From Bird to Garmin with Concerns

[jfishbones]

Recently purchasing my first Garmin, not installed yet, I have been calling Garmin asking them questions.
Being a Bird guy I always liked the fact that Bird knew fishing and sonars, its what they do.
Every time I call Garmin, while they mostly answer promptly and are very personable, their knowledge of their products seems very poor.
I ask them a simple question about their product and they have to reference a manual, or one guy even said "Let me check the website", or I need to ask and the person he asked did not know.
This is very concerning to me. I need technical answers on how certain products work and they cant answer my questions. Most recently it was about spec's on the PS21 vs PS31. Basically he said the only technical information they had was on the web site which really says very little and some of which I think is wrong, like the have the depth / distance at 300' for both unit yet one is 48W and the other is 144W.

I am truly not trying to disrespect them, I just get the feeling that us fishing guys are not their primary market and I don't feel comfortable spending my hard earned cash with a company that cant give me good information to help my purchase decision.

Am I the only one who has noticed this?

Honestly, I am thinking of returning my unit because of this.
I even asked about the Transducers TM52 that came with the unit, they could not tell me the coverage radius, just "Oh thats our best one because it's high and wide", what does that mean, how wide exactly?

I am hoping this was just a rarity because I really want to try the panoptix, but I have called them 5 or 6 times now and only had 1 person even relatively knowledgeable about their Marine products.

[ntslam]

the best advice I can give is always come here first when possible. The forums here are full people who use their units on a daily basis and are willing to share their knowledge from their own experience.

[LWINCHESTER2]

What you can find out depends on what you are asking about. Garmin guards the technical information on the Panoptix. Performance specifications are published but if you try to get into the details of how they do it, it's limited. It's called multi-beam phased array. Researching that, in time, will give you confidence that they can actually make it do what they say it will. It's a completely new concept to the fishing world. Many, perhaps most, still don't believe that through software control on a fixed mount transducer, that you can steer the beam and adjust the cone size or that it can look far from the transducer and determine both the distance and depth of a fish. I'm not sure how many Panoptix transducers there are now. The main ones are PS21 & PS31 (forward looking) and PS30 (down looking). I have all three and my personal experience is that Garmin marketing claims are more reliable than than competitor claims of performance. The technical information, in detail, is generally available.

Post your technical questions here. I believe you will get them answered. The one specific question you have posed was about the stated ranges. The range of the PS21 is 100ft and the PS31 is 300 ft. The website had this correct previously. Someone there apparently changed it and currently it is wrong. We regularly criticize Garmin for its website errors or lack of information.

You referred to the TM52 transducer. You likely meant GT52
The 2d is 150-240 Khz with the cone ranging from 24 to 16 degrees.
The 455 chirp on side and down is 2.0x50@455 and 1.0x30@800
The 2d is 250 watts and the side & down 350.

Here is a technical reference link on transducers:
https://www8.garmin.com/transducers/...guide-2015.pdf

Browse this site. Do searches. You will find a wealth of information.

[Astrochris]

Would you happen to know what the GT52 Q-factor is ? I have read in a few post about the Garmins low Q-factor transducers, but I have not seen an actual number for the GT 52.

thank you
C//

[LWINCHESTER2]

Would you happen to know what the GT52 Q-factor is ?

No, I do not know it or precisely how to calculate it.

To be called low "Q" I think that the number has to be around 2-3, but certainly not 6, 8, 10 or more.

The formula for calculating Q is the frequency divided by the bandwidth. That's fairly easy in a non-chirp transducer if you have access to the beamplots and certain graphs. Not so readily done on a chirp transducer but there are some indicators. Since the Q involves dividing the frequency by the bandwidth the wider the bandwidth the lower the resulting calculation. The bandwidth is readily available.

For example. The Airmar B75L spec sheets say it has a Q of 2. It's bandwidth is 40-75. That's a range of 35. See the attached pic from airmar. Pay particular attention to the peak performance range. That's what you don't see on non-chirp transducers. Now look at the P66. On 200 kHz they give it a Q of 37. Now look at the graph. The peak performance has very little range. The graphs for Figure of Merit may be more applicable but both illustrate the point that chirp transducers peak performance is over a range of frequencies and non-chirp transducers peak at a very narrow range. That range is a critical number in the Q calculation.

