Electromagnetic interference

[Guest guest]

I just bought one of the cool new QDS Focus amplifiers and have some

questions about electromagnetic interference.

How can I determine if I have too much electromagnetic interference

in my neurofeedback training environment?

Is it possible to train successfully if you do have electromagnetic

interference? Is the impact of electromagnetic interference a matter

of degree or does any interference have a negative impact? In other

words, can you get by with a little bit of it?

I have a Gauss Master and it reports .5 to .8 milligauss in the room

I'm training in. It reports that when its in the position where my

head usually is when I'm training. If I position the gauss meter

closer to my LCD monitor or computer, the reported EMF field strength

gets much higher. Therefore I move a bit away from the electronic

equipment when I train. I've read that .5 milligauss is normal and

is the ambient EMF field.

I created a Bioexplorer design with an oscilloscope and a spectrum

analyzer. The spectrum analyzer is configured to show 0 - 80 Hz with

1024 bins. A big spike exists at 60 Hz. It goes up to about 6u. I

don't see any harmonics though (as far as I know).

Any advice you could give would be appreciated.

[Guest guest]

Hi ,I'm sure there will be some debate on this issue but for many escaping electrical smog is almost impossible.The way I approach the issue is I place a Low Pass filter set at about 55hz between my oscilloscope and the source object. If you don't use an impedance meter the scope offers a chance to see that your hook up is reasonably good.The spectrum analyzer I usually set at around 45hz. That will eliminate the 60hz interference.For training you are using filters that are below 60hz anyway. Like I said there will probably be some debate on this issue and the truth is that in a perfect location we could escape the electrical smog. 60hz is the one we see the most but there are many higher frequencies all around that we don't detect because we don't have filters high enough to catch them.Larry Chambers wrote: I just bought one of the cool new QDS Focus amplifiers and have some questions about electromagnetic interference. How can I determine if I have too much electromagnetic interference in my neurofeedback training environment? Is it possible to train successfully if you do have electromagnetic interference? Is the impact of electromagnetic interference a matter of degree or does any interference have a negative impact? In other words, can you get by with a little bit of it? I have a Gauss Master and it reports .5 to .8 milligauss in the room I'm training in. It reports that when its in the

position where my head usually is when I'm training. If I position the gauss meter closer to my LCD monitor or computer, the reported EMF field strength gets much higher. Therefore I move a bit away from the electronic equipment when I train. I've read that .5 milligauss is normal and is the ambient EMF field. I created a Bioexplorer design with an oscilloscope and a spectrum analyzer. The spectrum analyzer is configured to show 0 - 80 Hz with 1024 bins. A big spike exists at 60 Hz. It goes up to about 6u. I don't see any harmonics though (as far as I know). Any advice you could give would be appreciated.

Never miss a thing. Make Yahoo your homepage.

[Guest guest]

Thank you Larry.

I forgot to mention that I do have an impedance meter and my impedance

is always less than 5K. If its greater than 5K, I redo my prep until I

get less than 5K.

When I train, I hold my amplifier in my lap and have a long RS-232

cable from the amplifier to the computer so I can sit away from any

other electronic devices. The electrode cables do not cross any power

cables and are at least two to three feet from any electronic devices.

[Guest guest]

,It sounds like you have everything under control. And you are using a QDS amp. One thing I didn't mention about electrical smog is that the 60hz stuff comes from electrical outlets and wires that run through the place where you train. Either home or office. So as you can see it is very difficult to get completely away from it.Larry Chambers wrote: Thank you Larry. I forgot to mention that I do have an impedance meter and my impedance is always less than 5K. If its greater than 5K, I redo my prep until I

get less than 5K. When I train, I hold my amplifier in my lap and have a long RS-232 cable from the amplifier to the computer so I can sit away from any other electronic devices. The electrode cables do not cross any power cables and are at least two to three feet from any electronic devices.

Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.

[Guest guest]

,It sounds like you have everything under control. And you are using a QDS amp. One thing I didn't mention about electrical smog is that the 60hz stuff comes from electrical outlets and wires that run through the place where you train. Either home or office. So as you can see it is very difficult to get completely away from it.Larry Chambers wrote: Thank you Larry. I forgot to mention that I do have an impedance meter and my impedance is always less than 5K. If its greater than 5K, I redo my prep until I

get less than 5K. When I train, I hold my amplifier in my lap and have a long RS-232 cable from the amplifier to the computer so I can sit away from any other electronic devices. The electrode cables do not cross any power cables and are at least two to three feet from any electronic devices.

Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.