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Post by GTCGreg on Dec 2, 2016 15:37:17 GMT
and near field charging is closer to a two piece transformer than it is to wireless power transmission. And that's exactly what a Tesla coil is. The only difference is a Tesla coil operates at much higher frequencies than the 60Hz power line. Many of these wireless charging stations also operate at higher frequencies. |
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Post by the light works on Dec 2, 2016 15:50:34 GMT
and near field charging is closer to a two piece transformer than it is to wireless power transmission. And that's exactly what a Tesla coil is. The only difference is a Tesla coil operates at much higher frequencies than the 60Hz power line. Many of these wireless charging stations also operate at higher frequencies. a tesla coil operates at whatever frequency you feed it. it is essentially an extremely high gain transformer - which is available in several styles. some operate more quietly than others. sometimes quiet is not a desirable feature. |
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Post by GTCGreg on Dec 2, 2016 16:15:26 GMT
And that's exactly what a Tesla coil is. The only difference is a Tesla coil operates at much higher frequencies than the 60Hz power line. Many of these wireless charging stations also operate at higher frequencies. a tesla coil operates at whatever frequency you feed it. it is essentially an extremely high gain transformer - which is available in several styles. some operate more quietly than others. sometimes quiet is not a desirable feature. The RF frequency of a Tesla coil is determined by the size of the capacitor and the inductance of the primary coil. The sound you hear from the arc of a Tesla coil is 120Hz produced by the doubling of the 60Hz power line frequency feeding the arc gap. Some people have modulated that power supply so the arc acts like a speaker and can even produce music. This is exactly how an AM radio transmitter works. The output frequency is fixed but the power output is modulated with the program material by varying the power to the final RF amplifier connected to the antenna. A Tesla coil is actually a spark-gap transmitter and can be used to transmit a radio signal over great distances (thousands of miles) if connected to an antenna. I built a Tesla coil transmitter back when I was in high school. It was a smaller Tesla coil with about a 3 foot secondary coil but it still wiped out every radio and TV within a mile of the house. |
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Post by Lokifan on Dec 2, 2016 16:20:30 GMT
I've seen Arc Attack in person at the local Makerfaire.
They're even better live than on YouTube.
Highly recommended.
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Post by the light works on Dec 2, 2016 16:34:14 GMT
okay, I dug, and the coil has two frequencies - one is based on the native cycle frequency of the AC power supply, and the other is an imposed frequency that is used to control the pitch of the discharge.
so you feed it with your mains AC frequency power, and it operates at a multiple of that - but then you switch the feed at your desired frequency to make your music.
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Post by the light works on Dec 2, 2016 16:35:07 GMT
I've seen Arc Attack in person at the local Makerfaire. They're even better live than on YouTube. Highly recommended. some things just cannot be reproduced on 2" speakers. |
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Post by GTCGreg on Dec 2, 2016 16:59:00 GMT
okay, I dug, and the coil has two frequencies - one is based on the native cycle frequency of the AC power supply, and the other is an imposed frequency that is used to control the pitch of the discharge. so you feed it with your mains AC frequency power, and it operates at a multiple of that - but then you switch the feed at your desired frequency to make your music. The "native frequency" is determined by the resonant frequency of the tank circuit formed by the capacitor and the primary coil. This is a radio frequency signal that your ears cannot hear. Your program material, such as music, is used to modulate a DC voltage supplying the power to the tesla coil. At this point, there is no AC line frequency to be found. It was filtered out in the DC power supply. |
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Post by the light works on Dec 2, 2016 17:17:18 GMT
okay, I dug, and the coil has two frequencies - one is based on the native cycle frequency of the AC power supply, and the other is an imposed frequency that is used to control the pitch of the discharge. so you feed it with your mains AC frequency power, and it operates at a multiple of that - but then you switch the feed at your desired frequency to make your music. The "native frequency" is determined by the resonant frequency of the tank circuit formed by the capacitor and the primary coil. This is a radio frequency signal that your ears cannot hear. Your program material, such as music, is used to modulate a DC voltage supplying the power to the tesla coil. At this point, there is no AC line frequency to be found. It was filtered out in the DC power supply. a tesla coil is a two stage transformer - the primary coil is a traditional iron core transformer, which feeds the spark gap coil (or the solid state equivalent) are you saying you could power a tesla coil directly from a battery? even rectified DC is still pulsed DC, and it still has a line frequency. |
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Post by Lokifan on Dec 2, 2016 18:10:38 GMT
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Post by GTCGreg on Dec 2, 2016 19:24:42 GMT
a tesla coil is a two stage transformer - the primary coil is a traditional iron core transformer, which feeds the spark gap coil (or the solid state equivalent) are you saying you could power a tesla coil directly from a battery? even rectified DC is still pulsed DC, and it still has a line frequency. You can power a Tesla from any voltage source, either AC, DC or modulated provide the voltage of your source is great enough to jump the spark gap in the primary coil circuit of the Tesla coil. This is typically 10,000 volts or higher. If you want to connect enough batteries in series to give you 10,000 voltages than it will work. About 7500 flashlight batteries should do the trick. The "singing" Tesla coils use a high voltage modulated power supply in place of the line voltage iron core transformer. The traditional way a Tesla coil is powered is from a neon sign or oil burner ignition transformer. The Tesla coil I built in high school used an oil burner transformer rated at 12kV output. These are the iron core transformers that you are referring to. The actual transformer that the Tesla coil forms is an air core transformer. It consists of 10 to 50 turns of heavier wire wound around the base of the secondary coil. The secondary coil consists of thousands or even tens of thousands of turns of much finer wire. The frequency of the voltage applied to the primary winding is RF (radio frequency). It is created by pulsing the current through the primary coil. It is the spark gap that causes this high frequency pulsing. Don't confuse this spark gap with the large sparks generated at the top of the Tesla coil. The control spark gap is near the base and is only an inch or two long. You will also find some type of high voltage capacitor wired in parallel with the primary coil. The capacitor and primary coil form a tank circuit that resonates at the RF frequency of the Tesla coil. This frequency can vary depending on the size of the capacitor and the inductance of the primary coil. The capacitor I used in my Tesla coil consisted of a one foot square pane of glass with copper foil glued to each side.  |
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Post by silverdragon on Dec 3, 2016 14:10:32 GMT
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Post by silverdragon on Dec 7, 2016 9:43:11 GMT
On a side related note....
