Forward scanning sonar

sm sm at videotron.ca
Thu Mar 26 18:27:56 EST 1998


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Mlw2 wrote:


> <snip>
> Anyone had any experience with the Interscope equipment, or others?
>
> Lea Williams
> Krogen 36 "Grace"




Lea,


I take the liberty to repost an answer to Richard, last November...




> Richard Shapiro wrote:
>
> > sm -- (or anyone else who has used the PROBE) - I have been seriously
> > considering buying the Interphase Probe -- up here in the upper Hudson and
> > canals there are few sand bars to run into -- but we make up for that with
> > lots of ROCKS.  The Probe seems to be the ideal solution for trawlers -- at
> > our speeds a forward scanning sonar might actually give enough warning to
> > work!  Please let me know what your experiences are with this gizmo....I'd
> > love to hear from an objective source before shelling out approx. $1,000 in
> > hard earned cash.
>
> Richard-
>
> My experience with the Interphase probe is quite limited. All I can say is that
> for my boat (a Monk 36 Trawler - water draught 4 feet) in the Saint Lawrence
> River it has been helpful. From my experience I disagree with Brian's customer
> comment about the lack of utility in shallow water (maybe Brian should try it
> for himself).
>
> The claim that the device can see four to eight times the water depth is true,
> at least in clear water. When I search for an anchoring spot at near idle speed
> in 6 to 8 feet of water, a visibility of 20 or 30 feet forward does help me,
> since I am mainly looking for a large rock or any other solid artifact that
> could damage the boat. Most of the time, however, the visibility ratio is
> closer to 10:1
>
> I fully agree that one should never rely on only one device. When navigating or
> anchoring in fog, a combination of local knowledge, GPS, sound, radar,
> depthsounder and scanner may all help. When you enter the Saguenay river at
> Tadoussac in dense fog, heavy traffic, no time to lose and whales playing
> around, you can use all the information you can get.
>
> I have not used the Probe in muddy water.
>
> In deep clear water and normal speed (7 knots) I expect the Probe to inform me
> in advance of large objects (whales, containers, coral heads) but this will
> wait for next Summer.
>
> My advice is:
> - if you dont really NEED the thing, wait; probably the quality will improve
> with the next generation
> - if you feel that it may improve your safety, read the excellent article cited
> by Patrick Gerety at www.cruisingworld.com/joedepth.htm (thanks Patrick) and
> pick your choice
>
>                          ||
>                 ____  ||     ~|\                      -> S
>              ~|       ||||||||||||||||\\       __
>                ||||||||||////////////////////////'
>            __ \_______________/
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Diane & Stephen Morgan             M/V Maroli
>
>
>








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<HTML>
Mlw2 wrote:
<BLOCKQUOTE TYPE=CITE><snip>
Anyone had any experience with the Interscope equipment, or others?


Lea Williams
Krogen 36 "Grace"</BLOCKQUOTE>
 
Lea,


I take the liberty to repost an answer to Richard, last November...
 
<BLOCKQUOTE TYPE=CITE>
Richard Shapiro wrote:

> sm -- (or anyone else who has used the PROBE) - I have been seriously
> considering buying the Interphase Probe -- up here in the upper Hudson and
> canals there are few sand bars to run into -- but we make up for that with
> lots of ROCKS.  The Probe seems to be the ideal solution for trawlers -- at
> our speeds a forward scanning sonar might actually give enough warning to
> work!  Please let me know what your experiences are with this gizmo....I'd
> love to hear from an objective source before shelling out approx. $1,000 in
> hard earned cash.

Richard-

My experience with the Interphase probe is quite limited. All I can say is that
for my boat (a Monk 36 Trawler - water draught 4 feet) in the Saint Lawrence
River it has been helpful. From my experience I disagree with Brian's customer
comment about the lack of utility in shallow water (maybe Brian should try it
for himself).

The claim that the device can see four to eight times the water depth is true,
at least in clear water. When I search for an anchoring spot at near idle speed
in 6 to 8 feet of water, a visibility of 20 or 30 feet forward does help me,
since I am mainly looking for a large rock or any other solid artifact that
could damage the boat. Most of the time, however, the visibility ratio is
closer to 10:1

I fully agree that one should never rely on only one device. When navigating or
anchoring in fog, a combination of local knowledge, GPS, sound, radar,
depthsounder and scanner may all help. When you enter the Saguenay river at
Tadoussac in dense fog, heavy traffic, no time to lose and whales playing
around, you can use all the information you can get.

I have not used the Probe in muddy water.

In deep clear water and normal speed (7 knots) I expect the Probe to inform me
in advance of large objects (whales, containers, coral heads) but this will
wait for next Summer.

My advice is:
- if you dont really NEED the thing, wait; probably the quality will improve
with the next generation
- if you feel that it may improve your safety, read the excellent article cited
by Patrick Gerety at www.cruisingworld.com/joedepth.htm (thanks Patrick) and
pick your choice

                         ||
                ____  ||     ~|\                      -> S
             ~|       ||||||||||||||||\\       __
               ||||||||||////////////////////////'
           __ \_______________/
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Diane & Stephen Morgan             M/V Maroli



</BLOCKQUOTE>
 


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