On Wed, 7 Oct 2009 02:13:52 +0100, "christofire"
wrote:

The effects on equipment of repetitive cycles of incident electric field
strength with alternating polarity, constant period and equal rise and fall
times (AKA a sine wave), whether continuous or 'pulsed', are different from
the effects of an incident pulse of electric field strength with a short
rise time that is not broken up into harmonic cycles. The latter can induce
a high voltage pulse that is wideband in the same manner as the result of a
lightning strike, and this can propagate through an installation causing
damage. The former cannot do that. Of course, I appreciate the difference
is the spectral width of the incident 'signal'.

Hi Chris,

You are mixing frequency domain with time domain descriptions. Example
repeated from above:
a short rise time that is not broken up into harmonic cycles.

"A short rise time" is made up of an increasingly dense spectrum of
harmonic cycles. It cannot be otherwise.


The example you gave was of the former type, radiation from a microwave
oven, whereas I had written about the latter type.

You are now mixing modulation into the time domain to argue against a
frequency domain solution. Modulation, if anything, adds even more
spectral (harmonic cycle) products.

Besides, I offered you simply reduce the number of modulation cycles,
by their count, to reduce the effect to that of one cycle (of
modulation). A pulse is a modulation of one cycle (however poorly
shaped it may be, and it envelopes a pluarity of SHF cycles).

An open microwave oven
may well cook a human but it won't have much effect on a power cable feeding
a computer other than, perhaps, melting the insulation! A wideband pulse of
electric field of sufficicient strength will damage the computer. But,
evidently, you disagree ...

No, not evident at all. Any "effect" is more a function of amplitude
than a failure to warm insulation:
On Tue, 6 Oct 2009 10:43:10 +0100, "christofire"
wrote:
but how much damage is a pulse of 10 GHz RF going to do?
"How much damage" speaks specifically to that function of amplitude,
not pulse shape, not rise time, fall time, or the rest; and as you are
explicit in giving a specific frequency.... The microwave oven
example suitably answers this. A RADAR example does even better (and
still the results, save for amplitude, are the same).

73's
Richard Clark, KB7QHC