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How to make a Super Sesitive AM transiver from scratch

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Besides that, the entire purpose of this post is to get help on how to build the thing, not weather or not it works. But thanks for your opinion!
 
Besides that, the entire purpose of this post is to get help on how to build the thing, not weather or not it works. But thanks for your opinion!

How can we give advice on building something that can't possibly work?, but for the frequencies you're talking about check out designs for atomic clock receivers.
 
this has nothing to do with pyramid power. Unless you guys have somthing helpful, as in that will assist me in building the device, to say it would be greatly aprecciated if you would keep your opinions to yourself. Nobody is even being sold anything, nobody is getting ripped off. All this stuff of it working or not is NOT helpful OR appreciated. I don't what to know if ANYONE thinks its possible, I just want to know how to make a reciver that is tuned for the range of 30-60 Khz.
All this UN-HELPFUL advice is EXACTLY why I was NEVER going to tell ANYONE about it, EVEN if it worked. The only reason why I even made one post was to get help on the tank circut, cause everything else that I need I already know enough about. So if your NOT going to tell me how to make the tank circut, kindly keep quiet. I hope I did not offend anyone, I just want to be able to easily find the info I need without having to look through the trash. Thank-you.
 
In case none of you have noticed, at the top of the screen it says, "Electronic Projects Design/Ideas/Reviews Are you building an electronic project or want to? Maybe you need some assistance? Come and submit your electronic questions here and let our experienced members find a solution." not we will determine if it works, even after you have show you obviously don't care if they think it does/doesn't.
 
Are you building an electronic project or want to? Maybe you need some assistance? Come and submit your electronic questions here and let our experienced members find a solution." not we will determine if it works, even after you have show you obviously don't care if they think it does/doesn't.

You are missing the point that people who are very experienced are trying to save you the time and frustration of trying to build a circuit that will not work.
Instead of heading their advice, you reject their advice and state that you know better.
If you ask a question, why reject the expert advice you have received?
 
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I just want to know how to make a reciver that is tuned for the range of 30-60 Khz.
You need to give a better definition of your requirements.
Do you want a receiver which can be tuned between 30 and 60 khz but only demodulates a narrow range of frequencies, typically 5khz.
Or, do you want a reciever which is receiving the whole band from 30 to 60 khz and demodulating the whole lot at once?

Tuned circuits for these frequencies require coils with many turns and can be a pain to wind.

Just recently I built a VLF receiving converter which takes signals in the range 0 to 500khz and converts then to 10.000Mhz to 10.500Mhz so that they can be heard on an existing HF communications receiver.
The converter was simply a 5pole 500khz low pass filter, which fed an SBL-1 double balance mixer. The local oscillator was a single transistor oscillator using a 10.000Mhz crystal for the frequency determining element.
The output of the mixer was fed straight into the antenna socket of the receiver (an Elecraft K2 which is actually and SSB transceiver, but just using the receiver here).

Depending on how you go about picking up the brain signals, you may have problems with off-air signals. You do not state where you are located, but there are some rather high power transmitters on these frequencies which are used by the navy etc for communication with submarines. You may have a few problems keeping those signals out of your receiver.

JimB
 
Assuming you lack much equipment, one way to find resonance is to lightly couple into the parallel resonant tank. Lightly means coupling caps that are less then 50 to 100 times smaller in value then actual resonance cap on tank circuit.

Couple a known frequency source (function generator, etc.) with small cap to tank. Another small coupling cap to voltmeter or scope. Sweep freq and look for peak output.

If you have accurate caps and accurate freq source you can calculate inductance value.
 
You are missing the point that people who are very experienced are trying to save you the time and frustration of trying to build a circuit that will not work.
Instead of heading their advice, you reject their advice and state that you know better.
If you ask a question, why reject the expert advice you have received?

I did not mean to imply that such statements about it not working were not appreciated, they were, but a continuation of such things ARE NOT.

From here on out all posts that do not comtain helpful insights or a request for more info so as to help will be ignored.
 
You might consider using one half of a CMAX time code receiver IC. For example, this one:

**broken link removed**

(download the data sheet for details).

This type of IC has the gain and demodulator that you need, however they assume that you want to receive only one or perhaps three specific frequencies, and so crystal filters are used. If you replace the crystal filter with a tunable filter, you might be able to use this IC for a broad range of frequencies. Beware that the IC gets good sensitivity by recieving a very narrow bandwidth by using a crystal filter. If you don't use a crystal filter, your sensitivity won't be as good as the data sheet says.

