I'm a newbie to boat electronics, so I'll apologize up front for some
basic questions.

I've got a 32' flybridge sedan that I use on Lake Lanier in Georgia
(lake is about 140 feet deep, max). I currently use a handheld Garmin
GPS 76 for navigating, an old Hummingbird fishfinder on the transom and
the original depthfinder on the flybridge (kind of a "Rube Goldberg
goes fishing" setup). It's time to replace the depthfinder and I'm
going to consolidate and upgrade to either a Garmin 178c or a Lowrance
332c. My greatest need is a good depthfinder / fishfinder component.
The GPS mapping feature is secondary (after all, I'm on a lake) - I
really only need guidance home when the rain and fog rolls in and I
can't see my landmarks. I favor the Lowrance based on the comments I've
read on the quality of the sounder and the availablity of Navionics
maps, but any thoughts you have would be appreciated.

Here's my real dilemma. I want to put the new GPS/sounder unit on the
flybridge and use my laptop on the lower station when the weather is
nasty.

1) Can I direct cable from the GPS/sounder to the laptop, or will I
need a multiplexer? I'm going to use an old IBM laptop that has two USB
and one 9-pin serial connections. Even if I can direct cable, will the
use of a multiplexer improve the ease of installation and/or the
stability of the connection?

2) Can the setup be configured for the laptop to function as a second
screen replicating the GPS/sounder screen (similar to adding a second
monitor to a computer)?

3) If the answer above to 2) is no, which PC-based chartplotting
program(s) will display the depth and speed from the sounder as an
overlay on the GPS navigation map on the laptop screen - or must I
toggle between two seperate screens on the laptop?

Thanks in advance for your help.

1) Can I direct cable from the GPS/sounder to the laptop, or will I
need a multiplexer? I'm going to use an old IBM laptop that has two USB
and one 9-pin serial connections. Even if I can direct cable, will the
use of a multiplexer improve the ease of installation and/or the
stability of the connection?

You do not need a multiplexer to connect one single device to your computer.
The only benefit of using for instance a MiniPlex-Lite (3 inputs, one if
which can run at 38400 baud for AIS receivers) is that you have 2 spare
inputs for future expansion, it gives you galvanic isolation and it plugs
into your USB port while the supplied driver blocks Windows' Plug&Play
behaviour, so Windows does not see your GPS as a mouse (jumping cursor).

2) Can the setup be configured for the laptop to function as a second
screen replicating the GPS/sounder screen (similar to adding a second
monitor to a computer)?

No. The serial port only outputs GPS and sounder data, no screendumps. So if
you want somthing like this, you end up with option 3.

3) If the answer above to 2) is no, which PC-based chartplotting
program(s) will display the depth and speed from the sounder as an
overlay on the GPS navigation map on the laptop screen - or must I
toggle between two seperate screens on the laptop?

I don't know all the details of the various nav programs, but almost all
offer an extra window on top of the on-screen chart that shows data like
wind, speed, depth etc.

Meindert
www.shipmodul.com

This is just what I needed. Thanks!

Any thoughts on navigational software for the laptop? Ease of use is
important, cost is secondary.

On 13 Jul 2006 15:14:14 -0700, wrote:

I'm a newbie to boat electronics, so I'll apologize up front for some
basic questions.
snip

Here's my real dilemma. I want to put the new GPS/sounder unit on the
flybridge and use my laptop on the lower station when the weather is
nasty.

1) Can I direct cable from the GPS/sounder to the laptop, or will I
need a multiplexer? I'm going to use an old IBM laptop that has two USB
and one 9-pin serial connections. Even if I can direct cable, will the
use of a multiplexer improve the ease of installation and/or the
stability of the connection?

If you have a single talker (the GPS), there is no need for a
multiplexer. A multiplexer is used when you need to combine NMEA data
from two or more sources.

2) Can the setup be configured for the laptop to function as a second
screen replicating the GPS/sounder screen (similar to adding a second
monitor to a computer)?

No, if "replicate" means "show an exact copy".

3) If the answer above to 2) is no, which PC-based chartplotting
program(s) will display the depth and speed from the sounder as an
overlay on the GPS navigation map on the laptop screen - or must I
toggle between two seperate screens on the laptop?

There are a number of chart display programs available, from free to
very expensive. Two listed on my GPS/NMEA site below are Ozi Explorer
and Sea Clear - Sea Clear is free, and will display the BSB-format
charts that are used by most other marine chart programs. Ozi is
inexpensive, and will display BSB charts, or maps in many other
formats - you can even scan and calibrate your own paper maps for use
with Ozi. Ozi will show depth sounder readings, but only as a digital
reading, not as a graphic chart.


Thanks in advance for your help.

--
Peter Bennett VE7CEI
email: peterbb4 (at) interchange.ubc.ca
GPS and NMEA info and programs: http://vancouver-webpages.com/peter/index.html
Newsgroup new user info: http://vancouver-webpages.com/nnq

Thanks for the help - your website has lots of useful info. OziExplorer
looks like what I need.

wrote:

This is just what I needed. Thanks!

Any thoughts on navigational software for the laptop? Ease of use is
important, cost is secondary.

I use SeaClear II occasionally and it is truly a wonderful donation to
the public domain. SeaClear is best when used with a mouse with a
scroll wheel, otherwise the zooming and panning control are a little
hard to get used to.

If I were going to buy a navigation software today without any regard
for the cost I would purchase Coastal Explorer:

http://rosepointnav.com/CoastalExplorer/Version1_1.htm

I've tried it in the trial version and really found it to be a well
designed product:

http://rosepointnav.com/CoastalExplo...al/default.htm

There are some limitations on the trial version but they are reasonable
enough to let you get a full, although brief, trial of all the features.

Both SeaClear II and Coastal Navigator will use the free NOAA raster
charts. Coastal Navigator will also use the also free (but fewer in
number) S-57 vector charts and raster and vector charts from several
commercial sources.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

Jack Erbes wrote:
wrote:

This is just what I needed. Thanks!

Any thoughts on navigational software for the laptop? Ease of use is
important, cost is secondary.

I use SeaClear II occasionally and it is truly a wonderful donation to
the public domain. SeaClear is best when used with a mouse with a
scroll wheel, otherwise the zooming and panning control are a little
hard to get used to.

If I were going to buy a navigation software today without any regard
for the cost I would purchase Coastal Explorer:

http://rosepointnav.com/CoastalExplorer/Version1_1.htm

I've tried it in the trial version and really found it to be a well
designed product:

http://rosepointnav.com/CoastalExplo...al/default.htm

There are some limitations on the trial version but they are reasonable
enough to let you get a full, although brief, trial of all the features.

Both SeaClear II and Coastal Navigator will use the free NOAA raster
charts. Coastal Navigator will also use the also free (but fewer in
number) S-57 vector charts and raster and vector charts from several
commercial sources.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

Thanks for the info.

Dave