Millie Tess

Millie Tess

Millie Tess is a very small solid state teslacoil, designed to run from a battery supply and to be as compact as possible,

Primary: 2T 1mm emameled copper wire.
Secondary: 2" tall 0.8" diameter, 400T on overflow pipe 7/8" diameter. wound with 0.125mm Wire.
Topload: 2" wooden toy lorry wheel covered in Aluminium foil.

At present Millie Tess is running from single IRF840 mosfet electronic drive, and its giving about 1.25" arcs to air with a battery voltage of 76v

Current Circuit (Subject to change.)

Old Circuit

Older Circuit


First light, running from 66V,

Its got streamers, its arcing, and it lights a flourescent tube , it must be a teslacoil!!









Running from 12V it'l light a flourecent tube from abut 5" away.

Loads of playing later....

I've moved the primary coil higher up the primary, It now sits 1/3 of the way up the coil, this improved the coupling and added about 1/3" to the spark length. 

After speaking to Richie Burnett about the experements he was doing into HF coils (see his HF-SSTC) I made more improvements.

Mosfet drive now uo to +/- 10V, It now runs cooler and I'm getting much better sparks. I've made the mark width longer as I can now risk more power into the mosfet.

I've changed the circuit to a self resonant one (See current circuit above) so I don't get the de-tune when anything gets near it.

Click the picture for a short movie of the output of Milletess at a low break rate. I have since improved the break rate to around 15BPS with the same size of output.. 


Millie Tess complete with driver and batteries..

File:https://www.extremeelectronics.co.uk/old/coils/millietess/millitess.php