GT transducers have the down element tilted to port - how does that effect the image?

[Larry3215]

http://www.thehulltruth.com/marine-e...ansducers.html

Im still trying to work my head around this, and I still dont have all the information yet. Its coming in bits and pieces.

I dont know how bad this really is but I do know I dont like the implications one bit.

[TroyBoy30]

I tested every transducer offered by garmin and saw no difference in the original version and the current version. I could probably dig up comparison shots but the best i could do would be original gt50 vs new gt51

[Larry3215]

Id like to see those, but did you get any side by side shots of the same bottom? You really need to see the same bottom under the same conditions to compare properly. Comparing random shots might give you an idea of over all quality but wont show up detail differences - like exactly what "shadow effects" means. Shadows are an important part of interpreting SI and can effect details on DI.

Also, and possibly more important, Id like answers to my other questions - mainly is the 2D tilted as well?

If the 2D and DI are both tilted, then the transducer is going to show targets to port more than targets to starboard and could even miss targets that are under the boat in deeper water. It will make you think targets are under the boat that are really off to port and you will be mire likely to miss target to starboard.

Leveling the transducer is an important step in the installation. This built in tilt is not a good thing.

Id also like to know when Garmin started this and how to tell for sure if mine is titled and if Garmin has plans to change back to properly built transducers?

If your guy knew this much, he has to now about the 2D at least and when they started this.

[LWINCHESTER2]

The modification involved only one change, namely, changing the orientation of the linear transducer element from straight down to an orientation that is rotated 16 degrees off of straight down.Garmin refers to this linear transducer element design as the “tilt design.”

Upon information and belief, Garmin includes a linear transducer element having
the tilt design in at least the following products listed in Garmin’s 2016 Marine Catalog: the
Striker dv series (including specifically the Striker 4dv), the Striker 7sv, the echoMAP CHIRP
dv series, echoMAP CHIRP sv series, the GPSMAP xs series, the GPSMAP xsv series, and the
GSD 25 sonar module. See Exhibit C, pages 9 and 36-44. Except for the GSD25 sonar module,
these products use, inter alia, a head unit and a transducer with a linear transducer element as
well as a second, circular transducer element.

https://search.rpxcorp.com/litigatio...ments/11884099


On a different site with one of the Navico legal documents it reference some specifics as offending products in Navico's claims. The tilt design is described as tilt to port with the transducer intended to be mounted starboard.

GT-20 with tilt design
echoMAP CHIRP 74dv with GT-21 010-01524-01 shaded design
echoMAP CHIRP 73dv with GT-22
echoMAP CHIRP 53dv with GT-22
GT-30

[LWINCHESTER2]

This image was posted on THT and I copied it here. I'm not sure which GT transducer this would be. Notice the long rectangular lengths. They are not one single length but are three separate ones placed in line. This is likely the shaded array design. It's possible that different voltages could be applied to each or that a single voltage could be applied to all three in parallel as argued in the Navico case.

[Larry3215]

Thanks for finding that stuff! You have a lot more patience than I do reading court docs!

Im going to guess the circular element is the 2D element.

So from that, they started tilting elements at some unknown time before Mar 2016 and for all we know they are still tilting them. I would guess they still are. Its got to cost money to re-work the production line to accommodate that kind of change in element mounting.

That was a GT30 transducer by the way.

[Schins]

maybe its the one thats on every product box stating a new transducer design

[LWINCHESTER2]

That was a GT30 transducer by the way.

So it would be the shaded array variety, whatever that means. I did see in the litigation details that it said more power was applied to the center crystal than the other two and it had a different beam pattern than one single rectangular crystal would have. There was also quite a bit of discussion that the stepped array was a different mechanical configuration than a single linear element. I don't have a clue which transducers are the stepped array variety, but apparently some of them are. Nor can I speculate as to the performance advantages or disadvantages of shaded array or stepped array compared to the single linear element variety. I think it is obvious that they would be more expensive to build. You can see the side elements in the GT30 and they are also shaded array and don't have to be. Garmin licensed the SI technology from Hbird so those could have been single linear elements.

The way Garmin won the lawsuit really opens the door. Invaliding Navico's patent means that Garmin can use whatever they want to now. I hope they will take what they have accomplished with the GT50,51 & 52, meld it with the open door options they now have and also resolve the "Y" cable limitations to using only one transducer and come out with a new line incorporating the best of each. Maybe add a MEGA for the structure-philes. I would suggest a 360 Panoptix but who could afford it?

[Larry3215]

There are still questions to be answered. The 'shaded array' you're talking about is not the same thing that Troy's secrete agent was talking about in the other thread. Also, according to the secret aganet ALL current GT transducers are tilted to port.

