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ANTENTOP- 01- 2008, # 010

Atmospheric Current: Practical Experiments

 

Other experiment I made in summer, in hot weather (+28 C) at weak wind. Broom was made from a steel wire rope. The rope contained 49 steel wires, I untwisted the rope in length near 20 centimeter.

 

Figure 1 "Broom- Rope Antenna."

 

 

 

Figure 1 Broom- Rope Antenna from the untwisted rope

 

Broom was fixed on the end of the 7-meter fishing tackle, end of this one was fixed to a dry pine pole. The mast of 12 meters length was fixed to the bungalow, so the Broom Antenna was at 9 meters over grounded metal roof. Figure 2 shows the design.

 

A thin insulated wire was going from the Broom to the "plus" of the multimeter, "minus" of the multimeter was connected with the ground. A capacitor 4-mkFx250-V having very low leaking was connected to bridge to the multimeter probes. The capacitor shunts RF and filters fast fluctuation of the antenna current. Now the antenna current was measured for sure. The current was +0.15 nano-A at with some unexpectedly big fluctuations. Several hours of measurement showed that max current was several nano-A (Figure 3). Sometimes the current changed the polarity, I observed minus 0.3 nano-A. The antenna current fluctuations may be caused by wind that moves air areas with different volumetric charge around Broom Antenna.

 

 

 

Figure 2 Broom Antenna in the night sky

 

Conclusion 2: Current from the Broom to the antenna wire is existed and prove the "quite" discharge from ends of broom wires. The current is very unstable by amplitude and may change polarity at clear weather. Ever simple digital multimeter can measure the current.

 

There are no doubts that "quiet" discharge has an area with a negative resistance. It is possible to find lots data about it in the Internet. Figure 4 (taken from Reference 2) shows a Volt/ Ampere diagram of such discharge. Almost the same diagram you may find at Reference 3.

 

Take attention that at the left area there are nano-Ampere current area. It is so-called "quite" or Townsend's discharge. At right area (arc discharge) there are current at several Amperes. Both areas have parts with a negative resistance. Nano-area begins from current near 100- nano- Ampere. However the current depends on lots conditions...

 

My experimenters (made in 2000- 2001 years) proved that discharge may began at relative low voltage and enough large distance between electrodes (see Reference 4). I did the experimenters at my table so I do not know how discharge would be flow at a Broom Antenna. At the experimenters I was observed relaxation oscillations. The oscillations were detected by the help of oscilloscope. It may be detected by ear like weak hissing. Townsend was observed this phenomenon at 20- 30s of the 20- century.

 

 

 

 

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