One important thing about your project is to realize that the antenna or transducer that you use will be critical to getting good sensitivity. Normally for picking up radio signals at these frequencies, the sensitivity of the reciever isn't all that important because the electrical noise in the environment is so high that your sensitivity is determined by that noise, not by your radio design. If you plan on using electrodes or something like that, make sure that they do not pick up radio signals or radio noise from the environment or you will also suffer a high "noise floor" and poor sensitivity. You could avoid this problem by performing all testing of human subjects inside a faraday cage.
 
You might consider using one half of a CMAX time code receiver IC. For example, this one:

**broken link removed**

(download the data sheet for details).

This type of IC has the gain and demodulator that you need, however they assume that you want to receive only one or perhaps three specific frequencies, and so crystal filters are used. If you replace the crystal filter with a tunable filter, you might be able to use this IC for a broad range of frequencies. Beware that the IC gets good sensitivity by recieving a very narrow bandwidth by using a crystal filter. If you don't use a crystal filter, your sensitivity won't be as good as the data sheet says.

One important thing about your project is to realize that the antenna or transducer that you use will be critical to getting good sensitivity. Normally for picking up radio signals at these frequencies, the sensitivity of the reciever isn't all that important because the electrical noise in the environment is so high that your sensitivity is determined by that noise, not by your radio design. If you plan on using electrodes or something like that, make sure that they do not pick up radio signals or radio noise from the environment or you will also suffer a high "noise floor" and poor sensitivity. You could avoid this problem by performing all testing of human subjects inside a faraday cage.

This is perfect! Thanks, will let you all know how it goes. First I need to get the spending money and time to put it together, may take a while. Will keep checking back for more ideas. Thank-you all for your help!
 
This is perfect! Thanks, will let you all know how it goes. First I need to get the spending money and time to put it together, may take a while. Will keep checking back for more ideas. Thank-you all for your help!

You mean like I suggested in my previous post! - it won't do what you want, but it will receive the frequencies you're asking about.
 
Why do so many gullable people believe the lies from heath Quacks?
They simply steal the gullable people's money.
 
Shuku, My hat's off to you for thinking outside the box in trying to tap in to those forces. I believe too, that everything that has energy, gives off energy and frequencies of some type. As far as trying to give you some advice, I dont have any circuits in mind, but you should read up and or watch the documentary on Dr. Theremin. The Russian scientist that invented the Theremin. This is the musical instrument that was used in many old Sci-fi movies. This instrument sense's the magnetic waves that are given off by the human body and changes it's pitch according to how close you are to the receiver. Kind of reminds you of how an AM radio or the old TV's that used an RF modulator could tune in better if you touched the antenna. Probably due more to ground than anything. But, Dr. Theremin also invented a round table, to play a trick on his wife for her birthday. He sat her birthday cake on the table and when she approached the table, the top of the table would spin. The energy given off by the human body would interact witht the field around the table, either magnet or frequency, not sure. But the top of the table would spin with the cake sitting on it as she got close to it. I got the VHS tape from the local library, and was very interesting. Also, check out the device that ghost hunters use. Called a tri-field meter. It reacts to EMF, Electrical, Magnetics and Frequency.
 
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An AM broadcast-band radio station has a frequency near 1MHz and has an antenna that is very long.
30kHz to 60kHz needs an antenna much longer.
Have you seen anybody with a very long antenna connected to their brain?
A brain does not transmit low frequency radio waves anyway.
What is wrong with gullable weird medical quacks?
 
We had a AM broadcast antenna near my folks home years ago.
That was about 365 feet high - That was 1/4 wave vertical antenna
 
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According to Many text books, anything that uses electricity gives off radio waves. The frequency of the elctricity in the audio centers in the brain and the voltage and ampage all point to the fact that the radio waves that would be given off would be in the 50-55 Khz range, I want to be able to scan outside that range so as to be able to recive any signal, in case my physics proffessors calculations are off. Like I said, I WILL NOT be selling this info to ANYONE, this is for my own personal use ONLY. that being said, NOBODY IS BEING RIPPED OFF!!!!!!!
Besides, if its so impossible, what about this?
YouTube - Mind Control Device Demonstration - Tan Le, these people have already siad it is more that probable, they tried to buy the info I have from me. Like I said, I won't sell it.
 
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