I found out that our lunatic govt were serious about the UK having its own functional space agency by 2020...
Wht da duck?...
This isnt a joke, but it does lead itself into one, so I may as well read it like one.
Its headquarters would be in Swindon.
You can hear the radio messages now cant you...
"Swindon, we have a problem"
"Yeah mate, we're in Swindon........................"
For the yanks, Swindon, well, its like a slightly warmer city in Alaska without any nice people in it at all.
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Post by GTCGreg on Dec 7, 2016 14:30:22 GMT
Did they pick Swindon because it's a remote location and a safer place to launch, or for other reasons? We do most of our space launches from Cape Canaveral which is right on the Atlantic coast. That way, if something goes wrong, the debris falls into the ocean and not on someone's house.
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Post by the light works on Dec 7, 2016 14:31:43 GMT
Did they pick Swindon because it's a remote location and a safer place to launch, or for other reasons? We do most of our space launches from Cape Canaveral which is right on the Atlantic coast. That way, if something goes wrong, the debris falls into the ocean and not on someone's house. or falls onto swindon. |
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Post by GTCGreg on Dec 7, 2016 14:35:38 GMT
Did they pick Swindon because it's a remote location and a safer place to launch, or for other reasons? We do most of our space launches from Cape Canaveral which is right on the Atlantic coast. That way, if something goes wrong, the debris falls into the ocean and not on someone's house. or falls onto swindon. Maybe that's why they picked Swindon. They are use to dodging rocket pieces. |
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Post by the light works on Dec 7, 2016 15:11:11 GMT
Maybe that's why they picked Swindon. They are use to dodging rocket pieces. I was suggesting more because the british space agency didn't like anyone in Swindon, either. |
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Post by silverdragon on Dec 8, 2016 9:21:50 GMT
Maybe that's why they picked Swindon. They are use to dodging rocket pieces. I was suggesting more because the british space agency didn't like anyone in Swindon, either. I would think its more that if say for instance the whole of swindon got washed by an explosion from an exploding booster rocket, "So what?.. its Urban Regeneration" If you have ever watched the series "The office", and seen what "A bunch of loosers" that lot are, well, swindon is where its based. There are jokes about Birmingham, Used to be a roundabout on the M6 [motorway], the only good thing to come out of Birmingham is the road home, and all of that, but at least the people of Birmingham can say they are better than Swindon?.. There is Birmingham, Milton Keynes, and then at the bottom of the pile, Swindon. If there ever was a home for the Telephone Sanitisers that the Golfrinchians wanted to leave behind, then it was Swindon...* [Hitchikers Guide reference]I believe Swindon is to space as Huston is to NASA, its the flight control centre, not the launch pad, mainly because Swindon is where they base a lot of things like that, Telephone call centres etc?.. |
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Post by GTCGreg on Dec 8, 2016 14:56:35 GMT
I guess we'll put you down as a no for vacationing in Swindon.
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Post by the light works on Dec 8, 2016 15:11:03 GMT
I was suggesting more because the british space agency didn't like anyone in Swindon, either. I would think its more that if say for instance the whole of swindon got washed by an explosion from an exploding booster rocket, "So what?.. its Urban Regeneration" If you have ever watched the series "The office", and seen what "A bunch of loosers" that lot are, well, swindon is where its based. There are jokes about Birmingham, Used to be a roundabout on the M6 [motorway], the only good thing to come out of Birmingham is the road home, and all of that, but at least the people of Birmingham can say they are better than Swindon?.. There is Birmingham, Milton Keynes, and then at the bottom of the pile, Swindon. If there ever was a home for the Telephone Sanitisers that the Golfrinchians wanted to leave behind, then it was Swindon...* [Hitchikers Guide reference]I believe Swindon is to space as Huston is to NASA, its the flight control centre, not the launch pad, mainly because Swindon is where they base a lot of things like that, Telephone call centres etc?.. you're overanalyzing a perfectly good joke. |
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Post by Lokifan on Dec 8, 2016 15:42:50 GMT
Personally, I'd have picked Plymouth for a launch site. Anything goes wrong, and it lands in the Channel--or France. Win-win.  |
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