The GT52 range is 150-240 on the 2d element. That's a range of 90. That is a really wide range. Again, I don't know how the formula works here for choosing what frequency to use in the calculation but if it was 200, then 200/90 which would be just over 2. Worst case scenario would be 240/90 which is 2.67. Best case scenario would be 150/90 which is 1.67. So for any Garmin chirp transducer you could reasonably accurately calculate both the best case and worst case possibilities. So it is safe to say the GT52 is a low Q transducer.

Another point. I have not found that Garmin, Lowrance, or Humminbird misrepresent their products when publishing technical information. Sometimes you have to read closely what they say like Hbird cone angles measured at -10db instead of -3db that most everybody else uses. So 20 degrees Hbird is not the same as 20 degrees Lowrance, but it's still 20 degrees, the way they define it.

Having used the GT8, GT50, GT51, and GT52 I am quite confident that they are all low "Q". The test is to use them on a manual frequency setting at both ends of their range and see that the performance is still really good.

Sometimes we hear of a transducer having a "sweet spot", meaning a singular manual frequency that seems to do better than other settings, such as GT50 on 105 kHz. If we had the full technical specs, beamplots and graphs, you would be able to identify that by looking at that data.

[Larry3215]

LOL If you average your two calculations you get the exact number Garmin said. 2.76 + 1.67 = 4.34 /2 = 2.17 :)

No, I do not know it or precisely how to calculate it.

To be called low "Q" I think that the number has to be around 2-3, but certainly not 6, 8, 10 or more.

The formula for calculating Q is the frequency divided by the bandwidth. That's fairly easy in a non-chirp transducer if you have access to the beamplots and certain graphs. Not so readily done on a chirp transducer but there are some indicators. Since the Q involves dividing the frequency by the bandwidth the wider the bandwidth the lower the resulting calculation. The bandwidth is readily available.

For example. The Airmar B75L spec sheets say it has a Q of 2. It's bandwidth is 40-75. That's a range of 35. See the attached pic from airmar. Pay particular attention to the peak performance range. That's what you don't see on non-chirp transducers. Now look at the P66. On 200 kHz they give it a Q of 37. Now look at the graph. The peak performance has very little range. The graphs for Figure of Merit may be more applicable but both illustrate the point that chirp transducers peak performance is over a range of frequencies and non-chirp transducers peak at a very narrow range. That range is a critical number in the Q calculation.

The GT52 range is 150-240 on the 2d element. That's a range of 90. That is a really wide range. Again, I don't know how the formula works here for choosing what frequency to use in the calculation but if it was 200, then 200/90 which would be just over 2. Worst case scenario would be 240/90 which is 2.67. Best case scenario would be 150/90 which is 1.67. So for any Garmin chirp transducer you could reasonably accurately calculate both the best case and worst case possibilities. So it is safe to say the GT52 is a low Q transducer.

Another point. I have not found that Garmin, Lowrance, or Humminbird misrepresent their products when publishing technical information. Sometimes you have to read closely what they say like Hbird cone angles measured at -10db instead of -3db that most everybody else uses. So 20 degrees Hbird is not the same as 20 degrees Lowrance, but it's still 20 degrees, the way they define it.

Having used the GT8, GT50, GT51, and GT52 I am quite confident that they are all low "Q". The test is to use them on a manual frequency setting at both ends of their range and see that the performance is still really good.

Sometimes we hear of a transducer having a "sweet spot", meaning a singular manual frequency that seems to do better than other settings, such as GT50 on 105 kHz. If we had the full technical specs, beamplots and graphs, you would be able to identify that by looking at that data.

[Todd Driscoll]

The range of the PS21 is 100ft and the PS31 is 300 ft. The website had this correct previously. Someone there apparently changed it and currently it is wrong. We regularly criticize Garmin for its website errors or lack of information.

