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98.95.1.119
In Reply to: RE: Do Crystals Work? The Results posted by Maxamillion on April 04, 2011 at 18:21:50
There are multiple problems with your measurement attempt.
1. Use of a basically "shielded" RCA cable, with a tiny amount of "unshielded" center pin at the end, does not a good probe make. Used open circuit (as it appears to be), it MIGHT be capable of picking up gross and overwhelming amounts of E-field, but would also be prone to small amounts of B-field induction, making it a poor probe to check for the presence of E-field shielding.
2. The overall wiring shown in the photo's looks quite chaotic and not cleanly laid out or routed for best results, it is entirely possible that even if the stones had a shielding effect, the excess wiring all over would have allowed the detected spectrum to be picked up anyway.
3. The spectrum analyzer used is basically good for only the audio band. Period.
This is not going to allow pick-up of RF frequency emissions, which is one of the spectrum bands in question.
4. Your spectrum of picked up radiation does NOT look like a prodigious amount of radiation from a switching power supply, in fact, it looks suspiciously clean and missing all kinds of power line harmonics and other switching supply artifacts.
Having measured and dealt with noise and radiation from a variety of switching power supplies, your spectrum analysis results look much more like simple AC power line fundamental and a small handful of weak harmonics, or about what you might pick up from simply being near a line cord, or a simple linear power supply.
Thus, I suspect you are NOT measuring what you think that you are.
5. Your source of crystals is not exactly a golden repository of lab certified gems. They might not even be what they are labeled, or they might be of such a poor grade as to be equivalent to simple gravel in terms of the effects being sought.
It is hard to say what else may have been done poorly in terms of set-up, wiring, measurement, or materials quality, but this is way far off from any sort of definitive or even useful measurement.
Net result: more confusion than confirmation.
Jon Risch
Follow Ups:
"5. Your source of crystals is not exactly a golden repository of lab certified gems. They might not even be what they are labeled, or they might be of such a poor grade as to be equivalent to simple gravel in terms of the effects being sought."
Yep, gravel in your equipment is what gives voices a gravelly sound.
In light of your questions, I repeated the same experiment tonight, but also tested a piece of TI-Shield instead of the bag of crystals. The first plot is the emission from the power supply with no shield, the second is the emission with a piece of TI-Shield between the supply and the probe, and the third is the emission with the TI-Shield grounded with a clip-lead. Once again, the crystals had no noticeable effect, and the plots looked the same as previously posted.
It is clear that the TI-Shield makes a noticeable reduction even in its ungrounded state. Once the shield is grounded, the signal is reduced to almost the level of the background. This control result shows that the system is indeed measuring the shielding effect of whatever is placed between the supply and the probe. It also shows that for the frequencies displayed in the plots, the crystals have no effect, but a known EMI shielding material such as TI-Shield is quite effective.
Based on these results, if you want to shield something from AC electrical fields (frequencies of 50/60Hz plus harmonics) inside your equipment, you are much better off using TI-Shield than using crystals.
SUPPLY EMISSION NO SHIELD:
EMISSION WITH UNGROUNDED TI-SHIELD:
EMISSION WITH GROUNDED TI-SHIELD:
....what you are measuring is primarily magnetic in nature, not E-field so much.
Just as an FYI, a good E-field probe would be an open dipole, that is, two short wires at 180 degrees to each other coming out of a shielded cable at right angles. Thus, the overall appearance would be that of a "T" with the two top portions of the "T" separate and not connected. One side of the top of the "T would be connected to the shield/ground, the other to the center probe. This would ideally be operated into a very high impedance, avoiding any low impedance loading as much as possible.
I suspect that the TrueRTA may have a medium input impedance, rather than a very high one.
BTW, thank you for not taking my comment as an attack, it was just an observation of what you presented initially. Sometimes it is hard to tell just from a text message what the tone is, and it can be hard to convey such nuances.
Jon Risch
....what you are measuring is primarily magnetic in nature, not E-field so much.
How are you coming to that conclusion?
Look at the unshielded plot versus the ungrounded TI shield plot.
Then compare to the ungrounded TI shield plot versus the grounded TI shield plot.
The reduction in the latter is significantly greater than the former.
This tells us that the coupling between the charger and the probe is primarily capacitive in nature, not inductive. In other words, it's primarily E-field.
This makes perfect sense given that his probe is essentially a whip antenna, not a loop antenna.
se
To address the points:
1) The probe obviously picks up radiation when it is near to the power supply. When the power supply is removed, the radiation drops to the background level shown in my first plot. Moving the probe closer to and further from the supply increases and decreases the response. I repeated this experiment with my Tektronix 20Mhz oscilloscope with the oscilloscope probe and saw exactly the same results at a range of frequencies (zero change) - I posted the TrueRTA plots because they were clearer and showed the full spectrum in the audio band in one shot. The crude probe is also quite good at picking up the radiation from the overhead fluorescent lighting above my workbench, so much so that I had to turn them off to avoid interference while I made the measurements.2) Hmmm...the "excess wiring all around" kind of looks like the inside of a piece of audio equipment. I don't know of any gear that has only one wire in it. In any case, almost all of the wires in the picture were diconnected; The two wall warts went to identical battery chargers for my cordless screwdriver, and the other plugged in wire went to my bench receiver located under the bench. The crystals produced ZERO attenuation of the emission from the power supply in the frequency band tested; I'd have expected at least something even if there were other sources of radiation around, as the supply was by far the biggest contributor.
3) I didn't claim to be measuring RF or anything above the audio band - the plots are clearly labeled with the frequency range for all to see. I consider being able to see the range from 20 to 20,000Hz an improvement over the Greenlee meter which has been cited in numerous posts here as definitive proof of an effect. The Greenlee only measures the total emission between 50 and 500Hz, with no hint as to what the individual frequencies of the emission are.
4) Well perhaps the power supply for the cordless screwdriver isn't a switching supply; I just assumed it might be since it is small and many are these days. One thing is for sure, though, the emissions detected were coming from that supply because proximity to the supply clearly affected the amount of emission detected. When I did the same with just the power strip the probe needed to be resting on the opening for the hot in order to register anything significant. Since electric fields fall with the square of the distance from the source, the close-proximity power supply is clearly the dominant source of the emissions detected, especially since almost all of the other wires in the area were disconnected.
5) The source of crystals is just as reliable as the sources being used in all of the posts I see here. Do folks here get certificates of analysis from all the online vendors certifying the identity and composition of the crsytals they sell? In any case, even authenticated crystals, being a natural mineral product, will have a very large variation in composition worldwide; I don't know where I might get a certified reference standard rose quartz or amethyst - even if I could, it would cost a fortune.
Finally, I'd like to say that I have no bone to pick here. I would have loved for the experiment to show a HUGE effect, as I would have then had a new tweak for my system, but alas that was not to be.I appreciate your input, John. Thanks.
Edits: 04/05/11 04/05/11 04/05/11 04/05/11 04/05/11
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