nitpick - watts is a measure of speed - joules per second
I'd call it a rate, not a speed. Speed is specifically distance per unit time, not energy per unit time.
What 50,000 watts of RF energy sounds like through a jumper cable
31–40 of 163 posts
Re: What 50,000 watts of RF energy sounds like through a jumper cable
#3219 comments and not even one mentions that Watt, with a capital W, measures power, and not energy? I'm assuming 90% of posters know this, but it still bugs me. A modest proposal: "What 50 kilowatts of RF power sounds like through a jumper cable"
> What 50 kilowatts of RF power sounds like through a jumper cable
And you still got it wrong.
Re: What 50,000 watts of RF energy sounds like through a jumper cable
#33So dumb questions: Why were they shorting out the tower? (What was the purpose of the cable) What are those rubber things? What would happen to a bird that landed on the tower (not grounded) What about a large metal helicopter (if it didn't crash)?
The bird would be fine, due to the way parallel circuits work (Very little power travels through the more resistant one of two parallel circuits.)
The bird would be dead. RF power will happily fry tissue if you get close enough to the radiator.
Re: What 50,000 watts of RF energy sounds like through a jumper cable
#34Re: What 50,000 watts of RF energy sounds like through a jumper cable
#3519 comments and not even one mentions that Watt, with a capital W, measures power, and not energy? I'm assuming 90% of posters know this, but it still bugs me. A modest proposal: "What 50 kilowatts of RF power sounds like through a jumper cable"
> What 50 kilowatts of RF power sounds like through a jumper cable And you still got it wrong.
This reminds me of https://www.youtube.com/watch?v=Gg_yzRWy9HM
Re: What 50,000 watts of RF energy sounds like through a jumper cable
#36Earlier quoted context omitted.
What makes it worse than just a burn or a burn due to an electrical shock?
Normal burns are usually localized to the surface of your skin. RF burns conduct all the way through your tissue, heating from the inside. It's a much deeper, more painful burn that takes an abnormally long time to heal. (Or so I'm told. So far I've been able to avoid experiencing one myself.)
Unfortunately I wasn't able to avoid the experience, I hit the screw on a silver trimmer in an end stage while looking at another one. Nasty little burn with dead tissue in the center and living tissue all around it. 35 years later it is still there, I don't expect that it will ever properly heal, it's a dead bit in the middle of a living finger.
Re: What 50,000 watts of RF energy sounds like through a jumper cable
#37Earlier quoted context omitted.
Same way as a plasma speaker https://www.youtube.com/watch?v=PJpn2PzhvP4
https://www.youtube.com/watch?v=hgll-XTqcS4 (youtube-dl with mpv fullscreen recommended)
Dumb question is it also creating the piano like sound in that video with the electricity? Very cool to watch.
Re: What 50,000 watts of RF energy sounds like through a jumper cable
#38Earlier quoted context omitted.
I think that usage is OK. It's like saying "40W of light". In this case, it tells us there's some RF energy and also that it's RF energy of the "50 kW" type.
I think "40 W of light" is a great example of why this imprecise, or quite frankly, incorrect usage is troublesome. 40 W of old timey lightbulb light is useful if you want to sit close and read a book in the evening, whereas 40 W of a modern LED bulb light is a great thing to have if you want to fend of a pack of marauding undead.
It's not actually as imprecise as it sounds. A 40W light bulb might produce 1W of light and 39W of heat. Watt is the normal unit of measure for radiant flux, and the lumen is nothing more than "luminous flux" which is radiant flux weighted according to its spectrum.
Re: What 50,000 watts of RF energy sounds like through a jumper cable
#39Wow, can anyone explain this?
The voltage applied to the cable is directly proportional to the audio signal, overlaid on a ~1 MHz carrier. All you need is a mechanism that transforms those voltages into vibrations or pressure waves. Presumably, since it seems to happen only when he's striking an arc, it's related to the local heating of the air in the gap ... But I guess it could be electromagnetically induced vibrations of the cable or the tower…
That was one specific station - the infamous WLW / W8XO - the first and only US station authorized to operate at 500kW of power.[1]
To give you an idea of how powerful that is, take a look at their coverage map: http://i.imgur.com/Aigz1Zh.jpg
The back story is kind of interesting. It was run by Powel Crosley - a sort of 1930's version of Elon Musk. Advertising revenues from the station were so successful he applied to increase the limit from 500kW to 750kW(!).
It's a big deal in the ham community, but I only learnt latter that while US stations were limited to 50kW - other parts of the world didn't have such restrictions. Parts of the Middle East have 2,000kW stations. [2]
You can get a full download on the Crosley WLW station in this video: https://www.youtube.com/watch?v=CbHjcwIoTiY
Re: What 50,000 watts of RF energy sounds like through a jumper cable
#40Earlier quoted context omitted.
https://www.youtube.com/watch?v=hgll-XTqcS4 (youtube-dl with mpv fullscreen recommended)
Dumb question is it also creating the piano like sound in that video with the electricity? Very cool to watch.
Yes! That's all done with the plasma channel expanding and (therefore) contracting at audible frequencies.
(edit: I'm way wrong on the piano. arjie's correct about the backing track)