DIY Mad Litz Wire for ULTRA FAST PI Coils

[bbsailor]

Thank you. So that correspond to AWG28, not the very commonly used awg24 i can see in most of the surf pi posts?Or awg 28 applies only for the litz?

Look up on the web “wire skin effect”. This will explain how as the frequency gets higher the less penetration to the center of the wire.

In in relation to PI metal detectors is the minimum delay you need for detecting very small targets. At very low delays the coil wire itself can hold eddy currents. If your delay is set to a lower value than the coil retained eddy currents, the coil wire will respond like a target.

The Litz wire stranding related to frequency is a way to get the required coil wire gauge size to carry the required current but also select a stranding size to use the full potential of each strand at the operational frequency range but to also minimize the wire bundle from holding larger amounts of eddy currents if the wire were a solid larger diameter type of wire or the strands were too large for the frequency range.

The key test is to test wire samples an inch or two long and see if they respond like a target at your lowest delay. Litz wire is a wire type that uses each strand in parallel to carry the required current but also minimize any retained eddy currents in the individual small strands.

Joseph J. Rogowski

[Melbeta]

This brings up a question in my mind. Would it be better to use a solid wire? If not, what kind of wire would you suggest?
Melbeta

[bbsailor]

This brings up a question in my mind. Would it be better to use a solid wire? If not, what kind of wire would you suggest?
Melbeta

The thickest solid wire I have used with a delay of about 8uS is AWG 30. This was a low power CS6PI that had a 39 Ohm resistor in series with the coil so carrying a high current was not an issue. If I had to use a thicker wire I would look at tinned stranded copper marine wire as there is a slight resistance between the strands and this minimizes the eddy currents forming in a thicker solid wire or silver plated strands that have a low resistance between strands that tend to support holding eddy currents longer. Try to find an insulation with the lowest dielectric constant to make a coil with minimal coil turn-to-turn capacitance. PVC insulation dielectric constant ranges from 4 To 6 while PTFE (Teflon) is 2 and PE is about 2.2.

I hope this answers your question?

Joseph J. Rogowski

[nonkapo]

Thanks, Joseph, i read about and your explanation in my other posts was more than clear. I just try to get which litz wire gauge corresponds to solid or stranded wire gauge. I mean if as you say awg30 is the maximum one should use is this valid for Litz as well?

[Melbeta]

Thanks Joe,
I am not interested in Pulse detectors, but like the VLF machines. I am trying to glean all that I can in regard to making coils, so I am asking questions to learn what I can learn. What wiring is best for VLF machines?
Melbeta

[bbsailor]

Thanks Joe,
I am not interested in Pulse detectors, but like the VLF machines. I am trying to glean all that I can in regard to making coils, so I am asking questions to learn what I can learn. What wiring is best for VLF machines?
Melbeta

This question is probably best answered by Carl or Qiaozhi.

The issues are usually related to operational frequency and reduction of losses to increase coil radiation and efficiency.

Joseph J. Rogowski

[Andi68]

So I prefer to buy this litz wire before I go crazy with such housewife work

[phred01]

Thanks Joe,
I am not interested in Pulse detectors, but like the VLF machines. I am trying to glean all that I can in regard to making coils, so I am asking questions to learn what I can learn. What wiring is best for VLF machines?
Melbeta

Litz wire would help with VLF machines. the coil & a capacitor are part of an oscillator. The coil is made of two components .....inductance & effective resistance. By reducing the resistance by using litz wire The LC circuits Q is increased therefore smaller items can be detected more easily
L

[Melbeta]

Well, at least now I know the theory regarding the use or non-use of Litz wire for VLF detectors. Thanks.

What is LITZ wire anyway? I know there is a coated wire used for transformers. Could that be used?
Melbeta

[Andi68]

http://www.elektrisola.com/hf-litz-wire.html

For example its used in transformers of Swichtmode powersupplies.

[dbanner]

I recently saw a simple rig for making litz wire. Somewhere on Russian metal detector review forum. Will see if I can find it again.

[dbanner]

Here it is. The wires feed through the nozzle of the plastic bottle. Then I guess you have to twist them together with drill.

[dbanner]

Looks like absolute madness if something goes wrong.

[Andi68]

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