Construction Steps

Here you’ll begin construction of the electronic ion – generating power supply. The ion generator is shown built using a perforated circuit board, as this is the preferred approach for science projects because the system looks more homemade.

The perforated board approach is more challeng­ing. as the component leads must be routed and used as the conductive metal traces. We suggest that you closely follow the figures in this section and mark the actual holes with a pen before inserting the parts. Start from a corner, using it a reference, and proceed from left to right.

The printed circuit board (PCB) only requires that you identify the particular part and insert it into the respective marked holes. Soldering is now greatly simplified.

1. I ay 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 as noted.

2. Cut a piece of. 1 – inch grid perforated board to a size of 4.8 x 2.9 inches. Then cut a piece of 10- X 2.9- X.063-inch polycarbonate for the multiplier section. Locate and drill the holes as shown in Figure 22-3. An optional PCB is available from Information Unlimited.

3. Fabricate the metal heatsink for Ql from a piece of.063 aluminum at 1.5 x.75 inches, as shown in Figure 22-4.

4. Assemble LI as shown in Figure 22-4.

5. If you are building from a perforated board, insert components starting in the lower left – hand corner, as shown in Figure 22-5 and 22-6. Pay attention to the polarity of the capacitors with polarity signs and to 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

Construction Steps

PERFBDARD

POLYBOARE

The assembly board is in two sections attached together by two outer 6-32 nylon screws and nuts. The middle hole is used to fasten the entire assembly to the base of the enclosure.

The circuit section is 4 8" x 2 9" x.1" perforated board. The high voltage polycarbonate section as shown is 10" x 2 9” x 063" thickness This is sufficient to accommodate 10 stages of multiplication Drill 063" holes in the perforated section and the polycarbonate section located as shown

Drill the three 125" holes in both sections far attaching together

Drill and drag the.125" slot as shown. This cutout and the enlarged holes are for mounting transformer T1 Using the optionally available printed circuit board will still require fabrication olthe Plexiglas board.

Hole diameters are not critical.

Always use the lower left – hand corner of the perf board for position reference.

Figure 22 3 Driver and multiplier board fabrication

Construction Steps

Figure 22-4 LI current feed inductor and heatsink bracket

Construction Steps

wire runs or use picces of llie included #22 bus wire. Follow the clashed lines on the assembly drawing as these indicate connection runs on the underside of the assembly board. The heavy dashed lines indicate use of thicker #20 bus wire, as this is a high-current discharge path and common ground connection.

6. Attach the external leads as shown in Figure

22- 6. Figures 22-7a and 22-7b arc enlarged views of the assembly board wiring.

7 Assemble the voltage multiplier as shown in Figure 22-5. The projcci shows 10 stages of voltage multiplication. Each stage consists of two capacitors (C20xx) and two diodes (D20xx).The stages can be reduced to a num­ber of 10 where you will obtain 7 to 10 Kv of output as each stage contributes this amount of additional voltage. Additional stages over 10 will produce more ions but will only gener­ate a higher potential when terminated into a smooth 4- to 5-inch terminal.

8. Double-check the accuracy of the wiring and the quality of the solder joints. Avoid wire

bridges, shorts, and close proximity to other cir­cuit components. If a wire bridge is necessary, sleeve some insulation onto the lead to avoid any potential shorts. See the note in Figure 22-5 showing smooth, globular solder joints for all high-voltage points on the multiplier board.

Testing Steps

Го run a test on your device, follow these steps:

1. Preset trimpot R1 to midrange and R10 to full clockwise (CW).

2. Obtain a 25-megohm, 20-watt high-voltage resistor. You can make this part by connecting 25 1 – megohm, 1-watt resistors in a series and sleeving them into a plastic tube. Then seal the ends with silicon rubber

3. Obtain a 12-volt, DC, 3-amp power converter or a 12-volt battery. You may use the 8 A A cells in the specified holder.

See Figures 22-7a and 22-7b and В for enlarged views of this figure

Thick dashed lines are direct connection runs beneath board of #20 bus wire (WR20BUSS) and are extended for the spark switch electrodes

. Thinner deshed lines are #24 bus wire (WR24BUSS) and component lesds wherever possible.

