Humminbird Side Imaging Forums
Side Imaging Forums => 898c SI => Topic started by: 362 ranger pilot on September 13, 2016, 10:51:04 PM
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I have a 899 ( bow mounted) and a 859 ( console mounted) networked together. Running a XNT 9 SI 180 T on a trolling motor mount and a XNT 9 20 T on my transom.
Both units are up to date on updates. (7.260 on both)
I have my 899 set at 455khz
And 859 set at 200/83 kHz split.
For instance I'm setting in 45 feet of water. 40 feet off the bank in clear water. I can see rocks along the bank with my naked eye, but my units will not show them, just looks like a slick sand bottom? Side imaging was set at 60 feet span. I have both units running off the xnt 9 20 t transducer for down imaging and both run off the xnt 9 si t. For side imaging.
What am I doing wrong?
Do i need to swap places with my transducer and units?
Thanks for any help you can give.
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The SI Range setting is "slant range" not horizontal distance ...
"Slant Range" is a calculation of the Phythagoreum theory in Geometry ...that takes into account the distance straight down (water depth) ...
So your instance of 60' SI Range in 45ft of water is only calculated at a "horizontal distance" of 39.7' ...
(http://i477.photobucket.com/albums/rr134/rnvinc/misc/2C81FD60-49A9-4177-838A-0B8E9CA5B9EB_zpsd4cvedh5.png) (http://s477.photobucket.com/user/rnvinc/media/misc/2C81FD60-49A9-4177-838A-0B8E9CA5B9EB_zpsd4cvedh5.png.html)
Try increasing the SI Range until you see the edge of the water emerge at the edge of the display and then test your scan target rocks again ...
The edge of the display will be black where there is no Sonar return when the SI Range is increased enough to reach the water's edge ...as seen in this point that sticks out at the lower right of this image ...:
(http://i477.photobucket.com/albums/rr134/rnvinc/HB/S00444_zpssstpk8rq.png) (http://s477.photobucket.com/user/rnvinc/media/HB/S00444_zpssstpk8rq.png.html)
Here is more info on "Slant Range vs Horizontal Distance" as pertaining to side imaging Sonar ...
http://forums.sideimagingsoft.com/index.php?topic=946.0 (http://forums.sideimagingsoft.com/index.php?topic=946.0)
Rickie
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If you reduce the distance to the shore then the angle will move more close to horizontal? Say twenty foot down twenty foot out from shore.
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If you reduce the distance to the shore then the angle will move more close to horizontal? Say twenty foot down twenty foot out from shore.
Correct ...
The important thing to remember is that SI range is always shorter than horizontal distance ...
And deeper water affects this difference exponentially ...
Rickie
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Well, that makes sense now. why The units wasn't picking up the rocks the beam has got to get to them before it can see them.lol
I thought the beam was on a horizontal plane.
So for the most part I'm going to loose 1/3 of my horizontal distance? Some times I'm setting in 100 feet of water 50 feet from the bank.
I ran the span down so I would have a better picture (larger). My eyes aren't what they use to be.
I guess I'll run it back up to 100/120 range and leave it there, Till I get a little better with them.
I just got these 2 units and I'm still trying To figure everything out about them.
Thanks for the information!
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>:D
Scan rocks???
;D
(http://i189.photobucket.com/albums/z289/sfw1960/Secret_Squirrel/HB_998cHDSI_v7_51/S00198.png) (http://s189.photobucket.com/user/sfw1960/media/Secret_Squirrel/HB_998cHDSI_v7_51/S00198.png.html)
(http://i189.photobucket.com/albums/z289/sfw1960/Secret_Squirrel/HB_998cHDSI_v7_51/S00210.png) (http://s189.photobucket.com/user/sfw1960/media/Secret_Squirrel/HB_998cHDSI_v7_51/S00210.png.html)
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My images look nothing like yours! I do not get a picture like image😡
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That was done using a Humminbird 998c HDSI with 800 KHz.
You will never get extremely good range with 800 KHz, nor will you get great detail on 455 KHz ~ each is a trade-off.
