From: Jim Meissner (jpmeissner_at_mindspring.com)
Date: 2002-02-12 00:31:56
Dear Andreas:
Some information for you.
The Mind Mirror uses a fairly large 12 volt gel cell. I think it is a 2 Amp hour size ( 6 x 2 x .5 inches ?). Internally there are several power supplies. A 78LO5A provides +5 volts for the logic. A Negative Rail Generator generates the - 12 volts. Some inverters drive discrete switching transistors into a voltage doubler. Also two discrete "stabilizers" provide + and - regulated 5 volts for the analog.
I will give you some examples of what I tried for power supplies.
The Hal-4 uses three batteries. One for + 6 volts, one for - 6 volts and a9 volt for the isolated RS232. The + 6 volt batteries would go dead sooner because that also ran the microprocessor. I found a small DC/DC that putout +/- 5 volts with a 3 to 5 volt input. I replaced both +/- batteries with one set of NiCads that could be recharged. I left the 9 volt battery alone since it lasted a long time and needed to be well isolated. That has proved to work well.
For my baseball cap EEG with the RF interface, I used rail to rail op amps and 4 x 1.5 volt AA alkaline batteries for the + 3 volt and - 3 volt. The RF section used + 3 volt and had it's own internal regulator and used very little power. This system ran for days without battery replacement.
The latest version of my brain wave monitor went through many power supply trials. The heart is the HC11 and I used the same power supply scheme I use for my Brain State Synchronizer. This uses 6 AA rechargeable Nicads followed by a low dropout TO-92 regulator to give the + 5 volts for the microprocessor. This gives about 5 hours of battery life. The analog power supply voltage is + 5 volts and - 3 volts. The minus voltage is generated by a7660 chip that converts the + 5 to - 5 volts and switching losses to give a sloppy -3 volts ( no regulation ). This worked well enough for quite some time. Eventually I added a + 5 volt to "isolated" +/- 12 volt DC/DC converter for the input stages. Having more "headroom" allowed the input to accommodate higher common voltage input voltages and perform better after an overload. When I added the biofeedback package into the same carrying case and sharing the power supplies I began to have major feedback problems. The "isolated" DC/DC helped reduce this feedback. The combined brain wave monitor and biofeedback are packaged in a standard size attaché case and can be used without a computer hookup. The biofeedback package consists ofa power amplifier to drive a pair of 6.5 inch subwoofers to full compliance. This requires a lot of power and I chose to use a single 12 volt battery consisting of a string of C size Nicad batteries. There is an external connection for a higher power ( 7 AH ) 12 volt gel cell. This portable system can be used where there are no power lines and less than 60 Hz interference.
I will briefly describe the biofeedback scheme. I hope that the information will be useful to the group. I expect to get flamed by Doug Sutherland again, but others may find this interesting. There are two main areas wherelistening to your brain can provide real time feedback.
Relaxation: Transitioning out of the Beta State towards an Alpha or lower state. Initially what you will hear is a lot of white noise generated by the brain's random firing in the Beta state. You will not hear a tone or any coherent repeating brain frequencies. If you have learned how to relax "somehow" by some method, you will hear the higher frequencies reduce in amplitude and eventually all the frequencies begin to get more quiet. I am still speaking of random frequencies here. If you can remain in this quiet state for 5 or 10 minutes, eventually all the Beta random mind activity stops. On the EEG you would see all the FFT bins to be empty. BUT, once you realize that you have achieved something, your mind instantly goes back intohyperactivity celebrating, and you have to start all over again. It takessome time to be aware of your progress with one part of your mind without reengaging the Beta state. Traditionally this takes years and years of practice. This type of biofeedback helps because it immediately lets you knowthat you "lost it", and you can try again. If you do this ( the suppression of Beta activity ) successfully, there comes a time that, for some people, not all, you may enter the Alpha state. On the EEG, the FFT will show a coherent very steady 9.5 to 10 Hz signal. I have found that everyone I have tested has the same Alpha frequency within the accuracy of my equipment. ( I still do not know why, where is the sync signal? ). If you look at this with my waterfall display FFT, you will see a picket fence of 10 Hz datagoing back through time. The amplitude of this signal can be quite large in a few people. In some others it will be low amplitude and sometimes sporadic. Others have none at all. I have not found any correlation between Alpha amplitude and anything. It certainly does not represent the relaxed state as is touted by all biofeedback protocols for Alpha training. I have recorded no Alpha in very relaxed people, and large amplitude Alpha in someone in a hyperactive frenzied state. I have developed a protocol for improving the Alpha state and even teaching people to produce Alpha with open eyes. The method involves lightly putting your fingertips on the sub woofer speaker cone. Even though you cannot hear the 10 Hz signal, it is very obvious to the touch. You can try different things to start the 10 Hz signal.In my case if I blink or momentarily shut my eyes tightly, I will generate some high amplitude Alpha 10 Hz signals. Even though I spent some intense time practicing, I found no benefit for the effort. When I realized thatI had talents and skills far beyond those with "good" Alpha waves, I stopped and wrote it off as another New Age hype. ( I am able to drop my respiration rate from an average of 12 breaths a minute to as low as 2 breaths a minute and as high as 34 breaths a minute. Not many people can do this, soI think it is much more meaningful than Alpha waves! ) But, I am sure Doug will find thousands of references on the internet proving I am wrong! That does not intimidate me from attempting to share my experiences, all of which can be verified by building a "buildcheapeeg" brain monitor. Coming soon?
