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SeaJay
26-09-2004, 05:17 PM
OK, we've had some great discussion about interpretation of what you see (or should see) on your sounder, talk about grey-scale vs colour, and of course numbers of pixels.

Now how about something about transducer placement. I, like many, have a standard "skimmer" type transom transducer. With my boat being relatively small and light I seem to have alot of trouble keeping my transducer in good clean water, i.e. water free of bubbles, turbulence etc.

Whenever it is even slightly choppy my sounder (a Lowrance X-48) holds a digital reading of the depth at speed, but I can't get even a half-decent picture on the screen. When things get real choppy, I even have trouble getting a decent image of what's going on at a slow trolling speed.

I'm fairly sure my problem isn't related to electrical interference, but not positive.

What nifty tricks have you all got for transducer mounting. Is it worth looking at a through-hull transducer - I hate the thought of cutting a whole in my baby's bottom!

Cheers
SeaJay

basserman
26-09-2004, 05:26 PM
i know of one trick that works well and all that is is to toe the transducer down (eg angle the transducer at a slight angle downwards)
i need to say that i don't know too many transducers that will work well flat chatters and even if they do what the point by the time you see what on the screen your already 50m past it
but i would be a bit worried about the lost of pic at trolling speed
my old x85 (soon to be repaced with a JRC FF550) i have good picture till about half throttle ;D

SeaJay
26-09-2004, 06:21 PM
Angle the trandsucer down? Hmmm...I was wondering if I should really have it pointing up in the air like that ;)

Actually I have tried angling back and forwards, and a little forwards does seem better. Most of the problem seems to be that there is too much air going past the transducer.
Perhaps extending the mount so the transducer sits deeper might help. The transducer is (?factory) mounted on the small outboard pod on the Sea Jay, so perhaps moving back onto the hull might help. I dunno.

At the moment I get a great picture at full throttle when its glassy calm (and not lumpy), but that's the only time at speed.

Why would I want to have a good picture at speed? Coz i don't drive too and from my fishing spots at trolling speed and am missing out on checking out alot of ground in between my regular spots.

wessel
26-09-2004, 09:47 PM
ww.garmin.com/products/manual.jsp?product=010-00343-00

You will need to place an extra w at the beginning when copy/pasting the link. (A 1.3 Mb download / Need Adobe Acrobat Reader to open the file)

Taken from the Garmin website - Have a look at page 7 and 8 of the manual. There seems to be some mathematics involved in sounder placement - Depending on hull design and prop position.

Maybe this might help in figuring out your problem? If all else fails, why not contact the boat manufacturer, maybe they have had this problem before with another customer???

Good luck

Wessel

Volvo
27-09-2004, 01:42 PM
:)Seajay, i have a skimmer transducer back o my boat and it works perfectly well flat seas or rough and either slow or flat chat..
Mate you may not have it mounted at a part of the back o your tinny that picks up flat water, rather it comes across too many air bubbles??..
Two other little things you can do:)..
Mount it under the floor, close to the keel towards the back observing that , that area does give off flat water..
Being mounted inside its sitting flat and doesnt come across water interference..
Now you can either sickaflex the transducer to the floor of the hull by first applying a good dollop of the stuff to the surface area after having given it a good clean with metho..Slowly push the transducer down moving it sideways back n forth as you do so making sure you are squeezing any trapped air bubbles out and let dry for a good 24 hours before using..They will work through the hull no probs...
Second method is to get a transducer box made up and sickaflex this to the hull of(under floor) the boat. Lid., and a wee groove on the wall of the box(just under where the lid will sit) for the transducer cable to run through after lid has been sickaflexed ..
Oh yes :) a hole drilled in the wall of the box for the transdcucer to be fixed to ie;size of the mounting screw/screws....
(1)Fit Box
(2)fit Transducer inside box
(3)Fill just about to top of box with oil
(4)Sickaflex Lid to box..
PS a wee sickaflex where cable runs through the groove and where mounting screws go through box so no oil weeps through :).
This way there's no muckin around trying to make a mess removing the sixkaflex away from the tranny when you want to remove it...
Gee mate hope ive made sense lol, of the above..Any queries ,drop me an email..
Cheers

straddie
27-09-2004, 03:05 PM
Hi Seajay, I think the size of your boat and mounting position are almost certainly working against you, but before moving the transducer elsewhere use any adjustments you have first.

