Shield the E-probe?
#6
Based on the Pesky Project gallery pics/text, and the current shipping ferrite core diameter of approx 10mm (actual core, not as wrapped and heatshrink added), the spacing between the outside of the core and the shield should be approx. 10mm x 10 (stated multiple) = 100mm

1) Is 100 mm correct?

2) Would a round shield housing offer any benefit over a square housing?  Obviously, square is easier to construct/prototype, but I'm asking about performance...

3) The gap distance shown is 2-4 mm...  That's a pretty big range...  What is the theory behind sizing the gap?  Would it be based on the frequency and polarization of the "noise" vs. "desired" signal?
3a) Does the gap function as an admission aperture?

4) How should the gap be oriented?  Does it matter? Say a ferrite that is long axis oriented E/W to generally receive N/S signals....  Gap Up? Down? North? South?

4a) Would there be any benefit (on horizontally oriented ferrites rcving vert polarized sigs) to having TWO gaps oriented in the 2 cardinal directions the ferrite favors?  (Of course, you'd need to bong GND to both halves, or bond the halves together at both ends on the "far side".

5) When using the third ferrite oriented vertically, which would favor receiving horizontally polarized signals, how would you orient the gap? How many gaps?  1, 2, 4?  Intuitively, I'm lead toward 4 as a minimum... oriented N,S,E,W...  Or 6, oriented every 60 degrees.... Or 8, every 45....  How many gaps before the shield is rendered less than useful.

Crap....  it just occurred to me that I am too ignorant of the basics in this particular subject to converse intelligently about shield theory, design, optimization for H-filed ferrite antennas.
It would appear I have just added a couple thousand pages of reading to my list...  Wink
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Messages In This Thread
Shield the E-probe? - by Max_Headroom - 2017-04-22, 14:54
RE: Shield the E-probe? - by cutty - 2017-04-22, 15:57
RE: Shield the E-probe? - by Max_Headroom - 2017-04-29, 14:16
RE: Shield the E-probe? - by RichoAnd - 2017-04-29, 15:19
RE: Shield the E-probe? - by Max_Headroom - 2017-04-29, 18:34
RE: Shield the E-probe? - by KY5G - 2017-10-15, 17:42
RE: Shield the E-probe? - by readbueno - 2017-10-15, 19:26
RE: Shield the E-probe? - by cutty - 2017-10-15, 21:11
RE: Shield the E-probe? - by KY5G - 2017-10-16, 22:05
RE: Shield the E-probe? - by cutty - 2017-10-16, 23:34
RE: Shield the E-probe? - by KY5G - 2017-11-01, 17:54
RE: Shield the E-probe? - by RichoAnd - 2017-10-17, 05:44
RE: Shield the E-probe? - by KY5G - 2017-11-01, 18:01

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