Monthly Archives: September 2014

Test Steps

To test the project, follow these steps:

1. Him R3 to full counterclockwise (CCW) and SI off. Insert a temporary 10-amp fuse into the holder.

2. Connect a test lead at the chassis ground and place the other end about one inch from the output lead of Tl. This is a crucial step.

3. Connect to a suitable 12-volt converter or a high-current battery. It is a good idea to moni­tor the input amps for circuit performance verification.

4. Turn the power switch SI on and note a quies­cent current of 1 amp. Slowly adjust R3 clock­wise and note a rise in the current of about 2 amps along with some corona at the output terminal. This is the low-output mode and can be used for continuous operation without overheating. Preset R4 to midrange.

Plasma arc starts at bottom of ladder and travels up the ladder elements where it expands and eventually extinguishes. Arc quickly reforms at the bottom and repeats itself.

Adjust bottom of ladder spacing so that arc reliability starts but yet does not remejn stationary Adjust top of ladder so that arc travels up to desired length before extinguishes and repeats It may lake patience and perseverance to get it right*!

1 Shape two 1/8" brass rods as shown.



Test Steps

2 Drill two 1/8" holes about 1/2" deep into EN1 enclosure as shown

3 Connect output lead of T1 to one rod andgroundleadtoother Solder or crimp for a positive secure connection.

4 Adjust bottom separation to 1/2". Separation between rods increases to about 1 to 2" at top end

Figure 17-B Final view of Jacob’s ladder project

5. Continue tuning R3 and note a very sharp rise in the current (about 7 amps) with the output coming to life. Immediately shut it down as the coil can be damaged in this mode without a suitable load such as connection to a neon or fluorescent tube.

lf you have a scope, you may short the output of Tl to ground and note the test patterns included in Figure 17-2. This verifies the oper­ation. Note that the transformer is designed to allow proper switching of ihe MOSFETs even with shoried outpui.

6. Replace the 10-amp fuse with a 5- to 7-amp value.

7. Insert a four-inch enclosure tube (EN1) into the boitom cap (CAP1). Use PVC plumber cement to seal these pieces as they must not leak the transformer oil. Do this only after

correct circuit performance has been verified as you cannoi service Tl without hacksawing the enclosure apart.

8. Fill the enclosure with oil to the lop of the Tl. It is not necessary to seal the top cap if the unit is always operated in its upright position. Note this step is not necessary for use wilh the enclosed experiments when operaied as shown.

9 Proceed to conduct the experiments as shown in figures 17-8 and 17-9. Experiment using pieces of steel wool, needles, and fluoresceni and gas-filled lamps, and observe how differ­ent materials react to the high-frequency energy. Caution: Obtain some potassium nitrate and sprinkle ii omo some steel wool. Note the pyroiechnic display. Danger: Do not use chlorates or perchlorates.

1. Carefully solder a piece of thin bus wire to the center terminal of lightbulb. This is usually iead and solders easily Caution lo not overheat.

2 Connect output lead from 11 lo this lead Bulb should be secured to top of EN1 via a small bracket or other suitable means. Use a nonconductive material

3. Use a 5", clear 100-watt "DECOR” lamp, preferably one made by Sylvenia orGE as these seem to work the best Experimant with other bulbs as you may get some interesting results

4 Do not leave this display on for long penods as high – frequency energy mey quickly puncture the thin glass envelope of these bulbs.

Figure 17-9 A poor man’s plasma globe

Table 17-1 Solid-state Tesla coil

Ref. # Qty. Description DB#

Rl, 6,7 3 10-ohm, ‘A-watt resistor (br-blk-blk)

R2 I -kilo-ohm, ‘/4-watt resistor (br-blk-red)

R3 5 kilo-ohm trimpot

R9 IO-ohm. ‘/г-watt resistor (br-blk-blk)

R8 15-ohm, 3-watt resistor (br-grn-blk)

