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help Feedback winding for resonance with pll 4046


Most Helpful Member
I would like to see a radio station prove you are stealing their power in court! A typical judge would tip over back wards in his chair laughing at that one! :D

Radio stations broadcast their signal for free. As far as I know taking some thing that is free is not stealing. Plus AM gets interference and shadowing from odd naturally occurring phenomenon too. ;)
( but yea I have read about stuff like that where a number of times people have done similar things, I know its likely true.)

It would be hard to prove someone was stealing energy from a radio transmitter sense most people that would know anything about radio transmitters would say current RF wave propagation physics dictates its impossible to take energy from a transmitter and have them see it as an additional load.

Some years ago I made a pair of matched Tesla coil type transmitter and receiver units and actually demonstrated a strong and very measurable loading effect on a transmitter power source will taking power off the receiver. :)
Part of that experiment is what I was referring to in the earlier post. The part about by educated accident happening to hit a radio stations frequency and being able to get weak electrical power from it.

I Had two local college electro physics professors grinning from ear to ear for about at week while they played with my power transmitter and receiver set up! :)
By the way the receiver coil sat at a 90 degree angle to the transmitter and used no actual ground or physical connection with the other coil.
It just used pieces of regular aluminum foil for antennas. And it could run a 12 volt 24 watt light bulb at full brightness so it was considered proof that low voltage with a reasonable current could be pulled off of the receiver unit.

They flat out said I proved Tesla's power transmission effect was possible and it in fact defied every physics law they could come up with to properly explain it. :)
Its the only time I have every shown a college professor a home made device that did something out of the ordinary and did not get the deaf ear blind eye treatment. :):(
I don't know if I trust that story so much, sure you can get some energy from RF, but at any appreciable distance the power drops incredibly fast, though I'd love to see someone that can do the math work it out to see if it's possible.

I wish I knew what I know now when I was 15, then I lived less than 1000 feet from every major TV station in Rochester and a huge number of microwave relay towers. Ghosting and reception at my house was impossible because the more receiver was just overwhelmed. With the right antenna array probably could have powered a few small lights =)
tcmtech sorry, but blocking a radio transmitter (by absorbing it's power) is considered interference, direct FCC violation in the states at least. If there are similar laws there the judge would summarily judge against the green house users before there was even a trial. If it were a natural or structural phenominon it'd be understandbly vague, but if the people were doing it intentionally then it'd be illegal. I still don't see how enough power to effectivly heat even a green house could be gotten at any appreciable distance.


Most Helpful Member
True, but given the standard and typical person nowadays cant change spark plugs on their car even, less are going to believe a person is stealing power off of radio station transmitters. ;)

When was the last time you had poor AM reception and thought, Those dam neighbors must have an energy sucking antenna system they are using to run lights or heat there green house with!
I should call the FCC and have them investigated! :eek:

Guess who the community is going to think is a total nutter after that! :D

I bet its not the neighbors.:p
tcmtech just because you don't think it should be illegal or that one can get away (not get caught) with something doesn't make it legal or right. If you're powering a crystal radio then the FCC won't care, if you're powering a greenhouse then you can bet they're going to come knocking. Power companies are on the lookout for dips in the transmission lines too.
tcm, you underestimate human nature =) If the story is true, someone owning a greenhouse or metallic structure noticed that beams of a certain length/configuration where getting warm, where others were not, and figured, hell I'll just build em all like that! They can likely claim ignorance, but a judge would say the offending structures would have to be changed to prevent it from interference from occurring.

There are no 'radio cops', but if you want to see how much people are paying attention set up an RF jammer that interferes with cell phone users in a populated area. They will track you down so fast it'll make your head spin =)
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Most Helpful Member
The legality of stuff is not relevant to the physics behind something.
And right or wrong are very relative to each and every person.
What I may think is wrong you may see as perfectly reasonable and justifiable or vice versa. ;)

Saying the speed limit is 65 mph does not actually prevent a person from being able to drive faster than that.
Saying music and video down loading is illegal does not prevent people from doing it. Its how much and how often you do the items motioned above that gets a person caught! ;)

Pulling a few watts off of local radio stations signals is not likely to ever couse a person any legal hassles. Just dont shoot your mouth off about doing it!
Ask the local drug dealers how they get by.
I bet is not from taking out adds in the Sunday paper!
If you got at good thing going STFU and dont ruin it for yourself! :eek:

If its a neat little experiment share it on a forum! You can shoot your mouth off all you want about the KW's your pulling down from you least favorite music station! :p:)

Post plans, blue prints, spec sheets, and schematics and just go nuts! Those with less moral obligations to the laws they did not vote for or agree to will not have any problem with what you publish!

I posted basic GTI information on this forum and occasionally it still gets the legality of it questioned. But there are far more people that could care less and in fact appreciate the information! ;):)
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Most Helpful Member
I so very want a cell phone jammer that is pocket sized!:)
Just to shut up the idiots that talk on them in places that are not appropriate! ;)

I would bet not one of you have not at least thought that same thing at one time or another! :p:)
The government has them. You could make them. I wouldn't, for the simple fact that if someone near me does something inappropriate with a cell phone it helps me measure them as a person. Even aside from that any such device will effect more legitimate and polite users than it effects the one bad person, the range on a jammer isn't easily controlled.
Thread starter #91
If you use the signal just to create resonance in the circuit and than use the system i want to do maybe could be possible to don't use too much signal. You need only the high voltages to steal the current from the air thats the goal not to absorb the all signal transmitted. It is a starter. Tesla was a genius he would not say oh i discovered a method for transmitting electricity to every one for free, so he didn't told his investors and constructed the all thing. You cant use one device to transmit energy to every one unless it works as i described because if don't people far from the antenna would have no power.


Most Helpful Member
Now your getting it. by tuning the receiver to the radio frequency it will resonate itself up to very high antenna voltages that are needed to trigger the power collection. Thusly you will get a high voltage driver for your collection system without using any power provided by yourself.

Thats where I suspect that static buildup came from I would get.
Simple harmonic resonance. If you calculate how little power there is coming from a radio signal produced over 100 miles away it would be come apparent that there wouldn't be enough energy to do anything useful.

And I would love to see someone from that radio station claim I was stealing their signal power when I was at the outer limit of its transmitter range in the first place!
It's VERY useful for one thing. Communication =)


Most Helpful Member
Thats why if I ever try the experiment again I am going to use the local AM country music station. I could care less if it looses power! :eek::D:p

(Plus the tower is only a few miles from here and it has the strongest local signal)

I sort of wish it was not spring time and I had so much other stuff to do!
I have so many fun and almost educational experiments to try out!:p:)

This would definitely be one of them. Now that I have a lathe winding a very big coil is not a big deal. Last time it took me hours to wind a coil.
Now I could do it in minutes! Plus having a far better idea of what I had happening would make designing and fine tuning far simpler.;)
although dumb luck and shear coincidence gave me some interesting results worthy of a dedicated retest. :)
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Thread starter #96
Useful information about use of 4046 and decade counter for frequency multiplier. and a snap action comparator for pulse shape. here on page 70 71 The Forrest Mims circuit scrapbook - Pesquisa de Livros do Google

I finished the feed back circuit it transform the signal feedback in 50% duty cycle square wave. The center tap is connected to 5v and the opamp lm393 conected to 12v, Rin resistors are 500 Ohm and RF 50Kohm. Voltage of feed back signal is stable and remains the same for any frequency.

I got some strange behavior using 4017 decade counters it didn't seem to multiply the frequency with the pll like 7040 was able to do. don't understand why any help????
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