Depth readings / sonar charts

JTulls

.
Dec 6, 2014
89
International 14 and J-Boat J80 San Diego
I know depth sounders are important to have on a keel boat...but does anyone use sonar or a live feed of the depth? If you do have sonar what do you use it for besides finding fish? I was thinking it be useful for scouting the bottom for good anchoring locations...anything else?

The Navionics app can connect to a Vexilar T-Box unit over a wifi signal and give you live sonar readings. It looks really cool and I want to try it out! https://www.youtube.com/watch?v=usUHeqoasvk&feature=youtu.be&list=UUfsH8_ZBtDhrT0j3mpDRwog
 
Oct 22, 2014
352
Pearson P303 #221 RockPort Maine
I will just say.. That's why it states.. " I Agree" before you run the APP... LMAO. Ronald Reagan said it best.. "Trust, but Verify!". Enough said. Capt. Rob
 
Sep 29, 2008
1,976
Catalina 310 #185 Quantico
It is nice, but ...

They need to have a hockey puck model you can attach to your keel instead of your transom, or even better, make it compatible with the existing transducer. I would actually prefer to replace my Raymarine ST-60 depth readout with a real fishfinder like display that fits in the same space.

All this cute WiFi stuff is a step in the right direction, but do you want to trust to WiFi and a tablet in a storm when you really need it?
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
The cat's meow is forward looking sonar. Looks out to about 5 boat lengths, plenty of time to change course when moving at gunkholing (aka running aground) speed. Does take some getting used to as the beam forward is pretty narrow. If you imagine sweeping a flashlight and only being able to see that is directly in the light. Sweeping the beam is done with the boat direction and going around curves is an exercise in mental imaging.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
I know depth sounders are important to have on a keel boat... If you do have sonar what do you use it for besides finding fish? I was thinking it be useful for scouting the bottom for good anchoring locations...anything else?

dont confuse the sonar we use as depth sounders and fish finders in our sport boats with the sonar used by submarines, warships and explorers like dr. robert ballard... that stuff is way advanced over our simple devices.

We dont need to find fish so much as we need to know how deep the water is in which we are traveling thru... its a basic necessity of boaters everywhere since the beginning of time, except for those that can actually see the bottom...

There are many reasons to need to know your depth, most importantly so you can keep your boat afloat. Others are, Searcing for a proper depth for anchoring, searching for the hidden reef so you either dont hit it or so you can hook it with an anchor and scuba dive it.... or making sure we arent getting into water too shallow to travel in..... using the readings to compare against the chart for navigating and charting your position... many other eeasons you may want to know, but the simple devices we use wont find us an enemy to shoot at, or a treasure chest full of pieces of eight... but having one and knowing how to use it may save your boat or your life, or maybe just an expensive embaressment from having to be pulled off a sandbar by a tow company...
 

JTulls

.
Dec 6, 2014
89
International 14 and J-Boat J80 San Diego
I've been doing some more reading on this setup and it looks like in addition to the live feed of the bottom, you can update the SonarCharts layer on the maps to get real time depths of the water that you're sailing in. Check out this demo video: https://www.youtube.com/watch?v=ktnCWJA1wyU
 
Mar 13, 2015
1
ONTARIO 32 Penetanguishene
YES we used the Interphase System on a vessel we were delivering east to west on Lake Erie a few years back. Drove us a little nutty on the night watch as it kept alarming us of objects ahead in the beam. Turned out to be schools of fish, alewives smelt or shiners that we finally got a light on. System was new tool to us and we did not set up any filters for soft targets.
 
Sep 29, 2008
1,976
Catalina 310 #185 Quantico
More thoughts

The comments here are interesting. I should note I am a retired Submarine Sonar Technician and I worked at the Naval Sea Systems command for a few years designing Sonar systems. I agree with Centerline that we should not get confused as to the difference between a depth sounder and a fish finder as the difference is between basic information and much more advanced information. On out 2nd sailboat we had a Humminbird SX-100 fish finder with the transduced epoxied to the inside of the hull just forward of the keel. It was exceptionally useful as you could see the contours of the bottom as well as getting a good idea of the bottom composition and what was directly below you. The current generation fish finder are pretty sweet, and I do like the idea of the new Navionics Sonar charts where they key feature is the community input on updating soundings. Crowd sourcing of depth soundings and other features is long overdue. Active Captain also has some tie ins (I believe Lowrance or Furuno) to integrate community input into their chart plotters.

