GPS / Sounder Deal

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Frank C

Post by Frank C »

Frank C wrote:Buy a digital, auto-setting, stick-on clock for the pedestal,
and label it "People time."

Set the GPS to permanently remain on PST,
and label it "Boat time."
That meager attempt at humor was a TIC comment ... without a genuine attempt at assistance.
[ insert here - M.Prouty cartoon of TIC (tongue-in-cheek) commentary ]
I understood your dilemma, just had no meaningful contribution. :|

Now that I ponder it, forget DST and just consider timezones. If you can find a stretch of coast vs islands that's bifurcated by a timezone, what's the ideal answer you'd want to see? (Forget for a moment that timezones are probably designated to avoid this scenario).

The GPS clearly recognizes the precise line along which the timezone changes. Tidal level at two locations, only 50 yards between them, must be identical. But the time at each location differs by one hour. How would you want the GPS to inform you .... prolly with a line for the timezone? Otherwise, the Skipper wouldn't know WHAT the darn thing is doing! And just as significant, the Skipper wouldn't know when he has changed zones. (not to be confused with the fourth mode under sail!)

Now complicate this scenario with daylight savings differences, which are subject to jurisdictional changes. What would you like to see on the screen? And is it realistic for the map-maker to manage it?

Maybe zulu IS best! Then it is the Skipper's job to interpret his offset from Greenwich ... :?: :?: :?:
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Post by Catigale »

Duane - I think thats why ZULU is used seriously for this very reason..

In the Northeast there is a $15 book called Eldridge's Pilot Guide which is just full of information on tides from Maine to NYC...and all kinds of rules of thumb for coastal tidal navigation.

Is there something like that for the Sound?
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Duane Dunn, Allegro
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Post by Duane Dunn, Allegro »

Your correct that zulu is used for all serious operations. We run a number of our servers here on zulu time just to avoid these issues. Everything in air transport is zulu based and all the GPS availabilty predictions we produce for the airlines is done in zulu time.

I also have plenty of tides and currents books to refer to, but I want the real time on screen info at the pedestal to be correct. I don't have any split time zone issues up here so I think manipulating the time zone may be a way to solve the problem. The real question is if changing the system timezone causes a change in the tide and current data being read from the Navionics chip. These measurement locations obviously know where they are and what time zone they are in. Since the system config change of turning off DST had no effect I think I may find that changing the system time zone has no effect either. They may have a hard coded offset from zulu to use in the database. They get the zulu timecode as part of the GPS signal and may just work off that without regard to any of the system local time parameters.

I should have some time tonight to play.
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Duane Dunn, Allegro
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Post by Duane Dunn, Allegro »

I've sorted out the tides and currents issue. They have a bug in the plotter software. The Navionics embedded tide and current table information that pops up on the map displays and the detailed displays reached by pressing the 'WPT' button do not correct for DST even when it is set in the system options. This will cause all the pop up tide and current info to be 1 hr behind and it cannot be used.

To work around this, go into the set local time settings and turn off DST rules, then select the local time and change it to be 1 hour ahead. In essence you have changed the time zone but this is not how it is reflected in the dialog box. You simply select the hour number and increment it up by one.

The Navionics embedded tide and currents popups and detailed displays will now match perfectly with the published NOAA tables which have been corrected for DST. If you happen to be out in the winter when we are not using DST don't forget to change the local time so the information displayed on the screen is correct.
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Duane Dunn, Allegro
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Post by Duane Dunn, Allegro »

Email exchange I had with Lowrance regarding the issue.
Thank you for your response,

We appreciate you sharing your thoughts in regard to this. We here at Lowrance are always interested in the needs of our customers and we really appreciate your suggestions. We will see that your e-mail is presented to the necessary departments. At this time we are not sure what exactly will happen to correct this issue. You can always log onto www.lowrance.com for information about new products and software.


Thank you for choosing Lowrance Electronics,

Lowrance Customer Service
12000 E. Skelly Dr.
Tulsa, Ok. 74128

Customer Service: 1-800-324-1356
Lowrance Website: www.lowrance.com

LEI Extras: Parts & Accessories 1-800-324-0045 online at www.lei-extras.com
-----Original Message-----
From: "Duane Dunn"
Received: 8/25/2006 6:36 PM
To: "'Lowrance GPS'" <lowgps@lowrance.com>
Subject: RE: Eagle GPS Question [254162:218799]

I did find a work around that corrects the time display in Navionics
Gold+ tides and currents.

- I turned off DST in the local time settings.
- I then selected the local time and incremented the time by an hour.
In essence I changed to a time zone one hour later.

This corrected the tides and currents information. The popup tide
heights and the current arrows now display the proper tide heights;
and current directions and speeds. The detailed daily tables now have
all the correct high/low and slack/peak times according to my official NOAA tables.

