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From: Michael A. Terrell on 26 May 2010 20:34

David Nebenzahl wrote:
>
> On 5/24/2010 10:06 PM Jeff Liebermann spake thus:
>
> > Adding more topic drift, I had a customer that claimed that she could
> > "feel" the radiation coming from her new computah. I did a single
> > blind experiment to see if she could tell if it was turned on and
> > found that she really could. I had no clue, so I walked down the
> > road, injested an ice cream (favorite brain booster), and did some
> > thinking. I used an ultrasonic pipe leak detector to find that the
> > desktop power supply was belching considerable audible ultrasonic
> > noise. I tested every PC power supply I had in stock, found the least
> > disgusting, and replaced her power supply. She claimed she could
> > still "feel" it, but that it was much better. I eventually buried the
> > xformers and inductors in RTV, which solved the noise problem. She
> > was one of the rare adults that did not lose their childhood high
> > frequency hearing.
>
> In my youngah days, I could sometimes hear the high-pitched whine of
> television receivers (horizontal scan, right? ~15kHz?). Not any more.


I can hear some SVGA monitors. I've had to retire several becasue the
squeal gave me migranes. :(


--
Anyone wanting to run for any political office in the US should have to
have a DD214, and a honorable discharge.
From: Paul G. on 26 May 2010 21:06
On Wed, 26 May 2010 09:30:31 -0700, Jeff Liebermann <jeffl(a)cruzio.com>
wrote:

>On Tue, 25 May 2010 15:55:38 GMT, Paul G. <paulguy(a)eastlink.ca> wrote:
>
>>www.antennebureau.nl/fileadmin/pdfs/TNO_COFAM_rapport_2003.pdf
>>
>>Interesting report ....
>>Paul G.
>
>Sorry for the delay. Paying work comes first. 89 Pages before my
>morning coffee. Ugh. Document is locked and cannot be copied, which
>means I can't cut and paste quotes. Why make it easy? I'm lazy, so
>I'll paraphrase.
>
>1.1.1 selection of subjects. Half the subjects came from the
>"Monitoring Network for Environmental Health" database of what appears
>to be chronic complainers. Lovely. That's like using cancer prone
>rats for cancer research. It improves the odds of a positive result.
>
It makes the report interesting to see if the complainers (and what
a lot of us would consider nutters) actually CAN sense the EM fields.
Pity about the way they test that, and it doesn't really clinch the
case when they are just marginally better than the placebo.

>1.1.1 selection of subjects. Subjects with coronary disease and
>psychiatric illness have been excluded but they didn't measure the
>blood pressure or heart rate leaving the results to be totally
>subjective.
>
>1.1.2 Experimental Setup. Oh, this is cute. Since none of the
>subjects in the non-complaining group B experience any symptoms when
>exposed to GSM, in order to manufacture valid results, the researchers
>used the RELATIVE level of complaints between the two groups
>(A=complainers, B=non-complainers). So, if everyone that isn't
>hypersensitive feels nothing, the report can still claim a positive
>result. Nice.
>
text extracted by ghostscript:
quote:
"The subjects within group B do not experience complaints at any given
GSM exposure and at any instance that they are exposed. Therefore it
is necessary to perform the study by means of comparing the occurrence
of complaints between groups. As elucidated in Chapter 16 of our study
protocol [26], we have calculated that with a total sample size of 72
subjects we obtain a power of 80% to find statistically significant
results regarding reported complaints between the periods with
exposure and without exposure. The proposed sample size of the
experiment has been capable of statistically detecting a difference of
5% on the cognitive tests that have been used." end of quote
I can't make any sense of this!


>Pg 14 Figure 3.3 shows the antenna arrangement. Note that the
>monitoring antenna (black blob on the end of a stick) is very close to
>the antenna. That's wrong. This experiment is suppose to simulate
>exposure from base stations, not handsets and is therefore using the
>far field. however, the measuring device is in the near field. It
>needs to be at least 10 wavelengths away from the antenna in order to
>get accurate results. At 900Mhz, that would be about 30cm. At
>1800Mhz, that would be about 15cm. From the photo, my guess is about
>10 cm. A more logical monitoring location would be near the subjects.
>

From what I can tell, they measured the field prior to the experiment,
and use the probe close in just to make sure the system was working:

quote:
"Before the experiments, the exposure of 900 MHz GSM�fields, 1800 MHz
GSM�fields and 2100 MHz UMTS�like fields has been defined and
verified, as described in Appendix A. The field strength at the
location of the subjects has been determined not to exceed 1 V/m. "
"To ensure that the prescribed exposure is actually generated, a
monitor probe was used for field verification and logging during the
measurements. The probe is positioned in front of the antennas. "
end of quote

>Pg 23 is in the middle of a nice review of SAR heating research and
>methodology. I like this quote:
> Interestingly, a study by Bernardi[34] showed that the mere
> presence of a non-transmitting GSM phone made a greater
> contribution to the temperature increase that occurred than
> the electromagnetic field.
>Well yes. Also, locking the subjects inside an anechoic chamber, with
>a mess of menacing looking antennas, and being asked dumb questions,
>might also have a similar effect.
>
That's probably why heart rate and blood pressure were not used.
I'd be kinda irritated, and if a chronic whiner, I'd be REALLY
nervous.


