Is This Thinking TOO FAR Out of the BOX

[thataway]

Thank you Jody.

Jay had mentioned Cochise (Steve Dashew"s 78' power boat going up Maskill Harbor in Canada.

Here is the current link to that video. They are using Simrad forward looking Sonar in that case.

The material show that distance of view is: Nominal forward view of 4- 5 times your current depth Maximum forward view of 8 times your current depth. This is not unusual for forward looking sonars.

I am thinking about upgrading the electronics on the Caracal Cat. I am very familiar with the RayMarine (had on C Dory 25). Also Garmin--on the last 22. I have not used Simrad (Navico) since the Tom Cat--over 10 years ago.

I would say in is a "toss up" between Garmin Live view and Raymarine. The Caracal Cat has a bow trolling motor, but I don't keep it mounted all of the time. I probably will go with RayMarine. 3 D RealVision and a 9" screen.

[hardee]

Oh WOW, this is really great. Such good responses, and really exciting to see such good info. Hummmm, maybe more questions now, than answers, but thank you all for the input. Love it.

First, “why do I want real time water speed?” Because then I can tell if I am going “upstream” or “downstream” on the tidal current. Many places in both the San Juan's and north up along the coast in BC, in among the islands, it is hard to tell which way the current is moving unless you stop and watch the shoreline for your drift. Having water speed negates that stopping. It also helps when figuring the ETA for a destination at a given speed. My main use is for knowing what speed to use to maintain a given, static geo location (Boat is not moving relative to the nearby land – used in photography mostly). Can also be useful in calculating water miles versus over the ground (GPS) miles.


“Putting the transducer between the engines may limit the "field of view" and get reflections off the lower units. Not sure if this would be a problem or not.”
From what I have been able to read, the transducer will be behind, and angled slightly ahead of the OB leg, about 3 degrees forward of vertical.


“If you really want a front view display, I would buy one for that purpose and put it on a deployable mounting that you can lower when needed and retract (or remove) before trailering.”
That is a great idea but I do not want that forward facing transducer dragging in the slipstream on a full-time basis. And it is big. (See the photo on Jkidd’s post).
Jody, does the forward scan transducer have aa “kick up” ability?

“This also gives redundancy for Sonar in case one of the systems fail.”
That redundancy is also why I am looking to leave the P-66 on and usable. I like the idea of having a second transduce available."


“What about mounting the transducer in hull under the v-berth.”
This is also a good idea and one I have been considering for a while, especially if it is totally independent of everything else, only showing depth. An inside the hull mount will lose temp, and speed measuring capability. Mounted just forward of the forward cabin bulkhead (helm bulkhead) it would be ideal if near the center. I don’t think that is a crazy idea at all.


“ . . . lift the starboard motor to cut down on turbulence and provide a clear view for the transducer?”
Good idea, and could probably help. Might be the sacrifice in handling I will need to make for increased visibility below.


I am now understanding the “Slice” concept much better. Turning the ducer 90* and moving forward will be a very narrow real picture. Moving the boat across the opening to a tiny bay, may give a better picture, or finding a spot in the bay and doing a 360 rotation might be easier. Doing that with the Axium will allow marking the good anchor spot with a waypoint, and then just go to that. Maybe it will be that easy.

This is really educational. And I am learning.

Thanks for the clinic on transducer vision.

Harvey
SleepyC

[jkidd]

[Karl Konecny]

I also like a paddle wheel on my transducer for a speed signal for all the reasons Hardee mentioned. Out of curiosity, I compared my paddle wheel speed indication with GPS speed-over-ground. On a calm day on a calm lake I went back and forth at various speeds and recorded speed and SOG (I was also measuring fuel flow, rpm, etc. with a couple of propellors at the same time). I found that below hull speed, the paddle wheel indicated low. For example when SOG was 4.8 knots, the paddle wheel indicated 2.1 knots. When I was on plane, the opposite was true: the paddle wheel indicated high. For example when SOG was 18 knots, the paddle wheel indicated 23.6 knots. I still use both keep my custom calibration chart at hand.

[jkidd]

Harvey

They do make NMEA 2000 paddle wheels so if you put a NMEA 2000 network in your boat the new display will read that data. Then you don't need to save the old display.

[ggray]

I have no knowledge of forward or side scaners, but as to the other question, on our previous catamaran, a depth sounder in each bow--about 15 feet apart-- worked fine, same frequency, no interference.

You are, I'm sure, looking for less separation that this.

[hardee]

Karl, On my C-120 there is a speed calibration tool and I calibrated mine down to the lower end of the speed spectrum, from 1 to 10 knots I believe, so it is right on at 5 knots, and The variation is minimal between 3.5 and 7.5 knots.

Jody, Thanks that is a cool picture. Looks very fun. I am under the impression that I can run the output from both transducers to the back of the Axium and then adjust the display to take what ever info I want from which ever device and put that combination of Data up on my screen. (So, I could have the new, HD screen up and still have the
Water Speed off the old ducer.)

Bob, Thanks for that link.

Ggray, with that separation, does it give you good “stereo” viewing?


Harvey
SleepyC