What is the relationship of uH and sensitivity?

[wam]

... I don't really need more depth, what I need is more width

Hi, for the more width You need to try a biger coil, the best DD type, suitable for the same VLF frequency as your detector. Get some second hand one. It will be better if the TX side inductance is close to Yours detector. The RX inductance the best to be the same as original detector but it is not so critical. You will need to make adapter box to connect pins from "try" coil with yours detector. Available coils may not have so much depth but width should be better.

If You want to make coil on your own, then study and copy some coil building project and ask for advice how to temper given project so it will have desired VLF frequency. Number of turns for the same L will be smaller for biger size. Start project before winter so it can be ready for summer.

I have detector with coil about 1.4 mH TX, and 80 mH RX, 6.5 kHz, I will try it with number of "western" coils but it will be some time latter so keep looking, trying, making and learning. Dont forget to tell us about improvments ...
In general on RX side more uH means more sensetivity but it is not so simple on TX side.
Regards.

[erdin]

did you ever do any thing with it? I also have a cheap detector that i want to play with.