fair weather current

[Phil]

Like I said, the electronics part is trivial. However, excellent insulators are key. A wire grid of about 6 - 8 inches square makes a good detector, but you need to mount it firmly with really good insulators. Wood won't cut it, and some plastics may not be suitable either. A trailing wire to the electronics with leaky insulation (even with tens of megohms resistance) touching ground will mess up the results. A passing spider casually exploiting the grid as a web support will do likewise. Dew? Rain? Condensation? A blade of grass? No results.

Don't let me put you off - it's easy to measure this astonishing concept of a 100 V/m field, but getting high quality, reproducible results demands no little ingenuity. You have to think in terms of gigaohms and higher. Go for it.

Phil M1GWZ




On 17 Jun 2012, at 21:35, Mark Whittington wrote:

> Now I want to do this.
> 
> On Sun, Jun 17, 2012 at 9:11 AM, Phil <philmt59 at aol.com> wrote:
> An interesting subject; makes a great science-fair / school project. It's not difficult to use a MOSFET or MOSFET op-amp to track 1V/cm electric fields, using a small wire grid mounted 1 cm above the ground. You will see some interesting inversions and voltage hikes as storms approach.
> 
> Phil M1GWZ

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