MEGA SI issue 2024

Further North reply :

I have a newly installed Helix 12 G2N SI and while I am absolutely amazed by the quality of the new SI imaging...I lose 2D depth when running faster than about 10 MPH.

Unit is installed on an '05 Crestliner CMV 1850. I can provide pictures of the install if that will help.

This is an upgrade from a Humminbird 1198, never had any issues like this with the older transducer.

Thanks in advance for any help!

MickD reply :

Been there, done that. The fact is that the mega transducer is incapable of giving depth at over about 6-10 mph. What Humminbird doesn't mention in their advertising, and what the sellers don't even know (I think) is that you need another $100 bucks in hardware to get that depth reading at speed. Go to the support section of Humminbird.com and search for "high speed," as if 10-20 mph is "high speed," and you'll find the extra transducer and Y cable needed to get the depth reading at speed. The Y cable doesn't tie in at the stern; it ties in at the unit, so the new Y cable has to be run all the way from the unit to the stern where the new transducer will be mounted next to the mega transducer. My boat seller actually tried to sell me that no one really needs to know how deep the water is at speeds over trolling speeds.

I think this is a big issue that Humminbird and their dealers are not stepping up to. Humminbird smugly ignores it while the dealers plead that they just sell the stuff we call for and cannot know about all the variations of hardware and customer expectations. We consumers pay over $2000 for electronics that won't even indicate depth if the speed exceeds 6-10 mph. That is inexcusable.

The good news is that the new transducer works fine for depth reading at speed and the unit doesn't have to be switched between the two; they work seamlessly together without any switching required.

Further North reply :

Thanks Mick. I was thinking it could be something like that.

I have an extra DI transducer from the Helix 10 DI I installed at the bow (I'm using the 2D transducer bulit into my Ulterra for what I need up there, I can get everything else off the networked Helix 12)...I am thinking I can use that transducer to get 2D at speed.

On 5/8/2017 at 9:31 AM, MickD said:

My boat seller actually tried to sell me that no one really needs to know how deep the water is at speeds over trolling speeds.

I seldom make statements like this; but your boat seller is a fool, and a dangerous one.

A lot of people fish water that isn't mapped well and need that 2D at speed to stop from running aground.

Further North reply :

MickD reply :

I cannot really see whether that mega transducer is installed below the boat's surface. If it is it is not mounted according to humminbird's instructions. Mine was first mounted below the surface until I showed the dealer the humminbird instruction sheet. Now it's up above the boat bottom surface about an inch or a little more.

I'm not sure what transducer is compatible with the unit so you get good depth reading at speed. All I know is that there is one that humminbird recommends, it looks like a "conventional" transducer, it should be mounted so about half of it is below the surface of the boat, and it has to have a Y cable to "wire" it in.

Wayne P. reply :

On 5/9/2017 at 4:27 AM, MickD said:

I cannot really see whether that mega transducer is installed below the boat's surface. If it is it is not mounted according to humminbird's instructions. Mine was first mounted below the surface until I showed the dealer the humminbird instruction sheet. Now it's up above the boat bottom surface about an inch or a little more.

I'm not sure what transducer is compatible with the unit so you get good depth reading at speed. All I know is that there is one that humminbird recommends, it looks like a "conventional" transducer, it should be mounted so about half of it is below the surface of the boat, and it has to have a Y cable to "wire" it in.

Do you have a Humminbird MEGA SI unit?

MickD reply :

Yes, a 7 on the front and a 9 at the helm.

Wayne P. reply :

On 5/9/2017 at 8:52 PM, MickD said:

Yes, a 7 on the front and a 9 at the helm.

No such thing as a 7 MEGA unit. Do you know what MEGA stands for and what models are MEGA SI units?

MickD reply :

Right, the unit on the front is the Helix, both are Helix, the one on the helm is mega with the big flat transducer as shown in the photo above. Just to be sure I know exactly what mega stands for, please tell me. Also, Wayne, you are very knowledgeable on this stuff, and I'm sure many others besides me are appreciative of what we have learned from you. But I'm curious, you don't happen to be associated with Humminbird, do you?

