Hi John,
Don't have a good explanation yet as I am hesitant to take apart one of
the supplies that is the worst offender as it is the supply for a D-Link
router I have. I am beginning to formulate possible mechanisms. But from
the point of view of equipment, supplies that do this should not be
used. I have been using a simple test setup (on a normal lab bench, not
a standards based setup) that would suffice for prescreening supplies.
There is some sort of discharge happening and the delay could be the
time it takes for a discharge to form. I have been able to repeat the
results with ESD as the stimulus in three different labs using different
equipment.
Doug
University of Oxford Tutor
Department for Continuing Education
Oxford, Oxfordshire, United Kingdom
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On 11/4/14 2:07 PM, John Woodgate wrote:
In message <[email protected]>, dated Tue, 4 Nov 2014, Doug
Smith <[email protected]> writes:
The timing of microseconds is orders of magnitude slower than the
size of the test setup relative to the speed of light in conductors,
1 ft/ns in free space and maybe 1.5 to 2 ns/ft in most conductors.
The test setup used about six feet of cable, 12 ns at most.
So do you have any explanation of the delay? I was imagining some sort
of serial build-up of energy, not a 'straight line' propagation effect.
-
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