Electronics in angling

[olsmelly]

I was reading an advert in an angling mag the other day, concerning a complicated electronic lure, which creates an electric charge, in use.

I have to say that I thought it OTT.

HOWEVER!

All lil tiddlers (and big 'uns) generate minute electric fields, when moving, so why not OUR lures!

But not at high prices............

The electric charge does not need to be very much. So why not create yer own micro-generator and booby bead?

I reckon a visit to Maplin will produce mini cylindrical magnets (1mm dia.) and enough 0.1mm lacquered wire, to do the job, for, say, a dozen, for under £10! (I did some checking).

I'm thinking of 3mm polystyrene tube and 3mm polystyrene rod. (just like my "drummers". I make my own boobies). I'll need some 2mm poly rod, as a former as well.

Now I need to wind 100 turns on to the former (10mm total length) fix with superglue and repeat, say, 5 times; s/gluing each additional winding. IMPORTANT! HAVE THE WINDINGS TURNING THE SAME WAY!

Now, using a good dob of Araldite, fix the windings(sans former) inside the 3mm tube. Allow for a length of "tail", to run out of the sealed tube (say 5cm).

Seal the "tail" end with a 2mm plug of the 3mm rod, allowing a groove to accept the wire "tail". (Bond with polystyrene cement this time!)

Drop the 1mm diameter magnet in the open end and seal that with another polystyrene plug.

I would then coat the whole thing with a thin coat of Araldite, to ensure a strong waterproof shell (for use at depth). NO! A bit of bog paper! impregnate it with resin and wrap it round the booby (SMOOTHLY!) That will provide a very strong encapsulation!

Now this whole thing could be fairly easily fitted in the body of an artificial Shad, or Muppet. Actually it wouldn't be particularly necessary. Just whip the booby on to the line in front of the Shad/Eddystone! (you would only need an odd mm of "tail" in this case.

Now use the whole rig as a jig, or jerk it on the drift over the reef!..... to get the magnet working backward and forward in the windings.......

My bet is that the predators will go mad for this!

My drummers, like professional booby beads, work a treat, as I find when comparing catches on board! With the small electrical charge, the moving magnet will produce in the coil, I should have a pretty devastating weapon!

......... no batteries required.............

NOW! Before the intelligensia start in on the efficiency, or lack of it, in the electrical generation, I KNOW! ......... But you don't need much potential to attract the preds!

[wayner]

There's only one way to find out? Make a few up & try them out, see if they have a higher hit rate then a normal lure. Sounds a little 'Heath Robinson' but very interesting all the same.

[olsmelly]

Heath Robinson?!?!?!?!
:bash:

:crazy:

Simple, tried physics my son!......... and simple to make. The only issue is to whether it would benefit from a copper sleeve between the magnet and the coil! As described, the magnet will quickly erode the insulative coating on the inner coil.

YES! A copper sleeve, instead of a plastic former! A magnetic bead instead of a magnetic cylinder. That will introduce a random factor to the electrical charge. That will be more realistic!

A bead will allow the whole thing to be much more compact, so it will resist deep water pressures much better.

It has to remain fully waterproof.

I will actually encapsulate it in fibreglass "paper", which will make it virtually bulletproof! In fact the whole unit will be quite nicely engineered!

;D

[Canuck]

Just this minute watchimg a James May program on sky about sharks, they put a tube into the water and pumped in some fish blood immediately the sharks swam in and got excited. Then they switched on an electric current between 2 electrodes fixed to the bottom powered by a pp7 battery the sharks left the blood and went over and started biting the electrodes. So there is something about electricity / electric fields that may be worth exploring.

Rich

[wayner]

Sorry, actually find the premise quite facinating.

[olsmelly]

Oh! I'm confident it works! Although your reference enhances that confidence, for which I thank you.

The fact that a pp7 voltage is enough is also a bonus!

That means that I only need a hundred or so turns in the coil, say, 200; four layers of 50.

It is essential that the casing of the booby is high resistance and only one terminal is exposed to water. Polystyrene is a "leaky" insulator; meaning that there will be sufficient leakage to drain each electrical pulse, but not enough for a short circuit. The whole thing relies on a low current and relatively low voltage.

You wanna catch 'em, not electrocute 'em!

Your input has also convinced me to use small magnetic beads, as opposed to larger bar magnets.

That all saves money. I can buy in 100 beads for £6.00. The copper tube for 100 units costs £3.32 and the poly around £4.00. The lacquered wire another £2.50. Add a couple of squid for adhesives and resin and that works out at , what?......... say £12.00 for 100 units, or 12p each!

That's a bit cheaper than these super-tech "professional" jobs! (I put the professional in quotes, because I am a retired radio engineer, so my opinion is also professional).

[olsmelly]

No need to apologise Wayner! I was extracting the Michael!
:peace:

I just might make a load and farm them out to you guys through the website.

I find the prototype is always a bit ropey. My efforts become much better with a bit of practice....... and at 12p each.......... well........
:cheers:

[martyng]

Quite an interesting thread Rattling lures certainly work better in certain situations than silent lures, so a rattling lure that generates a magnetic field too has theoretical advantages over 'traditional' lures.

Please let us know how the tests work out as anything that gives me an edge.....

[olsmelly]

Hi martyng!
Actually the operative bit is the small electrical charge, caused by the movement of the magnet through the wire coil. All fish generate minute electrical fields, due to the operation of their musculature. Fish in distress emit "clicks", generated in their swim bladders.

I don't know if a moving magnetic field will have any effect. Even if the device works (of which I have no doubt) I will never know if the magnetic bit has any effect, except to generate the electrical charge!

One thing is for sure. I am not spend sixteen squid on a gimmicky light and electric show, when I can make something as effective for 12p!