Leonard, sorry for the confusion. Actually, the website was incorrect before and what is posted now is accurate. The functional forward range of all Panoptix products is 300 feet. The 100 feet range refers to the maximum distance to detect your lure, whereas larger/harder objects like bridge pylons, brushpiles, and the bank/bottom can be readily seen out to 300 feet.

[jfishbones]

Leonard, sorry for the confusion. Actually, the website was incorrect before and what is posted now is accurate. The functional forward range of all Panoptix products is 300 feet. The 100 feet range refers to the maximum distance to detect your lure, whereas larger/harder objects like bridge pylons, brushpiles, and the bank/bottom can be readily seen out to 300 feet.

That sounds great Todd, thanks.
So with the PS21 I would get 45 degrees width angle and the PS31 I get a variable beam angle from 10-40, so max water coverage left to right is greater with the PS21 but you lose the 3D view?
What is the intent of having the PS31 angle variable? So you can reduce the cone angle to get a better sense of the objects true direction?

[Treeguyus]

Winchester best with technical information. Like Q etc. Comparing HB to Garmin. Have tried to get the cone angles from HB, difficult to get. High and wide means high chirp and wide coverage due to wide cone angle.

The techs have not used panoptix for fishing so they learn along with us all. Referring to a manual or website is necessary to insure the data they release is consistent. Garmins consumer base is huge, including navigation, ocean vessels etc.

Hope this helps. I have HB on my boats 800-900-1100, series. Besides Lowrance LCX's, Gen 2, Gen 3's find the Garmin easy to rig, navigate through the menus as compared to my other units. Don't have the new HB's so might be a unfair comparison.

Good luck a lot of people here to help you.

[Larry3215]

With highly technical questions, I find I get better answers if I email rather than call. Not always, but quite often, the support people will forward the email to the engineers/programmers and the answers will get forwarded back to you. Sometimes the engineers will respond directly back to you and you can then email back and forth with them directly without going through customer support. Its much slower though, so I always try a phone call first.

I agree with you it can be very frustrating when customer support doesnt know the exact answer to you questions, but I think you maybe could cut Garmin support a little slack. They have a LOT more equipment to handle than the Humminbird guys do and much of its a lot more complex in terms of features, functions, technology, networking, etc. In terms of shear numbers, Garmin has a lot more MFD's, transducers, radars, and other accessories just in the Marine dept. Plus they have all the other Garmin items like car GPS, handhelds, watches, etc etc. I cant imagine anyone knowing every detail about all of that off the top of their heads.

[jfishbones]

Thanks a lot for all the good information, its much appreciated.
On Panoptix, I have read a lot of good info on here and posted several questions with great responses :)

ON the Panoptix, I am trying to figure out which foreward view would be best for walleye trolling.
I thought I read the PS21 has a slightly wider cone but a cone that is not adjustable, and less power than the PS31 which concerns me for my application.
The wider cone would be nice since my boards are usually spread out up to 100' on each side but I was wondering how far ahead I can see with the lower power of the PS21 and what detail I may lose.

So to summarize, I am trying to figure out which unit would give me the best view width and distance for shallow water, less than 30', for my application so I can decide which unit to buy.

Thanks again

[Larry3215]

You will have to wait for the PS30 owners to answer about them. I only have the PS21.

Real world performance for me for seeing a single 12" trout or small bass or individual 12"-16' walleye is maybe 100-125 ft max. Schools of fish or larger fish like salmon can be seen as far as 150-180ft or so and large targets like seals to maybe 200 ft max. I can see bottom details, bridge piles etc to over 200 ft if the water is deep enough. Range is depth dependent just like with sideview.

Here are a few screen shots in salt and fresh water. I did not get any screen shots from walleye fishing(was too busy), but it worked just as well as trout fishing as far as range and seeing fish.

EDIT: I almost never run at max Gain, so you should be able to see further by tweeking settings.

[Larry3215]

I dont use planner boards, so I have a question. When you say you want to be able to see them, are you wanting to see both sides at the same time? Will the PS31 oe 21 be fixed or can you swivel it back and forth? How far behind the boat will they be?

Those details all make a difference.

