IGSL

[Koala]

Thx for replay mate.
I think my coil is not good(27 cmm coil),i try make new coil i then null coil i see on youtube they can reject ferrit with musketeer coil.
I try all night to reject ferrite,but it is mission impossible i have nice deep about 28-30 cmm small gold ring.also i did not shield my coils now i will make new one put shield and then see what will happen.

If you have a way of measuring frequency follow Don Bowers 101 instructions.

"my favorite method is just attach the coil to your completed circuit board (J1) and measure the running frequency. The Tx should run at 14.5 kHz.
Next, half of the form must be removed and the wire must be constrained. I use simple dental floss. Note: If wire is wound on a two sided form tightly, very little change in inductance will occur once constrained. At most, it should increase by only .1 mH.
Build your Rx coil in the same manner, except for the number of turns. Also, to check your Rx coil, you can attach it to your completed circuit as well, but attach your Rx coil to J1 (the Tx circuit). Since this is 6.5mH, the oscillator should now run at 13.95 kHz. Again, this is just a quick check and will then be removed! "

[seadoggy]

Not all ferrite is made equal. I find a small bit long wave Arial fine but some of the hard emi filters don't reject fully. Also you can have problems if is in a doughnut shape.

If you are almost rejecting but running out of adjustment on the ground balance POT I would suspect the phase on the coils is too far out. RX and TX normally have very similar inductance for these detectors.

Thx for replay mate.
I think my coil is not good(27 cmm coil),i try make new coil i then null coil i see on youtube they can reject ferrit with musketeer coil.
I try all night to reject ferrite,but it is mission impossible i have nice deep about 28-30 cmm small gold ring.also i did not shield my coils now i will make new one put shield and then see what will happen.

[Koala]

I cant balance coil to remove ferrite!
My TX is 1mh-(4.5 ohm)
RX-15 mh-(wire 0.20 have 77 ohm)

Not all ferrite is made equal. I find a small bit long wave Arial fine but some of the hard emi filters don't reject fully. Also you can have problems if is in a doughnut shape.

If you are almost rejecting but running out of adjustment on the ground balance POT I would suspect the phase on the coils is too far out. RX and TX normally have very similar inductance for these detectors.

[seadoggy]

Not completely reject ferrite rod, but some crack u must got near 5 cm from coil, try also hot rock, must be complete rejected, if not, u will got into instability at mineralised soil.

I cant balance coil to remove ferrite!
My TX is 1mh-(4.5 ohm)
RX-15 mh-(wire 0.20 have 77 ohm)

[CDI]

hello do IGSL must reject ferrite rod??,
my IGSL board working good,but i dont know do must reject ferrite rod when i balance coil.

Not completely reject ferrite rod, but some crack u must got near 5 cm from coil, try also hot rock, must be complete rejected, if not, u will got into instability at mineralised soil.

[seadoggy]

hello do IGSL must reject ferrite rod??,
my IGSL board working good,but i dont know do must reject ferrite rod when i balance coil.

[ivconic]

Ivica when you turn IGSL with out coil,do you get any sound on speaker??

this is my igsl
[ATTACH]34747[/ATTACH]

No.

[seadoggy]

Ivica when you turn IGSL with out coil,do you get any sound on speaker??

this is my igsl

[seadoggy]

Yes of course.

ok thx mate

[ivconic]

Can i use wire 0.20 to make RX coil for IGSL??

Yes of course.

[seadoggy]

Can i use wire 0.20 to make RX coil for IGSL??

[CDI]

All info here original project was on md4u.ru forum.

Many thank's...

[Koala]

I'm sorry for going in offtopic, can u post lay file for your Bandido?

All info here original project was on md4u.ru forum.

[CDI]

I have just built a 6" concentric for my Bandido . With small coins like silver sixpence I experience no loss of depth over a 10 DD and gain depth if the coin is on its edge. A small fibula the 6" coil just has the edge.


Only been out with it twice but when I tip my finds bag out there appear to much more of the smaller fragments than I had before.


I sacrifice 4" on larger coins but gain on coins on there edge. Only time will tell but so far so good.


Don't know if a factory 5.75" works as good.

I'm sorry for going in offtopic, can u post lay file for your Bandido?

[Koala]

I have just built a 6" concentric for my Bandido . With small coins like silver sixpence I experience no loss of depth over a 10 DD and gain depth if the coin is on its edge. A small fibula the 6" coil just has the edge.


Only been out with it twice but when I tip my finds bag out there appear to much more of the smaller fragments than I had before.


I sacrifice 4" on larger coins but gain on coins on there edge. Only time will tell but so far so good.


Don't know if a factory 5.75" works as good.