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Re: Transmission Noise Pilot study

Subject: Re: Transmission Noise Pilot study
From: "Gregory O'Drobinak" gmo_dunes2
Date: Mon Mar 21, 2011 8:39 am ((PDT))
Rob:

Good news about the Reserve Board!

As for my attachment, it appears that this newsgroup stripped off my '.rtf'=

file. Is that normal for Yahoo newsgroups? However, I did send a personal e=
mail
to you & Rich P., so you should have gotten that. In any case, I decided to=

include the links at the end of this email so that everyone can look them o=
ver.

I would think that trying to record underneath 345 KV lines, or even very c=
lose
to them, would be difficult to do without picking up loads of hum. I would =
be
surprised if any condenser mic could reject the strong electric field which=

could easily be 20 KV at 6 feet above the ground under said wires. I would =
be
very careful when handling recording equipment under those wires and I woul=
d try
to keep everything (cords & all!) at the same distance to ground level. May=
be
having everything lying on the ground, micd included, would be the best way=
 to
try to record it.

Sennheiser makes an optical mic that would not be affected by the
strong electric field and the response goes up to 40KHz, but the self noise=
 is
44dBA! Optimics has one that has lower self noise (31 dBA), but the frequen=
cy
response is quite limited. So to faithfully record the acoustic sound close=
 to
the wires looks like a challenging problem. I'll see if I can find more inf=
o
about this.

Take care,

Greg


Effects on birds, wildlife and plants:
http://audubon-omaha.org/bbbox/nabs/pdtg1.htm
http://www.wildlandscpr.org/node/211
http://eng.hi138.com/?i42972
http://scienceblogs.com/notrocketscience/2009/03/power_lines_disrupt_the_ma=
gnetic_alignment_of_cows_and_deer.php

www.polarresearch.net/index.php/polar/article/download/6532/7365
http://psc.wi.gov/thelibrary/publications/electric/electric10.pdf
http://www.academicjournals.org/AJB/PDF/pdf2010/27Sep/Demir.pdf
http://www.fas.org/ota/reports/8905.pdf
http://www.jstor.org/pss/2426995
http://www.savethelampasas.org/EK-%20Transmission%20line%20concerns.pdf

EMF field plots (electric & magnetic) and Environmental Impact:
http://www.emfs.info/Sources+of+EMFs/Overhead+power+lines/
http://www.scribd.com/doc/25544985/Environmental-Impact-of-Transmission-Lin=
es
http://efile.mpsc.state.mi.us/efile/docs/13934/0071.pdf
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1637318/pdf/envhper00486-0143.p=
df
http://www.osmak.ae/featuredarticle.html#

Human Effects:
http://siliconvalleyrealestateinfo.com/electric-and-magnetic-fields-emfs-an=
d-how-they-effect-real-estate-prices.html

http://www.niehs.nih.gov/health/topics/agents/emf/
http://www.amazon.com/Electro-Magnetic-Field-Sper-Scientific/dp/B001EU9PQ0/=
ref=3Dwl_it_dp_oie=3DUTF8&coliid=3DI3DAR4XM4U9DKF&colid=3D3085QP7X1ZCF2

http://www.epa.gov/radtown/power-lines.html
http://www.ehib.org/emf/longfactsheet.PDF
http://www.who.int/peh-emf/publications/sci_journal/en/index.html



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