The bottom end of the secondary is insulated with two surgical gloves that fit inside (there is not much trouble, because here, the voltage value is minimal). The upper end is insulated with plasticine (it can be easily modelated). The top wires are insulated with black plastic adhesive band to prevent corona. The toroid sit on a piece of hard paper covered with aluminium foil.
The next step will be a longer secondary to allow a longer spark. This secondary have D/L = 1/ 3.2 because I used very fine wire ( 0.25 mm diameter). If I would use a D / L = 1/ 5 I would have 1500 turns (much more ohmic resistence) and a lower gain factor. |
