Voodoo Main Discussion

[SilverSurfer17]

And whats weird is i used a 3 1/2 inch form he said 3 1/4 and i typed in for 30 gauge instead of 32 gauge but its the same exact amount of turns to get the same inductance

[SilverSurfer17]

thats what i typed in and wound ten extra turns but ended up with 28MH ?

[SilverSurfer17]

this is coil i started building but instead of 22 gauge i used 20 its what i had for the tx coil and for the rx i used 30 instead of 32 and he made his rx 3 1/4 inches i made mine 3 1/2 and i thought when i would put it in the coil calc it would come out with more inductance then he got because i used 1 sized thicker wire and would just take a turn or two off to get the same inductance but its not its 450 turns and is 28 instead of 35MH

[6666]

Hi 6666,
thank you for share this informations.
I think that DRS coil type could be suitable to the Woodoo principle. Very interesting cue.

Your welcome, please let us know any results if you try it, thanks

[Altair]

I just noticed who ever made the diagram labelled it wrong. its DRS, but they make a machine called "Ground Exper PRO" which is what I search on, there is a lot of info on them.
Basicly with the coil, look at the marks, for any given TX coil, the RX length = the radius , the RX width = half the radius, so for an 8 inch TX the RX would be 4x2, for PI the TX can be 300uH, the RX can be 300-450uH, and adjust for IB .
For the Voodoo I will be trying TX 300uH, RX about 1.2mH plus cap and see if it will IB,
to print the ellipse shape I use https://www.rapidresizer.com/home/20...ne-shape-maker

Hi 6666,
thank you for share this informations.
I think that DRS coil type could be suitable to the Woodoo principle. Very interesting cue.

[surfdetector]

I just noticed who ever made the diagram labelled it wrong. its DRS, but they make a machine called "Ground Exper PRO" which is what I search on, there is a lot of info on them.
Basicly with the coil, look at the marks, for any given TX coil, the RX length = the radius , the RX width = half the radius, so for an 8 inch TX the RX would be 4x2, for PI the TX can be 300uH, the RX can be 300-450uH, and adjust for IB .
For the Voodoo I will be trying TX 300uH, RX about 1.2mH plus cap and see if it will IB,
to print the ellipse shape I use https://www.rapidresizer.com/home/20...ne-shape-maker

The shape maker tool is very handy.
Cheers

[6666]

Thanks for the diagram. Have you made one of these? I would be interested in knowing some specs. Thanks again.

I just noticed who ever made the diagram labelled it wrong. its DRS, but they make a machine called "Ground Exper PRO" which is what I search on, there is a lot of info on them.
Basicly with the coil, look at the marks, for any given TX coil, the RX length = the radius , the RX width = half the radius, so for an 8 inch TX the RX would be 4x2, for PI the TX can be 300uH, the RX can be 300-450uH, and adjust for IB .
For the Voodoo I will be trying TX 300uH, RX about 1.2mH plus cap and see if it will IB,
to print the ellipse shape I use https://www.rapidresizer.com/home/20...ne-shape-maker

[surfdetector]

yep, take note of the marks they give the relative dimensions. DSR make an all singing all dancing imaging detector.

Thanks for the diagram. Have you made one of these? I would be interested in knowing some specs. Thanks again.

[6666]

@6666 I did a search for DSR coil and did not find anything. I would like to learn about these if you could point me towards some information. Thanks.

yep, take note of the marks they give the relative dimensions. DSR make an all singing all dancing imaging detector.

[surfdetector]

Have you considered a DSR coil ? they are IB and very easy to make.

@6666 I did a search for DSR coil and did not find anything. I would like to learn about these if you could point me towards some information. Thanks.

[ivconic]

I'll stay with Omega coil by now.

[6666]

I haven't tried such coil so far.
Balancing seems too complicated for me.
Even "CC" coil is too complicated to balance... in these conditions.
Truth is; the other day i prepared former for CC coil.
I had enclosure from before, i only 3D printed former for RX and former for bucking coil.
Enclosure is big enough to fit 25-27cm TX coil.
And dimensions of RX and bucking former are on the pics:

[ATTACH]54243[/ATTACH]
[ATTACH]54244[/ATTACH]
[ATTACH]54245[/ATTACH]
[ATTACH]54246[/ATTACH]
[ATTACH]54247[/ATTACH]
[ATTACH]54248[/ATTACH]

Have you considered a DSR coil ? they are IB and very easy to make.

[6666]

Yes . 3 superimposed coils Rx- / Tx / Rx +. I made one for the test. But not had good functioning. failed to make the Rx "invisible" on the oscilloscope. If anyone here knows this method, I'm very happy if he explains how to do it, or what I've done wrong ... but for voodoo it would be a good idea.

Hi lamoiz, thanks reply, would your pancake coil also be known as coaxial coil , some years ago Aziz did some work on coaxial coils he called it his "top hat coil", been looking for his posts about it, but I think he found he had to separate the coil windings by 80-90mm in height.

[SilverSurfer17]

Yeah maybe ill use fiberglass then i hate working with it but i don't want anything hindering it and ill tune it then back it up then glue it down from the posts I'm reading on the coil i think it said 11 loops but I'm gonna leave lots of extra im not doing it exactly how he did his anyway so im sure its all gonna be different i have a lot of 30 gauge wire from making Tesla coils so im gonna make a bunch of coils and mess with around with different shapes and spreading the wires around to figure out what does what

[dfbowers]

I didn't know carbon fiber was conductive i know it uses some kind of 2 part epoxy ill have to check it i was going to make a form get it all tuned then wrap it with brown paper bag painted with that guitar paint then wrap something to insulate it then wrap it in carbon fiber then epoxy it all in place where its tuned i can make a extra leg for extra bucking coil wires im still kinda unsure on the bucking coil if thats a separate coil or is that extended of the outer loop i think its outer and its using the bucking coil to help the inner pickup the signal the diagram im looking at uses three different colors for coils it also says keep extra wire because you will have to add a few turns to the inner coil because the bucking coil will change it after the bucking coil is added

Carbon fiber is bad news for things like RC drones as it can block RF from the antennas. I don't know about detector shells but it wouldn't be a choice of mine.
The bucking coil is not a big deal as you only need 5 - 6 turns to cancel out the main coil. Just continue winding the end of the TX wire the opposite direction around the RX coil.
Thing is, you will almost always end up with some fraction of a turn at the end and you need to stop when you hit the null of the coil or it will be no good. I usually double back the other direction against the TX coil when I get the null, or leave a small loop of wire at the end, under the tabs area and move it around and glue it down to do the fine tuning.