The current production GT downvu transducers use a 3-pc array that is rotated to port side 16degrees. Provides a bit of shadowing effect without affecting depth performanc

and then he amended it to this:

The current production GT downvu transducers use a 3-pc Downward array that is rotated to port side 16degrees. Provides a bit of shadowing effect without affecting depth performance.
on the go

I want to know exactly what the "shadowing effect" is and what it looks like on the screen.

Id like to know exactly what the secret agent meant by "shadowing effects". What exactly are they? Is he talking about the ghost lines or waffling or something else?

Is one side of the SI going to be brighter than it should be or?

It also occurs to me to ask if a port tilt means the beam points to the port side or the starboard side? It occurs to me that if the boat was tilted to port, the beam would point more to starboard. The same could be said of a tilted array. The way things have been worded, it could go either way.

Id also still like to know how I can tell - for sure - if my transducer is tilted or not and if Garmin intends to keep doing this? When did they start doing this and when will it end?

[Larry3215]

We have all been told, since the very first transducer that was ever made, to be sure to mount them level side to side. Yet here Garmin is tilting the DI beam? That cant be a good thing, but we dont have enough information to begin figuring out how bad it is or how to possibly make allowances for it or correct for it when looking at the images.

[LWINCHESTER2]

It's hard to decipher this from the litigation. The public version has lots of redactions. Also not all public versions are the same; not that they are different but some are more lengthy than others. All I can say for sure on the tilt is what we've already been told. 16 degrees to port. If you are going to tilt it that makes sense as the recommended mount is on the starboard side of the boat. I have seen that the GT20 and GT30 and GT40 were made in both a non-tilted and tilted version. They are identified that way in the litigation. I have also seen that the GT50 and GT51 are shaded array designs that is claimed to be a superior design because that design has reduced side lobes.

For me, yes, I would like to understand the technical aspects as much as I can. Maybe I know how it works, maybe not. I do know I wouldn't trade my GT's for anything else out there. They are just better transducers in my book for how I fish. The best I can tell they work just like they did the first time I used them.

[TroyBoy30]

He's not a secret agent we both talk to the same guy. I simply haven't reached out since I sold my stuff, so I'm not sure how welcome my questions would be.

Buy an original gt and a current gt..take em apart or have them x-rayed and find out

[Tommy O.]

He's not a secret agent we both talk to the same guy. I simply haven't reached out since I sold my stuff, so I'm not sure how welcome my questions would be.

Buy an original gt and a current gt..take em apart or have them x-rayed and find out

You sold the Garmin equipment you had installed on your boat?

[TroyBoy30]

I did

[Larry3215]

I did

Im kind of slow reacting to this, but why???

You just put something like $10,000 worth of Garmin goodies on your boat just last year didnt you?

So, inquiring minds also want to know - what did you put on instead?

[TroyBoy30]

I ran garmin and panoptix for almost 2 years. I got the 7612's when they first came out. i was not totally satisfied with side or down images. my plan was to keep both garmin units and add 2 solix units in an attempt to build the perfect system. garmin for 2d, mapping and panoptix and bird for side and down at the console. at the last second i bumped up to the solix 15 and simply didn't have enough room on the boat for 2 15's and 2 12's, so im running 2 solix 15's. so now i have great down and side and crappy 2d im adding a ultrex and 360 next week to get a first hand comparison of the two offerings. I'm lucky enough to be able to try whatever I want so don't be surprised if I switch again if something new comes out now that the raymarine axiom pro is coming it should be a closer apples to apples with the 7600's, carbons and solix

you can see the pics here

http://www.bbcboards.net/showthread....hlight=stratos

[grout-scout]

I am shocked to read that Troy swapped back, I thought he loved the garmins.

[TroyBoy30]

you musta missed the long explanation above your post

i didnt swap back as i never left. i had bird units on the boat the entire time. i wish now i would have left the garmin on the bow and just put a solix on the console but i didnt want to do without networking

[Larry3215]

you musta missed the long explanation above your post

i didnt swap back as i never left. i had bird units on the boat the entire time. i wish now i would have left the garmin on the bow and just put a solix on the console [B]but i didnt want to do without networking[/B

Yeah, we can all dream that maybe one day all the mfg's will agree to a NMEA5000 standard where they can all share everything from every brand - transducers, sonar, maps, all accessories, control of trolling motors, etc etc etc. Then you could pick the individual parts that suited you best...... yeah right :)

By the way, when you say things like

and simply didn't have enough room on the boat for 2 15's and 2 12's,

it makes me hate you..... ;)

[TroyBoy30]