Obviously this puts a manual element into the tides and currents
depending on what time of year you are referencing the information.
You now have to manually keep the local time in sync with DST or
Standard time. Even so, at least now the on screen data can be used.
When it was one hour off during DST it was useless and in some cases dangerous if relied on.

I would suggest that you add this work around to the FAQ section of
your website so future users can solve this problem.

Do you expect to release a software fix for this issue?

Duane Dunn
-----Original Message-----
From: Lowrance GPS [mailto:lowgps@lowrance.com]
Sent: Friday, August 25, 2006 1:04 PM
To: duane dunn
Subject: RE: Eagle GPS Question [254162:218799]

Thank you for your inquiry.

This is an issue that has popped up occasionally and has recently been
brought to our attention. We are presently working with Navionics to
work out a solution to the issue. Thank you for your understanding in
this matter.

Thank you for choosing Eagle Electronics,

Eagle Customer Service
1200 E. Skelly Dr.
Tulsa, Ok. 74128

Customer Service: 1-800-324-1354
Eagle Website: <http://www.eaglesonar.com/>

LEI Extras: Parts and Accessories 1-800-324-0045 online at
<http://www.lei-extras.com/>

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Bobby T.-26X #4767
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Post by Bobby T.-26X #4767 »

Ok...i figured it out. how to thread the large ended cable connector thru a small opening.

Image

the cable end looks similar to this with the large outer knobbing (couldn't find an exact pic of it).

What i'm going to do is "grind" down the "knob" around the fitting on the cable end that connects to the GPS mounted sensor end.

the knob is currently a bit over .75" in diameter.
when the knob is ground down around the end fitting it'll be .5" which will allow me to easily thread thru the Stainless Steel railing.
I'll cut a hole in the plate that connects the railing to the Mac fiberglass side and route the cable thru there. then to the units.
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Post by Captain Steve »

Got mine installed yesterday...amazing visibility in full sunlight. Now just waiting for those spreaders to arrive!!!
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Post by Captain Steve »

Duane, Bobby what datum did you set your GPS/Chartplotter too??
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Bobby T.-26X #4767
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Post by Bobby T.-26X #4767 »

steve:
i'm not there yet :(
hope to be there soon.
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Duane Dunn, Allegro
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Post by Duane Dunn, Allegro »

All US marine charts use the default, NAD83. You don't need to change anything.
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Bobby T.-26X #4767
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Post by Bobby T.-26X #4767 »

finally mounted and set-up. have run and hidden all lines. checked out the GPS and it's works great.'
will mount the speed sensor and depth transducer on the transom tomorrow.
Captain Steve wrote:I am mounting both the sonar and speed sensors on the starboard side....away from the ladder and feet.
Steve: i'm doing it the same way as well.


i still need to do the final routing up the inside of the arch for the GPS sensor. have drilled the preliminary holes and it does fit (snugly) inside the 1" stainless steel tubing thru the fiberglass sides so the black cord is completely hidden. then the GPS cord connector comes out at the top of the Arch where the GPS sensor is located. very professional install (if all else fails in my business career, i can do this).

very, very cool unit.
$700 poorer, but could have never afforded a unit this nice. that is, the Lowrance replacement value must be over $1300.
thanks for the heads-up Duane.

Image
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Duane Dunn, Allegro
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Post by Duane Dunn, Allegro »

More Info, I received my NDC-4 cable today (It only took almost 2 months to get here as it was on backorder.) Opened it up, and was confused. I expected that it would insert between one of the cables and the unit. Not so. I also guessed that the NMEA 183 signals were on one of the wires in the power/sonar plug. That's not correct either. No wonder all my experimenting with jumpers in that plug couldn't find a combination that worked.

The cable goes on the one labeled "Accessory Socket" on page 28 of the manual. This is the outlet already in use by the speed through water sensor. This sensor must send NMEA 183 data to the unit. So now the trick is to open that cable up and sort out the wires.

If we're lucky it will have a orange and a black wire since orange is suppose to be NMEA receive. There may even be a yellow in there which is NMEA send. If that's the case I don't really need the NDC-4 cable, I should be able to just hook up the autopilot to yellow NMEA send and the black ground. If there's no yellow in the speed sensor cable, I guess I'll plug in the NDC-4 cable and then hook up the Speed sensor to the orange and black, then connect the autopilot to the yellow and black. Either way it looks like a little soldering will be needed.

I'll trace out the colors to the pins and post a picture here. The plug has 4 female pins but there are only 3 wires on the other end, so one is not used.
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Post by Captain Steve »

Thanks, Duane...still waiting for my cable
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Captain Steve
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Post by Captain Steve »

Duane, what was the outcome of your wiring set up? My cable is in!
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Post by Captain Steve »

Any others have advise on hooking up the wire to the radio to feed the lat and long to it?
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