On 12/8/21 2:53 AM, Terry Fritz wrote:
>
> Hi Paul,
>
> Interesting!
>
> Pearson curent probes are fully shileded but the sheid acts as a shorted turn near the primary. All that 90 degree stuff is really imprortant near the primary. I think remote location is a big help for those new people that not brave (stupid enough :D ) to locate scope probes near coils.
>
> I love E-field probes. They just work! I just had to whip up another for myself since all the folks I lend them to never bring them back :D
>
> https://ibb.co/YL99n1H
>
> Good thought about field probe interference. I don't think most folks who care much about fine details. But for true science it would me a major factor.
>
> Who would ever waist time on dividers!!!!
>
I think most folks are interested in waveforms, not absolutely
calibrated voltages. The e field probe approach gives you exactly that.
(well, a lot depends on where the probe is - does it "see" things
other than the topload (like the secondary), and is there a significant
phase shift between top and bottom of secondary. I don't think so. The
"slow wave structure" advocates say yes there is - this is not by any
means tesla coilers only - the same discussion happens when talking
about loading coils on antennas.
And, of course, it's difficult to adequately instrument. Maybe leads
made of semiconductive paper aka spacecloth (377 ohms/square, like free
space) leading to a divider at some distance?