>Also, SAR measurements were intended to be used for near field handset
>exposure, not far field cell site exposure. Little of the cranial
>exposure calculations shown in section 5 are valid for far field
>exposure.
>
>The procedures, selection criteria, and double bind exposure details
>appear to be valid and well considered. I have some minor issues with
>the types of tests and questions asked, but nothing worth detailing.
>
>As near as I can decode the results in 11.5 Pg 59, there was a
>statistically significant effect with UMTS (2100MHz) exposure with
>both groups, and nothing else. Oddly, the report complains about the
>"inadequate" RF exposure procedures employed by other researchers,
>while I find their monitoring and measuring procedure to be equally
>poor.
>
>The Conclusions in Section 12 Pg 61 is weird. They found an effect at
>2100 Mhz with 'well being' from group A (complainers) and what appears
>to be me to be inconsistent effects with 900 and 1800 MHz. More
>simply, they found a correlation at one frequency and both groups, but
>everything else was just noise. Interestingly, they did NOT find any
>increase in sensitivity among group A (complainers) as compared to
>group B (non-complainers). My conclusion is roughly the same as
>theirs. There MAY BE some correlation, but the results are far from
>definitive.
>
Appendix E in the report has a good diagram that summarizes the
responses to the "wellness" questions.

here are the wellness questions (translated by google):
1 Dizziness or a sick feeling
2 Fatigue or lack of energy
3 Nervousness
4 Feeling of pressure or tightness in head or body
5 Quick and fast heartbeat without any reason (or pounding
stumps)
6 Headache
7 Restlessness or nervousness
8 Chest pain or breathing difficulties or
feel not enough air have
9 feel guilty
10 To feel annoyed
11 Muscle Pains
12 Rage
13 Difficulties with clear think
14 Being tense or excited feel
15 mind wanders
16 Parts of the body numbness or tingling feeling
17 Thoughts that do not eliminate pushing his
18 Parts of the body to feel weak
19 Being unable to concentrate
20 Easy your patience losses
21 Easily distracted
22 To feel hostility
23 Little attention

Iteresting that question 1 (dizziness) has such a significant
response, double that of the placebo. It does have relevance to the
original posters concerns. Questions 3,8,16,18,21 also have high
response compared to placebo. Other than q.21, they all refer to
physical sensations.
What I find odd is that the subject's responses at 2100Mhz are so
much stronger than 1800 MHz, even though they claimed to have set the
e-field to about 1V/m. Do you think that 20% higher frequency would
make so much difference?

>Also, since the results were not conclusive and haven't been verified,
>the "more research is necessary" catch phrase was invoked on Pg 62.
>
>
>
>Drivel: I once proposed an experiment for RF exposure. Drag in the
>usual collection of random bored volunteers and set them up for an RF
>exposure test. Also, wire them up for an assortment of real time
>physiological measurements. Have them answer some verbal wellness
>questions to keep them occupied. After the test, correlate the
>measurements with the questions and RF exposure. Yes, it's a lie
>detector test. I did a crude dry run with two friends and found that
>they were probably lying on about 25% the wellness questions. Since
>there was no political or financial interest in validating subjective
>RF exposure test methods, the full test was never performed. For a
>list of projects that were funded, see:
><http://en.wikipedia.org/wiki/List_of_Ig_Nobel_Prize_winners>

That site has hours of laughs!

Paul G.
From: Jeff Liebermann on 26 May 2010 22:34
On Wed, 26 May 2010 14:17:56 -0700, David Nebenzahl
<nobody(a)but.us.chickens> wrote:

>In my youngah days, I could sometimes hear the high-pitched whine of
>television receivers (horizontal scan, right? ~15kHz?). Not any more.

15.734 KHz or something like that. When I was about 12, I built a
Heathkit FM stereo multiplex adapter. I could hear the 19 Khz pilot
tone out of the tweeter. I couldn't figure out why nobody else could.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl(a)cruzio.com
# http://www.LearnByDestroying.com AE6KS
From: David Nebenzahl on 26 May 2010 22:40
On 5/26/2010 7:34 PM Jeff Liebermann spake thus:

> On Wed, 26 May 2010 14:17:56 -0700, David Nebenzahl
> <nobody(a)but.us.chickens> wrote:
>
>> In my youngah days, I could sometimes hear the high-pitched whine
>> of television receivers (horizontal scan, right? ~15kHz?). Not any
>> more.
>
> 15.734 KHz or something like that. When I was about 12, I built a
> Heathkit FM stereo multiplex adapter. I could hear the 19 Khz pilot
> tone out of the tweeter. I couldn't figure out why nobody else could.

Man, that's headache material!


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)
From: Jeff Liebermann on 26 May 2010 23:30
On Thu, 27 May 2010 01:06:14 GMT, Paul G. <paulguy(a)eastlink.ca> wrote:

> text extracted by ghostscript:

Good idea. Thanks.