Try as Basserman suggested and tilt the back down as much as 1 cm. If no good, then use any vertical adjustment to lower the transducer only about 2 or 3 mm at a time, the less the better as the more you drop it down the more you run the risk of it getting wiped out if you hit something.

I can't see the pic of your boat very clearly but it looks like the mounting is right in the very starboard corner of your pod?

If the above doesn't work you will have to move it ::)

SeaJay
27-09-2004, 06:40 PM
Thanks guys,

Here's a pic of the current mounting position, which I believe was chosen by either the factory or distributor. You were right about the position straddie, you must have pretty damn good eyes.

I'm just downloading the info at the link wessel supplied...I'll see what I can make of it.

Volvo you did make sense...scary, but true! I never have been sure that you can shoot through aluminium, so maybe I will give that a go.

Seems I have a few good options there, if the work stops piling-up on my desk I'll get out and try a couple of things and let you know how I go.

Thanks again

aquarius
28-09-2004, 05:13 AM
I reckon you need to mount it under that step........looks like its a bit close to the motor.
This is where my transducer is placed and it works fine at 50 k's.
Might be a different matter on the alloy boat though.
You can only try and see if it gives a better reading.
Maybe try and use some silicon rubber just to mount it......WHEN DRY THAT STUFF IS TUFF AS NAILS BUT YOU CAN STILL REMOVE IT WITHOUT HAVING TO DRILL HOLES IN THE TRANSOME TO TRY OUT THE BEST POSITION BEFORE THE PERMANENT FIXTURE.
Cheers #Brent

Volvo
28-09-2004, 06:44 AM
???Might be the angle i'm looking at it from but seems it coulda been mounted a tad lower??, get a bit more of the transdcucer through the water..
Cheers

Volvo
28-09-2004, 06:49 AM
PS..Seajay is that transducer sitting straight or has it a slight bum down angle to it??..
reason i ask is i had my Sounder play up once and couldnt figure why till i checked the transducer to see it had been tilted off angle somehow??..propably the anchor rope??..Anyhow straightened it up again and "Hunky Dory:)"..
Try anything once prior to making other adjustments ey..
Cheers

Double_Whammy
28-09-2004, 01:55 PM
Hi Seajay
I would agree with Aquarius to the position of the t/d< im no expert with these as im trying to get mine working without any problems (might have got it now ;) ) I just put a foruno into my 5.2 southwind and had troubles for a while as i didnt read manualy properly, it reconmends atleast 30cm radius out from the prop fins. not that ive done that it seams to work fine @ fultilt ;)

CHRIS_aka_GWH
28-09-2004, 02:05 PM
i'd get it off the pod & onto the transom proper. (I think that's what aquarius is saying).

Where it is, already accelerated water would be swirling & expanding around the corner of the pod. My mates who have a similar pod box have theirs mounted on the true transom - not the box & they work well.

chris

Needmorerum
28-09-2004, 05:24 PM
When I first bought my tinnie, the manual for the sounder (X47EX) states that the centre line of the transducer should be in line with the bottom of the hull. Well after trying this, it wouldn't work at high speeds. I approached the shop I bought the boat from, and they said that it needs to be lowered to work at higher speeds, cause I have a flat bottom hull, the water is aerated from the hull. I now have it mounted so that the top of the transducer is level with the bottom of the hull.
The downfall to this is that it then had its own rooster tail that sprayed water on the motor. For this, I made a stainless steel half pipe cover that deflects the spray back down, and also protects the transducer from damage.

Hope this helps
Corry

aquarius
28-09-2004, 05:30 PM
Yes Chris thats exactly what i was trying to say......I'm sure by doing that it will give a much better reading at speed although like the guys have said most transducers lose the bottom when the boat is flat out.
It will also depend on what the water surface conditions are like at the time you give the boat a trial run.
Smooth water will give the best results
Cheers Brent

SeaJay
28-09-2004, 07:07 PM
Thanks guys,

If I can ever get out of this damn office I might mount the transducer on a temporary suction mount and try a couple of different locations.

My impression was that it certainly wouldn't want to be mounted any higher.