Moderated Discussion Areas
ContinuousWave: Small Boat Electrical
|Author||Topic: Raymarine A60|
posted 03-28-2008 12:23 AM ET (US)
I had a chance to bench test a Raymarine A60. We still have snow in the backyard--just got four more inches falling tonight--so no on-the-water trial.
The nicest feature: screen captures that can be easily transferred via a Compact Flash memory card, and even to a non-Windows operating system (like my MacOS machine). You definitely cannot say that about every electronic display device.
posted 03-28-2008 12:42 AM ET (US)
Regarding the scaled up images, the dot pitch of the A60 is figured like this:
If the diagonal of the A60 display is 5.7 inches, the sides are in a 4:3 ratio, and the pixels are 320 by 240, the dot pitch is:
For several monitors I checked the conversion worked out to a non-integer ratio for the scaling (between 1.2 to 1.4), and that made some of the images look awful on some browsers. So I changed to a nice, simple 3:2 ratio for the blow up. The results may be a bit larger on your computer than they were on the A60. It all depends on your monitor and display settings.
posted 03-28-2008 01:11 PM ET (US)
When I click on the link to see the web page of screen shot, I get to the web page "Dump0002". I click on the screen shot, it takes me to Google Maps, not Google Earth. Google Maps, in turn, does not show me the location where the screen shot was captured. Instead, it shows the whole Earth map, zoomed all of the way out.
Looking at the "Properties" of the screen shot, the address for the link is: http://maps.google.com/?sll=45.343201,-83.479713&z=0. It appears that the last set of characters is the zoom level, and if the 0 changed to 100, the map zooms in on the area associated with the coordinates in the screen shot. However, there is no pointer to exact spot of the coordinates. Can these items (i.e., the zoom level and the absence of pointer) be modified or corrected?
posted 03-28-2008 03:30 PM ET (US)
You'll have to ask Raymarine to modify the firmware of the A60 to change the way the .HTM file is created. I don't think there is any user handle on those parameters. [Also, you could tweak the .HTM file to add more parameters to the link. Or just use the meta-data in any way you like. My guess is that at some point there probably was a default zoom setting that gave a better result.]
Yes, GOOGLE MAPS, not GOOGLE EARTH--I'll make a correction.
Also, I found that the image files look far better if viewed on a Windows machine if you use SAFARI for the browser. It re-sizes the images without turning the text into gear-toothed glyphs.
posted 03-29-2008 08:46 AM ET (US)
Amazing that in 2008 a company like Raymarine sells a GPS without the WAAS feature. For fishermen WAAS is THE feature required.
They made a huge mistake when they failed to include the 125 antenna with the A-60 and many buyers were unhappy with them over that mistake.
Garmin, Lowrance and others had no problems with the satillite change which was announced yeras in advance.
posted 03-29-2008 10:31 PM ET (US)
Regarding the accuracy of a GPS position enhanced with WAAS versus one not enhanced, the following results are cited in a Wikipedia article:
GPS with SA off = 2.5 meter (8-feet)
In most boat navigation knowing your position with an error of less than ten feet is usually sufficient. If you are navigating in a situation where you need to know your position with an error of less than ten feet you are in some exceptional circumstances.
In the case of my boat, the GPS antenna is located on the starboard gunwale. This means the antenna is more than three feet off the boat's centerline and over 20 feet from the bow. If I were proceeding to a position and wished to have an error of less than three feet, it would be necessary for me to take into account the orientation of the boat relative to the GPS antenna. For example, I could be tied to a permanent mooring and as the boat might swing around the mooring, my position would change more than three feet. If I were navigating a narrow channel I would have to adjust my position if I changed direction 180-degrees by about 9-feet because of the change in the antenna location.
Without WAAS the typical position accuracy is about ten feet. That seems sufficient for just about any boating situation that I can imagine. I really don't think in open water I can control the boat with sufficient accuracy to get closer than ten feet to a position.
Sure WAAS would be nice, but it is not a deal breaker for most applications. WAAS was designed so you could make an instrument approach in an airplane. It's that accurate. I don't know anyone who comes to the dock and uses their GPS to make the approach.
posted 03-30-2008 08:12 AM ET (US)
Butch, interesting comment. I don't have WAAS and have no trouble finding structure and loading the coolers with fish. I feel that WAAS is nice but certainly no mandatory.
posted 03-30-2008 08:58 AM ET (US)
Wikipedia would not be my choice for definitive information. The accuracy cited, while obtainable under perfect conditions, is rarely seen in my experience while fishing on Mobile Bay.
Check the satellite status page on your GPS and you will find a position error number. The usual is far greater than 0.9 - 2.5 meters.
