Nulling concentric coil oo

[jroux]

Hi all, my coil is :6.77mH for RX 108 turns 0.25mm wire coil concentric 20 cm
TX is 5.57mH 153 turns 10cm
How many turns in opposite directory i use on tx for nulling , 35 turns ? (153:4=35)

Inductances measured with frequence meter on my original coil.

[WM6]

Check once more. Probably TX is 20cm in diameter and RX 10 cm in diameter.

[jroux]

Yes TX is 20cm diameter and Rx 10cm diameter

[jroux]

Yes TX is 20cm diameter and Rx 10cm diameter

,
I think I found how to build this coil: TX 20cm diameter 98turns of wire 0.25
RX 10cm diameter 169 turns of wire0.25
BX 24 turns wound in opposite rx.

[WM6]

,
I think I found how to build this coil: TX 20cm diameter 98turns of wire 0.25
RX 10cm diameter 169 turns of wire0.25
BX 24 turns wound in opposite rx.

You can try this your concept. There is no problem to add additional turns to bucking coil. If you found that there is some turns too much in bucking coil, usually simplest solution is to lower inductive coupling between BX and RX coil (by changing distance a litle).

[jroux]

If i understand i can change the distance of the couple bx-rx torque over tx.
tx will therefore no longer centered with respect to tx.

[WM6]

If i understand i can change the distance of the couple bx-rx torque over tx.
tx will therefore no longer centered with respect to tx.

I mean you can change coupling between bx-rx by changing distance between bx-rx.

Of course you can achieve the same effect (tunning coil) on different way and one of those is to change distance between tx and rx too.

[jroux]

Ok i understand ,thanks.