Coil shielding and screen mesh size

[GT Blocker]

First I would like to say howdy to all of you who have posted on this forum and thereby softened my journey considerably.
After several days of study on these boards I do have a question that I hope someone has an answer to.
Since all screen comes in a mesh, i.e. 40, 100, etc., how small of mesh size would be sufficient to shield the coil (I'm building Carl's HH, BTW). I realize that metals with ferrous, or magnetic (nickel) properties are prob a no-no.
I am striving for the lowest sample time I can reach as I detect for gold here in AZ (Black Canyon City, if anyone is close...). I was considering a fairly fine copper or brass screen of say around 60 mesh. Bad idea, or? Thanks, GTB

One other thing....Can my ML Eureka Gold be used to excite my home made coil for impedence and resonant freq testing?

[Molzar]

Hi GT Blocker,

I used Scotch 24 mesh sheild tape. This is hard to find (but not impossible).

I think most brass / copper mesh would be too thick and would degrade performance, especially if you want short delays.

Aluminum (real Aluminum) duct tape works well also.

How you read BBsailors coil artical? Really excellent this is where the Scotch 24 idea comes from. http://geotech.thunting.com/pages/me...s/FastCoil.pdf

There are also plenty of other threads on shielding to read here.

Good luck,

Molzar

[GT Blocker]

DD shielding question

Boy was I a newbie when I started this thread...jeeze....

I'm still just as bad, since:

I was wondering why the transmit coil in a PI DD configuration needs to be shielded. Isn't the rec coil the only one affected by outside noise as far as the front end amp is concerned?

Just wondering (aloud, I guess...)
Thanks, GTB