Could this be characterized as a transistor?

[RobMcN]

I began experimenting with a technology from the 1890's which generated power for the early telegraph system (see https://en.wikipedia.org/wiki/Earth_battery) thinking that with the availability of newer materials such as graphite and with todays tech I might be able to find a way to make this more viable. I've succeeded in making this viable but it is extremely difficult to characterize an 'Earth Battery' cell as a battery cell - the numbers simply are non-linear.

However, consider a few things and tell me if this could actually be a transistor. Let's take a bin of soil that is mostly made up old compost - very heavy in clay, which after doing some research I came to realize contains not only a mix of heavy metals but a lot of silicone. Into this bin we place an 8"x8"x.090" plate of Magnesium (AZ31B - 96% Mg, 3% Zn, 1% Other) and at the other end of the bin a 4"x4"x.090" plate of pure Graphite.

If this were a battery cell, the Carbon has a potential difference of 2.3 V compared to the Mg when in an electrolyte. Because of pH differences, moisture difference, etc, we only get 1.3V and we look for a source resistance by shorting the cathode with the anode and looking for the instant current and we also take various measurements with resistors and we've done this on Electronics Engineering Stack Exchange with results that don't make sense. Lots of reasons are given why these numbers don't make sense. However, I modeled a pnp transistor on Ltspice because of a suspicion I had and was able to get some of the results.

Here's the theory:

We have Carbon, which is a Group IV element, so in silicon that would make it a p-type material, heavily doped because it fouls in soil. Then we have the Mg which is a Group II element in silicon which is also a p-type element and is doped by the oxidation process (the other heavy metals in the surrounding clay embed themselves into the Mg as it corrodes, I've witnessed this.

Now we have a PNP transistor with the Emitter being the Carbon, the Base being the Soil and the Collector being the Mg. Also, because the soil is moist, creating an electrolyte, it allows electrons to flow.

Second, when I do resistor tests over time (over 24 hour periods) I see rises and falls in the current around sunset and sunrise - proving the telluric current concept spoken of in Wikipedia. That would be something more familiar to the base of a transistor than to a battery, wouldn't it?

Also, Here are some of the tests I performed when trying to characterize it as a battery:

1. Shorting the device and reading the current. Using the ammeter setting on my multimeter which has separate settings for μA, mA, and A. Set to μA. Positive lead attached to Cathode, Negative Lead to Anode.

Result: 0.00 (possibly not sensitive enough?)

1. Finding the Open Voltage. Using the Voltage Setting with the multimeter still attached as in step 1 but leads are separated so as not to touch.

Result: 1.327 and slowly rising [over an hour this will rise to 1.68]

1. Attach various resistances and measure voltage. Voltage setting with multimeter still attached as above. The resistor is measured first separately, then placed in between the multimeter leads. (Voltage shorted to 1.327V prior to each test) Resistors are Carbon film except in the one instance mentioned. The voltage source has an unstable frequency measured on an oscilloscope between 2Hz and 10Hz

Results:

• 2.3 ohms, 1.4mV
• 5.1 ohms, 6.7mV
• 21.9 ohms, 14.5mV
• 99.5 ohms, 127mV rises at rate of 2mv/s. (127mV is initial reading)
• 150.9 ohms (wirewound resistor), 182mV*
• 325.8 ohms, 347mV rising

*The 150.9 resistor started out at 110mV and rose at a rate of approx. 0.5mV/s for over 7mins, at which point I took the 182mV reading and stopped. While I recorded the readings and looked up, it had already reached into 188mV's and still was rising.

1. Using the Diode setting (to see how it would charge). (leads attached in the same fashion)

Result: 1.715 rising rapidly to 2.0 at which point my multimeter went to O/L. I quickly went to μA setting and shorted the leads. still 0μA

Back at Voltage Setting.

Result: now at around 1.71V and slowly dropping until it reaches 1.35V over twenty seconds

1. Use Diode setting to 'recharge' to 2.0V. Return to Voltage Setting and Short

Result: Immediate discharge from 1.98V to 1.35V

1. Capacitance Setting

Result: Multimeter read 0.000 [indicating seeking] then eventually O/L [Too large] Max 2mF for this multimeter.

And that made me think of the Pi model for a transistor:

And I'm still trying to develop an Ltspice model that will work, but this is what I have for now:

I would love to hear an expert opinion of a what a Group IV Group II PNP transistor model would act like! And if this would qualify.

Robert

 

[U235]

One thing I would say -- and it might help is:

If you take a PNP transistor, and measure the open circuit voltage (with a voltmeter) between any and every contact you will see: 0V. (same as with a PN-junction diode)

If you connect the terminals of a PNP transistor together -- either shorted or through resistors -- you will see zero current flow. 0 uA

Your earth-battery arrangement/ prototype does not look like a PNP transistor.

Keep going though!

I'd focus on the battery aspect. A battery, and diode or transistor are very different.

 

[RobMcN]

One thing I would say -- and it might help is:

If you take a PNP transistor, and measure the open circuit voltage (with a voltmeter) between any and every contact you will see: 0V. (same as with a PN-junction diode)

If you connect the terminals of a PNP transistor together -- either shorted or through resistors -- you will see zero current flow. 0 uA

Your earth-battery arrangement/ prototype does not look like a PNP transistor.