Thanks a lot for all the good information, its much appreciated.
On Panoptix, I have read a lot of good info on here and posted several questions with great responses :)

ON the Panoptix, I am trying to figure out which foreward view would be best for walleye trolling.
I thought I read the PS21 has a slightly wider cone but a cone that is not adjustable, and less power than the PS31 which concerns me for my application.
The wider cone would be nice since my boards are usually spread out up to 100' on each side but I was wondering how far ahead I can see with the lower power of the PS21 and what detail I may lose.

So to summarize, I am trying to figure out which unit would give me the best view width and distance for shallow water, less than 30', for my application so I can decide which unit to buy.

Thanks again

[jfishbones]

I dont use planner boards, so I have a question. When you say you want to be able to see them, are you wanting to see both sides at the same time? Will the PS31 oe 21 be fixed or can you swivel it back and forth? How far behind the boat will they be?

Those details all make a difference.

Larry thanks for the screen shots.
PS21 or PS31 will be mounted on trolling motor, bow mount.
I mentioned boards, not wanting to see them but rather see whats coming into them up front.
I am probably not explaining this well but if the boards are 200' wide, both sides, it would be nice to see with panoptix forward whats coming into that 200' wide path I am trolling into, make sense?

[Larry3215]

Larry thanks for the screen shots.
PS21 or PS31 will be mounted on trolling motor, bow mount.
I mentioned boards, not wanting to see them but rather see whats coming into them up front.
I am probably not explaining this well but if the boards are 200' wide, both sides, it would be nice to see with panoptix forward whats coming into that 200' wide path I am trolling into, make sense?

You're going to have to scan back and forth to cover a 200 ft wide span of water with either the 21 or 31. A 40 deg cone angle doesnt reach a width of 200 ft until you are about 275 ft in front of the boat. Thats at the very far end of the range, plus the outer edges will be at the lowest signal strength on top of the distance because it will be the far sides of the beam. I doubt you would see and fish that far out, even if they were in the center directly in front of the boat, unless is was a big school of something.

I think your best bet would be a PS30 with the beam angled forward as far as possible. It has a 120 deg beam width. That would be 200 ft wide at a distance of just under 60 ft. You are much more likely to see some fish at that range, but your still going to be at the sides of the beam with the weakest signal. The beam will also be angled down to some degree, but I have no idea how much. That means the boards would have to be running at some depth to be seen - I think. I dont know the beam vertical angles on the PS30 so I cant calculate those numbers very well.

Over all, I think you would probably be better served by scanning from side to side with the 21 or 31 if you want to see what up ahead at a greater distance. That is going to be dificult if they are on the trolling motor, so maybe the PS30 would be better?

Thats why I have my PS21 on a separate stick - so I can turn it without having to turn my trolling motor.

[Larry3215]

That must mean the range is a matter of the technology rather than power?

[Todd Driscoll]

I need technical answers on how certain products work and they cant answer my questions. Most recently it was about spec's on the PS21 vs PS31. Basically he said the only technical information they had was on the web site which really says very little and some of which I think is wrong, like the have the depth / distance at 300' for both unit yet one is 48W and the other is 144W.

Support was correct when they provided the above info.

That must mean the range is a matter of the technology rather than power?

Exactly.

It gets pretty complex regarding all the beam widths involved. I've talked with the Panoptix engineers, and we will try and provide some additional details (possibly a diagram) that will make the power/range/beam relationship of Panoptix easier to understand relative to the PS 21 and PS 31.

[Larry3215]

One of the guys on THT just calculated it at around 2.17

http://www.thehulltruth.com/marine-e...ml#post9883471

From Garmin engineering:

The Q for the GT52HW chirp disc is 2.17. Q = Fc/bw.
Where Fc is the center of the band and bw is the total bandwidth.
Fc = Flow + bw/2. bw = F high - Flow.
So bw = 240-150kHz = 90kHz. Fc = 150 + 90/2 = 195kHz.
Q = 195/90 = 2.17.

[Treeguyus]

too much information....sorry...go out and fish with is the best

[azbohunter]

too much information....sorry...go out and fish with is the best