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thylacene
31-05-2011, 10:52 PM
OK, have experimented much and struggled to get consistent results.

I find that when it is a bit rougher, the depth indicator on the display just flashes and it is not until we stop that it gets bottom. On a really nice day we get readings up to around 21 knots, other days less

Up to what travelling speed should I expect to maintain a depth reading?

At what depth should I lose bottom?

Seems to run out of puff around 190m but we get fish symbols at 300 - 350M when out on the shelf

Transducer is a 600W 200/50 hanging off a Garmin 750S

What do others experience?

Thanks

Thy

Feral
01-06-2011, 04:05 AM
Your transducer might be ending up clear of the water on full song in the rougher water.

Lancair
02-06-2011, 07:53 AM
Thylacene, you are getting much better results than I am with the same setup. I dont loose depth reading at any depth so far (up to 110m anyway) but I loose bottom picture completely in over 50m !! Ive tried different settings from full Auto to everything else on or off and everywhere in between. Fishing close inshore reefs the sounder is brilliant, so much better than my previous garmin.
Another thing that annoys the crap out of me is if I get into 0.4m or less the depth display starts flashing and will not stop on entering deeper water again. It keeps flashing 0.4M. Ive tried all sorts of settings to no avail, the only thing to do is turn the whole thing off and on again. What the ????

Lancair

trueblue
02-06-2011, 07:59 AM
some hulls just give grief setting up transducers, as there is too much hull interference no matter where you put it as there is no sweet spot.

trueblue
02-06-2011, 08:01 AM
I like the idea I have seen recently with some setups of the big 1kw transducers sitting directly in front of the motor (centre of keel) Lots of literature I have reads says not to do that, but for some boats and some transducers it seems to be working a treat

something to be investigated for me

Smithy
02-06-2011, 09:00 AM
Losing power at 190m doesn't sound like a true 600w unit. I my experience 300w units run out of puff at 170-180m, 600w units around 240-280m and 1kw around 500-700m.

business class
02-06-2011, 09:06 AM
it takes alot of time to set up a transducer. i have a 1 KW transducer and i can pick up bottom at all speeds and all conditions (that ive been in so far and i have been in some crap) i dont loose bottom till 650m. Its a heart ache in setting it up but its well worth it.

Vitamin Sea
02-06-2011, 10:39 AM
Hi Smithy

I was reading 186 metres on 200khz with my 600L (think they are 350W), I'm waiting to see what I can get out of the 585 with the 600W ducer before I look at a 1 ikw, any idea? i'm thinking it will have to be good for 400M?

Cheers

Bill

Smithy
02-06-2011, 10:06 PM
Bill,

I doubt if you will get into the 300s with a 600watter. The ambient conditions (amount of current, amount of life in the water, density of the water, etc., etc.) all have a bearing on what you can read. The 600L we had on the shelf all the time ran out of puff in that 170-180m area every time.

oldboot
02-06-2011, 10:46 PM
Remember the power rating of you transducer be completly irrelivent if you sounder does not have the power output to drive it.

1000 watt transducer......200 watt sounder..........200 watt output....increasing the rated power output of your transducer will give not a spot of extra power.

cheers

johncar
06-06-2011, 09:28 AM
I must have been lucky with this one. My Garmin 5012 + sounder module with just a standard 600W transom mount seems to read clearly and uninterrupted at any depth ( But I only have fished at up to 110 metres out off Moreton to date) any speed or conditions doesn't seem to worry it. The first sounder that I have ever been happy to just run on auto and use an outboard duser.
The only change I make to make other than auto is to Zoom down in the deeper water and must remember to zoom back out when back in the shallows or it will lose the bottom. Take the zoom off and all good again.
I think my unit will power up to 2KW so I know I should be getting the benefit of the full 600W compared to a unit that may have a 600W transducer but only be able to supply 300W to it.

In the past I have usually resorted to a 1KW through hull setup but happy not to have to do it in this case.
If I go deeper and run out of puff I can worry about a bigger ducer then.

I seem to recall that when running my unit in the manual mode and setting the depth range manually, you need to keep bringing it down to minimum range when you get into shallow conditions as it will also lose the bottom and just sit there flashing at you.

whiteman
06-06-2011, 02:23 PM
I have recently punted my Furuno 620 and replaced it (and the old plotter) with the Garmin 750s. I had to get rid of the Furuno as I could not get a depth reading over 10 knots and as for seeing the bottom when moving, hopeless. I have an extensive thread on this in the Electronics section. I am not critical of the Furuno as it is far and away the best sounder picture I have used, far better than Garmin, but on my Quinnie the tranny would not co-operate for me.

So am now in the process of tuning the Garmin with a 500w transducer (mine is standard - is yours an after market 600w?). On Sunday in very rough conditions in depth up to 25m it kept the depth reading solid over 20 knots which is fantastic but the bottom started getting fuzzy over 10 knots. In smooth water inshore (up to 10m) the bottom picture was OK at 20 knots but not spectacular. I have yet to try any adjustments so this may improve but it is still very workable for me. I have the tranny sitting around 10mm lower than the manual says and around 2 degrees forward tilt. My next trick is to tilt it more level.