Some of those boulders are the size of a Volkswagen FWIW.
Practice! 8)
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When using 800khz what are the imitations of 800? Depth? And Range? thanks
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When using 800khz what are the imitations of 800? Depth? And Range? thanks
Yes, both.
The beam angle is smaller on 800 KHz, but definition is greater.
Use 455KHz to located items of interest then use 800KHz to home in on it and get a much better look at it.
The specs for the SI XDCRs are listed on HB's site.
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When using 800khz what are the imitations of 800? Depth? And Range? thanks
Limitations are affected by Enviromental conditions as much as the scientific specs of the equipment ...
A soft mud bottom in shallow water will have the same image effect as a harder bottom in deep water = basically less reflective to bounce the sound pulse back to the xducer ...
A common scenario would be to use 800kHz for trying to see details of targets closer to the boat ...and use the SI Sensitivity to brighten the image (and realize the edges of the SI image maybe darker)...
If the SI Sensitivity can't be raised enough to get enough brightness in the SI image = switch to 455kHz (and realize 455kHz will not be as detailed) ...
Rickie
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The most simple formula to remember is 800 khz less range more power / 455 khz more range less power. Having said that my 898 did much better with 455 khz. The 800 khz seemed too strong, kind like too much flash on a camera. My 997 and Helix 12....not so much. On all I have obtained pretty good images (455 khz) in deep water (160-200') where there was good reflectivity as in the mountain lake in Kentucky I am working in. The other thing besides sensitivity is keeping your chart speed and MPH about the same. My Helix 12 seems to deviate from that as I have to go 1 mph higher than my screen speed. Also disregard the voltage. Not sure why but it always shows low even when connected to a running and charging battery. Mark
[attachimg=1] Helix 12 455 khz
[attachimg=3] 997c SI 455 khz
https://www.facebook.com/Southeast-Louisiana-Underwater-Search-and-Recovery-1438568169746982/ (https://www.facebook.com/Southeast-Louisiana-Underwater-Search-and-Recovery-1438568169746982/)
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Interesting I found the same with the 899, it was way to bright. Had wondered if something was wrong with unit.
I don't recall what the 999 did.
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Interesting I found the same with the 899, it was way to bright. Had wondered if something was wrong with unit.
I don't recall what the 999 did.
The important to remember is that the SI Sensitivity cannot be set at one selection for all imaging ... (regardless of the SI frequency chosen) ...
The sound pulses are attenuated (lessened in strength) by many Enviromental factors also...including water depth, target reflectivity, water particulate, etc ...
The SI Sensitivity should be adjusted frequently to deal with the ever changing Enviromental factors that are being scanned ...
Rickie
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I had turned down the sensitivity quite a bit but don't remember if I had turned it down all the way. I know it was unreadable so I switched back to 455. I do find myself countinuely adjusting settings but that's one nice thing about having the quick menu.
I'll have to try the 800 again in a different place some other time, I haven't tried since that day.
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I'm still having trouble I took the boat out today and messed with the units quit a bit. I swapped the 899 to the console and put the 859 on the bow I figured out I was getting some motor noise off the trolling motor distorting the images more. So I mounted the 899 transducer on the transom. Put the 859 transducer on the trolling motor.