[stingraymaster]

sounds good

[martyng]

Aug 28, 2009 9:37:07 GMT olsmelly said:

Hi martyng!
Actually the operative bit is the small electrical charge, caused by the movement of the magnet through the wire coil. All fish generate minute electrical fields, due to the operation of their musculature. Fish in distress emit "clicks", generated in their swim bladders.

I don't know if a moving magnetic field will have any effect. Even if the device works (of which I have no doubt) I will never know if the magnetic bit has any effect, except to generate the electrical charge!

No problems I understand the concept of induction and generating electricity using a moving magnet.

I am interested in how you are going to try and create the field around the plug. I was thinking of an electrode attached to the hooks and another to ground/seawater allowing a field to be created between the two....

P.S. Just been looking at an American patent that uses a rolling steel ball and a piezoelectric crystal to generate the field. Wonder if that was ever developed into a working lure?

[olsmelly]

The field is basically an electrostatic one. However, I am not going to explain that bit!


I thought of the piezoelectric idea, but, as I said in another post, we wanna catch 'em, not electrocute 'em! The problem with using piezoelectrics is that the static output is in THOUSANDS of volts! Piezoelectric impulses are widely used in ENS (a form of pain limitation) I have one beside me right now. The output, in a fish's mouth would stun it at least and kill it at worst!

I am being practical about how much of a field a fry can actually generate. The posting about May's TV experiment last night tells it all!

There are other issues, like the application of pressure to the crystal. Whilst crystals will survive pressure for many years, they will soon disintegrate under hammer blows.

You might be interested to hear that I have the prototype material costs down to about 6.5p. The windings will actually cost me £8.36 for 1500m of wire! So even using 2m per unit (which is a load of overkill, 'cos I'm looking at about 8-900mm per unit) that item will cost under 1p per unit.

Since I'm talking retail prices here, I know I can get material prices down to about 3p per unit, retail! That will make 'em "throw away" items, if they ever come to the market. I was discussing all up costings with Maw last night. I reckon that for me to make a run of prototypes, the all up costs, including my labour, will come in at about 50p per unit, applying standard criteria. Automated commercial production in bulk will take that down to about 25p per unit. Applying standard overheads for marketing and distribution, I can see 'em coming on the market for an RRP of about 90p., as a stand-alone unit and about £1.50 in Shad format.

The major issue will be the construction of deep water units, which will need to resist water pressures encountered at 300+ft. depth. I am thinking in terms of a sophisticated deep water jig, or perk, for those BIG Halibut! (when you've had a close encounter with a 5cwt Halibut, you get a yearning!)

Maw is pretty enthusiastic about the idea. As she rightly points out, there is no patent in this. However, I can protect it with a design registration, which is why I'm not telling how the field gets generated!

[olsmelly]

I have sourced and bought the basic raw materials, which should be delivered around Wednesday.

I shall be making about 30-50, for trial. The overall dimensions of the unit will be approximately 25mm x 10mm. (1" x 1/4")

So anybody who wants a couple for trial, get yer name down now. I'm looking for 10 volunteers from around the country. The only condition for receipt is to write a review on this website within 2 months.

I'd prefer an initial report within a month of receipt, with a couple of updates.

Contact and distribution will be via the webmaster.

[olsmelly]

Further to the piezoelectric mention: "electric fish" emit between 10 and 500 volts. "Weak-electric" fish emit electrical fields of less than 1 volt.

Non-electric fish emit far less than that. We are probably talking in millivolts.

Time will tell.

[olsmelly]

I make no apology for bumping my gums about this subject, because the more I find out about the subject, the more fascinating it becomes.

The main issues, in my mind, with respect to the design of an electrical attractor, is the amplitude of impulse, required, the frequency (if applicable) and what fish might be more susceptible to such a lure.

Taking the last first, the main targets appear to be sharks and rays (cousins) and eels. So I shall certainly be trying the lure out on smoothhounds and conger.

The amplitude of impulse is actually minute, as it turns out. Sharks can detect impulses in the order of micro volts, so my design can be quite small, to achieve results. This is actually helpful, in terms of electronic design (but I'll keep that bit under my bald spot for the time being).

There is also the issue of alarm signals of fish under attack and stress.

We all know that distressed fish make clicking sounds, using their swim bladders. We also know that all fish create minute electrical fields, due to their heartbeats.

As we all know, heart rate can be controlled by electrical pacemakers. Heart muscles (similar in all animals and fish) generate their own impulses. Now I am wondering if alarm signals in fish might modify these impulses.

In animals, stress produces adrenaline, which increases heart rate and circulation. However, in fish, blood circulation is much more rudimentary. Whilst it provides a distribution path for nutrients, it does not supply them directly to musculature, as our capillary system does. Piscatorial circulation is more through diffusion.

That means that they probably need a different muscle stimulus to adrenaline. That could actually be related to the clicks in the swim bladder.

The swim bladder is physically linked to the brain of the fish. Pressurise the bladder and you paralyse it. This common (if unrealised) phenomenon results in the premature discard of many domestic aquarium fish, which get overfed! Fish, suffering from excessive wind (they do fart!) experience swelling of the gut. This exerts pressure on the swim bladder, paralysing the fish. They then float, helpless, near the surface of the aquarium.

Most fish, if left floating, will recover in a couple of days. Most get flushed down the toilet long before that.

So what if the clicks are also a stimulus to the brain, to produce more and stronger muscle activity!

The resulting stress impulses will be synchronised to the clicks.

Only a hypothesis, but a reasonable one.

I am getting quite excited now..........

.......... and here is some light reading for the more erudite.......

epore.mit.edu/papers/1998_6.pdf