Ghost lines on sideview?

[Larry3215]

I thought the reason these ghost lines (dark bands just inside the bottom return) show up on sideview was from having the downview on the same frequency as sideview, but Im getting them when they are on different frequencies - but only when the sideview is set to 455. They dont seem to show up when sideview is set to 260 even if downview is also set to 260.

Do I have that wrong or is something else going on?

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[Larry3215]

Here are a few more all at 45503MAY16_1458_01.jpg03MAY16_1457_00.jpg

[TroyBoy30]

use a different frequency on sidevu and downvu

[Larry3215]

LOL

You didnt look at the pictures Troy! Thats what I have been doing and I still have the ghost lines. In this shot Im running down on 260 and side on 455.

[Larry3215]

And in these three shots, downview was always on 260 and I switched between 260 and 455 on sideview. I got the ghst lines when sideview was on 455 and down was still on 260 but (almost) NO lines when they were both on 260.

Thats exactly the opposite of how I thought it should be.

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[TroyBoy30]

sorry i only looked at 1. mine go away with diff freq

[Larry3215]

Yeah, mine get worse when on different frequencies.

This was making me wonder of they had the frequencies wrong on sideview or downview. Its always been odd to me that 260 seems to make better side images than 455 on sideview.....

[Larry3215]

Hmmm. I wonder if Im getting interference from my PS21? The frequencies are close when Im on 455 in CHIRP mode....

Anyone else have any sideview shots taken at 455 with or without a PS21 running?

[TroyBoy30]

maybe? heres the normal results of changing the di freq

Could you please advice why waffle effect had disappeared on the second screen shot. The same depth, the same speed….what is the difference in settings? Did you turn off Dv or just used different frequencies for Dv and Sv?

No problem. I changed DV to 800khz.

[Larry3215]

Yeah, thats exactly how I would expect it to work Troy.

Im going to have to do some testing next time Im out I guess - unless someone with a PS21 has some more sideview screen shots to share on 455 khz.

[cactusflyr]

Seem to recall somebody referencing three beams on the higher frequency causing this phenomenon. Going out today....have the same issue...doesn't bother me though.

[Larry3215]

If you get a chance, do a quick test and let me know if turning Panoptix on/off changes the lines when you are on 455.

[cactusflyr]

Mine is 455 and 800. Same thing....doesn't really affect anything. 455 on top, 800 on bottom.

Won't seem to post.

[Larry3215]

Can you email them to me? I will PM you my email address.

Also, what transducer are you using? GT52 or?

[cactusflyr]

Done...yes gt52. 455 on top, 800 on bottom

[Larry3215]

Got it!

Is that lower pic with PS21 ON? What happened when you turned the PS21 off? Did you happen to notice what frequency your downview was set to?

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