Keep going though!

I'd focus on the battery aspect. A battery, and diode or transistor are very different.

First, let me say that I am pursuing the battery cell aspect on Stack exchange and trying to characterize it as such. But because the results are anything but normal I want to just theorize down this road a little longer. Will you, or whoever else joins this conversation, try to theorize a bit longer?

Let's say however, that this PNP transistor is attached to a circuit, already, in a way.

We know telluric current exists - that was confirmed through the telegraph system in the late 1800's and is used for sourcing minerals today. It has an unstable frequency of around 5Hz and rises and falls around sunset and sunrise. My observations are shown in this graph which show the voltage around one hour peri-sunset. So, it appears it is affected by an external source or 'circuit' in some way.

I theorize that these particular Group II and Group IV elements are not normally used in transistor creation because they are electrodes with volts vs SHE of high potential, in this case, the highest potential among all the most/least noble elements. I imagine you don't normally want a transistor to have its own voltage potential compared to ground, which is why the materials are called "semi"-conductors. I am trying to proof my answers with research as I write this, but I can't seem to find the electric potential of SiGe (Silicon Germanium used in most p-junctions) except that it is a semiconductor.

Yes, you are correct. In a transistor, you attach any two terminals and get 0 volts. Can you imagine with me a little further?

Attach the Emitter terminal to an 'antenna' of sorts that can collect telluric currents; this happens to be at a potential of 2.3 volts. Attach the base to the literal earth ground and call that 0 volts. Then attach the collector to the ground of that antenna which happens to be -0.2 volts. As for the 'current' of those potentials - that depends on how big your antenna is and how its attached to your transistor.

Your part in this discussion, though, has helped me define some questions.

Has a Group II, Group IV transistor ever been built and if so, what were it's properties? If it's not ever been built, has anyone theorized on its properties?
Buts here's the big question:

If this were a transistor, then we should be able to place it in a circuit and have it act like one, in ways that a battery definitely would not act. Keeping in mind, however, that it will have its own electric potential. And that is what I need help with from semiconductor experts - as I am not.

Robert

 

[U235]

Hi Rob

In reference to the above:

"I imagine you don't normally want a transistor to have its own voltage potential compared to ground, which is why the materials are called "semi"-conductors."

This is incorrect.

"We have Carbon, which is a Group IV element, so in silicon that would make it a p-type material"

This is incorrect. Carbon doped Silicon is an intrinsic semiconductor -- neither n nor p-type.

"... but I can't seem to find the electric potential of SiGe (Silicon Germanium used in most p-junctions) except that it is a semiconductor."

This doesn't make sense, to be honest. SiGe is a semiconductor alloy, and it's used in a number of applications. The electric potential of a SiGe region/material lump could be anything, depending on the circumstances. i.e. what it's connected too. You also need to be careful of the subtleties of electric potential vs the electro-chemical potential (fermi level) in semiconductor devices.

Proper Mg doped silicon would be a double donor (I think). So, it'd be n-type. It's not a common thing to do, however.

This is not an attack on your work: subjects like semiconductor and solid state physics aren't straight forward. They need a significant amount of study. Simply speculating, guessing, or theorizing how semiconductor devices work will mislead you.

IMO: you cannot make a transistor in the way you suggest.

Good luck with your work.

 

[RobMcN]

Hi Rob

In reference to the above:

"I imagine you don't normally want a transistor to have its own voltage potential compared to ground, which is why the materials are called "semi"-conductors."

This is incorrect.

"We have Carbon, which is a Group IV element, so in silicon that would make it a p-type material"

This is incorrect. Carbon doped Silicon is an intrinsic semiconductor -- neither n nor p-type.

"... but I can't seem to find the electric potential of SiGe (Silicon Germanium used in most p-junctions) except that it is a semiconductor."

This doesn't make sense, to be honest. SiGe is a semiconductor alloy, and it's used in a number of applications. The electric potential of a SiGe region/material lump could be anything, depending on the circumstances. i.e. what it's connected too. You also need to be careful of the subtleties of electric potential vs the electro-chemical potential (fermi level) in semiconductor devices.

Proper Mg doped silicon would be a double donor (I think). So, it'd be n-type. It's not a common thing to do, however.

This is not an attack on your work: subjects like semiconductor and solid state physics aren't straight forward. They need a significant amount of study. Simply speculating, guessing, or theorizing how semiconductor devices work will mislead you.

IMO: you cannot make a transistor in the way you suggest.

Good luck with your work.

Thank you so much!

I took none of that as an attack, but a boost to my knowledge. I have little knowledge of semiconductors, which is why I'm reaching out to the community that does. Lots of great points here.

Never heard of an intrinsic semiconductor before and did a bit of extra reading already. Thank you for that. And for pointing out the difference between fermi level and electric potential. I had noticed that in other posts, but without explanation. You didn't explain the difference either, but you at least showed where the difference lies which helps me understand better.

What this has done, is helped to dissuade me from the transistor theory and put more effort into the earth battery cell characterization. In that, I consider your answer to be complete and the subject closed. However, if you felt like expanding my knowledge in some of those points above or pointing me to some good reads, I would be grateful. I love knowledge and inventing.

Kind Regards,
Robert