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Hi Dave,<br>
<br>
Fernando says he's done things like that and prefers not to, but
maybe we could. Still it's hard to draw quantitative conclusions
from such measurements.<br>
<br>
<br>
<br>
<br>
<br>
On 04/05/2012 04:54 PM, David Lawrence wrote:
<blockquote cite="mid:4F7E0677.1070004@jlab.org" type="cite">
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<br>
Hi,<br>
<br>
This may be a silly question, but can't we just hook a cell-phone
antenna to an oscilloscope with a FFT feature? The antenna are
designed based on a fractal pattern and so have are sensitive to a
very wide range of frequencies, but are compact and so can be used
to localize the source to a smaller area. We'll have portable
scopes around anyway.<br>
<br>
Regards,<br>
-David<br>
<br>
On 4/5/12 4:47 PM, mark stevens wrote:
<blockquote cite="mid:4F7E04FE.2010000@jlab.org" type="cite">Hi
Elliott, <br>
<br>
The spectrum analyzer with a hand-made antenna is all I have
seen used here at Jlab. I did a property search with the terms
"emi" and "noise" and saw nothing. I have previously used a
portable AM radio, tuned between stations, to pick up noise - it
is remarkably sensitive (it will pick up SCR noise, for example,
like that coming from light dimmers or switching power
supplies). There are commercial products that are "EMI Noise
Analyzers", but they are expensive. Some companies will rent
them. <br>
<br>
Best Regards, <br>
<br>
Mark Stevens <br>
<br>
On 4/5/2012 2:08 PM, Elliott Wolin wrote: <br>
<blockquote type="cite">Hi, <br>
<br>
Fernands says he currently has no good way to measure radiated
noise <br>
other than jury-rigging something together using a piece of
wire and <br>
some sort of spectrum analyzer. Does anyone know of real
system at JLab <br>
that can measure radiated noise? <br>
<br>
<br>
</blockquote>
<br>
<br>
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<pre class="moz-signature" cols="72">--
Sincerely,
Elliott
================================================================================
Those raised in a morally relative or neutral environment will hold
no truths to be self-evident.
Elliott Wolin
Staff Physicist, Jefferson Lab
12000 Jefferson Ave
Suite 8 MS 12A1
Newport News, VA 23606
757-269-7365
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