Small Vacuum Tube Tesla Coil 1

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This is my first working vacuum tube tesla coil (VTTC). This tesla coil is all-tube and even the power supply is tube-based and provides 320VDC. Below is a schematic diagram.

Parts List
V1 - 5Y3
V2 - 6146
R1 - 0.8 ohms, 10W
R2 - 330K ohms, 2W
R3 - 50K ohms, 1W (100K variable resistor optional)
R4 - 47K ohms, 1W
R5 - 40K ohms, 1W
C1 - 20uF 450V electroylic
C2 - 20uF 450V electroylic
C3 - 0.05uF 800V
C4 - 0.025uF 1600V
C5 - 100 to 500pF 600V mica
L1 - 20-30uH choke
L2 - 15 turns 24 gauge on R4
L3 - 15 turns 24 gauge on 3-inch PVC pipe
L4 - 10 turns 24 gauge on 4-inch PVC pipe
L5 - About 285 turns 24 gauge on 2-inch PVC pipe - 6 inches from bottom to top
T1 - 300V, 6.3V power transformer

This tesla coil is based on the Armstrong oscillator. Once running, it gives continous oscillations and works pretty well after it's allowed to warm up for about 30 seconds. It generates about 1/4 inch discharges in the air.

1/4 inch discharges to the air

Plasma in an incandescent light bulb