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Blue e-field antenna question - Printable Version

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Blue e-field antenna question - llowrey - 2021-07-05

Hello,

The documentation for the Blue kit indicates that one can use the 'built-in' antenna and includes a photo of the PCB with the rectangular section opposite the antenna screw terminal, and labeled 'Probe / Antenna' below, still attached. That rectangular section is not electrically connected to the e-field board.

[attachment=4491]

It's been 25+ years since my coursework in electromagnetics so I'm a bit ignorant at this point. Is that separate rectangular section coupled in some way even though it is not electrically connected?

What, exactly, is the 'built-in' antenna?

Is it preferred to use a wire instead of the 'built-in' antenna?


RE: Blue e-field antenna question - dupreezd - 2021-07-05

(2021-07-05, 18:40)llowrey Wrote: Hello,

The documentation for the Blue kit indicates that one can use the 'built-in' antenna and includes a photo of the PCB with the rectangular section opposite the antenna screw terminal, and labeled 'Probe / Antenna' below, still attached. That rectangular section is not electrically connected to the e-field board.



It's been 25+ years since my coursework in electromagnetics so I'm a bit ignorant at this point. Is that separate rectangular section coupled in some way even though it is not electrically connected?

What, exactly, is the 'built-in' antenna?

Is it preferred to use a wire instead of the 'built-in' antenna?
llowrey, the top part is electrically connected to the bottom part, however in the past there where some that was not.
To be certain that yours are, measure it using a DVM set to Ohms.
The best however, is to use a 100mm, 14 gauge solid copper electric wire. Connect it to the inner screw connector.

Remember to update your BO profile using Input 3. Inputs 0 - 2 is used for the H field.


RE: Blue e-field antenna question - llowrey - 2021-07-06

Thank you for your reply.

Mine (17.2) is definitely not connected. I did check with a DVM, but more importantly, using a bright light I can see clearly that there is no copper spanning the bridge between the two sections.

Regarding placement, I believe I read that the e-field antenna can be placed above a metal roof and the h-field can be placed under a metal roof. Is that true and if so, is there a minimum distance that they should be away from the roof?

The roof in question covers a concrete pad and is away from the house and any electrical wires, devices or machinery. It is about 12' (~3.7m) above the ground. I could place either in a nearby tree about 20' up (~6m) if that would be meaningfully better.