R30 10K, 17-millimeter potentiometer

Cl 100 mfd. 25-volt vertical electrolytic capacitor

C2 4700 pfd, 50-volt polyester capacitor

C3 1000 m fd, 25-volt vertical electrolytic capacitor

C4 .1 mfd, 100-volt polyester capacitor

C5 .0033 mfd. 250-volt polypropylene capacitor

11 I ntegrated circuit driver 3525

Ql,2 2 MOSFETs IRF540

Tl Reworked flyback transformer; see Figure 17-3 FLYGRA

WR1BLK 6 feet #20 vinyl hookup wire, black


‘table 17-1 Continued

Ref. #




6 feel

#20 vinyl hookup wire, red


6 feet

#20 vinyl hookup wire, green


6 inches

#20 bus wire


PCB or perforated circuit board.1 X.1 grid



6-32 X ‘/z-inch nylon screws



6-32 X ‘/2-inch steel screws



6-32 nuts



Mica washers for Ql and Q2



6-inch nylon tie wraps


Fuse holder and 5-7 amp fuse


SPST 5-amp switch



#6 solder lugs


3/8-ineh plastic bushing


Strain relief plastic bushing


Mounting bracket, as shown in figure 17-4


Plastic channel base, as shown in Figure 17-5


2- X 2-inch thin plastic insulating sheet


3 ‘/2-inch plastic cap


4- X 3 l/2-inch schedule 40 PVC lube


Plastic cover, as shown in Figure 17-5


I – X ‘/«-inch vinyl tube for control pot, which prevents annoying burns


12-volt, 5- to 7-amp converter for main power


An advanced electrical project is an excellent display for museums or can be a fascinating and rewarding project for the serious and experienced hobbyist. Highly energetic audible and visual bolts of lightning jump into empty space, providing a spectacular effect. This can be an excellent advertising and attention-get­ting display when properly set up (see Figure 18-1).

The project is shown using basic materials but will require certain specialized parts readily available through our web site at www. amazingl. com (see Table 18-1). Expect lo spend around $400 for the spe­cial parts with the others available at a local hard­ware store. The unit utilizes dangerous high voltages and is not recommended for inexperienced person­nel. Safety is fully emphasized throughout these con­struction plans.

Circuit Theory

The output is a result of a resonating action of the secondary coil occurring around 50 to 70 kHz. Under these “tuned” conditions, the transformer requires considerable power and produces high-voltage dis­charges that would quickly break down the insulation if left on for any period of time. Immersion in an oil bath can help limit overheating and eventual break­down. but is not necessary if operated as directed.

Circuit Theory

Figure 17-2 Circuit schematic

Figure 17-2 shows the primary transformer Tl being driven by two metal-oxide-semiconductor field effect transistors (MOSFETs), Ql and Q2. in a push – pull configuration. This approach utilizes the full core potential of the flyback and reduces the electrical strain on the MOSFETs as they run very cool, even at 5 to 7 amps input. A driver circuit (11) generates complementary outputs 180 degrees out of phase
with built-in dead time. The frequency is made vari­able by control pot R30 and range-adjust trimpot R3. This adjustment allows a wide range of frequency, driving Tl out of the resonant mode where it can power a voltage multiplier and make a variable high – voltage DC source.

Capacitor C2 and R3 determine the operating fre­quency. Resistor R2 sets the upper frequency limit, and resistor Rl sets the switching dead time for reli­able operation. Resistor R9 and capacitor Cl provide decoupling between the MOSFETs and driver II. Resistors R6 and R7 eliminate parasitic oscillation from occurring on the gates of Ql and Q2. Resistors R8 and C5 form a snubber network to clamp the volt­age spike generated by the leakage inductance of Tl. The capacitance of the snubber absorbs the current charge of the spike, limiting the voltage peak to a safe level. The MOSFETs would quickly break down as a result of high-voltage spikes if it were not for this net­work. C3 and C4 bypass any of the high frequencies, appearing at the primary center point of Tl.

The power requirement for the unit is 12 to 14 volts-direct current (VDC) at a maximum of 5 to 7 amps when tuned to the resonant frequency of Tl. It is suggested that the entire Tl flyback assembly be immersed in transformer oil if full output operation is anticipated over a period of time. The oil bath both cools and provides added insulation to the high volt­ages developed, but is not necessary for normal oper­ation.


To begin the project, follow these steps:

1. Lay out and identify all the parts and pieces, and check them against the parts list.

2. Assemble Tl, the ferrite transformer, in Fig­ure 17-3. Measure the inductance if you have an LCR (inductance, capacity, resistance) meter for verifying the values given.

