Flasher as panoptix alternative?

[Schins]

ya just pondering a little here, but has anyone ever tried mounting an ice ducer on a trolling motor hooked to a flasher?

In theory it seems it might be a cheap-mans panoptix although i could see a problem with not having a bottom return properly.

[puhlw]

Cone beam is real small on most flashers so you can't see very much.

[MonteSS]

Most depth finders have a flasher built in. Not sure how you are trying to compare that to Panoptix?

[Larry3215]

I tried that several years ago with a Humminbird and a Sitex. Didnt work worth a darn.

The Panoptix "beam" is very different from regular sonar, so you wont get close to the same effects.

[Schins]

Ok. I just wondered, as a fish finding tool only, if it was viable.

Monte.....real time sonar

[Larry3215]

Cone beam is real small on most flashers so you can't see very much.

Actually a vert small cone angle will help a lot. My problem was having too wide a cone angle. It got returns from the surface and the bottom at the same time and pretty much wiped out any fish returns or made them impossible to see.

[Schins]

do you remember what those angles were? and did you experiment with pointing the transducer?

[Larry3215]

The Sitex was a simple 50/200 I think, but Im not sure. Its been way too long. The Humminbird started off with the Compact SI transducer then I got the HD version, so what ever those cone angles were.

My tests involved mounting the transducers on a stick so it could be tilted up and down to point at different angles other than straight down and allowed me to turn it in any direction.

In really deep water it sort of almost worked for seeing targets suspended mid water column, if you didnt tilt it too far, but it wasnt very good at all.

[Wayne P.]

The Sitex was a simple 50/200 I think, but Im not sure. Its been way too long. The Humminbird started off with the Compact SI transducer then I got the HD version, so what ever those cone angles were.

My tests involved mounting the transducers on a stick so it could be tilted up and down to point at different angles other than straight down and allowed me to turn it in any direction.

In really deep water it sort of almost worked for seeing targets suspended mid water column, if you didnt tilt it too far, but it wasnt very good at all.

Both the Humminbird Compact SI and HDSI transducers have the same 2D crystal---83/200 kHz with spec 60/20 degree coverage at -10db.

[Schins]

Revisiting because Randall53 started a thread on shooting under docks.

I was thinking of something like a Marcum or Vexilar flasher which use narrow 8 or 9 degree cones. I wonder if it might actually work if the cone was kept up off bottom as much as possible?

Even though its a different type of sonar than Panoptix, it's still real time.

I need to find a really good deal on a narrow-cone flasher and try this for myself

[DonnieG]

Is Panoptix kind of a "rapid fire" 2D?

[Larry3215]

Someone in the other thread mentioned using DI to look under docks. You have a much better chance with a 1 or 2 deg cone than with even an 8 deg cone. As soon as the beam starts getting returns from the surface or bottom or underside of a dock, the fish returns will be lost/hidden in those returns. The problem with the DI cone is its so wide the other way. You will have a hard time telling where the fish is in that direction.

Panoptix is not like rapid fire 2D. The Panoptix beam shape is closer to DI than 2D in that its wider one direction that the other, but the widths are different. The skinny direction is wider and the wide direction is narrower for the Forward looking models and wider for the down looking models.

The big difference though, is that the beam is electronically steered or swept back and forth through the wide portion of the beam. Imagine a DI cone that swept back and forth from the bow to behind the stern constantly and updated the entire screen at once, in real time, instead of scrolling.

Panoptix is s a very different animal.

[Larry3215]

Revisiting because Randall53 started a thread on shooting under docks.

I was thinking of something like a Marcum or Vexilar flasher which use narrow 8 or 9 degree cones. I wonder if it might actually work if the cone was kept up off bottom as much as possible?

Even though its a different type of sonar than Panoptix, it's still real time.

I need to find a really good deal on a narrow-cone flasher and try this for myself

This might work, but the key will be keeping bottom returns and surface returns off the screen. Also, you wont be seeing arches unless your turning the transducer side to side, or cruising past the dock, so keep that in mind.

Also, remember that sonar cones are not nice sharp, linear things. They have bulges and curves and are different widths at different distances from the transducer. I have no idea what the actualy cones for a vexilar are but they could well be something like these images, so the actual cone width may be much wider than the spec closer to the transducer.







Sonar Cone332.jpgcone coverage 03.jpgSonar Cone22.jpg

[Schins]

In your second pic especially, at what fow would those wide side lobes be at typically?

I have a hard time seeing my jig on any of my brands and kHz selections in under 15 fow

[Larry3215]

As far as I know, no manufacturer provides that information. Probably because it will vary tremendously depending on the Power/Sensitivity/Brightness settings in the mfd. The effective "cone width" gets wider or narrower as you change Power/Sensitivity settings up or down.

You can kind of gauge that for yourself by looking at the thickness of the "bottom" in a 2D or downvu image. The thickness of that bottom return is a gauge of how wide a section of bottom the transducer is "seeing" returns from. So, the thicker the "bottom" is, the wider your effective cone angle is - at that distance from the transducer.

Here are a couple of screen shots and a crude drawing to illustrate this. These show how it works when you have a transducer with a wide cone at 77 khz and a narrow cone at 200 khz, but it works the same way when you change power/sensitivity/brightness. Look at the thickness of the red portions of the bottom. The red is the strongest returns. It is much thicker on the 50 khz side - which has a much wider cone.





Quinty (6).jpgflat dead.jpg

[Schins]

We need LWinchester on this with his 10deg Edge

[csurp]

It also seems probable, because of manufacturing quality control, individual transducers of the same spec can vary within and between batches. I was once told that is the reason you can pay $50 or $5000 for a transducer.

[Treeguyus]

Years like 30 or more ago I took a trolling motor transducer and placed a screw on the back edge of the transducer raising the back a little more then 1/8th inch. Worked well for scanning drop offs the wide return meant a long sloping taper, short return meant flat. Revolving the head really helped see this.

A thought I had

[Schins]

Nice

[Larry3215]

Years like 30 or more ago I took a trolling motor transducer and placed a screw on the back edge of the transducer raising the back a little more then 1/8th inch. Worked well for scanning drop offs the wide return meant a long sloping taper, short return meant flat. Revolving the head really helped see this.

A thought I had

Good point! Yes, sloped bottoms also increase the thickness of the bottom return.

How thick the bottom layer on the screen is depends on all these things acting together...

Cone width of the TD - wider = thicker
Power/Gain/Sensitivity/Brightness = more of any = thicker
how hard or soft the bottom is - harder = thicker
Bottom slope - more slope = thicker