I agree that WAAS is often unnecessary to find or return to a fishing hole. It is a nice feature to get you so close that it is unnecessary to then use the sounder to maneuver dead onto the spot. Some fishing spots, especially over structure such as a wreck, can be difficult to find. While fishing it is often useful to get on the spot and stop your engine quickly in order to minimize spooking your targets.
posted 03-30-2008 11:33 AM ET (US)
Butch--You should feel free to cite another source for comparative accuracy of a GPS with SA off versus a GPS with WAAS. My mention of Wikipedia should not be construed as limiting you in any way.
Also, thanks for you anecdotal report of accuracy of a GPS being less precise than cited. If we are going to use anecdotal reports, then I will mention that during the time I was testing the A60 on my bench the device reported that its horizontal dilution of position (HDOP) was less than "2", which I believe means less than 2-meters. The user manual is a bit vague on this:
Source:Page 38 of A60 User manual
The general discussion of the accuracy of a GPS with SA turned off versus the accuracy of a GPS with WAAS enhancement is probably sufficiently complicated that it warrants its own thread. If you want to pursue it further, let's move to a new thread on that topic.
posted 03-30-2008 01:53 PM ET (US)
Over on the GPS sites, WAAS accuracy is generally accepted
at about 3 M, non-WAAS as about 15 M.
Raymarine's inability to handle the change in the WAAS birds
posted 03-30-2008 03:26 PM ET (US)
Another question: Why did you have to do all the Pythagorean
Theorem stuff to get:
H = 4.555
when a tape measure would be easier?
Also 70.1 pixels per inch would be 2.76 pixels per mm, which
posted 03-30-2008 06:16 PM ET (US)
I'll defer to Chuck on commonly accepted GPS accuracy being more in the range of 3 meters using WAAS and 15 meters with SA off without WAAS. Three meters seems to be the accuracy claimed by most manufacturers of WAAS units.
Three meters is about the length of my boat and it meets my needs quite well.
Of course, before WAAS I was delighted with the 60 - 70 feet or so of accuracy obtainable with a non-DGPS unit with SA on.
I admit it, I've become spoiled by my toys and would hate to be without them. I love my Lowrance LCX111CHD and would miss it if I had to give it up. It is especially wonderful in view of the close out price paid.
posted 03-30-2008 07:16 PM ET (US)
I am afraid I cannot defer to Chuck's citation of "the GPS sites" as the recognized authority on the accuracy of GPS systems. That seems a bit vague to me.
WAAS GPS performance is deemed sufficiently accurate to use to land a plane in low visibility at speeds of 150-MPH. Those parameters seem a little more demanding to me than getting back to the fishing hole or wreck site. Whether a fisherman or diver can make an argument that he MUST have WAAS enhancement on his GPS in order to make it useful is open for debate. And that debate would be a good topic on its own.
Also, let me repeat, the topic of the accuracy of GPS without SA versus GPS with WAAS is sufficiently complex that it warrants its own discussion, and I invite everyone who is an authority to join in a new discussion and inform us. But if you do, please use some citation that is more specific than "the GPS sites" for your reference.
As for how to deduce the sides of a right triangle when only the length of the hypotenuse and the ratio of the sides is given, I don't see any simpler way than the one I used. I don't have the A60 available to measure the display, but if anyone is really interested, just head down to your local marine store and measure away.
As for the correct units to use when discussing the pixel density of a display, I am sticking with inches, especially when the size of the display is stated in inches. The A60 display is described as being "5.7-inch," and it is just about universal that the size of marine electronic displays are described in inches.
I am sure the product marketing people at Raymarine would rather be able to tell customers that their device still has a WAAS enhanced GPS. I believe the price of the A60 has fallen recently, and it may very well have something to do with the WAAS situation. From a manufacturing point of view, the cost to add WAAS to a GPS receiver is probably very small, on the order of a few dollars I would guess, so it is hard to make any sort of justification for NOT having WAAS. You just throw it in with the rest of the package nowadays.
By the way, WAAS is applicable only in North America, and Raymarine sells their products all over the world. So while the US market is certainly important, the situation with WAAS does not affect Raymarine buyers outside of North America. WAAS never worked for them, either before July 2007 or after.
What I have found over a few months of looking at many marine electronic devices is that there is no clear leader in the price-value-features equation. There are many choices on the market, and people are buying a variety of different units and brands. There does not seem to be one particular brand or model that has emerged as a market leader or the most popular.
