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post #9 of Old 02-27-2007
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Originally Posted by rryan14
My requirements: I want a unit that has a relatively small footprint with a 5 to 8" screen with good resolution & definition in bright sunlight. Dependability and ease of use are also important. I donít intend to have multiple stations. I have been thinking of the (a) Raymarine A65 ~$1300, (b) yet-unreleased Garmin 540 5Ē high-res ~$650, (c) Si-Tex ColorMax Wide 7" ~$700, (d) Furuno GP1710C NavNet 7'' ~$900, and (e) Northstar 8.4" M84 ~$1400. The latter 3 all have the ability to add radar whereas the first two do not. There is large price range and features in this list. Money is an issue but I donít want to be penny-wise, pound-foolish later on.
I like Lowrance units. I bought a small (3.5") unit for my last boat and I will be buying a bigger unit (5") for new
newer boat.

The latest 5" units from Lowrance will support radar, there are units with and without sonar, internal and external antenna's, etc.

Lowrance units are very affordable (about $600 for a 5" high res screen with sonar).

Question 1: do I really need the combination fishfinder sonar to replace my DS? These seem nice but I don't care about fish. Stupid sub-question: does a GPS chartplotter display the chart's theoretical depth with sonar or do I have to have the dual frequency fishfinder sonar to display the depth?
You don't need the sonar but, IMHO, it's nice to have. I like to be able to see the bottom instead of just a number. With a decent sonar unit you can see what the bottom is (sand, mud, rock), and it's easier to see trends than just a number. On a Lowrance unit, sonar adds about $150 to the price (transducer, etc.).

The chart used in the plotter will determine if the charted depth is displayed or not. The better charts (that you frequenty have to buy, like from Navionics, etc.) will dispay the depth on the display. The base maps in the charter will probably not.

Question 3: Radar seems like a nice-to-have feature to me, whereas others would say it is more important than GPS in the cold waters on New England. How much more does the extra radar gear cost for the Furuno/Si-Tex/Northstar add (I couldn't get a straight answer out of the guys at Boston Boat Show)?
How far do you plan on sailing? Will you be out in all kinds of weather, or do you have the ability to stay home or in port in bad weather? For me, radar would be nice, but I don't plan on buying it. The Lowrance radar is $1 - 2K depending on power.

Question 5: Do these units get ripped off when the boat is at mooring? Should I install it so that it can be stowed away during the week?
Yes. The Lowrance unit I am familiar with takes about 10 seconds to install / remove.

Question 6: Is an external antenna necessary? The boat has a bimini that isnít used much. Most of the units require an external antenna and I am assuming that I'd replace the Loran antenna with a GPS one.
On your boat an external antenna is not required.

Question 7: How do you install the associated electrical, antenna, sonar, and radar cabling? Does it go through the pedestal or into the deck near the pedestal? Should I have a professional do this?
I was able to install mine myself. I'm handy, and do most of the work on the boat myself (engine maintenance, bottom painting, etc.). If you have never done electrical work you should probably not do it, or find someone with experience to help. It's not difficult, but does require some knowledge. Radar, IMHO, is something else entirely.

Lastly, IMHO, you should at least consider Lowrance.

Good luck,

Barry Lenoble
Deep Blue C, 2002 C&C 110
Mt. Sinai, NY

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