Tesla coil project and other high voltage projects

Description: A small Tesla Coil (12-inch range), Jacob's Ladder, or an "Antigravity Project" from the book "Electronic Gadgets for the Evil Genius" is being discussed, but sourcing parts for these projects has proven challenging. The book is informative, yet the cost estimates for the projects are significantly higher than expected, often by a factor of 10 to 20. The only website found for purchasing parts is from the book itself, which is quite expensive.

More: There is a need to find suppliers for high-voltage capacitors, avalanche diodes, and high-voltage transformers rated at 10kV or higher. eBay is mentioned as a potential source for these components. For high-voltage transformers, neon sign transformers are generally the most accessible, although availability may vary based on local demand and regulatory constraints regarding voltage, power, and required ground fault sensing electronics. The most commonly available high-voltage transformer is the microwave oven transformer; however, its lower voltage and high current capabilities can pose safety challenges. Caution is advised when working with projects from the Evil Genius series, especially those involving high tension (HT) connections to mains power, as detailed instructions may be insufficient.

A potential source for necessary parts is identified as Farnell, which offers control panel transformers that convert 208VAC to 600VAC down to 115VAC or 230VAC. These transformers can be run in reverse to produce 600VAC or 830VAC, depending on whether isolation from the mains is required. A capacitive voltage multiplier can be employed to achieve 10kVDC. The safety implications of using an isolation transformer are debated; while it may provide some protection, if the secondary is grounded, the benefits diminish, particularly in cases of neutral failure or live-neutral reversal. It is crucial to ensure that the insulation of the transformer can withstand both the secondary and primary voltages; the referenced transformer is rated for only 5000VAC, translating to just over 7kVDC, which is inadequate for applications requiring higher voltages.

The construction of a small Tesla coil or Jacob's Ladder involves several key components. The primary circuit includes a high-voltage transformer, which steps up the voltage to a level suitable for the operation of the coil or ladder. The transformer should be selected based on the desired output voltage and current characteristics. For Tesla coils, a spark gap is typically employed to allow for the rapid discharge of energy, creating the characteristic arcs.

In the secondary circuit, a resonant capacitor is used to enhance the oscillation frequency, which is critical for efficient energy transfer. The use of high-voltage capacitors rated for at least 10kV is essential to prevent breakdown during operation. Avalanche diodes may be incorporated to protect the circuit from voltage spikes, ensuring the longevity and reliability of the components.

Safety precautions are paramount when working with high-voltage projects. Proper insulation, grounding techniques, and the use of protective equipment are necessary to mitigate risks. Additionally, a thorough understanding of the circuit's operation and the behavior of high-voltage components is essential for successful and safe experimentation.A small Tesla Coil (12" range), Jacobs Ladder or a "Antigravity Project" from the book `Electronic Gadgets for the Evil Genius`, but I am having a very hard time locating part for these projects. It is a nice book but there project cost estimate is way of the mark (by a factor of 10-20 more). And the only website I have found is the website from the book and charge an arm and leg. Were can I buy high voltage capacitors, avalanche diodes and high voltage transformers in the 10KV range and higher. Does anyone know of a good source for these parts Ebay is the best bet. For HV transformers, neon-sign transformers are generally the most available but this depends a lot on how popular neon signs are in your area, as well as in some cases regulations that restrict voltage/power, or mandate internal groundfault sensing electronics.

The only widely available species of HV transformer is the microwave oven transformer, but their relatively low voltage and high current capability make them difficult and more dangerous to use. Be careful with those evil genius books. I have one and I`m not at all confident that details are explained enough particularly with HT projects working straight off the mains !

I beleive there is a website the author sells the required parts from Farnell sell control panel transformers for converting 208VAC to 600VAC down to 115VAC or 230VAC. You could run one in reverse to give 600VAC or 830VAC, depending on whether you need isolation from the mains or not.

You can then use a capacitive voltage multiplier to give 10kVDC. Whether isolation from the mains increases safety is debatable. If you use an isolation transformer and want the secondary to float, you need to ensure the insulation can withstand the secondary plus the primary voltage. The transformer I linked to above is only tested to 5000VAC which is just over 7kVDC and is not good enough for you so you`ll need to connect the secondary to earth.

If you`re connecting the secondary side to earth then an isolation transformer offers little protection except for perhaps a broken neutral on the mains side or live neutral reversal.