Litz wire, anybody?

[Mike(Mont)]

I've seen Litz wire used on a ferrite rod radio antenna. Just curious if anybody uses it and if it gives much better performance?

[Geo]

Originally Posted by Mike(Mont)

I've seen Litz wire used on a ferrite rod radio antenna. Just curious if anybody uses it and if it gives much better performance?

Hi.
Litz gives better Q. If the lrl needs hight Q then you must make coil with litz wire.
I have 2 lrls that use litz at coils and work better with it.

[Geo]

a photo.......

[Mike(Mont)]

Wish I knew more about electronics. Why do you need a high Q and why don't you always have it? Is it more useful at higher frequencies. Thanks.

[Geo]

Originally Posted by Mike(Mont)

Wish I knew more about electronics. Why do you need a high Q and why don't you always have it? Is it more useful at higher frequencies. Thanks.

Hahaha .....
Mike, wish i knew better English so to explain you....
Q is the quality factor of a coil.
If we need a "thin" bandwith must use high Q, else must use medium or low Q.
Q depended of the resistance and capacitance of the coil. I think that you will find everything about it at google..

[Mike(Mont)]

Thanks Geo. I think I understand. Narrow bandwidth means sharper tuning.

[Mike(Mont)]

Back to the drawing board...again! I made this receiver coil all one layer of windings. I guess because the coil is wider it gives a weaker, wider response, not the sharp focus. So I plan to rebuild it with the windings all in a tight bunch more like a cable instead of a ribbon. And like another one of my favorite sayings, "It all looks good on paper."

[Mike(Mont)]

See how much I know about it--I rewound the loop antenna in smaller diameter, shorter, and multi-layer and the inductance was almost the same. I was expecting the inductance to be much higher. I used the same length of wire. The coil is not as powerful but it has a nice sharp focus when pointing at the target. This thing is working pretty good now but I still need to get it out in the field for some real hunting, and that's at least a couple months away.It hits a half ounce of silver at about 75 feet on the lowest power setting. The neighbors have a large brass pipe fitting and it pulls to that at first, but after a few minutes it moves to the target. So yeah, it likes big copper. I found with too much power it is hard to ignore it. So I guess I like the litz wire now.

[Mike(Mont)]

If at first you don't succeed...you're probably about average.
If all else fails...read the instructions.
Nothing is as easy as it first appears.

You can probably fill in the next line--
It's back to the drawing board...again!

Actually I am making some progress and I am confident I am on the right track. The latest coil is a bit weak so I am going to change the former a little bigger diameter and rewind it. I could leave it as is but like in the movie "Arthur" when the bartender asked "Haven't you had enough?" and Arthur (an alcoholic) replied "I want MORE than enough!"

[Mike(Mont)]

Built the bigger diameter coil and got more power from it. Still needs some fine tuning but it's really close to where I want. I'm going to try to figure out a different coil former to make it easier to wind. But it's working and Life Is Good!

[Mike(Mont)]

Sometimes I hate myself. I guess I have an obsession disorder. I just can't stop and be happy with the project as it is. Maybe it's more like a cancer that won't stop growing. Someday I just have to say "Enough is enough!" but I can't do it so yeah, it's an illness. So I went out today searching for new coil former. Of course I had no luck at the hardware store."We don't have anything like that." is their standard response. I don't give up THAT easy. I walked all the aisles and found some fishing line on a spool. It wasn't the right size spool but it gave me the idea to go to a sporting goods store that sells fishing gear. Sure enough I found a really nice-sized spool. I guess my subconscious would not let me rest until I found this one. It's just a matter of winding it now. The old spool I'm using now works just fine but I had to add some filler on the inside to get the larger diameter and that made it difficult to wind smoothly and just more work overall and not as nice a coil--uneven windings. So now this one is just what I wanted. Life is really good.

[Mike(Mont)]

Well, I'm holding my breath. The receiver coil is a little more mH than I had planned, but at least indoors it seems to work. So tomorrow I'll get it outside and see what happens in the yard. Right now it has good power and sharp tuning. So it's "If it ain't broken, don't fix it." Maybe I can hold to that but even if I do there is no guarantee my illness is cured.

[Mike(Mont)]

Yeah, the latest coil works good. I also found out it has a sharper null than the big loop I first built. I like the null and i was using it today as well. I check for the target then turn the coil 90 degrees and see if the null lines up the same. Sort of a double check. I also found out I get a better null when i get somewhat closer to the transmitter but not too close, like about two feet away. So the next step is to start putting everything into an enclosure, well actually I need to find an enclosure first. But anyway it is to the point where I don't want to mess with it...well, at least for today!

[Mike(Mont)]

Well, my sanity was short-lived. back to business as usual. Got another coil design (spiral) I want to build just so I won't fret about never trying it. So hopefully I'll get one built and tested today if I can figure out how to build it. Going to try to put two flat pieces together with a very small gap and just wind the wire in between. The idea is to avoid all the messy glue required. Nothing is as easy as it first appears.

[Mike(Mont)]

Somebody help me! I hopelessly obsessed. Well, I scabbed together a spiral coil, hooked up, and I like the way it points, very narrow signal. It does not have a sharp null but I guess I can't be greedy and that might be because it is not tuned right. My system is apparently different than all the pistol detectors. I point to the target by the plane of the windings (that's the magnetic component), while the broadside gives me the null. It's a little bit weak but very sharp, (whereas the null is too wide for my liking). So I might try to modify it like i wish I could use some flat ribbon for the windings to get a little more solid signal. Don't even know it that will work. But I'll leave that for another day, maybe. So the answer is "No. I am not done yet." Ouch!

[Mike(Mont)]

I seem to have lost my enthusiasm for the flat spiral coil. Kinda like those gold rush 49'ers, when they hear about a new gold strike they leave their profitable diggings in hopes of something better. Got one more idea to try. Well, at least one more.