I'll repeat the observation that began this discussion--the A60 is a SONAR whose echograms can easily be recorded and transferred from the device to a non-Windows computer. This criterion may be more important to some users than the loss in accuracy that resulted from the WAAS change.
posted 03-30-2008 07:25 PM ET (US)
To assuage Chuck's worry about Raymarine's competence, they did provide firmware upgrades for some of their GPS sensor products in September of 2007. They just did not have a cure for the RS12 sensor.
posted 04-09-2008 08:33 AM ET (US)
Jim, I just bought the A60 and I'm about to install it on my Revenge 22 -WT. While I was looking at the better place to install the display (on the cockpit), I realized that there will be some problems:
1. Where to put the DSM25 sonar module? I think that the better location is on the back of the locker (I don't know the precise word) that is under the steering wheel.
2. How I will manage to let three cables with big plugs pass through the cockpit? This seems to be the bigger problem as if I drill a big hole in the cockpit, I must also be able to avoid water and humidity to pass through it.
PS I forgot to mention the GPS sensor location. I made some test placing the RS12 in different places and I discovered that a good location is just under the windshield on the port side. This place is not so close to the magnetic compass and is well protected from water and people walking on it. Surprisingly the Horizontal Dilution of Position value was 0.9, despite some obstacles represented by the windshield frame.
posted 04-12-2008 09:35 AM ET (US)
Thanks for the report on the RS12 GPS sensor's performance. It seemed like a sensitive receiver when I tested it on the bench.
I will reply to your other questions in another thread.
posted 04-14-2008 01:46 AM ET (US)
I went out yesterday for a short comparison test between Garmin 276c and Raymarine a60, having mounted the A60 without a definitive routing, but leaving the cables free.
The first impression is the incredible brigtness of the A60 display. In fact I cound see and read it perfectly even in open, bright sun light, while Garmin display needed a shady position to be visible.
Regarding the acouracy of the position, I could not be able to feel any difference, but it was a short test and Garmin was receiving EGNOS signals.
Raymarine is widely superior regarding strongness (I'm not sure about the word) as it has a metal support and stronger case anf keys, but the trackpad is a little hard to push and the result is that panning on the chart is much easyer with Garmin.
On one side Garmin is really superior, the availability of navigation data. I try to explain. When you follow a route and you have to choose wich data you want to display on the screen, Garmin offers a bigger choice and, very important, you can have DESTINATION ETE, ETA and DISTANCE. Ray marine gives only NEXT WAYPOINT ETE and RNG (distance). While cruising on a long route with many waiponts, DESTINATION data are important and I can't understand why Raymarine deliver only next waypoint data.
Despite this, I must say that it is clear that Raymarine A 60 is a nautical device based on essentiality, it has a wonderfull visibility (that is the firt quality of a marine display for an open cocpkit boat), hardware seems to be strong and fit for hard conditions. Garmin has good software gadgets, but when the conditions gets serious you simply can't use it as display is hardly visible.
posted 04-14-2008 07:41 AM ET (US)
PS: What is SA, I mean the phrase GPS with SA off?
posted 04-14-2008 08:46 AM ET (US)
SA is an acronym for Selective Availability. Selective Availability is an operational mode for the Global Positioning System (GPS) in which an intentional dither or variation is introduced which spoils the accuracy of the system for civilian Global Postioning System receivers (GPSr). Specialized receivers used by the military are still able to maintain accuracy when the GPS is in SA mode. The GPS has not been operating in SA mode for a long time. It is not anticipated that the GPS will return to SA mode.
When the GPS is in non-SA mode the horizontal position accuracy with a good receiver will be on the order of an error of 3-meters or about 10-feet. The vertical position accuracy will be about half that, or about 20-feet error. Vertical position accuracy is generally about half the horizontal accuracy, but as a mariner this is not of much concern--we are typically always on the surface of the sea. Vertical position accuracy is more important to aviators.
Your observation of the excellent visibility of the color display of the Raymarine A60 in direct sunlight is in complete agreement with my estimation of it. It is a very bright and strong display.
posted 04-14-2008 03:33 PM ET (US)
Tanhks again Jim for the explaination, I didn't know that modern GPS were SA free. Any way my experience tells me that 3 meters isn't the normal accuracy. As sometimes I cruise in the canals of venetian lagoon I can often see that my GPS (Raymarine and Garmin) show an error of 10 to 15 meters, while it is rare they show my boat with an error of 3 meters. I could experience the same projecting my gps tracks on Goggle Earth.
Regarding Raymarine A60 echo sounder, today I mounted the transducer in center position and I was happy to realize that it worked well. It was able to read the bottom at 24 knots, maybe with a little delay (but I'm not sure of this delay). I also mounted the gps sreceiver with a little pedestal on the port side of the cockpit and it worked great as HDOP was always below 1.0 when I was boating outside Venice without buildings around. In town HDOP was around 1.5 and 2.2.
