859ci HD "something I found about the transducer"

Maybe some of you that know more about this can explain why. Today while fishing a deep channel I was using a 7' rod so the rod tip was a good ways out from the transducer. As I turned the TM and the back of the transducer was facing the jig I noticed that the jig was picked up better and with less loss of the jig.

I anchored off and turned the TM to the left (jigging on the right side of the TM) and was able to fish the rest of the time with no loss of the jig and was able to pull in a limit from three locations I did this.

http://i29.photobucket.com/albums/c2...pse50d9a29.jpg

Are you saying the back side of the cone shape seemed better than the front side of the cone...??

Good lookin feeshes ...

Rickie

:hesaid

yes the back side of the cone was found to be much better at tracking the jig from top of water column (or i should say just bellow the xducer) to bottom. Normally I would have the xducer facing forward and the jig could be seen either a bright yellow which I take to be the 200 beam or a blackish line of the 83 beam. This would be with me fishing just off to the right side of the TM/xducer and having to stay close to hit the 200 beam.

If I used the back side of the cone (turning the TM to the left and fishing on the right side of TM) I had a bright yellow track mark with no interruption of signal. This was found even if the rod tip was several feet from the back of the TM/xducer. Going back out today so I'll get a few screen shots to show what I'm referring too.

Quote:

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Originally Posted by slabbacks

yes the back side of the cone was found to be much better at tracking the jig from top of water column (or i should say just bellow the xducer) to bottom. Normally I would have the xducer facing forward and the jig could be seen either a bright yellow which I take to be the 200 beam or a blackish line of the 83 beam. This would be with me fishing just off to the right side of the TM/xducer and having to stay close to hit the 200 beam.

If I used the back side of the cone (turning the TM to the left and fishing on the right side of TM) I had a bright yellow track mark with no interruption of signal. This was found even if the rod tip was several feet from the back of the TM/xducer. Going back out today so I'll get a few screen shots to show what I'm referring too.

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Something wierd is in the physics here..

The pulse is strongest in a direct line eminating from the center point of the round disk piezo (inside in the housing)...this is called the sound pulse's "Main Axis"...

The pulse then spreads out as the sound waves carry away from the xducer...

The only way any section of that cone shaped pulse could be "better" ...is if the sound dampening material inside the housing were out of alignment during construction and partially blocking some of the round disk piezo from inside the housing...

I'm confused ...

:scratchhead

Rickie

Quote:

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Originally Posted by rnvinc

Something wierd is in the physics here..

The pulse is strongest in a direct line eminating from the center point of the round disk piezo (inside in the housing)...this is called the sound pulse's "Main Axis"...

The pulse then spreads out as the sound waves carry away from the xducer...

The only way any section of that cone shaped pulse could be "better" ...is if the sound dampening material inside the housing were out of alignment during construction and partially blocking some of the round disk piezo from inside the housing...

I'm confused ...

:scratchhead

Rickie

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Rickie, as you know, I know very little about the physics of Sonar. My question would be, what if the "round dick piezo" was more to the rear of the transducer? Would this make any difference?

:dono:dono:dono

Quote:

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Originally Posted by slabbacks

yes the back side of the cone was found to be much better at tracking the jig from top of water column (or i should say just bellow the xducer) to bottom. Normally I would have the xducer facing forward and the jig could be seen either a bright yellow which I take to be the 200 beam or a blackish line of the 83 beam. This would be with me fishing just off to the right side of the TM/xducer and having to stay close to hit the 200 beam.

If I used the back side of the cone (turning the TM to the left and fishing on the right side of TM) I had a bright yellow track mark with no interruption of signal. This was found even if the rod tip was several feet from the back of the TM/xducer. Going back out today so I'll get a few screen shots to show what I'm referring too.

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Waiting for your findings. I think I will try your method with my Garmin 50s.

Could it be that the transducer isn't on a level plane, and angled more towards the boat ?? Or possibly the piezo is slightly angled towards the rear of the transducer housing (mfg mistake) ??

Could the transducer be mounted "backwards" ??

Could you not reverse the transducer's position & utilize the better reading tendency to your advantage .... ie - being able to see the jig better, while fishing "in front of" the transducer ??

:dono :scratchhead


... cp :kewl

Quote:

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Originally Posted by CrappiePappy

Could it be that the transducer isn't on a level plane, and angled more towards the boat ?? Or possibly the piezo is slightly angled towards the rear of the transducer housing (mfg mistake) ??

Could the transducer be mounted "backwards" ??

Could you not reverse the transducer's position & utilize the better reading tendency to your advantage .... ie - being able to see the jig better, while fishing "in front of" the transducer ??

:dono :scratchhead


... cp :kewl

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You may be on to something here pappy...

If the "Main Axis" were pointing slightly backward under the boat...then dropping the jig thru here would have the jig passing thru the "Main Axis" instead of parallel with it...

Rickie

Here are the shots from today. I had the TM turned to the 9 o'clock position and was fishing on the 3 o'clock side. The first shot is in this position. The second shot was with the TM pointing straight forward, then the third was back the way I had it. In the last shot you can see that a lot of clutter was knocked out.

Attachment 153721

Attachment 153722

Attachment 153723

Was able to get another mess with this technique, to me it's a fun way to fish.
Attachment 153726


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Pappy, I rechecked the xducer and it looks about as flat as I can get it to the TM. At first I thought I bumped it on the mount and moved it but that was not the case. For now I'm pulling in fish and sure as the world if I change something I'll loose a good thing. I think for now I'll leave well enough alone :biggrin

Here was some close calls :banghead

Keep telling myself they were just dinks...makes me feel better :biggrin

Attachment 153731Attachment 153732

WTG...I'm going to give your method a try.. Thanks for posting..

slabbacks,
Which model transducer is this from?

Very nice screen shots!! I am looking at upgrading my 597 DI to an 859 DI at the TM..Thanks for posting this and keep up the good work!

Greg I'm out back at work now so will have to check later. If I'm not mistaking the model is posted on the cable...right?

Treeline

Some of the guys that have got with me about their DI models are having problems. Dont know if its their settings or what.

Yes it posted is on the cable slabbacks. Depending on how old the transducer is it could be printed on the cable or it will be on a label on the cable.

Greg

It's a XNT 9 20 T marked with a yellow tag on the cable.

Thanks, I have been hearing about some sonar problem with the DI models..may wait to see what comes of it..i love those sonar pics keep them coming!

Sb,looks like you had one on and lost him ?

genec

I had that happen several times :biggrin

Had to reel it all the way up each time to reset the knot to the rear of the jig eye to set level again. When a good hook set was made you could see a good steady yellow line come back to the boat. Best video game I ever had :Rofl

slabback,on many hooks,you can bend the eye of the hook back toward the point and it will stay level,don't know what kind of jig you have,weather the eye sticks up any from the lead