar?
3. I assume if I wanted to , I could also attach a DI transducer to the trolling motor. So with that transducer plus the US and MEGA 360, is there a cable that connects all three? It seems somewhere I saw that the MEGA 360 or a DI transducer may connect via an Ethernet port.
4. I simply have not seen this kind of guidance in instruction for Humminbird and I am new to Humminbird having never owned a HB unit.
Thanks for any help.

1. Don't, you would be removing the MEGA 360 capability. Don't get the CHO and install the MDI+ transducer on the US2 trolling motor.
All third generation Helix units and second generation SOLIX units have standard HW CHIRP 2D sonar 140-240 kHz.
2. None, get the Helix MEGA 360 Y cable and connect the MEGA 360 and MEGA DI+ transducer to the display.
3. Forget you have US2 transducer. Ethernet has nothing to do with MEGA 360 other than it can be shared to G2N and other G3N units via Ethernet. The MEGA 360 is a transducer connection NOT an Ethernet connection like the 360 is.
4. I have the MEGA 360 and run it with a Helix 12 CHIRP MEGA SI+ GPS G3N, but use the MDI+ transducer since you cannot connect both the Side Imaging piezos and the MEGA 360 to the unit. The MEGA 360 replaces Side Imaging.

So, I have to purchase that $220 attach to the bottom of the trolling motor transducer?
Humminbird XTM 14 HW MDI T (710291-1)

You did state HELIX????? That is a SOLIX transducer.

It's simple, get the Helix 12 CHIRP MEGA DI+ GPS G3N. It comes with the MDI+ transducer that fits a Helix MEGA DI+ unit.
Then get the Humminbird AD MTM HW MDI mount for it.
https://humminbird.johnsonoutdoors....i-mega-di-trolling-motor-adapter-bracket

The first few uses of the MEGA 360, I was using the 360 and MEGA 360 with dual Helix 12's.
I posted some screen shots on BBC in the Humminbird Image Interpretation threads.

That's a strong question with five question marks! Yeah, I have a Helix. I have the unit but I did not get a transducer. At the time I thought it would take a combination of a MEGA 360 plus a standard transducer (the US on the Ultrex). I am not an expert or even familiar with Humminbird, I am first time Humminbird user and a fool with enough money to buy these toys. I will have to purchase a trolling motor mounted transducer. It seems you are saying standard sonar and down imaging come from the same transducer and I don't need another transducer for sonar or imaging beyond those two. I think my Lowrance units use a thru hull standard transducer and the SI/DI transducer on the jack plate. I'm not familiar at all with the proper combination of transducers to run standard sonar and DI on a Humminbird but I will get it right. I was going to call Humminbird tech service tomorrow to ask the same questions. I don't know when the MEGA 360 will come off backorder. My Ultrex was on backorder for months before it was shipped. I can't even find the Y connectors in stock anywhere.

And thanks!

You do seem confused, now I understand.
Since you already have a Helix DI+ CHO, then get the XTM 9 HW MDI T transducer. It will include the trolling motor mount, two stainless steel hose clamps and a RFI choke for the battery charger lead if you have an on-board charger that does the trolling motor battery/s and the starting battery.
Humminbird transducers for Helix units have a 9 in the model name, transducers for SOLIX units have a 14 in the model name.

If you would have purchased the unit with transducer, it would include a transom transducer that does Down Imaging, HW CHIRP 2D sonar, and temp---then all you would need is the trolling motor adapter.
The Side Imaging version comes with a transducer that does Side Imaging, Down Imaging, HW CHIRP 2D sonar, and temp. Most that get either of those models for the console, also get a shoot-thru HW transducer for the bilge if their hull is suitable for a shoot-thru application.
The two transducers are connected to the display with a 2D splitter Y cable. That SI transducer is what Lowrance copied with their "triple shot" and "all-in-one" transducers. The Humminbird ONIX SI model was the first with the "all in one".

Next best would have been getting the Minnkota trolling motor with built-in MDI transducer instead of the US2.

With the MEGA 360, it connects to the unit's single transducer port, and takes the 9 M360 2DDI Y cable to connect another transducer with the MEGA 360 transducer to the unit's single transducer port.
If you get all the parts before the Y cable is available, you can still use the Helix adapter cable that comes with the MEGA 360 to at least do SI and MEGA 360. It comes with a SOLIX cable also.
The MEGA 360 works fine without another transducer, just need another one to have a depth readout of the MEGA 360 view.

A person in Finland has posted some MEGA 360 screen shots today so the first wave of units have gone out world-wide. Looks like he doesn't have the MEGA 360 Y cable either, can tell by the missing readouts on his screen shots.
First few times I used mine, it was just with the MEGA 360 connected to the G3N.