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Author Topic: crystal radio: the first real free energy device  (Read 74264 times)

TinselKoala

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Re: crystal radio: the first real free energy device
« Reply #30 on: February 27, 2015, 06:53:56 AM »
Hi Bill
Here's how I would proceed. You are using a design that will be tuned by the air-variable capacitor, right, rather than by tapping the coil.

So go to the coil calculator site you linked earlier. The old air-variables are usually 365 pF at full capacitance. So plug in 930 kHz and, say, 200 pF into the resonant frequency formula and solve for inductance. I get 147 microHenry for the necessary inductance of the coil.

Now go down to the coil calculator and put in your inductance and the radius of the coil form. I put in 147 uH and 0.625 inch radius, and I went to another website and looked up the diameter of #22 bare wire and got 0.0253 inch. For a closewound coil this is the "pitch".  The calculator returned 114 turns, for 2.88 inches of winding length on the form.

So I'd wrap 120 turns of the #22 wire onto the form. This isn't going to be a very high "Q" coil though. For higher Q consider using a larger diameter form, and re-run the calculation. Make two coils, see which works better for you!

I seem to remember that 300 turns on an oatmeal box form works pretty well for a tap-tuned set with fixed capacitance. You can always sand off the insulation along a 'stripe' of the coil and solder a tap or three on there.

The radio will be influenced by other variables as well, so give yourself plenty of room for experimentation. Plug in other numbers for the capacitor, use the smaller wire, larger diameter form, different frequencies, etc etc.

ETA: The photo below is an old tap-tuned crystal set I made a long time ago. The coil is wound on a plastic 35mm film can. The capacitor is 47 pF. The coil has about 140 turns or so. This set actually works pretty well! It does need a good antenna and ground. I have not tried it with the slinky antenna!

profitis

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Re: crystal radio: the first real free energy device
« Reply #31 on: February 27, 2015, 06:54:51 AM »
Pomodoro:'I just made some homemade synthetic galena, one of a few attempts'

Try doping with various elements including radio-active material.I remember my own series of tests with melted germanium boules,was doping to make it p+ or n-.definitely made a difference on the micro-amp meter

Lakes

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Re: crystal radio: the first real free energy device
« Reply #32 on: February 27, 2015, 09:42:27 AM »
Radio-Active material???

Not generally available I would have thought.

profitis

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Re: crystal radio: the first real free energy device
« Reply #33 on: February 27, 2015, 10:27:21 AM »
Lakes:'Radio-Active material???

Not generally available'

Mr pomodoro plays in the varsity labs

pomodoro

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Re: crystal radio: the first real free energy device
« Reply #34 on: February 27, 2015, 02:41:22 PM »


Try doping with various elements including radio-active material.I remember my own series of tests with melted germanium boules,was doping to make it p+ or n-.definitely made a difference on the micro-amp meter

The whole aim of this is to include a little uranium. I need to melt the galena completely to make sure the uranium dioxide has a chance of dissolving or hopefully reacting with it. 
If it does help to amply the signal, it would need to behave a a true negative resistor, at RF. I cant see the device amplifying in any other way.  In the basic crystal set circuit, with the same load, I should see less loading of the tuning LC circuit, that is, a higher voltage across the LC circuit. That is, if it is a N type negative resistor.  If its an S type I would need to incorporate it in a shunt LC, requiring a coupled coil to the tuning coil.
I haven't been able to find any scientific  literature on semiconductors mixed with radioactive substances as yet.  Surely someone in the 1800s or early 1900s would have tried all of this.
« Last Edit: February 27, 2015, 04:59:40 PM by pomodoro »

profitis

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Re: crystal radio: the first real free energy device
« Reply #35 on: February 27, 2015, 06:03:33 PM »
Pomodoro:'Surely someone in the 1800s or early 1900s would have tried all of this.'

Doesn't mean records are still available today.plenty underground

pomodoro

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Re: crystal radio: the first real free energy device
« Reply #36 on: February 28, 2015, 01:20:23 AM »
Pomodoro:'Surely someone in the 1800s or early 1900s would have tried all of this.'

Doesn't mean records are still available today.plenty underground
Someone would have put their findings in a physics journal to beat other scientists to it.  Also, an amplifying crystal diode would have made big bucks before the advent of the vacuum tube in the mid 20s.

profitis

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Re: crystal radio: the first real free energy device
« Reply #37 on: February 28, 2015, 02:45:10 AM »
Pomodoro:'Someone would have put their findings in a physics journal to beat other scientists to it.'

 better late than never.did you manage to register anything from the doping yet?

Pirate88179

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Re: crystal radio: the first real free energy device
« Reply #38 on: February 28, 2015, 02:54:41 AM »
Hi Bill
Here's how I would proceed. You are using a design that will be tuned by the air-variable capacitor, right, rather than by tapping the coil.

