> Rich says:
>
> >At least two people have seen the 220's normal damped wave
> >ringing at 110MHz on a spectrum analyzer.
Peter replied:
> How does one see that on a spectrum analyser? Because it's not a
> continuous signal in the time domain, it's not the thing to look for with
> a spectrum analyser.
>
> Remember too, that a spectrum analyser, given half a chance, will lie like
> a personnel manager!
People who haven't thought clearly about what a spectrum analyzer
does often misuse or misinterpret them.
If you read the "information" on the spectrum analyzer "proof",
you'll see during an arc two people have claimed to see 100 MHz
blips. That sure doesn't surprise me, since the arc would have
energy all across the spectrum. Where ever the sweep happens to
be at the moment of the arcs, that's where you'll see deflection.
As a matter of fact, in one PA system I designed using an arc
detector, I detected any arc regardless of frequency by sampling
the transmission line for energy at 50 kHz. I could just have well
have done it on any frequency where the PA wasn't actually being
used.
73, Tom W8JI
w8ji@contesting.com
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