[116691] in Cypherpunks
RE: The benefits of e-field shielded bedding
daemon@ATHENA.MIT.EDU (Bill Stewart)
Wed Aug 18 05:20:52 1999
Message-Id: <3.0.5.32.19990818015040.009a6950@idiom.com>
Date: Wed, 18 Aug 1999 01:50:40 -0700
To: "Lucky Green" <shamrock@cypherpunks.to>, "John Young" <jya@pipeline.com>
From: Bill Stewart <bill.stewart@pobox.com>
Cc: <cypherpunks@toad.com>
In-Reply-To: <NDBBIFGOKODBCKDGJDKLCEGJCDAA.shamrock@cypherpunks.to>
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Reply-To: Bill Stewart <bill.stewart@pobox.com>
At 01:38 PM 8/16/99 -0700, Lucky Green wrote:
>A 100dB attenuation figure alone means little. At which frequencies are the
>100bB attenuation achieved?
>
>--Lucky Green <shamrock@cypherpunks.to>
Good point. We did our testing at 450MHz, but the room was certified
for near-DC up to 5 or 10 GHz, I think. As you get above that,
wavelengths become short enough that it's much easier to penetrate
the holes that you use for airflow and fiber optic connectors.
Of course, when we were running 8MHz PCs and 1-6 MIPS VAXen,
there really wasn't much energy above that; these days when
a cheap PC is 400 MHz there's a lot more harmonic energy that
might carry signals that can leak out.
Thanks!
Bill
Bill Stewart, bill.stewart@pobox.com
PGP Fingerprint D454 E202 CBC8 40BF 3C85 B884 0ABE 4639