I have some problems with my domain server and i can't upload my web site. As soon I will be able to fix the problem I put on line al the photos of the A60 mounted on my Revenge.
posted 04-14-2008 05:05 PM ET (US)
The position accuracy depends on many factors, and not necessarily related to the GPSr or its brand, although they can certainly influence. The particular arrangement of satellites and the lines of position available from them affect the accuracy. As you probably know from celestial navigation, each celestial body gives a line of position. If the vagaries of satellite orbits and your view of the sky permit, the GPS can give you a more accurate position in some cases, while in others, less accuracy is obtainable. If all the satellites you see are in one quadrant and close to each other, you probably won't get as much accuracy as if they were all nicely spaced at 120-degree intervals.
A great deal of complex mathematics has to be performed to deduce these positions, and the difficulty and wonder of it all has become a bit obscured from the view of the user. Sometimes we forget how truly "space-age" this technology really is.
posted 04-15-2008 08:08 AM ET (US)
Jim, I suppose you're perfectly right, moreover I believe that sometimes we forget that boating must be a way to find our natural and human limits, a chance to challenge with ourseves and not a video game.
On the other side I'm a little sad because a thousand of waypoints and routes that I have put on my old gps can't be transferred to my new and I don't want to cruise with two gps. Do you think there is a possibility to pass those wpt from Garmin to Raymarine using my Mac and Mac GPS Pro software?
posted 04-24-2008 05:00 PM ET (US)
I am having difficulty getting my new Raymarine A60 to give position information to my ICOM M402 VHF. The literature says that the Icom accepts NMEA sentences; RMC, GGA, GNS, GLL. The A60 apparently outputs: RMA and GLL.
The ICOM works well on my old Garmin GPS bit not on my new A60 plotter.
Any body have similar problems ??
posted 04-24-2008 11:30 PM ET (US)
First thing to check is "is the wiring right".
GPS NMEA + out (yellow) to VHF NMEA + in (center of the RCA jack)
GPS NMEA - out (brown) to VHF NMEA - in (shell of RCA jack).
And the GPS outputs the following sentences (amongst others):
posted 04-25-2008 12:29 AM ET (US)
I gave a list of the available NMEA-0183 sentences in the article which is linked in the initial post in this thread. There are 14 choices available including the sentence RMC.
The Raymarine A60 is rated as a NMEA-0183 talker. It should be simple to connect it to a NMEA-0183 listener. I don't believe there is anything in the A60 device which will prevent it from talking to a VHF Marine Band Radio which accepts NMEA-0183 input.
posted 04-25-2008 03:32 AM ET (US)
Thanks for the replies.
1) the wiring is correct. Also, I have put a multimeter across the outputs and there is a regular 2.5volt 'ping' every second or so.
2) in the NMEA output diagnostic screen, the A60 shows a position output every second on a scrolling screen.
2) to be clear, the A60 does not output GGA. It puts out RMC and GLL. Is this significant ?
3) I can find no setting for Baud rate in the manual nor the various menus.
-Do the various sentences clash in any way ? Which one should I prioritise ?
-Apart from 12v +and-, is there any other 'earth' connection to be made ?
I have a note from Raymarine Tech (in UK) as follows: << 04/24/2008 08:49 AM. Unfortunately you are out of luck as the A60/A65 transmit the $EC talker ID. As such, you are going to have to use another GPS sensor to supply data to the VHF or use one of our VHFs. In short the output data from the A65 is using the EC electronic chart) and not the GP (gps) identifier so the Icom will not see the data. >>
posted 04-25-2008 11:36 PM ET (US)
The sentences are standardized. The unit sending the sentence identifies itself in the sentence. It seem like the ICOM must be arbitrarily insisting that the GLL sentence can only come from a talker with ID "GP" and not "EC".
The GLL is the geographic position in latitude and longitude. It does not have to come from a Global Position Satellite. It could come from a LORAN unit.
posted 04-26-2008 12:04 AM ET (US)
This document explains more about NMEA sentences:
posted 08-02-2008 02:46 AM ET (US)
Having spent a couple of hundreds hours with my new RAymarine A60, I can say:
1. the unit has a great visibility
2. the sonar is really accurate and gives you data even at high speed (up to 35 knots)
1. The available navigation informations are insufficient. When you follow a route, the unit tells you only distance and time to go of the next waypoint without giving any information on the destination. This is a serious lack and I can't understand why Raymarine forgot to put this information on this unit, while Garmin delivers it even in the cheapest models.
Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.
Powered by: Ultimate Bulletin Board, Freeware Version 2000