here is the first shot looks like I'm getting a very hard return on the left side with no picture like image this is off my 859. (http://i1106.photobucket.com/albums/h370/Weldworks54/Mobile%20Uploads/6A9610A1-0D96-435B-82FE-B5C0864FE1C6.jpg) (http://s1106.photobucket.com/user/Weldworks54/media/Mobile%20Uploads/6A9610A1-0D96-435B-82FE-B5C0864FE1C6.jpg.html)
Same location with my 899
(http://i1106.photobucket.com/albums/h370/Weldworks54/Mobile%20Uploads/A127A1B3-C047-4719-9C4C-08F4A2EFEE92.jpg) (http://s1106.photobucket.com/user/Weldworks54/media/Mobile%20Uploads/A127A1B3-C047-4719-9C4C-08F4A2EFEE92.jpg.html)
I swapped over to a grey color and this is what I started seeing??? Who knew(http://i1106.photobucket.com/albums/h370/Weldworks54/Mobile%20Uploads/1E357A04-0649-4EEC-BE86-DEDC3A09242E.jpg) (http://s1106.photobucket.com/user/Weldworks54/media/Mobile%20Uploads/1E357A04-0649-4EEC-BE86-DEDC3A09242E.jpg.html)(http://i1106.photobucket.com/albums/h370/Weldworks54/Mobile%20Uploads/16D26628-3B1E-4E5F-87FB-FB4AEBC13627.jpg) (http://s1106.photobucket.com/user/Weldworks54/media/Mobile%20Uploads/16D26628-3B1E-4E5F-87FB-FB4AEBC13627.jpg.html) now my down imagining is all jacked up)
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What little bit of trouble shooting and fooling with the down imaging I got to do is as follows.
I have both units set to read off the 859 transducer. This is the image I'm getting swapping from to either transducer (http://i1106.photobucket.com/albums/h370/Weldworks54/Mobile%20Uploads/15E93B6B-FDB9-4F71-AB0C-F16337C78DCB.jpg) (http://s1106.photobucket.com/user/Weldworks54/media/Mobile%20Uploads/15E93B6B-FDB9-4F71-AB0C-F16337C78DCB.jpg.html)
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Ranger, your speed shows you sitting still. If that is correct that is the issue with your images. You need to be moving 3-5 mph for decent imaging. While moving start with sensitivity at 10 and start at about 30' on your range. If you have 800 khz, don't use it until you tune in your 455 khz. Find a color palette you like and work with that. Try that and see if it makes a difference. Mark
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You definitely have interference .... You will have to isolate the cause by selectively turning things off. I have seen that type interference in the past to be caused by the main motor. The ignition system on some of the new motors seem to be very noisy.
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Sod I was sitting still when I took that picture slight wind blowing me . The down imagining is reading like that sitting still or trolling for some reason? I did notice the depth and temperature on the 899 transducer is not functioning properly. I am beginning to think I have a bad transducer.
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I have a lowrance in dash flasher that was the only other thing powered on besides my livewell pumps when this picture was taken? Could that be causing the interference? Even with the 859 transducer on the TM mount?
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I do see the interference and think you should try a stand alone battery for the unit and see if it (interference) goes away. Then you can figure out what is causing it. When under power from the boat motor do the images clear up except for the interference? And lastly, check the connection with the transducer to make sure you have a solid contact.
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no they do not clear up when I'm at idle
I have a spare battery I've been going to add I will get it added by my next trip.
it's a lot of wire running but I will try anything at this point.
I am currently getting power from the power strip behind the console and the power strip at the bow. Why would the down imaging start doing this after swapping the color pallete?
Someone recommended sticking to a color and working with it till I get it dialed in
I am going to stick with the grey color pallet it Seems to have given me the best image so far.
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The horizontal dashed lines in your imaging are generally crosstalk interference from another unit running at the same time ...
Sometimes troubleshooting is best served by getting the Setup down to the fundamental and work your way up ...
Disconnect all the networking ...
Turn off everything in the boat except 1 unit and its sole connected xducer ...
Test for results ...
Rickie
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I have a lowrance in dash flasher that was the only other thing powered on besides my livewell pumps when this picture was taken? Could that be causing the interference? Even with the 859 transducer on the TM mount?
If it's running 200, 83Khz, or 455 Khz .... it can interfere.
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If it's running 200, 83Khz, or 455 Khz .... it can interfere.
I honestly don't know what kHz it uses transducer is glassed in the hull. It is realitivly close to the 899 transducer maybe 8-12" diagonally through the hull
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The Lowrance is most likely transmitting 200kHz ...which is also what the HB is transmitting ...
Test with the Lowrance off ...
Rickie
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Looking like I'm not going to get to try to work the bugs out this weekend...... work always gets in the way of fun!!!