Tiny Tiny Tesla coil

I was cleaning the Lab and had a few parts that were laying around that gave me an idea. I could take a small plastic wire spool, a dead ink pen, a few bent brass bolts, a few tiny low powered capacitors and a few bits of different wire and build a Tiny Tesla coil. Wow big surprise Huh? After about and hour of work and a bunch of McGivering I ended up with this. It works really well and I have more fun with it than I do with many of my larger coils. What next? A series of ultra tiny tesla coils? Twist my arm.

Wireless Electricity

This is based on a project by Marko at 4hv,org. I laidout the PCB in Express PCB.

"The idea behind the project was to create a small tabletop demonstrator of magnetically coupled wireless power transfer, resembling a miniature version of the MIT 'witricity' device. The goal was to keep the circuit simple with easily obtainable parts, and to keep voltage and power levels low so the device is safe for handling and doesn't require special methods of cooling.

The basic idea is to feed a parallel LC tank circuit from an AC voltage source at it's resonant frequency, which allows large reactive current to circulate in the circuit while only real power is being drawn from the source. This sets up a large alternating magnetic field in the inductor, which is designed as a single conductive loop in this case.

Now, another LC tank with load attached is brought in proximity to the excited LC circuit, significant amounts of power can be transferred via weak magnetic coupling between them. This is because AC current itself in the transmitting loop is very large, and inductive reactance of the receiver loop is canceled out by the capacitor.

For a practical device, the AC voltage source had to be substituted with an appropriate oscillator, which would take feedback from the tank circuit itself and hence always drive it at it's resonant frequency.

The circuit of choice was a slightly modified royer oscillator, such as popularly used in CCFL inverters and for flyback drivers.

Input voltage was limited to 15V for safety and because the circuit tends to become unstable at higher voltages."

Table top coil finished.

Here is the first light on my latest coil.

Coil progress

I wound the primary coil and finished all the wiring except for the spark gap and 12v power supply. I also wound the secondary but have yet to photograph it.

Table top Tesla coils.

I have a great combination of parts and performance for a small table top Tesla coil and this will be the second in this line that I have built. This is the lower half of the setup and I still need to wind the Primary and Secondary coils.

I just finished building Franklin's Bells. The bells and hardware are all brass. The terminals are vintage as are the Bakelite standoffs used for the base of the bells and the terminals.

Electrostatic bells like these are often referred to as Franklin's Bells, after the eminent American scientist Benjamin Franklin, who installed them in his house to warn him of approaching thunderstorms, as is recorded in a famous portrait of Franklin observing his set of electrostatic bells as a thunderstorm raged outside. This electrostatic device actually was invented in about 1742 by Andrew Gordon, Professor of Natural Philosophy at the University at Erfurt, Germany. Gordon's Bells constituted the first device that converted electrical energy into mechanical energy in the form of continuous mechanical motion, in this case, the moving of a bell clapper back and forth between two oppositely charged bells.

Franklin made use of Gordon's idea by connecting one bell to a pointed rod attached to his chimney and a second bell to ground. This pointed rod discharged electrical energy from heavily charged passing clouds that would cause Franklin's set of Gordon's Bells to ring.

WC Tesla coil revise

The WC coil went through numerous changes. The primary had to be changed after the secondary was replaced. I replaced the spark gap after many failed attempts at making the rotary gap work properly. The new static gap works wonderfully. Such is the life of a Tesla coil.

OMG we are going on vacation.

My lovely Green Butterfly and I are going on a cruise Feb 12 for 12 days. We are booked on the Azamara Journey

and I cant believe we are going here.

Day 1	Miami, Florida
Day 2	At Sea
Day 3	At Sea
Day 4	St. John, U.S.Virgin Islands
Day 5	Gustavia, St. Barts
Day 6	Fort De France, Martinique
Day 7	Bequia, The Grenadines
Day 8	Roseau, Dominica
Day 9	Basseterre, St. Kitts
Day 10	Virgin Gorda, B.V.I.
Day 11	At Sea
Day 12	At Sea
Day 13	Miami, Florida

I'm awake I know I am. Oh Hissy this is going to be a dream with you.

AAAAaaaaHHHHHhhhhh!

Control we have a problem.

This control box which I used to control power to my larger coils suffered a catastrophic failure a few weeks ago while running my six inch coil being powered by a NST stack of 3 x 15kV 30mA. I don't think it was the power I think it was a short due to the tight confines in which I placed all of the electronics in this box. I have always felt things were a bit tight but never could find reason to change it seeing that it has proven good in hard service for over 3 years. So I'm working on a new control box that will address all the possible issues I saw in the previous one. RIP