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After the results from September 11 2001 became available, many people
asked whether the eggs might have been affected by the terrific stresses
on the power grid and big changes in the electromagnetic environment.
There are a number of logical and technical reasons why this is not
likely, and some of these are described here. Other aspects, especially
the logical XOR protections and the empirical findings are described
elsewhere.
REG Design, Computer Power Supply
In response to concerns that changes in the electrical supply grid might
propagate into the behavior of the REG/RNG devices, John Walker supplied
the following observations about the potential for power mains
frequency perturbations in the GCP data.
First of all, each and every REG in the network runs on direct
current produced by a regulated DC power supply: an external
power cube in the case of the Pear REGs, or obtained from the
RS-232 port for the Orion and Mindsong REGs used by the vast
majority of the eggs. The 12 Volt power taken from the RS-232
port is typically produced by a switching power supply in the
computer, which up-converts the incoming mains power to a
higher frequency to reduce the mass of the step-down
transformer which produces the low voltages used by the
PC components. The output of the secondary windings of
this transformer, which of course has the same frequency
fed to the primary--much higher than the mains frequency (say
25 to 100 Khz, as opposed to 50-60 Hz) is then rectified
into DC by diodes, which is filtered to remove residual
ripple by capacitors (which can also be much smaller
thanks to the higher frequency used by the switching
power supply).
The 12 V signals on the RS-232 port which power the Orion
and Mindsong eggs are ultimately derived from the computer's
power supply, but some RS-232 interfaces further complicate
the matter by generating their own ±12 V supplies from the
more abundant +5 V bus using devices called DC/DC converters,
which may itself be a small switching power supply.
Thus, the power supplied to the REG is DC, with the bulk of
the residual ripple at the frequency of the switching power
supply, and the primary cause of fluctuations those due to
load variations in the computer (for example, when the hard
drive seeks or the CPU dissipation changes) which the regulation
Any influence of the mains power frequency should be far less
than those generated within the computer, since to the extent
mains frequency ripple reaches the DC power buses of the
computer the power supply is failing in its task of
providing regulated DC power.
It's quite easy to put some numbers on these matters.
Just hook up an oscilloscope to the 12 V power used by
an REG and measure how much ripple there is at the mains
frequency. I may do this if I can find the time. A USB
port provides substantially more power to a device (2
Watts if I recall correctly, at a more useful 5V), but
there's no reason to believe the quality of the power
(ripple and regulation) is necessarily any better.
Note that even if the REG were battery powered, it remains
immersed in the ambient EM field of the power lines
surrounding it. Since the REG cannot in any case be
perfectly shielded (since it's required to connect to
a computer which is a maelstrom of potential EM
noise ranging almost from DC to daylight), one could
argue power line influences even then.
Finally, recall that whatever power line influences are
asserted must take into account the difference in power
line frequency, which is nominally 60 Hz in some regions
and 50 Hz elsewhere. Most contemporary computers accept
either frequency, so the residual ripple, to the extent
it exists, will be at the frequency of the mains it
is connected to.
In addition to the points John makes, we should add that there
is yet another layer of protection from line fluctuations.
The design of the REGs includes internal power regulation, and in the
Mindsong devices this is in fact a two stage design. The
people who develop research grade REG/RNG devices are of course
aware of the potential for power fluctuation to degrade the
quality of the random source, and so have invested the
necessary effort to mitigate or prevent such influences.
We are confident that such influences are not a viable explanation for
the anomalous deviations that correlate with major events in the world.
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