So go to the coil calculator site you linked earlier. The old air-variables are usually 365 pF at full capacitance. So plug in 930 kHz and, say, 200 pF into the resonant frequency formula and solve for inductance. I get 147 microHenry for the necessary inductance of the coil.

Now go down to the coil calculator and put in your inductance and the radius of the coil form. I put in 147 uH and 0.625 inch radius, and I went to another website and looked up the diameter of #22 bare wire and got 0.0253 inch. For a closewound coil this is the "pitch".  The calculator returned 114 turns, for 2.88 inches of winding length on the form.

So I'd wrap 120 turns of the #22 wire onto the form. This isn't going to be a very high "Q" coil though. For higher Q consider using a larger diameter form, and re-run the calculation. Make two coils, see which works better for you!

I seem to remember that 300 turns on an oatmeal box form works pretty well for a tap-tuned set with fixed capacitance. You can always sand off the insulation along a 'stripe' of the coil and solder a tap or three on there.

The radio will be influenced by other variables as well, so give yourself plenty of room for experimentation. Plug in other numbers for the capacitor, use the smaller wire, larger diameter form, different frequencies, etc etc.

ETA: The photo below is an old tap-tuned crystal set I made a long time ago. The coil is wound on a plastic 35mm film can. The capacitor is 47 pF. The coil has about 140 turns or so. This set actually works pretty well! It does need a good antenna and ground. I have not tried it with the slinky antenna!

TK:

Thank you very much for the info.  I did not know that a larger diameter made a difference.  I will do as you suggested...a good starting point.  I should have looked at the value of the variable air cap but, it looks like a "standard' one that can be purchased on some of the radio sites.  (Not those really good ones that are replicas)  I do have a bunch of litz wire salvaged from an old TV yoke.  I may not have enough for a larger coil however.  I was going to use your slinky idea but, I don't have one at the moment and my challenge is to use what is on hand...and have it work well.  (or at least work, ha ha)

Pomodoro:

Thank you for your input as well.  I appreciate it.

@All:

One can purchase uranium from Bob Lazar's site...United Nuclear.  Also, you can salvage Americium from just about any smoke detector.  I do not mess with any of that stuff.

Bill

profitis

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Re: crystal radio: the first real free energy device
« Reply #39 on: February 28, 2015, 03:19:56 AM »
Pirate:'One can purchase uranium from Bob Lazar's site...'

Or from ebay,minerals&gemssection

pomodoro

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Re: crystal radio: the first real free energy device
« Reply #40 on: February 28, 2015, 06:47:52 AM »
Uranium is not dangerous externally - just don't eat it or breathe it in! Same as the americium. Am is like a modern day radium, but you can't get much out of the detector.
Profitis, I have not doped anything as yet. Still getting to know the normal galena first.  The first melt attempt leaked out of a stainless tube at 1250c. The tube had a flat bottom which I thought was an integral part, but obviously wasn't.

Lakes

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Re: crystal radio: the first real free energy device
« Reply #41 on: February 28, 2015, 09:30:55 AM »
At the mention of Radio Active material I was reminded of the boy who built a reactor out of smoke detectors.

http://en.wikipedia.org/wiki/David_Hahn

profitis

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Re: crystal radio: the first real free energy device
« Reply #42 on: February 28, 2015, 11:44:27 AM »
Pomodoro:'Still getting to know the normal galena first.  The first melt attempt leaked out of a stainless tube at 1250c. The tube had a flat bottom which I thought was an integral part, but obviously wasn't.'

Chekout the meltingpoint of PbTe2: 940 celcius.it might also be worth a try.I've made it plenty times by just meting pb and te together until reaction initiates.its same family as galena

pomodoro

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Re: crystal radio: the first real free energy device
« Reply #43 on: February 28, 2015, 01:07:47 PM »
Not sure if I've got tellurium.  I did end up filling the can of a 2n2222a with UO2.  The top of the can is easily 'opened' by filing it away. IThe filing actually files away only at the edges leaving a small disk, which can be replaced back on top after the yellow  powder is put in the can. A bit of glue does the rest. I haven't done any testing of that as yet, apart from measuring the Vbe and Vbc voltage drops, which remained the same.  Using it as a diode in the crystal set was not too good, as expected. It needs to be used as an audio amp as in the Moreland patent. I'm making all the items first and testing them later. 

profitis

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Re: crystal radio: the first real free energy device
« Reply #44 on: February 28, 2015, 03:25:49 PM »
Pomodoro:'I did end up filling the can of a 2n2222a with UO2.'

You may get small effect like this but I doubt it will be registerable.can hardly wait to see actual doping results.doping should theoreticly have orders magnitute greater effect