Circuit TheoryDue to the difficulty in reworking certain flyback Iransformers this ready-to-use part is available on www amazingl com Fortunately some units are easy lo disassemble while others are not.

1. Remove the "U" bolt and one of the core halves. Some units may require chipping away the binding material with a pointed object until fhe cores will come apart using moderete force.

2. Form a bobbin from a piece of plastic or cardboard tubing, as shown, of a length that allows core pieces to touch one another

3. Bifilarly (parallel) wind two different color #18 magnet wires for 10 turns of these double windings, leaving 8" leads. Note the different colors will help identify the lead ends.

4. Scotch tape the face of each core half so that when reassembled there will be two pieces separating each side of the cores. These should produce a 5 mil gap at each junction.

5. Place the coil wound in step 3 onto the cores as shown and tapa tightly into place.

6. Identify the secondary lead return that will be the leads attached to the base. Usually any one will work but it is suggested to use an ohmmeter and use the highest resistive combination Carefully attach an external wire to this point and strein relieve with some silicon rubber Verify other leads are not shorted together

You may verify the inductance as follows secondary open: A to B&C are around 15 microhenries.

Dto B&C are around 15 microhenries


Note that most flybecks are similar and will work Some may have a built-in diode in the output lead section of ihe secondary coil. This can be removed if the potting material is rubber; if epoxy "good luck"! Get a replacement.





This lead is ground return of outpul lead and is usually around 300 ohms. Attempt to use highest reading combination with output lead.

#18 solid magnet wire can be used; however, high-frequency LITZ wire will give a slight improvement. You can make this wire by obtaining 6 pieces of #26 magnet wire and twist together as a single wire.

Figure 17-3 Flyback rework for Tl

Fabricate the MTGBKT mounting bracket (see Figure 17-4) and the channel/cover com­bination as shown in Figure 17-5.

Assemble the board as shown in Figure 17-6.

a. Insert capacitors Cl and C3, and note the polarity, as these are electrolytic.

h. Insert C2, C4, and C5.

c. Insert RI, R2, R5, R6,R7,and R8. Note that the exposed lead of R8 should attach to Ql for an easy access test point.

d. Insert Ql, Q2, and T1, noting the polarity.

e. Solder in the remaining components and clip off the excess leads.

5. Mount the components tn the chassis bracket MTGBKT. Wire the assembled board to the

Circuit Theory


Holes shown are postered without dingn$kms to allow tor use e! alternate components tjien thoae shown Trial tit before drllHnj holes.

Circuit Theory


Figure 17-4

Mounting bracket fabrication


Circuit Theory

Side view showing У, а holes for securing cc

Figure 17-5

Fabrication of plastic channel and cover

Circuit Theory

Figure 17-Б Assembly board and external wiring

mounted parts and the primary leads of Tl, as shown in Figure 17-6 and Figure 17-7, using the appropriate lengths of the #20 vinyl hookup wire. Note the mounting scheme of Ql and Q2, as they must be insulated from the chassis bracket. Assemble this to the chan­nel via two 6-32 X Чг screws and nuts

SW2/NU1. Note the thin piece of plastic insu­lating material for the PC board.

Circuit Theory

Figure 17-7 Isometric view of the total assembly

6. Mount a 3.5-inch plastic cap, CAP2, to the channel using two screws, nuts, and small, flat washers SW2/NU1/WA1. Note the four holes for the two tie wraps to secure Tl in place via
the primary section shown in Figure 17-7.

Note the ground return lead of Tl being routed through a small hole beneath the chan­nel and returning through another hole to connect to common ground point.

7. Finally, assemble everything as shown and insert a 4- X 3’/2-inch polyvinyl chloride (PVC) tube (EN1), as shown in Figure 17-8.

8. Verify all wiring with the schematic. Use an ohmmeter to check that the drain tabs of Ql and Q2 are insulated from the metal chassis. Check for solder joints, shorts, and so on.

9. If you decide you require oil filling, CAP2 will need to be replaced with an actual PVC flat cap fitting, intended for a З-inch (actually 3.5- inch OD) schedule 40 PVC tube. These parts are available through most local hardware stores. Add a sealant using PVC cement and primer as directed on the container. Note that the oil filling is only needed for light loads where the output voltage will be excessively high.

