Designing a Variable Directed EMF Generator: Difficulty and Schematics

[Vladdek]

I'm relatively new here, but I felt that you guys might be able to help me.
I'm trying to design a directed electromagnetic field generator with a variable field strength and oscillation rate.

What I'd really like to know is exactly how difficult would this be?
My EE experience is rather minimal because I'm mostly an experimenter, but I'm trying to get into a nice college to get a BS in EE, that's unrelated though, except to give you a kind of general view into my level of expertise.
Secondary to my first question, would anyone be able to draw up a schematic or maybe show me to a place that has one?
I don't really want to go into details on what this is for, but I'm thinking about a noninvasive method to produce a strong magnetic field using the constructive interference between two weaker directed emf generators. I haven't been able to find anything on my own, which is one of the reason I'm asking you guys.
I really feel like a "newb" asking here, but you're my last bastion of hope!

Much appreciation and respect,
Vladdek

 

[berkeman]

I'm relatively new here, but I felt that you guys might be able to help me.
I'm trying to design a directed electromagnetic field generator with a variable field strength and oscillation rate.

What I'd really like to know is exactly how difficult would this be?
My EE experience is rather minimal because I'm mostly an experimenter, but I'm trying to get into a nice college to get a BS in EE, that's unrelated though, except to give you a kind of general view into my level of expertise.
Secondary to my first question, would anyone be able to draw up a schematic or maybe show me to a place that has one?
I don't really want to go into details on what this is for, but I'm thinking about a noninvasive method to produce a strong magnetic field using the constructive interference between two weaker directed emf generators. I haven't been able to find anything on my own, which is one of the reason I'm asking you guys.
I really feel like a "newb" asking here, but you're my last bastion of hope!

Much appreciation and respect,
Vladdek

Welcome to the PF. What frequencies are you considering? A directed EMF generator sounds like a RF signal source and an antenna of some sort -- is that what you mean? Or are the frequencies you are considering down low, where a resonant antenna arrangement would not be practical?

 

[Vladdek]

Welcome to the PF. What frequencies are you considering? A directed EMF generator sounds like a RF signal source and an antenna of some sort -- is that what you mean? Or are the frequencies you are considering down low, where a resonant antenna arrangement would not be practical?

Thank you :D

I was originally thinking about a RF transmitter that broadcast a certain dB of tone on a frequency determined by the output of an audio card, but I wasn't sure if that would work. Originally I was hoping to see a range of 1hz to 10khz, but maybe 1khz to 10khz would be more realistic? If the constraint is something like an antenna size, efficiency is less important, because I can compensate with a higher power.
Just to be clear, because all the people I've talked to haven't quite understood the first time, the objective is not to broadcast a sound output (like music) over a specific frequency (like a radio transmitter for your iPod or similar) but rather to broadcast energy/radiation in the form of MF/EMF at a frequency and power that can be altered. I thought about this and it seemed to be that I could simplify a RF Transmitter circuit in some way to achieve this. I hope this helps some.
Again, respect and appreciation,
Vladdek

 

[berkeman]

Thank you :D

I was originally thinking about a RF transmitter that broadcast a certain dB of tone on a frequency determined by the output of an audio card, but I wasn't sure if that would work. Originally I was hoping to see a range of 1hz to 10khz, but maybe 1khz to 10khz would be more realistic? If the constraint is something like an antenna size, efficiency is less important, because I can compensate with a higher power.
Just to be clear, because all the people I've talked to haven't quite understood the first time, the objective is not to broadcast a sound output (like music) over a specific frequency (like a radio transmitter for your iPod or similar) but rather to broadcast energy/radiation in the form of MF/EMF at a frequency and power that can be altered. I thought about this and it seemed to be that I could simplify a RF Transmitter circuit in some way to achieve this. I hope this helps some.
Again, respect and appreciation,
Vladdek

Frequencies up to 10kHz aren't really RF, and it's hard to launch an EM wave at those frequencies. Are you thinking more of a local resonant coil to transfer energy locally for some reason?

 

[Vladdek]

Frequencies up to 10kHz aren't really RF, and it's hard to launch an EM wave at those frequencies. Are you thinking more of a local resonant coil to transfer energy locally for some reason?

I had to look up a resonant coil on Wikipedia :D I found a 'Resonant energy transfer'. If that's the same thing, I don't believe it'll work. I think I'll try to explain the purpose of the device and hopefully you can help, I do appreciate the effort you're making.
Basically, I'm interested in what I could only really describe as EM Neuro stimulation. I'm going off some studies I've found and the relative harmlessness of EMF on the brain. (and as the test subject, I'm not going to burn out my brain :) ) Some older studies have shown an appreciable benefit in neural activity in specific areas that are exposed to an oscillating magnetic field and more recent ones have shown an appreciable improvement with direct electric stimulation (of a very low wattage). I'm more interested in the former. It sounds a little wacky, I know, but I trust the studies and I'm quite interested in it. Thus, I need to direct an oscillating magnetic field at a relatively small region (say 1-2 sq in). I was going to further minimize any potential risk by using two of these generators and constructive interference to apply the most energy to a specific area while leaving the other areas relatively unaffected.

I hope this doesn't sound too 'new age-y' to continue to garner your help, it's completely backed by science.

Respect,
Vladdek

 

[berkeman]

I had to look up a resonant coil on Wikipedia :D I found a 'Resonant energy transfer'. If that's the same thing, I don't believe it'll work. I think I'll try to explain the purpose of the device and hopefully you can help, I do appreciate the effort you're making.
Basically, I'm interested in what I could only really describe as EM Neuro stimulation. I'm going off some studies I've found and the relative harmlessness of EMF on the brain. (and as the test subject, I'm not going to burn out my brain :) ) Some older studies have shown an appreciable benefit in neural activity in specific areas that are exposed to an oscillating magnetic field and more recent ones have shown an appreciable improvement with direct electric stimulation (of a very low wattage). I'm more interested in the former. It sounds a little wacky, I know, but I trust the studies and I'm quite interested in it. Thus, I need to direct an oscillating magnetic field at a relatively small region (say 1-2 sq in). I was going to further minimize any potential risk by using two of these generators and constructive interference to apply the most energy to a specific area while leaving the other areas relatively unaffected.

I hope this doesn't sound too 'new age-y' to continue to garner your help, it's completely backed by science.

Respect,
Vladdek

I don't think we can help you with making a machine to experiment with the effects of high fields on your brain (sorry, against the PF Rules). But I can point you to some really interesting research that's going on now at Stanford and other places. Might be of interest to you:

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

Stanford group: http://www.stanford.edu/group/dlab/optogenetics/ (click on "nature protocols for a paper)

.

 

[Vladdek]

Regrettable, but I understand. I guess I should have taken more time to look over the rules than I did. I had some other uses for this as well, but now it will all be taken in the context of my previous query. I still appreciate your time, I learned a few things that will make my future searching more easy because it'll be more specific.

Hopefully now that I've learned of this place, I'll talk to you and others about fun and interesting physics related stuff. :D Once again, I appreciate your time, you've been nothing but helpful and direct.