Hi Mario,
> Istantaneous power of a burst has little to do with RMS power since
> the duty cycle is generally irrelevant. A KW amplifier can generate a
> peak but the power content of the burst is well within cthe onnector
There is no question that statement is NOT correct.
Once you trigger the arc, from excessive voltage, the arc will stay
until something removes the ionized gas from the arc.
A low energy pulse of excessive voltage can cause much damage
when it is followed by sustained normal power. It also can cause
accumulated damage as it slowly (if the arc is not sustained long)
carbon tracks any dielectric.
This is one of the most common failure modes in high power
systems.
> in favour of UHF connector was the current, now it seem has been
> "moved" to voltage rating. As well as the load capacitor in a PI
It is both. Current is a duty cycle failure, where time is long. Arcing
can wipe out a component in a fraction of a second. The arc by
itself is NOT the problem, it is the current that flows through the
plasma and the heat that is the problem.
When you look at either result, you can not tell which caused the
problem. All you see is a toasted connector.
> thank, the capacitors of low pass in PA output or the antenna relay,
> the connector of a 1500 W PA doesn't require to withstand thousand
> kilovolts.
They indeed do, if you do not want field failures.
73, Tom W8JI
W8JI@contesting.com
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