Experiments and Applications Using Ions

• Ion high speed motor Spin a metal rotor into the thousands of RPM (see Figure 16-1 and 16-10).

• Force field Forces an object on to a surface with considerable pressure (see Figure 16-10).

• Motion freezing Capture high-speed peri­odic motion as a moment in time (see Figure


• Charge transmission and capacitor charging

Charge objects to high voltages without con­tact (see Figure 16-10).

• Negative ion generator and ion wind Pro­duce a high flux of beneficial negative ions. Easily detectable (see Figure 16-10).

Experiments and Applications Using Ions

The ground lead is not necessary for proper operation of this project

Figure 16-7 Set up for deodorizing machine

Experiments and Applications Using Ions

Experiments and Applications Using Ions

Figure 16-B Magic electric man

Caution This project can produce painful and annoying shocks if improperly used It should only be attempted by those experienced in use of HV for magic shows props, etc

Instructions – Grab a fluorescent or neon tube In one hand end with the other tightly hold a metal object at least 1" in diameter by Є to 8 in. in length, (touching as much surface area as possible with your hand). Turn the unit on end contact the HV output with the metal object, noting the lamp in your other hand energizing, indicating an electric current flowthrough your body without any shock" Bnng the lamp near з large metal object or another person and note it getting brighter This experiment affects the skin where high-frequency currents flow on the surface otlhe person’s body lighting the tamp and the capaatwe properties of conductive objects w+iere they seemingly attract electrical energy

Power to this unit car be any 12to 14 VDC воіасе capable of supplying 1 amp. The ground lead must be grounded far proper operation

Use a plasma arc to burn in etches and designs Into nonconductive materials such as wood plastic, etc. (THIN WOOD WORKS EXCELLENT) This effect is very similar to the old wood-burning sets but can produce much finer and precise designs once mastered

Burn must be prestarted with en existing arc drawn from в grounded point to start the carbon channel We attach the ground return wire to a thumbtack Once the arc trace is started, it can be continued as desired Our lab samples were done or a 1/4" piece of mason slightly dampened

Figure I6-9 Plasma etching

This setup cen also be used for Killian Photography projects. Experimenters may wish to consider our available #KIRL1 plans

Experiments and Applications Using Ions

amp The ground lead must be connected to a smell pin or thumbtack inserted into the object at the intended beginning of the plasma design

Experiments and Applications Using Ions

discharge probe

Figure ІБ ID Magnifier retrofit

Table 16-1 Complete parts list for your Tesla plasma and ion generator

Fief. #





120 ohms, L watt (br-red-hr)


1.5K, >/* watt (br-grn-red); see note on schematic


1000 mfd/25-volts electrolytic vertical capacitor


.1 mfd/50-volts plastic capacitor


.068 mfd/50-volts plastic capacitor


1 ml’d/250-volts metallized plastic capacitor


.047 mfd/100-voIts plastic capacitor



25 pfd at 6 Kv ceramic capacitor


MJE3055t T0220 power lab NPN transistor


Special high-voltage, high-frequency transformer



48 inches

#20 vinyl wire


16 inches

#14 straight US wire or ‘/if. – inch brass rod for ladder elements in Jacob’s ladder


PCB or use a piece of 3 ’/2 – X L Чг – inch.1 grid perf board



3X3 .063 Al plate with folded corners fabricated as shown


-Vn-inch plastic bushing


3/«- X 6-inch length of plastic tubing for safety probe and plasma pen


3- X 1 V-j-inch.063 plaslic bracket



6-32 3A Phillips screw


#6 X 3/s-inch Phillips sheet metal screw


6-32 X l/2-inch nylon screw



6-32 kep nut


Mica washer for TO 220 transistor


10 X 1 Vj OD x 1 ‘/]<. wall, clear CAB plaslic tubing


4-inch tie wrap


Small wire nuts


14 volt, I amp with internal ground



Small neon lamp with leads


15-incb length of colorful neon in green, red. blue, purple, white



12 inches

Hexihle silicon 20 Kv wire

CM 1-8


500 Ptd/I() Kv ceramic disk capacitors

500/10 Kv



10 Kv. 5-milliampere, 100 ns high-voltage rectifiers



220 ‘/2-watt resistor (red-red-br)


47K, 1-watt resistor (yel-pur-or)


