Dummies Guide to GPS and Chartplotters

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Miles
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Dummies Guide to GPS and Chartplotters

Post by Miles » Sun Dec 11, 2011 11:19 pm

With the rate at which the human race is evolving, so too is the electronic instruments we use to help us in everyday life. The problem is that the sheer diversity of products available today, makes it a very daunting task for the novice boat angler to choose the correct navigational instruments for his application. To complicate matters even more, you have so much technical jargon that is used as advertisement, it just confuses the first time buyer even more.

With this thread, I’ll try and simplify the process of buying electronics for your boat, so that YOU can make a better, INFORMED choice.

What is GPS?

GPS stands for GLOBAL POSITIONING SYSTEM. GPS is a space based satellite navigation system, which gives you PRECISE location data ANYWHERE on earth. It was developed by the USA’s Department of Defence in the 1970’s and uses 24 satellites orbiting the earth. That’s pretty much ALL that you need to know!! If you’re intrigued by just exactly HOW it works, google it!! Loads of information on it!!

What advantages does a GPS hold for the novice boater?

With a GPS, you can MARK your harbor that you launch from. This will allow you to return to that harbor, should thick mist or fog obscure your vision, or in the dark where you can’t see land marks. From a safety point of view, a GPS is an essential piece of electronics if you regularly fish at night or in foggy/misty conditions. RAIN is also a situation which causes you to lose your sense of direction, as you will not be able to see land or any other land marks, which will be covered in cloud and obscured by the rain.

From a fishing perspective, a GPS will allow you to MARK reefs or any other area’s that hold good fish, so that you will be able to return to that EXACT spot again.
GPS will show you the DIRECT route to your selected destination. It does NOT take into account shallow reefs or any other dangerous navigational hazards. It merely shows you, in a STRAIGHT line, the quickest way to your selected destination.

To illustrate this point, look at the map below. If you wanted to go from Gordons Bay to Hout Bay, your GPS will show you a straight line route, right across the mountains!! You will therefor still have knowledge of your area you intend to fish, so that you can take into account all navigational hazards.

Image


If you do purchase a GPS, remember, they usually work of penlight (AA) batteries and some models run through batteries rather quickly. To prevent this, I would recommend buying a external power cable which can be used to power the unit. Another essential extra is a mounting bracket for your hand held GPS. It will protect your unit from falling and will allow you easy access to the unit.


What is a CHARTPLOTTER?

A chartplotter is an instrument that integrates the GPS data and a navigational chart. Instead of seeing the image as shown above, you now see an image with all the relevant data, such as water depth, navigational hazards, lighthouses, harbours, contour lines, shallow reefs, islands, etc.

Image


Your chartplotter will now show you your boat ON the map on the screen. This will allow you to track your progress as well as show you how close you are from navigational hazards.
The beauty of the chart plotter is that it shows you most fish spots, including their names, as well as all the harbours. This allows you to fish from harbours that you have not yet fished from, knowing where all the danger spots are!!

Lets say that you’ve just started out boating and hear that there is fish on Rocky Banks. You can now quickly check on your chart plotter and it will show you exactly WHERE Rocky Banks is. Now, lets say that you’re launching from Hout Bay. The chart plotter will show you where the dangerous area’s are, like South West Reefs, Bellows and Anvil. You can now navigate the area like a professional, as you have all the information at your finger tips!!

Chart Plotters are considerabily more expensive than GPS’s. They are also sold WITH-OUT the necessary charts, which means you need to buy the charts for YOUR area of operation. Charts range from R1500 to R3000+, depending on what charts you buy and for which area. Some charts are sold on SD cards, whilst others are sold on micro SD cards, whilst others have to be downloaded to your chartplotter, all depending on what unit chart plotter you have.

There are chart plotters to suit the needs of everyone. From small entry level units all the way through to big 15inch+ screen units. They all pretty much do the same job though!!

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Re: Dummies Guide to GPS and Chartplotters

Post by Miles » Mon Dec 12, 2011 12:09 am

GARMIN

Garmin is the benchmark against which other manufacturers are compared with. They make VERY good GPS's and Chartplotters and have been seen as the market leader for some time. The other manufacturers haven't been resting on their laurels and some of them are equalling and even surpassing Garmin in the chartplotting arena!! Furuno has brought out its NAVNET 3D systems and Lowrance has stormed the market with their HDS systems some time back, with even newer products coming out each season.

