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How to make a Super Sesitive AM transiver from scratch

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I just looked it up.
The brain gives off low frequency electrical signals, not high frequency radio signals.
The EEG picks up very weak signals from 0.5Hz to 70Hz. A typical signal is shown to be 10Hz (Alpha wave).
An ECoG has higher resolution to pick up electrical signals up to about 100Hz which are also not radio signals.
Both machines are connected directly to the scalp with electrodes (not antennae).
 
I guess this person is serious too.
 

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Hey man.

Look, I am ALL FOR the advancement of science, and please DO NOT let skepticism deter you from experimenting. If skeptics had their way, Nikola Tesla would have been put in an insane assylum. Yet he was a genius if not a little eccentric.

But some obvious things that you HAVE to accept. an antenna in the frequency range you desire will be a monstrosity, and will not only pick up theoretical radio waves from a subject brain, but all the 6 billion radio waves being (theoretically) produced around the world. A high S2N ratio indeed! And then, all the solar and cosmic noise to boot. Heck, it would be difficult to seperate the test subject's signal from the testERS. The faraday cage would be great, but putting this enormous antenna inside of it would be quite a challenge :)

Simply put, you are not going to be able to pick up such weak signals, if they do exist, with the antenna that is required...and trying to use a smaller antenna, while not impossible, will only handicap you in orders of magnitude because of the attenuation that is certain to result. Again, you won't be able to seperate the signal from the noise, if the signal isn't so burried beneath the noise as to not be evident!

Think about it, radio experimenters have been monitoring all these radio frequencies for 100 years and have never picked up anything close to "intelligeable" through the noise floor, no patterns outside of natural ones that can be explained.

And supposing you did manufacture a circuit that might detect something, exactly what "language" is the brain speaking in, what modulation type, and why AM?? and why would we think that all brains develop exactly the same pattern so that a device can be used to decipher the waves into some kind of intelligeable language that can be deciphered? Computers are only able to communicate because they are deigned to, and use a predetermined language. Brains have evolved to communicate through spoken language, and thats it. Spoken language is the deciphering tool that allows completely different brain patterns to meet "in the middle" so to speak.

I'm not saying that advancements in technology won't some day unlock some hidden pattern and fine RF in the brain, but I just don't think our technology is anywhere close to this yet.
 
To receive VLF radio waves you do not need a halfwave dipole stretching from here to Timbuctoo!

Consider all the "Radio Controlled Clocks" which receive standard time transmitters on 60 khz (MSF in the UK) or 77.5 khz (DCF77 in Germany, they dont have long dipoles hanging out of the back, just a short ferrite rod antenna (I think the US term is "loopstick") tuned to the appropriate frequency and they work fine.

If I wanted to receive VLF signals from within my head, I would build a multi-turn wire loop antenna, say half a metre in diameter and resonate it at the frequency of interest. Such an antenna could easily go over most peoples heads for maximum signal pick up.

The downside is that it would pick up all the high power VLF transmitters in Europe and beyond.
It would be necessary to run the experiment in a screened room, (Faraday cage) to get a quiet background.

JimB
 
Doesn't Magneto's helmet protect him from psychic attacks.
**broken link removed**

Oh wait he's a comic book charater, you'll have to settle for this.
**broken link removed**
 
Thanks JimB. Yes I do admit that its possible that the whole thing MIGHT not work, but I'm still going to give it all I got before I give up.

P.S. - Nice pics Blueroomelectronics, serously, were do you come up with these pics!
 
My thought was to simply open a cars am radio, replace the inductor with one that would tune it to the proper frequancy range and then hook it up to a series of amps and test in a faraday cage so as to not get as much noise. This is just as a quick and cheep test. What do you guys think, IF it was possible that the brain emits radio waves, would that work?
 
A Radio wave needs a radio transmitter circuit. The brain is not a radio transmitter circuit, it is an electrical low frequency generator.
When it generates 10Hz Alpha waves the amplitude of the waves changes very slowly.

Since brain waves are electrical, not radio, then a conductive path must be made to the skin on the scull. or holes can be drilled in the scull for direct connection to the brain (ECoG).

Radio frequencies have nothing to do with brain waves.
 
My thought was to simply open a cars am radio, replace the inductor with one that would tune it to the proper frequancy range and then hook it up to a series of amps and test in a faraday cage so as to not get as much noise. This is just as a quick and cheep test. What do you guys think, IF it was possible that the brain emits radio waves, would that work?

