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Bud-- Bud-- is offline
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Default Surge / Ground / Lightning

wrote:
In alt.tv.tech.hdtv bud-- wrote:

| Previously you said Martzloff "flubbed the experiment".

I remember that. You were telling me about some information he had
obtained from some experiment.

| Now you agree with Martzloff that branch circuit must be 200m for
| transmission line behavior with 1.2 microsecond rise time.

That's not a result of an experiment.


"*From this first test*, we can draw the conclusion (predictable, but
too often not recognized in qualitative discussions of reflections in
wiring systems) that it is not appropriate to apply classical
transmission line concepts to wiring systems if ..."

As usual, you don’t know what was written.

I'm not so sure the exact distance
is 200m for that exact rise time. But that is a subjective thing.


Quit equivocating. Where is your cite. Like for nanosecond risetimes.


| You say that doesn't apply because surges are faster. Martzloff uses 1.2
| us because that is a standard rise time for surges produced by lightning
| as defined in IEEE standards.

Martzloff did not say that was a defined standard in the statement you
quoted. He just used it as an example to come up with the 200m figure.


He used it because 1.2/50 (voltage) is an IEEE standard. The 8us from
w_’s engineer is another standard (8/20 current).


| w_' professional engineer source says 8 micoseconds with most of the
| spectrum under 100kHz.

Even with 1 nanosecond rise time, most of the energy will be present in
the spectrum below 100 kHz. That means nothing when the surge is strong
enough to have energy above some frequency that is relevant to the whole
system involved that can do damage. That frequency might be 100 Mhz for
some thing, and 1 GHz for other things.


Still missing – your source. Nanosecond risetime. 100MHz spectrum.


| You still have *no sources that support your belief* that risetimes are
| far faster.

I have experience and observation for that. I need no more.


Lots of people have experience and observation with flying saucers.

The rest of us want a source.

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bud--