Litz wire

[daverave]

i want to make a light weight coil for my minelab elite...is this possible for me to do ?????

[STORMTHOR]

A coil wound in a crisscross manner to reduce distributed capacitance. Also known as duolateral coil; lattice-wound coil.

[WM6]

There are some other opinions too (see Woody comments):

http://www.invisionplus.net/forums/index.php?mforum=goldprospecting&showtopic=5810&hl=#

[WM6]

Yes from some of my old radio days,Litz wire was Square for max surface area coverage in multistrand an cotton covered. very nice to see these pics. Now some of the later day detractors to what litz wires mean physical can see!the range of difference,all under the term Litz wires an know.
Coil winding an development may have taken a bit of a retarded trend to what it once was,with such a narrow focus on just the generic wires we use today an poor use of science an understanding.Wish you all well anyway with your various coil developments.
regards Rov

Exactly as you say Rov. Thanks Cyclonite to remember us.

[detectormods]

Gday Rov The Resistor value in Ohms after i unsoldered it was 0.6 Ohms. Also with the resistor out the uH was 500 uh with resistor back in the reading was 300uH. I think the 0.5 Ohms stayed the same resistor in or out i didn't write it down. I didn't measure each loop of wire. The two loops of wire one was litz multistrand the other one was signal strand very thin wire that's the one that broke of. To hard to count how many turns there were. Shielding was like you said graphite paper. Also had a earth wire taped to the graphite paper. I didn't take a photo of it before i fixed it and glued it back together didn't think of it. Hope this makes sense to you. I don't know much about making coil yet still thinking about making one. I do have 14" DD coiltec coil that is a bit noisy I should cut it open and see if it is a easy fix as well if i do i will take a photo of it and put it on here.
Thanks mate.

You should check that resistor value again, it should be 500 ohm and is placed across the receive winding on a DD. The reason a resistor is used is that a residual voltage is coupled onto the winding from the transmit coil that overloads the input amplifiers, the resistor decreases the stray voltage to an acceptable level.

If you could properly isolate the transmit and receive winding so there was no cross coupling then it would be a much more efficient coil, the resistor kills off some of the signal and thus sensitivity suffers.

[Cyclonite]

Soldering Time and Temperature of Litz Wire

I have re-edited the original articles table from HM Wire International to metric standards. The difference in AWG size conversion to Inches and Millimeters, are due to the Litz Wires Enamel Layer, which adds extra thickness to the strands.

Included in the Table are:

Inches to Millimeters
Fahrenheit to Celsius

Attachment:

Soldering of Litz Wire (HM Wire International).pdf (Original Table)
Soldering Time and Temperature of Litz Wire (litz-wire).pdf (Re-Edited Table)

as

Soldering of Litz Wire.rar

Regards,

Robert

[Cyclonite]

... Coil Winding an development may have taken a bit of a retarded trend to what it once was,with such a narrow focus on just the generic wires we use today an poor use of science an understanding. Wish you all well anyway with your various coil developments.
regards Rov

Hi @Rov,

Then it's about time that we do something about this "Retarded Trend", and get back into gear. I am a Tube (Valve) fanatic, ... and Old Habits Die Hard!

How about starting off with a Simple Honeycomb Coil?

Naah, ... thats just too easy!

Build a Universal Coil Winding Machine - By David J. Gingery (1991)

Regards,

Robert

Attachment:

Simple Honeycomb Coil

[Rov]

Yes from some of my old radio days,Litz wire was Square for max surface area coverage in multistrand an cotton covered. very nice to see these pics. Now some of the later day detractors to what litz wires mean physical can see!the range of difference,all under the term Litz wires an know.
Coil winding an development may have taken a bit of a retarded trend to what it once was,with such a narrow focus on just the generic wires we use today an poor use of science an understanding.Wish you all well anyway with your various coil developments.
regards Rov

[Cyclonite]

Gday Rov
... Shielding was like you said graphite paper. Also had a earth wire taped to the graphite paper. I didn't take a photo of it before i fixed it and glued it back together didn't think of it. ...

This is what I found on YouTube on MineLabe's Search Coil. Here you can clearly see the Graphite Paper Shielding:

Inside a MineLab Metal Detector Coil for P.I (2m36s):

http://www.youtube.com/watch?v=BY7WFyCVO_A

Also, one more YouTube Video on "How to Repair Faulty Metal Detector Coils":

How to Repair Faulty Metal Detector Coils (5m42s):

http://www.youtube.com/watch?v=0OwrkEOpPiQ&feature=related

Enjoy!

Robert

[Cyclonite]

Litz Wire

Litz Wire Manufacturer and Information

LITZ-WIRE.com (see Litz Wire Images below):

http://www.litz-wire.com/

I have made a PDF-File of there Technical Information added as Attachment, which can also be found here on there WebSite in HTML-Format:

Litz Wire Technical Information:

http://www.litz-wire.com/technical.html

Interesting however, is a Table that shows the recommended Frequency VS. Wire Gauges. It seemingly looks like they recommend far thinner Wire Strands than you would expect from the depth of Skineffect Penetration for a given Frequency range for a Single Wire Strand.

Skin Effect Calculations:

http://www.sigcon.com/Pubs/news/skineffect.htm

But probably the explanation lies here:

For the stranded and Litz wires we need to take the stranding and the effect of inter-strand contacts or insulation into account.

Skin Effect and Cable Impedance:
http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/skineffect/page1.html

Regards,

Robert

Attachment:

Litz Wire Technical Information.pdf

[Cyclonite]

You may want to check this link out about Graphite Paper!

Graphite Paper

Regards,

Robert

[delete52]

Gday Rov The Resistor value in Ohms after i unsoldered it was 0.6 Ohms. Also with the resistor out the uH was 500 uh with resistor back in the reading was 300uH. I think the 0.5 Ohms stayed the same resistor in or out i didn't write it down. I didn't measure each loop of wire. The two loops of wire one was litz multistrand the other one was signal strand very thin wire that's the one that broke of. To hard to count how many turns there were. Shielding was like you said graphite paper. Also had a earth wire taped to the graphite paper. I didn't take a photo of it before i fixed it and glued it back together didn't think of it. Hope this makes sense to you. I don't know much about making coil yet still thinking about making one. I do have 14" DD coiltec coil that is a bit noisy I should cut it open and see if it is a easy fix as well if i do i will take a photo of it and put it on here.
Thanks mate.

[Rov]

Resistor,what is the value of this in Ohms? What are the other specs. you measure for each loop of the DD. also what wire did you find inside,multistrand? an of course the shielding would be the typical graphite paper sheet that minelab uses in their coils.true! Thanks,U got a pic for what you found?

[delete52]

litz wire

Hi A mate gave me a 11" minelab dd coil that didn't work so i pulled it apart and one of the wires was broken off. I was surprised to see a resistor on one of the wires so dose that mean that a resistor can be used to get the right ohms reading?
Thanks

[IBGold]

Hi delete52,
It's a long learning curve but eventually you will get there where in Aus. are you I am in S.A. wait until you try DD's that's a challenge.
Regards, Ian.