Most of the AM radios are still superheterodyne architectures. In such a radio it is not so easy to change one or two parts to tune to another frequency. These receivers typically use a 455KHz (or 450 or 460KHz) IF. The RF input circuits are tuned to accept 500KHz to 1750 KHz, followed by a mixer fed by high side local oscillator injection. This local oscillator must be offset from the received frequency by the IF frequency, so the LO is running at 955KHz to 2150KHz. For you to tune down to receive 50KHz to, say, 200KHz or so, you will have to change the local oscillator to tune 500KHz to 655Khz. Then you will have to retune the input circuits to accept 50KHz to 200KHz. Oftentimes, the tuning is ganged so that the input circuits are varied at the same time that the local oscillator is varied. This may be done electronically or mechanically. There is also a chance that the input circuits are broad and fixed-tuned.

I suggest that if you choose to do this, use an AM receiver that you have a schematic for.

Another way to go is to google for "VLF Receiver schematic" or "LF receiver schematic". I did this and got some interesting hits:
**broken link removed**
Build Your own VLF Receiver
S. P. McGreevy BBB-4 Natural VLF Radio Receiver Plans
**broken link removed**
 
You have the strange idea that a brain transmits radio signals.
Now you think a brain has a transmitter power of hundreds of thousands of Watts so that an ordinary AM radio (with its frequency lowered) will receive it??

I don't think so.
 
My thought was to simply open a cars am radio, replace the inductor with one that would tune it to the proper frequancy range and then hook it up to a series of amps and test in a faraday cage so as to not get as much noise. This is just as a quick and cheep test. What do you guys think, IF it was possible that the brain emits radio waves, would that work?

Why are you stuck on AM? What is it about AM that you figure the brain has evolved to replicate? Why not Continuous Wave modulation? That is a much simpler way of imbedding intelligence upon a carrier. AM, after all, is an audio wave transposed upon a higher frequency wave. And if you did detect such intelligence emitted in radio form, where would you start with deciphering it? And what evidence is there that there is anything universal about it that would apply to all brains? In other words, if you "cracked" one human's pattern, it is doubtful that the next person's brain conforms to the same pattern.


I would correct Audioguru on one thing though, a radio transmitter circuit is not required to generate radio waves. The Earth is bombarded with naturally occuring radio frequency energy ever second of every day , produced at the atomic level by reactions in stars, pulsars etc. (I'm not a physicists so I can't describe how, I just know it is there) So just a nitpick, but it isn't by definition impossible for a natural source to generate radio waves without an oscillator and amplifier.
 
I doubt that there are any human brains transmitting radio waves because they are radioactive.
 
Um, the local radio station said they use a 1/2 watt trasmitter, and it goes pretty dang far. The great device that nasa created to send out to space contianing the golden disc for any lifeforms out there to read was at the edge of our galaxy at one point. they said they were going to lose contact with it once in left our galaxy but, they discovered quantum wells, witch even now, they cannot mass produce, they must build them by hand. They detemined that they would be able to recive from the device for another 50+ galaxies, but they would be unable to send to it. Knowing this, you tell me that I cannot build anything strong enough by hand to pick up those small signals, all I needed, like I said before, is how to make the tank circut. Obviously you guys know nothing of electroics, because the basics of electronics teaches that a particale traveling through space creates radio waves. there are many different forms of radio waves, those 'brain waves' you spoke of at .5 Hz to 70 Hz are, in fact, a secific range of radio waves that happen to have a different name then just generic radio waves. So I guess I'll use terminology that you guys will know, I need to know how to build a tank circut that will receive 'brain waves' at 25-45 Khz, now that I've norrowed it down.
some of you may be wondering how I norrowed it down, by using my old am raio tuned to a lower frequancy range, but I can only aproximate its frequancy, so yes in fact it does work.
 
Once my father, who worked on radio for the military big enough for you to stand in that were powerful enough to send a signal back to themselves by going around the world, gets into the state finally I will have the help I seek. Cause I obviously can't get it from you guys, who are supposed to be the "experts" and yet you don't know that a charged particle moving through space creates radio waves. If you don't think that everything emits radio waves, look up the S.Q.U.I.D. (Superconducting Quantum Interferance Device), its sensitive enough to measure fields as low as 5 aT (5×10−18 T) within a few days of averaged measurements. In comparison, a refigerator magnet puts out about 10−2 T. Through extensive research they found everything puts out a magnetic field, witch magnetic fields are low frequency radio waves.

Here is a quote from a physics professor on a online chat room with me:
Radio waves are elctrical and magnetic fields that are osciallting toghther. Depending on the wave length, it can have several dangerous side effects to humans like radiation poisoning. These waves are formed when electrons in a current change speed or Direction. Generally, this occurs through one of two methods. Thermal and Non-Thermal mechanisms. Thermal emission, which depends only on the temperature of the emitting object, includes blackbody radiation, free-free emission in an ionized gas, and spectral line emission. Non-thermal emission, which does not depend on the temperature of the emitting object, includes synchrotron radiation, gyrosynchrotron emission from pulsars, and amplified emission from masers in space.

If you have any more trouble......Google it!
 
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