Wayne P. reply :

MEGA stands for the new Imaging frequency using 1.2 MKz or 1200 kHz either as a single frequency or CHIRPed from 1.150-1.275 MKz.

There are 5 models that have MEGA Imaging:

Helix 9 CHIRP MEGA SI GPS G2N

Helix 10 CHIRP MEGA SI GPS G2N

Helix 12 CHIRP MEGA SI GPS G2N

SOLIX 12 CHIRP MEGA SI GPS

SOLIX 15 CHIRP MEGA SI GPS

All of those also have 455 kHz and 800 kHz Imaging single frequency or CHIRPed.

I am not an employee or pro-staff.

I use their stuff and help others with their Humminbird units.

12poundbass reply :

Wayne is the Humminbird wizard! He's the Harry Potter of Humminbird! Just kidding Wayne. You really know your stuff and we all appreciate your expertise.

MickD reply :

Good, I now know exactly what mega stands for. It is as I understood it, but good to know I'm not missing anything. I was just curious about a Humminbird connection, Wayne, no offense intended. As I said before I've learned a lot from you and appreciate it. In fact I've learned much more from you than from Humminbird and my dealer.

I believe my dealer is just uninformed. This stuff is so new he just doesn't yet understand it, so he installed the transducer wrong and didn't know to warn me about no depth reading at speed. However, his statement that I don't need to know how deep the water is when going faster than a troll shows, in my opinion, how easily he will stretch the truth to avoid responsibility. He is either an idiot or a liar. He did agree to install the fix hardware gratis; I pushed for that so he would be forced to come to grips with what it takes to get a depth reading at speed.

With Humminbird, I believe Humminbird could easily be considered guilty of fraud by omission, knowingly omitting information that is necessary for prospective purchasers to make good purchasing decisions and to avoid responsibility for not meeting reasonable expectations of their product.

Mosster47 reply :

On 5/10/2017 at 1:15 AM, Wayne P. said:

MEGA stands for the new Imaging frequency using 1.2 MKz or 1200 kHz either as a single frequency or CHIRPed from 1.150-1.275 MKz.

There are 5 models that have MEGA Imaging:

Helix 9 CHIRP MEGA SI GPS G2N

Helix 10 CHIRP MEGA SI GPS G2N

Helix 12 CHIRP MEGA SI GPS G2N

SOLIX 12 CHIRP MEGA SI GPS

SOLIX 15 CHIRP MEGA SI GPS

All of those also have 455 kHz and 800 kHz Imaging single frequency or CHIRPed.

I am not an employee or pro-staff.

I use their stuff and help others with their Humminbird units.

Wayne I was going to do an electronics overhaul this year and wanted to go all MEGA, but I don't want to run dual transducers.

Is the high speed issue with the MEGA units the same with the regular ones? I would be fine running the Gen1 versions. Ultra HD compared to HD isn't going to land me any extra fish.

Wayne P. reply :

On 5/10/2017 at 6:14 AM, MickD said:

Good, I now know exactly what mega stands for. It is as I understood it, but good to know I'm not missing anything. I was just curious about a Humminbird connection, Wayne, no offense intended. As I said before I've learned a lot from you and appreciate it. In fact I've learned much more from you than from Humminbird and my dealer.

I believe my dealer is just uninformed. This stuff is so new he just doesn't yet understand it, so he installed the transducer wrong and didn't know to warn me about no depth reading at speed. However, his statement that I don't need to know how deep the water is when going faster than a troll shows, in my opinion, how easily he will stretch the truth to avoid responsibility. He is either an idiot or a liar. He did agree to install the fix hardware gratis; I pushed for that so he would be forced to come to grips with what it takes to get a depth reading at speed.

With Humminbird, I believe Humminbird could easily be considered guilty of fraud by omission, knowingly omitting information that is necessary for prospective purchasers to make good purchasing decisions and to avoid responsibility for not meeting reasonable expectations of their product.