Tnangles are direct connection point junctions

, Solid black lines are external leads for input and output lines Use red (WR20R) for +12 input Use green (WR20G) for lifter connection Use black (WR20B) for com -12 input

Construction Steps

Figure 22-Б Wiring connections and external leads

Construction Steps

Figure 22-7Я Enlarged view of the assembly board

Construction Steps

Figure 22-7B Enlarged view of the high-voltage section of the assembly board

Construction Steps

Front view showing handle and bracket

Figure 22-8 X-ray view on circuit innards

4. Connect the input to the power converter and the midsection of the multiplier section to the 25-megohm load resistor. Connect oscillo­scope to drain pin of Q1 and set it to read 100 volts with a sweep time of 5 microseconds (usees).

5. Apply power and quickly adjust Rl to the wave shape shown in Figure 22-2. The spark gap may fire intermittently and should be respaced just lo the point of triggering. This is usually between 25 to 30 Kv.

6. Rotate RIO counterclockwise (CCW) and the input current smoothly drops almost to zero. This control varies the ratio of off to on time and nicely controls the system current to the ion emitters.

If you have access to a high-voltage probe meter, such as a B&K H V44, it will be possible to measure the direct output, noting 20 to 30 Kv across the 25- meg load resistor. This equates to over 30 watts! You will see a smooth change in output as R10 is varied.

Also note that the output voltage indicates only half the output value and is also heavily loaded by the load resistor along with the rest of the system. In actual usage in the intended ion and chargc gun. the input current will be adjusted low by the setting ol R10 as excessive power is not necessary.

Also, do not continually allow a hard spark dis­charge as circuit damage can occur.

Circuit Operation

Your ion ray gun requires a high DC voltage at a very low current. The driver power supply, as shown in Figure 22-2, generates over 600 micro-coulombs (600 micro-amps per second).This amount is a large num­ber of ions and is sufficient to induce shocks at a dis­tance, charge objects, and perform a host of bizarre electrical experiments. Even though the current is low, improper contact can result in a harmless yet painful shock.

The output voltage of the driver is obtained using a Cockcroft Walton voltage multiplier with 4 to 10 stages of multiplication. This method of obtaining high voltages was used in the first atom smasher ush­ering in the nuclear age. The multiplier section requires a high-voltage/frequency source for input supplied by transformer Tl, producing 6 to 8 Kv at approximately 30 kHz. You will note that this trans­former is a proprietary design owned by Information Unlimited. The part is small and lightweight for the power produced.

The primary winding of Tl is current driven through inductor LI and is switched at the desired frequency by field-effect transistor (FET) switch Ql. Capacitor C6 is resonated with the primary of Tl and zero-voltage switches when the frequency is properly adjusted. (This mode of operation is very similar to class E operation.) The timing of the drive pulses to Ql is therefore critical to obtain optimum operation.

The drive pulses are generated by a 555 timer cir­cuit (II) connected as an astable multivibrator with a repetition rate determined by the setting of trimpot (Rl) and a fixed-value timing capacitor (C2). II is now turned on and off by a second timer, 12. This timer operates at a fixed frequency of 100 Hz but has an adjustable ‘’duty cycle” (ratio of on to off time) determined by the setting of control pot RIO. II is now gated on and off with this controlled pulse, pro­viding an adjustment of output power.

Even though the output is short circuit protected against a continuous overload, constant hard discharg­ing of the output can cause damage and must be lim­ited. A pulse current resistor, R7, helps to protect the circuit from these potential damaging current spikes.

Figure 22-2 Ion rav gun schematic

Circuit Operation

r

!

I Output should be terminated into a 25- megohm, 25-watt, high-voltage resistor і for load test Conned scope to test point TPX Adjust Rt to the wave shape shown with unit connected to a 12-voH. 3- amp supply

Output voltage should be 30 Kv, indicating a current of over 1 ma Input current will be 2 5 amps with a power output in excess of 30 watts1

Power input “enable” is controlled by switch SI that is part of control pot RIO. A trigger switch (PBl) ВОЭГС) RSSEITlbly StEPS

allows instantaneous control. The actual power is a

battery pack placed in the handle that consists of 8 To assemble the perforated circuii board, follow

AA cells in a suitable holder. A virtual ground is pro – these steps:

duced by user contact to the circuit return via a

metallic probe built into the handle.

