AC voltage from aluminum Grounded?

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    Ac Aluminum Voltage
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Discussion Overview

The discussion revolves around the phenomenon of measuring AC voltage from a piece of aluminum that is partially inserted into the ground. Participants explore the conditions under which this voltage is observed and speculate on potential sources and mechanisms behind the readings.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant reports measuring a consistent AC voltage of 0.8 to 1.50 Volts from aluminum inserted into the ground, noting that thicker aluminum yields higher readings.
  • Another participant questions whether a DC reading is possible and suggests testing the setup in slightly salty water, proposing that the setup may resemble an electric cell.
  • A third participant notes the absence of a DC reading and speculates that the aluminum rod could function as an antenna, with the oxide layer acting as a diode, likening the setup to a simple crystal radio circuit.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the readings and the mechanisms involved. There is no consensus on the source of the AC voltage or the implications of the findings.

Contextual Notes

Participants have not tested all suggested conditions, such as the effect of salty water, and the implications of the lack of a DC reading remain unresolved. The discussion includes assumptions about the behavior of aluminum in ground conditions and the potential for various interpretations of the observed phenomena.

THORPE
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My knowledge of AC voltage is very basic but I have a question.

I stumbled upon this by accident.

If you take a piece of aluminum, stick one one end into the ground just a little, say 1".

Then take a volt meter, stick one lead into the ground, the other lead anywhere on the aluminum above the ground, you get a small AC voltage reading.

It seems to have a higher reading with thicker aluminum than thin but it is a consistent reading with anywhere from .8 - 1.50 Volts AC.

Aybody know of this and what the source could be?
 
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Do you get a reading on DC ?? Do you get a reading when you put the alumini(u)m and probe into slightly salty water ? I suspect you've re-invented the electric cell...
 
Haven't tried the Salty water but no reading on DC
 
Hello THORPE I had the same thought as Nik but... no reading on D.C? Another thing that springs to mind is that the aluminium rod is acting like an aerial(antenna).The aluminium and its oxide layer at one of the connection points could be acting as a diode and with a meter to complete the circuit you have a simple crystal radio set.Again the problem is that there is no reading on D.C and the voltages you measure seems rather high(perhaps you could try high impedance headphones or a crystal earpiece in place of the meter).Well,I'm stumped but it's an interesting problem.
 
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