As with my earlier post, most of the time I just want something simple and in a format that will fit into my existing set up as I do not need or want yet another piece of gear cluttering up my cockpit. Considering that Humminbird unit was only about $100 and black and white it was far superior to my current ST60 unit that only gives me depth.
 

Attachments

Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
The comments here are interesting. I should note I am a retired Submarine Sonar Technician and I worked at the Naval Sea Systems command for a few years designing Sonar systems. I agree with Centerline that we should not get confused as to the difference between a depth sounder and a fish finder as the difference is between basic information and much more advanced information. On out 2nd sailboat we had a Humminbird SX-100 fish finder with the transduced epoxied to the inside of the hull just forward of the keel. It was exceptionally useful as you could see the contours of the bottom as well as getting a good idea of the bottom composition and what was directly below you. The current generation fish finder are pretty sweet, and I do like the idea of the new Navionics Sonar charts where they key feature is the community input on updating soundings. Crowd sourcing of depth soundings and other features is long overdue. Active Captain also has some tie ins (I believe Lowrance or Furuno) to integrate community input into their chart plotters.

As with my earlier post, most of the time I just want something simple and in a format that will fit into my existing set up as I do not need or want yet another piece of gear cluttering up my cockpit. Considering that Humminbird unit was only about $100 and black and white it was far superior to my current ST60 unit that only gives me depth.
if someone actually has the time to learn and use all the features of all the basic electronic gear that we use on our simple boats, then they surely arent taking their R&R seriously.... I dont come to the boat to study the manuals, so I want a simple depth sounder I can turn on and let it do its thing... the same with the VHF, the GPS, and the RADAR.... yep, I do like to know where i am, where im going and who is around me in the fog or at night, but I only have to turn the switch on to get the information....

my point is, the new equipment with all its built in gadgetry, bells and whistles is overkill and only causes stress levels to rise when we try to figure it all out, but we do still need manuals to help us figure out even our most basic bell-less and whistle-less equipment sometimes... keeping it all to a basic minimum is a much better way for the sailor that wants to relax and enjoy life:D
 
Last edited:
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
You clearly don't do much gunk holing Centerline or you are comfortable with running aground alot. (not a criticism BTW). I have found the standard depth finder to be more than adequate for just about everything except finding that low spot over the entrance bar to the creek. On the Chesapeake this is an almost every outing sort of thing.
 
Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
You clearly don't do much gunk holing Centerline or you are comfortable with running aground alot. (not a criticism BTW). I have found the standard depth finder to be more than adequate for just about everything except finding that low spot over the entrance bar to the creek. On the Chesapeake this is an almost every outing sort of thing.
quite to the contrary... its my boat you will see up in the cove the farthest, or in places where others are afraid to go... Im NOT afraid to "test the waters" and im not comfortable being aground either.

a simple depth sounder and common sense is all I have ever used or needed on any of my boats and until I get rich and have more time and money take my boat equipment and gadgets more serious, its all i will ever use..

in 45 years of boating, I have only been hard aground 3 times (as opposed to hitting hard ground)... once at high speed in a powerboat, and run aground on a shifting sand bar on the columbia... and twice in my Mac25.... but in the 25 i only had to unlock the keel and crank it up....

I have discovered on my 34, that the design and balance of the boat with the long length of the "fin" keel, as soon as the forend of the keel touches something firm enough to hinder/slow my forward progress, it will cause the bow to dip enough to let the keel dig deeper stopping the boat.
once the boat has stopped, the bow rises and I am floating again... so providing i dont have a following current, I can back away.... this probably wont work as slick on a hidden rockpile:cry:

BUT, this ISNT how I normally navigate:D:D, but only an observation that i made when trying to get into my marina when approaching from the wrong angle.

and I can see the advantage of forward looking sonar, and in some areas it would be more useful than others....

we once hit a rock/reef with the keel of our 25 while sailing in in the middle of a lake in central oregon... we bounced over it, but it was definitely an event that i dont want to happen again.
there are no charts available for the lake, and it is not a common sailboating lake as the winds are to shifty, so it was unmarked... but thats ok, cuz I was able to find it without a marker;)
forward looking sonar could have saved me from that momentary excitement.