A transformerless Tesla coil

Continuing the studies about directly coupled multiple resonance networks operated as Tesla coil like devices, I built a 6th-order system, that is equivalent to a ` Tesla magnifier `, but without a transformer. The schematic diagram is shown below: This circuit has several potential advantages over a simpler directly coupled Tesla coil : Faster en
A transformerless Tesla coil - schematic

ergy transfer from C1 to the distributed terminal capacitance C3, what results in smaller losses, greater efficiency, and insensitivity to tuning precision. The wider notches in the primary waveforms tend to cause fast quenching of the spark gap, at the first notch, trapping all the energy in the high-voltage part of the circuit. The design is restricted by the absence of the extra degree of freedom allowed by a transformer in the classic magnifier circuit, with the maximum voltage gain being forced by the ratios among the resonance frequencies, but the transformerless construction is simpler. The system was designed to have three resonance frequencies, in the ratio 5:6:7. In this way it can transfer the energy in C1 to C3, ignoring losses, in just three cycles (in 12. 5 µs), instead of in the 11 cycles (in 37. 6 µs) required by the 4th-order directly coupled system with the same input (identical) and output (almost identical) capacitances. The power supply is a 5000 V, 30 mA neon sign transformer with a single floating output, that charges the capacitor C1, that is then discharged through a multiple spark gap starting the energy transfer transient. C1 is a 5. 09 nF "MMC" capacitor, the same that I used with the 4th-order system. L3, the output resonator coil with 28. 2 mH, the terminal with a telescopic antenna, the NST and the spark gap are also the same. Their description can be seen here. The other two coils are L1,...

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