The Black Hole......

Howie, I am not familiar with this term. Can you explain what you mean please.

Not within the new guidelines, sorry...

Actually that highly technical term is used in the title of one of my favorite books: "Molecular Adhesion and Its Applications: The Sticky Universe," wonderfully written by Kevin Kendall, ISBN-10: 0306465205

Anyone who has ever wondered why adhesives work on some surfaces and not others, why paint sticks, why lubricants work...will find this highly enlightening.

Cheers!
Howie
 
And, I've no idea if a pinhole would advertise itself visually

SKYDROL when pinhole leaking from an aircraft’s pressurized hydraulic system (3000psi nominal) forms a highly atomized mist

(that kills the eyes of everyone in 5m radius. Pain is unbearable the first half an hour, you want to grab your eye pupils out. For the next 4 hours you are off. Eyes look and feel like strawberries)

George
 
Actually that highly technical term
Gotcha. When I was very young I asked my Father why not all the water fell off something when I turned it over. He said it's complicated. Did you notice how some things held onto droplets and other just had a film of water on them?
Yes daddy.
He said, go to the knowing books and look up surface tension and adhesion. I did, and I've been bewildered ever since.
 
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Type out your response, double tap, make sure it’s all in the ‘copy’ margins, select copy......open a new tab for diyaudio (or keep a second open) go to the end of the thread, open a new response, double tap, paste.

Just tried it and it worked......you must have your second tab open for diya first though.

Thanks Bob 🙂 Jn, hopefully that helps with your posting problem!

Tony.
 
JN, I’ve been using a iPad since I joined the forum, other than the infernally unintuitive spell check I’ve never had a issue.
If it’s that your timing out before your done try the copy/paste with second tab of diya.

Or does everything disappear/reset when you time out?
 
[in response to Hans Polak]
As you have the actual data, I find it odd that you do not overlay them to show that they are "unchanged".
Jn, Hans showed us the waveforms as they are represented in typical audio editing application.
There is no provision of overlaying graphical representation of waveforms of different audio files in audio (read = music) editors, that we, mortals use. It is up to you, research people, to fire up your Matlabs, Pythons or what have you, to plot graphs, do overlays and show them to us to prove your point. This is what, I think, Hans was hinting at.

I find the statement "frequency can't be concluded from a time domain signal" as interesting, as all I had to do was examine the zero crossings.
I don't know if you realize it, but graphical waveform representation in audio editing applications are there for user's convenience. They are not ment to be used as measurement tool, as each application has its own way of drawing those waveforms. They do differ from application to application and may even look differently at various zoom levels. How the waveform is drawn between the discrete sample points and how the line is interpolated in graphics department is only known to person who coded the application.
Drawing conclusions about the zero crossings from such representations, in my opinion, makes no sense.

Below is screenshot of our beloved 20kHz raised cosine burst sampled at 88.2kHz loaded in five different audio editors. Now, which one is "the right one" and what can one do with this information? 😉
 

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What happens to the wave when it goes from SF4 to air? Maybe the transistion can be useful? SF4 is heavier than air so interesting options exist.

I'll try to get a dead Quad panel and measure the surface resistivity.

You guys mean SF6 - Sulfur Hexaflouride, right? The tetraflouride is not something you want to use I think.

It may end up being banned at some point, even in power electronics, since it's one of if not the most potent greenhouse gas we know of. Not a problem for small scale use of course.