I think you are overstating the fraud deal. The units come with a transducer that does all the functions the units were designed for with a standard craft worldwide. No different than any other marine electronics company.

You may need to customize your installation for your craft and Humminbird has the accessories for that. It ain't rocket science, it's common sense.

Wayne P. reply :

On 5/10/2017 at 6:31 AM, Mosster47 said:

Wayne I was going to do an electronics overhaul this year and wanted to go all MEGA, but I don't want to run dual transducers.

Is the high speed issue with the MEGA units the same with the regular ones? I would be fine running the Gen1 versions. Ultra HD compared to HD isn't going to land me any extra fish.

PM sent with some stuff to consider.

MickD reply :

On 5/10/2017 at 6:36 AM, Wayne P. said:

I think you are overstating the fraud deal. The units come with a transducer that does all the functions the units were designed for with a standard craft worldwide. No different than any other marine electronics company.

You may need to customize your installation for your craft and Humminbird has the accessories for that. It ain't rocket science, it's common sense.

I respect your opinion, but disagree.

I have already customized my installation.

Common sense would be that when you pay over $2000 for new electronics on a $24000 deal, you would be able to do what you have been able to do with a $500 fish finder + the side imaging capability they are touting. The transducer does all the functions it was designed for, but not the common sense functions one would reasonably expect, like depth reading at speed. If Humminbird had said up front "this will not read depth at speeds over 6 mph" then I would have no complaint. I would either ante up to pay for the capability, or I would not. And I would have made the decision with all the info necessary, and would live with it.

Further North reply :

Mick, I'd challenge the fraud angle...and that the SI transducer cannot read 2D at speeds over 6 MPH statement...Looking around at other sites, I've seen that people have been able to get solid readings at 50 MPH.

Every install is different, even when the boat models are the same:

Distance from the keel
Different motor/prop
Different weight distribution in the boat so that the transducer is at a different angle
Skill of the installer
Full understanding of what it takes to get the transducer in contact with the water at higher speeds.
....lots of other "stuff".

There's almost no way Humminbird (or Lowrance, or Garmin, or anyone else) can account for those variables with their "standard" equipment.

Regarding your dealer...they sound like a buncha knuckleheads. Typical of "Sell it and get it out the door so we can sell more" kind of places. It's unfortunate...but there's a fair percentage that are like that...and if they are your local dealer...you're kinda stuck.

MickD reply :

From Humminbird.com support:

Side Imaging technology generally works best in speeds up to 10 MPH. This will vary depending on the boat hull and the location of the installation. Compact Side Imaging transducers like those that come with the 899ci HD SI are more conducive to faster speeds due to the smaller size.

While the standard 2D sonar built into the Side Imaging transducer will work to much higher speeds, high speed readings with the transom mounted HDSI and MEGA SI transducers on faster boats are often limited by the turbulence that occurs around the back of the boat. The HD and MEGA Side Imaging transducers are especially sensitive to this, due to their size, so we suggest the following solution.

The MS SI DB Y connects to the XP 9 20 (for all Side Imaging units, except ONIX, ION and SOLIX) and the AS 14 SI DB Y which connects to theXP 14 20 (for use with ONIX, ION and SOLIX). Both of these are Y cables that connect a dual beam transducer (for inside the hull mounting),and the Side Imaging transducer (mounted on the transom) to the unit."

Let me translate: "Side Imaging technology generally works best in speeds up to 10 MPH." What this means is that "Side Imaging technology does not provide depth readings above 10 MPH." Talk to a Humminbird tech as I have and that is what they will tell you. It is proven by the Humminbird-recommended transducer mounting height which is above the boat bottom surface, which puts it out of the water at speed. There is no possibility that a SI mega transducer can give depth readings at speed if it is not in the water. My transducer as originally mounted was in compliance with your 5th point-it was definitely in the water at speed. And it would not give depth readings above 6-10 mph. Your whole message is in conflict with what Humminbird says are the facts. To get depth readings at speed you need another transducer and a Y cable, about $100 + installation.