I hope you don't go through my pain of the last 12 months.

whiteman
06-06-2011, 02:29 PM
Thylacene, you are getting much better results than I am with the same setup. I dont loose depth reading at any depth so far (up to 110m anyway) but I loose bottom picture completely in over 50m !! Ive tried different settings from full Auto to everything else on or off and everywhere in between. Fishing close inshore reefs the sounder is brilliant, so much better than my previous garmin.
Another thing that annoys the crap out of me is if I get into 0.4m or less the depth display starts flashing and will not stop on entering deeper water again. It keeps flashing 0.4M. Ive tried all sorts of settings to no avail, the only thing to do is turn the whole thing off and on again. What the ????

Lancair
I noticed in 0.8m mine started flashing and then I hit sand. I thought these things were supposed to measure to 0.3? Off the sandbank and the reading came back once I got into 1m. You may have something wrong with yours but I have yet to plow through the manual even though it seems to be 50% about setting up the radar!

johncar
06-06-2011, 06:09 PM
So am now in the process of tuning the Garmin with a 500w transducer (mine is standard - is yours an after market 600w?). .

I am not sure but I seem to recall that the 750S comes standard with a "Garmin supplied" 500W transducer. My model comes with nothing and had to buy everything separate, being the GSD22 module and tranny. The dealer told me that they would fit an Airmar 600Watt but as a result of this thread I just checked the Transducer which has no brand on it other than the US patent:
http://www.freepatentsonline.com/6377516.pdf

Which appears to be the Garmin standard 500Watt. So there you go, looks like I got mislead once again which doesn't surprise me.
Anyhow the 500Watt standard Garmin tranny seems to work fine for my purposes so far and as I said very stable at any speed, so all good at the end of the day.

FishHunter
06-06-2011, 07:11 PM
Strange. I fitted my Lowrance Elite as per the directions and so far I have clear bottom at 70km/h in 20m and clear bottom at 45km/h in 45m smooth or rough. It doesnt get much deeper than that around here so cant test it in deeper water

Relaxedcamper
07-06-2011, 09:57 AM
Hi, I have been reading through this thread and would like to ask for some advice. :-?

We have a Lowrance LMS520 sounder installed on the back of a Haines Signature 500c. Our problem is that at any speed over about 10-15 Km hr the bottom completely drops out and we have no depth measurement. The previous owner said that it always worked even at WOT.

Can you guys have a look at the photos and see if it is in the right orientation.

Many thanks.

http://i954.photobucket.com/albums/ae28/relaxedcamper/Haines%20Signature/IMG_6039.jpg

http://i954.photobucket.com/albums/ae28/relaxedcamper/Haines%20Signature/IMG_6038.jpg

johncar
07-06-2011, 10:30 PM
It looks OK in the pics but hard to determine the longatudinal angle. You need to be sure it's in clean flowing water not behind any strakes or things.

You also need to be sure that the back edge is angled slightly down a couple of degrees lower than the leading front edge.
If it is running flat or slightly up at the back you will often get cavitation under it and air bubbles and lose the signal.

Relaxedcamper
08-06-2011, 08:33 AM
Thanks Johncar. The transducer is sitting level so I'll adjust it a little so the back is pitched a little down. The see if that will make any difference.

Thanks for the advice.

Cheers.

deckie
08-06-2011, 05:29 PM
Bizzarree...sometimes makes u wonder just how far tech has come...and how the prices are justified.
Recently gave a >20yo b/w 5 inch with original trannie to a mate, and he is also holding bottom with it on his tinnie at 50kph. That little thing gave me a reasonable signal at 130m and it was off the rack...and the actual depth never cut out, and in <1m it'd never act up.

whiteman
09-06-2011, 12:29 PM
Yep, my old Lowrance 135 never missed a beat. I think the problems come from the new style of digital trannie which seem to be much better at reading the bottom in still water but don't like air bubbles.

buck66
10-06-2011, 10:10 AM
Furuno FCV620 and Airmar P79 holds bottom at 45knts got to love that.

Smithy
10-06-2011, 09:43 PM
Relaxed Camper, angling that trannie down a bit should help you heaps.

Relaxedcamper
11-06-2011, 09:14 AM
Hi Smithy, Thanks. How much do you think.? The manual says a few degrees. I have done this yesterday but you can not really notice the angle difference. Rather than talking about angles, could you suggest how much lower the back should be in relation to the front. IE 10-15mm etc.

Cheers.

whiteman
17-06-2011, 01:04 PM
Hi Smithy, Thanks. How much do you think.? The manual says a few degrees. I have done this yesterday but you can not really notice the angle difference. Rather than talking about angles, could you suggest how much lower the back should be in relation to the front. IE 10-15mm etc.

Cheers.
If you have a level bar place this on the hull and adjust the mid line of the transducer from this a couple of millimeters. Or use that incredibly handy iPhone app "iHandy level". It shouldn't need much. The next step would be to move the transducer 1cm deeper and see what happens.

Smithy
17-06-2011, 04:33 PM
I'd go 10mm or so. Shouldn't be a problem. Just remember it is going to make your fish arches from perfect arches into Nike ticks as the transducer face is not going to be flat with the ocean floor. Bit of a trade off for reading at speed.

All of this is transducer placement. My Furuno with the 1kw transom mount on the Stabi would hang in perfect at 34knots and the standard P66 triducer of the JRC on the 702 Signature would hang in at 38knots perfectly. Now I have taken the 1kw Airmar off the Stabi and put it on the Capricorn it is reading terribly. I know it is not in the ideal spot but I had an existing slide bracket there I could make use of. Next time the boat comes out of the water on the travel lift it will be going on the starboard side for sure.