Garmin offers excellent products which are very user friendly (read: EASY TO USE!!! :mrgreen: :mrgreen: ), very reliable and they offer superb back-up support. Their prices are also very reasonable.

Lets start off by looking at the Garmin Range:

Chartplotters

400 series. All the units in this series offer a 4" screen. They are offered in both chartplotter as well as chartplotter/fishfinder combo's. The chartplotter/fishfinder combo is denoted by the letter "S" at the end of the model number ( S - stands for SOUNDER). The most popular unit is the 421 or 421S. Small and compact and not very expensive. Suitable for most smaller boats or those with a smaller budget. It uses the G2 vision charts. It has an internal aerial, which makes for a very easy installation (only the power cable to connect!!)

The screen is however quite small if you buy the chartplotter/fishfinder combo (421S), especially when you split the screen.

Prices range around R4500-5000 for the 421 and between R5000-6000 for the 421S EXCLUDING transducer. Both models need the G2 Vision Charts to be purchased seperately.

Image


500 series. These units all have a 5" screen and is also available in both chartplotter and chartplotter/fish finder combo. They also have built in antennae.
The popular models are the 521 or 521S and the 525/525S. The only difference is that the 521 has a QVGA screen (Quater VGA) whilst the 525 has a VGA screen (Full VGA), which means a better picture on your screen.

Expect to pay roughly R7000 for the 521 and a little more for the 521s PLUS the transducer. G2 Visions charts will also need to be purchased.

Expect to pay roughly R9000-10000 for the 525 model excluding charts.

521
Image


525
Image



Garmin GPSMAP620

This is a dual use unit. It can be used in your car as a normal car GPS unit and on the boat!! It has a 5.2" TOUCHSCREEN and also has a built in antennae. You can EITHER use the G2 Vision charts or the more affordable, BLUECHARTS. It does not offer a fishfinder combo unit.

Expect to pay roughly R7000-8000 excluding charts.

Image


700 series. This is garmin's touchcreen model. It offers a 7" touchscreen and also has a built in antennae. It also offers a RADAR plug in capability. BRILLIANT machine!!! :mrgreen: :mrgreen:

Expect to pay R 14000-15000 for the 720 excluding charts and roughly the same for the 720S excluding transducer and charts.


Image


Now come the big units. These multifunction units are sold as chartplotters ONLY. They require sounder modules should you wish to use the fish finder and require a radar which simply plugs into the unit, if you need one!!

4000 series. This range comprises of the 4008 (8" screen), 4010 (10" screen) and the 4012 (12" screen). A few years ago, this was garmins flagship models. They are being phased out, as they've been replace by the 6000 series. AWESOME units none-the-less. They have external antennae, which means you need to mount the airial.


Image


5000 series. This is the same as the 4000 series. The only difference being that it has a touch screen instead of buttons!! It is also available in a 15" screen model, the 5015.

Image


Garmins latest flagships of their range, the 6000 and 7000 series have only been around for a short time. I actually don't even know anyone who has one, so can't really say much on them at this point!! BUT, with Garmins track record, i'm sure they too will be brilliant units!! :mrgreen: :mrgreen:

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Breads
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Re: Dummies Guide to GPS and Chartplotters

Post by Breads » Wed Oct 10, 2012 2:36 pm

When should one use the 50kHz frequency? I've always had mine on 200, and don't know if I've been missing fish?
From what I understand 50kHz is for deeper water, but would you really use it when for example looking for tuna - seeing that you really looking for marks in the top water?
I've got the moves like Jagger

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Deon Seaport
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Re: Dummies Guide to GPS and Chartplotters

Post by Deon Seaport » Wed Oct 10, 2012 2:42 pm

Breads, jy kan hierdie link volg, Miles het dit mooi verduidelik en ek dink dit hoort jou te antwoord:
http://boatfishing.co.za/viewtopic.php?f=65&t=603
I live with fear, but she lets me fish once a week !

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Re: Dummies Guide to GPS and Chartplotters

Post by Breads » Wed Oct 10, 2012 3:10 pm

Thanks Deon, ja dis wat ek gesoek het.
As ek reg verstaan dek die laer frekwensie 'n wyer area, maar die detail is nie so skerp soos 200kHz nie.
I've got the moves like Jagger

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patrys
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Re: Dummies Guide to GPS and Chartplotters

Post by patrys » Thu Oct 11, 2012 7:19 am

as always. great post miles.
in my life God comes first, fishing second, fishing gear third and the wife and child have to fight between fouth and sixth

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