Fish Finder/TotalScan Transducer Help

[OltHunter]

I went out fishing yesterday for the first time in the Sound and ran into issues my my new Lowrance Ti-9 with the TotalScan Transducer.

It appeared to work fine in shallow water, but once we got out into 100+ feet it didn't pick up the bottom and was extremely noisy.  I'm not sure if it is some setting on the unit or could be a faulty transducer.  I figured even if I didn't have the correct kHz/chirp/sensitivity going on, a depth reading would still show up.  I could only play around with it so much before I would start feeling a little sick.

I know all the imaging stuff is meant for shallow water, but i tried lots of different kHz and chirp settings and they all produced the same result, no bottom and lots of noise.  The picture with 15ft depth was heading back into the marina.

I'm not sure if there is a combination of frequency and sensitivity that i'm not figuring out.  I'm hoping so...  I've read somewhere that people run sensitivity down to 4%.  But I would also assume I would get a bottom ping.  I never really played around with that.

So things I've checked out:  updated to the latest version, there are no other tranducers on or any network installed.  Tranducer is installed in the same location as the prior one and level with the bottom of the boat to the top 1/3 of the unit and level with the water.  In the settings, sonar, installation, totalscan is showing.

I have a request in to Lowrance, but that may take a while and I'd like to get back out there soon!

Do any of you have any general info or things to try or your own personal setting recommendations? 

Thanks for taking a look and the help!

PS - On low tide at the Everett launch, avoid the retrieve lanes if you don't have rollers, slicks, or an automatic winch!  They get progressively deeper and you go south on the lanes.

[PolarBear]

Looks like cavitation noise to me (air bubbles interfering with the transducer).  Do you have another unit working at the same time?

[OltHunter]

Looks like cavitation noise to me (air bubbles interfering with the transducer).  Do you have another unit working at the same time?

thanks for the reply, I don't have another unit, and both pictures were taken at 3 mph.  I would have figured the shallow picture would have looked the same if that was the case...but I'm not sure.

[Angry Perch]

Is the frequency adjustable on the transducer. I think 200kHz is for shallow water.

[Stein]

How deep are you loosing bottom?  I usually run medium or high chirp but they only see 300’ in great conditions.

If you want to see bottom in deep salt water, use the 83 hz with the sensitivity backed off a bit and clarity low or medium of the water is full of stuff.

Generally, you can see the fish in great detail or the bottom, not both.  By great detail, I mean picking up loose bait and plankton.  If you are in 90’ you can have both, but not in 500+.

It took me several lazy days just playing around with it to get the hang of it.

Don’t use side or downscan or expect clear pictures like the guys on a lake.  There is a ton of stuff in salt water and you have to get used to interpreting all the stuff you see.

I’ll pull a screenshot from my unit tomorrow if I get a chance.  For coho, I never see bottom or care where it is.  I zoom to the top 125’, usually 40-125 for extra clarity.


Sent from my iPhone using Tapatalk

[OltHunter]

Thanks for the info Stein. I probably just need to play around with it more. I think I did have downscan overlay on, which might have had something to do with it. I've read up a little more and sounds like I should choose fresh water as the default fishing method then play around with the settings. I had it on slow troll.

I think I tried 83 kHz but might not have given it enough time or adjusted the finer settings.

And Angry Perch, it's a 83/200/455 with low medium and high chirp.

[lokidog]

I'm running an HDS unit. I hit bottom with mine set on medium chirp or 83khz and can track bottom to 400+' at 24 mph. I have mine angled about 1/4" low at the back, I think. If it is too straight up and down, I think the transducer can move out of the way of the reflected signal, especially if moving very fast.

On side and downscan, I can tell if mooring anchors are square or round and I even tracked 1/3 of a mile of old electric cable on the bottom about 45' deep. If you know what you are looking at, it is amazing what you can see.

I don't use downscan overlay, seems to just confuse matters.

I don't know all of my settings offhand, but can go over it with you if you feel like calling some time.  360-789-7932

[Crunchy]

Something else is wrong. I fish primarily on 200 and that is in 100-300 fow and never lose bottom.

[Stein]

Thanks for the info Stein. I probably just need to play around with it more. I think I did have downscan overlay on, which might have had something to do with it. I've read up a little more and sounds like I should choose fresh water as the default fishing method then play around with the settings. I had it on slow troll.

I think I tried 83 kHz but might not have given it enough time or adjusted the finer settings.

And Angry Perch, it's a 83/200/455 with low medium and high chirp.

I also punch up the scroll speed and set the ping speed at max.

I scuba dive and can tell you that lakes, Florida and the PNW are very different places.  Out here, 20' of visibility is a great day, there is just a ton of stuff in the water.

This video is pretty good, unfortunately 99% of the ones on YouTube are dudes fishing in 20' of freshwater.

[lokidog]

Good video!

[Stein]

I didn't have the screenshot I wanted, but here is a decent one.  I thought I had one showing the settings, but I was running Medium CHIRP with the sensitivity turned up until the next step up would have made the screen unreadable.  I also messed with the color pallets so the fish showed up dark and well shown. You can see my downrigger ball at 60 with fish in the 40-45' range as well as one at 80'.  The depth reading is wrong, I'm in 600-700' and it is hitting something it is confusing for bottom.

There is a bunch of noise and obvious fish.  My interpretation is that the noise is a combination of scattered herring, tiny shrimp and plankton (stuff herring are chasing).  You won't see the well defined bait balls you do when fishing the bar for chinook.  The bait/plankton/shrimp gets more dense than this, but not well-defined balls.  This or better is what I look for, if the screen suddenly goes blank (all white), I am in someplace devoid of most life and I move.  The more junk, the better from my experience.

On this screen, I was setting a waypoint when I took the picture and was going to circle back on those fish with my rigger at 40'.  I typically run split screen with half the screen sonar and half chart.

The only time I care where bottom is when coho fishing is when I am coming back to port and I don't want to run aground.  For chinook, it's a totally different game as I then shift to looking for bait balls and assuming salmon are nearby.  For coho, I am looking for the actual fish.

I don't know if that's the right answer, but it is what I do.  I will also say that after all this technology, seeing several nets in a certain area is still the best indicator of where the fish are.
That said, I have found some nice spots all by myself where I make multiple passes through the same school of fish.

[Stein]

Something else is wrong. I fish primarily on 200 and that is in 100-300 fow and never lose bottom.

I am almost always at least twice that depth if not more.

[lokidog]

Stein, I thought vertical lines like that were usually electronic noise?

[plugger]

That to me looks like you are not in down scan, Looks like you are using the regular sonar. Down scan is way more precise, it doesn't lie. With a total scan, you should have side and down scan and regular sonar.

[lokidog]

That to me looks like you are not in down scan, Looks like you are using the regular sonar. Down scan is way more precise, it doesn't lie. With a total scan, you should have side and down scan and regular sonar.

That's why I waited until I could find a 12" screen, I run 1/2 screen with the "regular" sonar and then split the other side between gps and either downscan to verify what the other shows or sidescan if i'm trying to figure out the area.