Let me know when you get your mega transducer to give you depth readings at speed. I am very interested, but not confident, you will ever get it to work. Neither is Humminbird.

Further North reply :

Mick...we may be talking about apples and watermelons here.

I don't expect (or want) SI depth readings above about 6 MPH. Pretty close to useless above that, IMO. Detail is lost at speed...

All I need at running speed is 2D depth readings.

I read the info you quoted from the HB website...but don't interpret "Side Imaging technology generally works best in speeds up to 10 MPH." to mean we can't get 2D at speed.

There are folks out there getting 2D at 50 MPH with this transducer. I may not be able to get there because of the shape of my hull, or other things unique to my install, but I'm betting that with some attention to detail and some fiddling around, I can get it to work at the speeds I normally run.

If not, I'll rig a 2nd transducer that I already own. Installation is free.

MickD reply :

I agree that all that is necessary and desired at speed is 2d depth. Not SI at speed. But you won't get that from the mega transducer according to Humminbird. It isn't even in the water at speed if it is mounted according to Humminbird instructions. And mine was mounted so it WAS in the water at speed, and it didn't read the depth at speed. The digital reading started at the true depth and as time at speed increased, the digital reading just kept increasing so that it read 99 feet in 8-15 feet of water.

If you get it to read by tweaking the height and position, good for you. I am interested in whether you can do it, so please check back in after you tweak it. Humminbird might be interested too because when you talk to their techs, they will tell you that you need the second transducer.

The 2nd transducer and Y cable is the robust solution as the signal for depth comes from that transducer, is "Y'd" into the unit with the Y cable, and the unit automatically reads the digital depth reading off that unit, no switching required. The solution works fine. That's what I have working now. My only worry is that the second transducer may "shade" the SI transducer since it is mounted lower. I don't have enough experience since installing to know.

Further North reply :

Got it working...in fact, it's working well enough that I'm getting SI images (lacking any useful detail, of course) up to about 33 MPH. I have a couple screen shots but haven't grabbed them off the card yet. Didn't feel like screwing with it last night.

Changed the angle a bit (back end up a smidge) and moved the entire transducer up about 1/4" - 3/8".

Further North reply :

...so...yes, the big transducer will work at speed, if you get it set right.

MickD reply :

Good for you, thanks for reporting. Can you tell me the approx height relationship of the transducer bottom surface to the boat bottom surface? Is the digital depth reading from the SI transducer? You should go to Humminbird and put on some seminars.

Further North reply :

On 5/16/2017 at 10:20 AM, MickD said:

Can you tell me the approx height relationship of the transducer bottom surface to the boat bottom surface?

I'll take a look tomorrow, try to get you a guess.

On 5/16/2017 at 10:20 AM, MickD said:

Is the digital depth reading from the SI transducer?

From the MEGA transducer, yes.

Full disclosure: I bought and mounted the other 2D only transducer, which worked fine. Then I adjusted the the MEGA to get it up as far as I reasonably could, and flattened it out a little...saw I was getting the SI images at speed...and unplugged the 2D to see what happened...you see the results.

Another thought: My boat, a 2005 Crestliner CMV, is pretty smooth at the back of the boat - no strakes, rivets or much of anything to disrupt the flow of water.

On 5/16/2017 at 10:20 AM, MickD said:

You should go to Humminbird and put on some seminars.

Nah, I'm far from the only person getting these results. It just took a lot of digging around, a fair amount of reading, some fiddling around with the transducer...and some luck.

Also, I'm a little stubborn...

Further North reply :

On 5/16/2017 at 10:20 AM, MickD said:

Can you tell me the approx height relationship of the transducer bottom surface to the boat bottom surface?

The inside corner (port side of a starboard mounted transducer) is just about exactly level with the bottom of the hull and the whole thing tilts down maybe 2°.

The boat (2005 Crestliner CMV 1850) has an 11° deadrise.

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MEGA SI issue 2024

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