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+--- Thread: Blue e-field antenna question (/showthread.php?tid=3490)
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,llowrey, the top part is electrically connected to the bottom part, however in the past there where some that was not.
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?
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.