4 ‘/< X 1 ‘A.1 x. I grid perforated circuit vecior hoard

Table 16-1 Continued

Hef. # Qty. Description DB#

RGTOR Ion-propelled, four-poim aluminum roior ROTOR

BALL38 Small brass ball with threaded hole

Miscellaneous hardiuare Small needle for ion motors Piece of masonite for plasma writer

6 to 8- x 1 !/2-inch piece of metal tube or rod for electric man experiment Miscellaneous wire, hardware, and so on

This versatile project shows how to convert a readily available television flyback transformer into a high – frequency. high-voltage generator operating from 12 volts or a battery source (see Figure 17-1). The assembled device is excellent for powering all kinds of gas display pieces from plasma balls to an every­day lightbulb. Chapter 20, "Amazing Plasma Tornado Generator,” shows how to actually build a plasma tornado with some fascinating and unique properties. The solid-state Tesla coil can be used to create ozone, corona and brush discharges, and electric pyrotech­nics, including a small Jacob’s ladder.

Experiments and Applications Using Ions

Figure 17-1 Solid-state Tesla coil

The construction here includes an easy-to-build circuit costing under $50 with parts readily available. Those that are special, such as a printed circuit board (PCB), may be obtained through www. amazingl. com. Flyback will require some re­work involving disassembly and the addition of a 10- lum coil. Some small hand and soldering tools are required. The necessary parts are listed in Table 17-1.


Tb test the circuit out, temporarily and quickly con­nect a 12 VDC source of 1 amp to the input power leads, and note a current draw of around.3 to.5 amps. Touch the output lead with an insulated metal tool and note a small arc of [3]U to Чг inches. Do not operate for more than several seconds as Ql will overheat because it requires mounting to the base section for heat sinking. You may want to verify the wave shape on the collector of Ql, using a scope. It should resemble that shown in Figure 16-2.

Mechanical Rssembly

Assembling the parts is done by following these steps:

everything before actually drilling. Fold down the corner sections of the base to form the legs as shown in Figure 16-4.

2. Fabricate the bracket BK1 from a piece of formable plastic that is З X 1 V« X.063 inches. Fold a ‘/2-inch lip for mounting to the base section. Note the clearance hole for SW2. Position as shown, abutting to the rear of the assembly board. This will provide a stable mounting scheme.

3. Finally, assemble as shown in Figure 16-4. Secure the assembly board to the bracket using a plastic tie wrap. Ground the base sec­tion with a short piece of bus wire under SW2 and attach the wire to the P2 line on the board.

4. Fabricate the shroud tube from a piece of clear 10- X 174-inch OD plastic tubing. This piece slips over the assembly and provides enclosure protection while allowing visibility of the circuitry. This is an obvious asset when making a science project presentation. Note you will have to file slots or grooves at the bottom to allow airflow and to clear screw SW2.

Test and Function Selection

From Fig. 16-3


grounding screw Figure 1Б-Ч Mechanical assembly

Connect a 12 to 14 VDC source of 1 to 2 amps, and test it by touching the output with the end of a fluo­rescent tube, noting a moderate bright glowing. Study the following data to decidc the experiments you wish to pursue. The unit can be operated from any 12- to 14-volt battery pack that can supply a current of 1 to 2 amps or more.

It is important, where noted, that the unit be earth grounded with a separate grounding connection to a known, grounded object. A wall adapter, when used, will require a separate grounding wire for proper operation as the output circuitry is usually isolated

from the primary plug side, as there is no third wire grounding pin. The screw of a receptacle plate can be used for this external connection, as is noted on the drawings. When using a converter, automatic ground­ing is usually via ihe third prong on the power plug, which is the same as the negative lead output (see Figure 16-4). Experimenting with ions will require assembly of the magnifier retrofit as shown in Figure 16-10.

Experiments and Applications Using Plasma

• Radiated power Energize a light without

any connections (sec Figure 16-5).

Radiated Power Project

Clear plastic should be removed for access io output It is necessary to prevent accidental contact that can cause annoying but not dangerous shocks.

Shape a 10" length of #14 bus lead or 1/16" brass rod and shape as shown wilh a loop lo fit around the screw for securing in place. This serves as a small energy radiator.