>quote:
>"The subjects within group B do not experience complaints at any given
>GSM exposure and at any instance that they are exposed. Therefore it
>is necessary to perform the study by means of comparing the occurrence
>of complaints between groups. As elucidated in Chapter 16 of our study
>protocol [26], we have calculated that with a total sample size of 72
>subjects we obtain a power of 80% to find statistically significant
>results regarding reported complaints between the periods with
>exposure and without exposure. The proposed sample size of the
>experiment has been capable of statistically detecting a difference of
>5% on the cognitive tests that have been used." end of quote
>
> I can't make any sense of this!

That's what I was mumbling about. What it seems to say is that there
was absolutely no exposure data from Group B (non-complainers) with
GSM at either 900 or 1800. There was some data at 2100. Therefore,
since nobody in Group B felt anything, they'll just generate some
numbers based on the relative level of complaints between the two
groups. It's a little better than fabricating data, but not by much.
I never could figure out how they correlated their "wellness" scores.
Lots of detail on the procedure, but without the raw data to verify
that the proceedures were followed, they could have just cooked the
numbers and nobody could tell.

>From what I can tell, they measured the field prior to the experiment,
>and use the probe close in just to make sure the system was working:

Ok, that makes sense. Still, it's kinda dumb stuffing the probe
directly in front of the antennas, which is guaranteed to produce
weird measurements, affect the antenna patterns, and affect the
exposure levels.

>>Well yes. Also, locking the subjects inside an anechoic chamber, with
>>a mess of menacing looking antennas, and being asked dumb questions,
>>might also have a similar effect.
>>
> That's probably why heart rate and blood pressure were not used.
> I'd be kinda irritated, and if a chronic whiner, I'd be REALLY
> nervous.

If they had recorded those two, I could get a minimal indication if
the subject was lying on the wellness tests. They dropped it probably
to avoid correlating wellness scores with nervousness. If I were
doing it, I would probably dump the LCD touch screen, and run the test
orally, so I could use a voice stress analyzer.
<http://en.wikipedia.org/wiki/Voice_stress_analysis>

>Appendix E in the report has a good diagram that summarizes the
>responses to the "wellness" questions.
>
>here are the wellness questions (translated by google):
>1 Dizziness or a sick feeling
>2 Fatigue or lack of energy
>3 Nervousness
>4 Feeling of pressure or tightness in head or body
>5 Quick and fast heartbeat without any reason (or pounding
> stumps)
>6 Headache
>7 Restlessness or nervousness
>8 Chest pain or breathing difficulties or
> feel not enough air have
>9 feel guilty
>10 To feel annoyed
>11 Muscle Pains
>12 Rage
>13 Difficulties with clear think
>14 Being tense or excited feel
>15 mind wanders
>16 Parts of the body numbness or tingling feeling
>17 Thoughts that do not eliminate pushing his
>18 Parts of the body to feel weak
>19 Being unable to concentrate
>20 Easy your patience losses
>21 Easily distracted
>22 To feel hostility
>23 Little attention

I suffer from all the above even without RF exposure.

>Iteresting that question 1 (dizziness) has such a significant
>response, double that of the placebo. It does have relevance to the
>original posters concerns. Questions 3,8,16,18,21 also have high
>response compared to placebo. Other than q.21, they all refer to
>physical sensations.

There's another problem. The list is too long. People taking such
tests always are in a rush (to get out of there). If the list is
presented on paper, one typically starts at the top, checks off a few
items, and then thinks "that's enough". If the list is presented on
an LCD screen, one at a time, where one is asked "Yes/No" to each of
the symptoms, the opposite happens. Near the end of the list, people
tend to feel guilty pushing no all the time, and throw in a few yes
answers for balance. Somewhere in my pile of papers is a study done
on such "check all that apply" lists, which demonstrates the effect.

Oddly, the most common real RF complaint I can recall is hearing tones
or noises. That makes some sense with the 217Hz GSM pulse rate. I've
seen ear rings respond to this. Also, an aluminum coated fire
fighters jacket. It's subtle, it's real, but it's not on the list.

What I think would have made more sense is to ask the participant
"What do they feel different from when they entered the room" and have
the researchers tabulate the results in general catagories.

> What I find odd is that the subject's responses at 2100Mhz are so
>much stronger than 1800 MHz, even though they claimed to have set the
>e-field to about 1V/m. Do you think that 20% higher frequency would
>make so much difference?

No difference, unless there are some resonance effects. I wonder if
any of the participants brought their own cell phones. It wasn't
mentioned in the test procedure. Table 6.1 shows the order of
frequency testing, which looks symmetrical in both time and block
order. Therefore, I don't think there would be a time effect (i.e.
we're late and I want to get out of here). Perhaps the Agilent RF
generator made different noises on 2100 MHz just outside the room. I
can't think of anything better.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com jeffl(a)cruzio.com
# http://www.LearnByDestroying.com AE6KS
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