GPS/Depth Instruments

Hello BCCers:

We are continuing the outfitting of BCC #115 and she is
getting closer (ever so slowly) to a launch date. One of the things
I didn’t do when she was being built, was to opt for S. L. Morse
install any instrumentation as I was uncertain about exactly what we
would ultimately or even initially want. (Roger even talked me out
of installing a speed log – when was the last time you
encountered a
company that talked you out of an installation that they might
otherwise have made some $$ putting in?!) Accordingly there
(yet) a single electronic widget on 115 except for a handheld GPS &
VHF. But, as you all know it, is increasingly difficult to keep
things simple in this day of ever proliferating electronic gadgets
that do some really neat things.

In any event we are trying to observe the KISS principle (relatively)
and have decided to have only the “basic” navigation info
to us, i.e.; Where are we? And how deep/shallow is the water (and
maybe… what does the bottom look like?) We have also decided it
would be prudent to have a second GPS aboard since one of them WILL
break sometime (yes we do celestial but on a dark stormy night…
you know how that goes).

What we are (tentatively) looking at is installing a GPS Chartplotter
in the nav area, depth instrument (with in-hull transducer –
also talked me out [at least so far] of cutting more holes in the
bottom of the boat) with some sort of multi-function instrument in
the cockpit (on the stbd cabin ext bulkhead) which can repeat/read
nav & depth info coming out of the depth instrument & GPS either
through Raytheon’s SeaTalk system or standard NMEA output msgs.
it is already getting complicated!

Specific equipment under consideration is Ratheon’s Raychart 420
their new 320), ST40 depth instrument and their ST60 multifunction
repeater for the cockpit. One of the conundrums we are facing is
that if one is going to shell out X$ for a depth instrument why not
add some more $$ and get a dual freq fishfinder so you can get not
only depth but bottom contour info as well (plus perhaps aiding in
finding a fish dinner). Which then leads to the question: If one is
going to install a GPS chartplotter and a fishfinder why not go to a
combo unit, e.g., Furuno or Garmin for example? Thus saving space in
a relatively small nav area.

On the other hand, we could just opt for a handheld chartplotter
which would be easy to move into the cockpit when needed forget the
fishfinder and just install a depth intrument…

It’s never simple is it? So, my fellow BBCers, I would

  1. Any thoughts/experiences/recommendations you may want to share
    with regard to our “approach” as detailed above plus info on
    equipments you may be using on your BCC’s (for position/depth
    and technical/maintenance difficulties associated therewith.

  2. Anyone using in-hull (shoot-thru) depth transducers. If so,
    anyone having problems with depth range/signal quality?

Thanks in advance,

Pete Cisek

At 08:47 PM 09/17/2000 -0000, you wrote:

Hello Pete:

For what it’s worth, my current plans are to use a Garmin 175 chart
plotter w/remote antenna so I can have it either at the nav
station…probably not often…or in the cockpit…where the helmsperson
usually needs it. Will also have a less elegant GPS as backup…then
charts…celestial…etc etc. Might put a slightly bigger chartplotter
at the nav station later on…as my eyes get older. I am currently
using just the 175 in the cockpit and it works swell here on the Great Lakes.

Will have an ST40 depth instrument in the cockpit…have yet to find
anyone’s repeater that will show me Lat and Lon…so have given up on
the repeater solution…who cares about speed etc. unless you are racing?
With the GPS, I will know SOG anyway. I agree with Roger on limiting the
number of holes in the hull through which the sea can come!! The only
limit on a properly installed in-hull transducer that I am aware of, is
some loss of deep readings…but do you really care if you are sinking
in 700 or 1000 feet of water??

Best regards,

Tom Harrer


FWIW, we’re planning to use the base level Nexus system with depth
and speed. We like to tweak sails, so speed through the water is
part of the fun factor, and we’ll just have to deal with cleaning
impellers, etc. Also, I’m not prepared to spring for a Walker log to
back up the GPS for distance information, so a knot meter it is.
Nexus has a 2 year warranty, and got a good review from PS. Also,
you can plug the GPS into it and have nav info in the cockpit.
Finally, I think that the depth and speed, though integrated, can
operate independently, so if one tanks, the other can continue. Now
if the server tanks, it’s back to the leadline!

Where have you landed? Drop me an e-mail when you get a chance!

Tom Unruh