Magnetic inductive communication

[ronaldrc]

Has anyone else come across this new communication technique.

For those on here that worry about the magnetic flux or induction coming from a switch leg without a loop or a neutral run with it.

This should really get Karls and a few others in an uproar.

This is a way of using strong magnetic flux to communicate just a few meters.Like your wireless mouse of keyboard Etc.


These will be very low power but so is the flux from a switch leg.

Will this be a hazard?

http://rfdesign.com/mag/radio_magnetic_induction_lowpower/


Ronald

[ December 05, 2004, 09:54 AM: Message edited by: ronaldrc ]

 

[hbiss]

Re: Magnetic inductive communication

I remember seeing that at least 40 years ago, probably in Pop Electronics or one of them. The article showed you how to wind a big flat coil out of magnet wire and put it under your carpet. You then connected it to the output of your hi-fi. Smaller coils enabled amps in the area to pick up the signal without wires.

Don't ask me what they did about the AC hum or the lack of fidelity. :roll:

-Hal

 

[ronaldrc]

Re: Magnetic inductive communication

The technology has been around for the last 75 years just wondered how some feel about it?

A magnetic line of force has a strength to it measured in gauss makes no difference what generated it 120 volt or 1.5 volt.If the gauss generated by the 1.5 volts is as great as the one generated by the 120 volts wouldn't the one generated by the 1.5 volt have the same effect on biological matter as the one generated by the 120 volts?

Ronald

 

[hbiss]

Re: Magnetic inductive communication

Well, no. First they will be using RF frequencies that are magnitudes higher than 60Hz powerline. Second is that the power level will be low.

-Hal

 

[rattus]

Re: Magnetic inductive communication

Not being quite 75, I don't remember, but I expect that they ran audio frequencies through the coil which functioned as a primary. The pickup coils amounted to loosely coupled secondaries.

Remember too, that hi-fidelity was not of prime concern in those days. The gimmick was the thing.

Also, the power and frequencies were so low that no bodily harm would be expected. However, there has been concerned about people living close to super high voltage xmission lines.

[ December 06, 2004, 11:20 PM: Message edited by: rattus ]

 

[jf]

Re: Magnetic inductive communication

Don't get too concerned about this field issue. This is the core of the new WalMart system - some folks know it as RFID - it's the same thing, just a matter of scale.