Obtain a gas discharge lamp such as a piece of neon or use the test neon lamp in the kit and, holding one of Ihe leads, bring it near ihe radiator, noling rt glowing up to a foot or so from the unit. Try with a larger fluorescent tube

Gas Tube Energy Supply

Touch one end of a household fluorescent tube to the output radiator and note lamp glowing wilh only the single connection. This demonstrates the high – frequency ground current flowing via the electrical capacity of the discharge tube.

Pyrotech Display

Obtain some steel wool and attach a small tuft to the oulput lead. Draw an arc with a grounded object and note strands brightly burning. Experienced personnel may wish to add certain oxidizing chemicals to greaily enhance this effect USE CAUTION.

– Air circulation gap


Copyright 10/97

Connect this lead to Ihe socket plata screw of Ihe AC receptacle.

Fi g и re 16-5 Set up for radiated power

The ground lead is necessary for proper operalion of this project as capecitive ground currents are produced.


Figure 16- б Jacob’s ladder project

Gas discharge power supply Energize color­ful neon and other gas-filled tubes (see Figure 16-5).

Electrical pyrotechnic display Burn up a piece of steel wool in a shower of sparks (see Figure 16-5).

Jacob’s ladder Build the popular traveling plasma arc machine seen in Frankenstein movies (see Figure 16-6).

Build au effective deodorizing machine It

actually produces fresh air (see Figure 16-7).

Magic electric man Energize a fluorescent tube by the touch of your hand (see Figure 16-8).

Plasma etching Use an electrical arc to cre­ate intricate designs in wood and plastic (see Figure 16-9).

Experiments and Applications Using Plasma

Circuit Theory

Figure 16- 2 shows transistor Ql connected as a free – running flyback oscillator with a resonant frequency determined by capacitor CX and the short-circuil pri­mary inductance (LP) of transformer Tl. The leakage inductance of Tl must be high as it is where the inductive energy is stored when Ql is biased on. The current now ramps up as a function of і = ET/L. Energy is equal to W = Li2/2.

Circuit operation commences when 12 VDC is applied and resistor R2 biases Ql on, and the current now flows through the primary of Tl, inducing a high voltage into the secondary winding. Oscillation is maintained by the base of Ql being controlled by the feedback voltage from the feedback winding on Tl. The feedback current is limiled by resistor R2. Capacitor CX aids in speeding up ihe turnoff time of Ql. Resislor R3 and capacitor C5 form a filter to pre­vent self-oscillation at the resonant frequency of the secondary ofTl.


To begin the project, follow ihese steps:

1. Lay out and identify all the parts and pieces. Verify them with the parts list, and separate the resistors as they have a color code to determine their value. Colors are noted on the parts list.

2. Obtain the available PCB as shown in Figure 16-3 or fabricate a piece ol perforated circuit board (perf) to match the PCB (PC) as laid

Experiments and Applications Using Plasma

Experiments and Applications Using Plasma

drawing as these indicate connection runs on the underside of the assembly board.

4. Attach three 6-inch #22-20 leads as shown for input power (Pi and P2) and external ground­ing. Attach a short piece of bus wire for grounding of the base section. Leads are routed through the BUI bushing and are twisted in the final assembly steps. Attach pieces of bus wire to the output connections (P3 and P4) and shape them to fit around the screws as shown.

5. Double-check the accuracy of the wiring and the quality of the solder joints. Avoid wire bridges, shorts, and any close proximity to other circuit components. If a wire bridge is necessary, sleeve some insulation onto the lead to avoid any potential shorts.

out. Note that the size of the PC board is 34i – x P/e-inches and contains the silk screening that shows the positioning of the mounted parts. Note that the Ql transistor must be mounted so that it is flush with its mounting surface at a right angle. This step is important for proper heat sinking and mechanically sta­bility.

3. If you are building from a perforated board, insert components starting in the lower left – hand corner. Pay attention to the polarity of the capacitors with polarity signs, as well as all the semiconductors.

Route the leads of the components as shown and solder as you go, cutting away unused wires. Attempt to use certain leads as the wire runs. Follow the dashed lines on the assembly

Figure 16- 2 Tesla plasma and ion schematic

Experiments and Applications Using Plasma

Note thal C6,7 are in в different location than that indicated by the screening on the printed circuit board

Fi g и re 16-3 Assembly board showing part identification