Energize Up mode: This is the second way that the biofeedback speakers canbe used. There is some very interesting activity at the 40 Hz brain wave frequency area. This seems not to be explored by many people and most of the brain wave monitors do not go high enough to cover this range of frequencies. If you listen to your brain and instead of decreasing the amplitude of the white noise of the Beta state to relax, you do the opposite. Try toincrease the amplitude and the frequency spectrum of the random brain wavefrequencies. This will not be as easy as it sounds and "may" require several weeks of training with the Brain State Synchronizer. Once you develop the mental muscles to increase the brain state, here is what you will see on the EEG FFT. Initially most people will have a frequency spectrum that may go as high as 15-20 Hz before the amplitude begins to drop. Let me emphasize again, there are no steady or coherent frequencies here. This is thewhite noise of neurons firing at random. As you learn to flex the mental muscles or rev up your engine, the top frequencies will increase as will the amplitude. It will sound like a thousand jackhammers going at once. As you watch the EEG or listen to the amplitude you will find that you cannot keep it up for very long before you get real tired. Think of it as weight lifting with your mind. Eventually you will be able to put your mind in high gear. You will have reached your goal when you can produce 40 Hz frequencies at will. On the EEG FFT you will actually see a peak amplitude centered around 40 Hz that may be twice as high as the 20 Hz frequencies. AgainI am not saying you will see a coherent or steady 40 Hz single frequency. It is just that the random signals around the 40 Hz region will be twice as loud or higher in amplitude. Once you can achieve this state magic things happen. All the things promised by the EEG/NF protocols actually come true. I will do a tiny brag about what I have been able to achieve ( read the website for more hints ). Using the Synchronizer and the EEG FFT to verify function, I have been able to change my life in many positive ways. Themost important thing to me at the time was improving my tennis game. Withthis training I was able to slow down the speed of the tennis ball and move from the worst player to first place trophies. I actually became a certified tennis pro and taught tennis for 10 years, believe it or not. I can now speed read and accomplish 2 or 3 times more than before using the higherbrain states. I also developed the ability to do hands on healing and have made the lame to walk again without needing an operation. A few years ago very few believed in this, but more and more of the population is becoming "aware". Jesus said whatever I can do you can do also! But you still have to do the work and train. I have worked with many learning disabled children. One "autistic" kid who was being dropped back a grade for not beingable to keep up with the class, scored a 92% in reading and comprehension after 6 weeks of training time. Dealing with the "hyper" kids is more complicated but quite successful.
Let me challenge the EEG/NF misconception that is prevalent in the New Age circles. Believe it or not, sound frequencies played to the ears, either direct frequencies or binaural beats, light flashing frequencies in the eyes, CES or electrical pulsed frequencies to the brain, do not show up as brain wave frequencies on the EEG FFT display. Entrainment by that definition does not work, neither can the frequency following response be verified! There are no good or bad frequencies even though there are many lists describing all sorts of magic frequencies.
( test it your self with your new buildcheapeeg machine ) Coming soon?
This does not say I don't believe in EEG/NF, but it does not work as promised. My Brain State Synchronizer uses direct sounds and binaural beats and produces great results, but is not an entrainment process using magic frequencies. It is a training tool.
( The following must not be construed as a negative comment about Jim Peters or Joerg! )
Jim Peters is spending a lot of time attempting to build the perfect filterto find these elusive brain waves that he believes "must" be there. I have read some correspondence between Jim and Joerg on the EEGS group where they were running these tests. Joerg noticed that the binaural beat frequencies of Jim's brain wave generator were NOT showing up on the EEG FFT even though he tried numerous frequencies from .5 Hz to 50 hz. ( This is what I have been saying all along and nobody is listening! ) Joerg "wrongly" assumed that this must be a "weak" interaction and one must look harder with better filters. How could Monroe Institute be wrong? Well, guess what? Their tapes really work and take "some" people to interesting out of body destinations. Their Hemi Sync brochure is written by the advertising agency. It sells a lot of tapes. They seldom use the EEG machine that they have. If you specifically request it, they will charge $150 to do one session with you. There is a discontent locally that it is not used more for research.
I really wish that Jim Peters would focus his great software talent on building the software instead of duplicating Andreas efforts on the input stage. We need some good software to show what the EEG FFT really looks like. Displaying it as a voice print such as Spectra Plus does, would also look great. BTW Jim, I have lots of real brain waves already recorded to study.
Well, I hope someone gets some benefit from this rather long monolog.
Juergen P. (Jim) Meissner
Check out my Website at www.MeissnerResearch.com
Read about the benefits of the Brain State Synchronizer sounds for improving your life and health.
----- Original Message -----
From: sleeper75se
To: buildcheapeeg_at_yahoogroups.com
Sent: Monday, February 11, 2002 9:29 AM
Subject: [buildcheapeeg] Loose ends: Power
Hi all,
I'm looking into the last part of my project: power.
What do you think about this solution, going from input to output:
2x1.5V batteries is connected to a
-> step-up DC/DC converter (MAX857)
It generates 6V from input voltages as low as 0.8V.
-> post filtering (lowpass) using a passive LRC combination to get
rid of some of the ripple (300kHz)
L=100uF, R = 2 ohms, C = 100uF + 10uF attenuates 300kHz about 90dB.
That should be more than enough. :-)
-> low-dropout 5V regulator (LT1761, 20uV rms widband (<100kHz)
noise) and a big low-ESR 100uF capcitor for stability.
Since I need +/-5V I want to build two identical sections and connect
them in series, with ground in the center. A voltage inverter and a
negative LDO-regulator might sound better, but I'm having trouble
finding a good LDO-regulator for negative voltages.
Are there any potential problems with this approach?
Joerg, Jim M, what do you think?
/Andreas
Yahoo! Groups Sponsor
ADVERTISEMENT
To unsubscribe from this group, send an email to:
buildcheapeeg-unsubscribe_at_egroups.com
Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
This archive was generated by hypermail 2.1.4 : 2002-07-27 12:28:38 BST