Ion Ray and ilharge Gun

Ion Ray and ilharge Gun

Figure 22-1 Ion ray gun

This project shows how to build a device that pro­duces a bizarre yet interesting clcctrical phenomena that possibly may provide the propulsive forces used for space travel in the near future. A high potential source is allowed to leak off charges by being termi­nated into a sharp and pointed object. A charge emis­sion now occurs due to the repulsive force of like charges occuring at the pointed end. producing a high density of charged particles that possess mobility over a distance. The finished unit is intended for use

by the electrical physicist (see Figure 22-1) as well as for educational demonstrations, material testing, and many other applications as presented in this chapter.

Expcct to spend $75 to $100 for this useful electri­cal device. Assembly will require only basic hand tools, wiring, and soldering. The finished project must be used with caution as moderate electrical charges can be generated at a distance. The parts list for this project is shown in Table 22-1.

Test Paints and Troubleshooting Suggestions

The following are some measurements for testing the device:

• Measure 9 VDC at the TPA point and at the COM line. If ihe previous tests cannot be obtained, it is suggested to double-check all

wiring and components for correct placement. Pay attention to Ql and Q2, as they are not the same.

■ Measure 0 VDC at the TPB point and at the COM line.

• Short contact probes A and В together and now measure 8 to 9 VDC at TPB.

• If the display tube fails to ignite, double-check all the wiring and components for correct placement. Pay attention to Ql and Q2, as they are not the same.

Special Notes

Gas tubes longer than 30 inches may require a 12- volt battery pack to activate to full length.

The electronics assembly and batteries will easily fit into the often preferred Graphlex and Heiland camera flash handles. Contact the factory for facsimi­les of this hard-to-find part.

This chapter’s plans show the unit built with a 26- inch gas display tube. The system is designed to use any length of tube up to 36 inches long. The only modifications will be the length of the outer shroud tube and adding or subtracting the spacer rings. Our standard lengths of tubes are 12,26, and 36 inches.

The touch probes may be replaced by a 1 megohm adjustable pot and switch for varying the discharge length. R1 must be changed to a 47-kilo-ohm value.

Batteries

The unit will work with two alkaline batteries con­nected in parallel to double the current rating for about five hours of “off and on” operation. Two lithium batteries, while more expensive, will allow eight hours of operation. The suggested nickel-cad- mium (NiCad) rechargeables are Varta #TR % for 9.8 volts. The running time for two batteries will be almost an hour before recharging.

Thirty-six-inch red neon units may require 12 volts, which is obtainable by using 8 A A cells to fully ignite the display. You may also use two AAA cells connected in a scries with the existing two 9-volt bat­teries. The wiring is shown in Figure 21-2. This approach allows fitting with the Graphlex and Hei­land handles, as were the original props. Double­check the heatsink tab for Q3.

Rpplications

The property of the moving, ignited plasma your lightsaber produces can be utilized to provide an indicator of direction, such as turn signals for vehi­cles, semaphore signaling, pointing devices, or an excellent safety device for nighttime jogging or walk­ing as a visible, piercing colored light is produced.

Table 21-1 Plasma lightsaber parts list

DB#

Hef # Qty. Description

Rl 5.6 meg, ‘/«-watt resistor (gr-b]-gr)

R2 IK, Vt-watt resistor (br-blk-red)

R3 2.2K, ‘A-watt resistor (red-red-red)

R4 4.7K, ‘/4-watt resistor (yel-pur-red)

R5 330-ohm, Vt-wati resistor (or-or-br)

Cl.01 mfd, 50-volt plastic capacitor

C2 10 mfd, 25-volt electrolytic capacitor

C3 .022 mfd, 250-volt plastic capacitor

C4 .1 mfd. 400-volt metal polypropylene capacitor

Ql PN2907 PNP GP transistor

Q2 PN2222 NPN CP transistor

Q3 MJE182 power tab NPN transistor

#28K077

#PCPFS5

Tl Ferrite high-voltage transformer

CL 1,2 2 Battery snap connectors

PCPFS5 PCB

HS1/SW1 Heatsink bracket and #6 X 1/4-inch sheet metal screw

BUSWIRE Three-inch piece of bus wire for connecting Tl pins

WR2 2 12-inch lengths of #24 vinyl hookup wire

ADPAPTER1NGS 3 1 Чг OD X ] hole X ’/it) Lexan washer fabrication

SHROUD 29 V2 xl OD X Vie wall Lexan or other clear or colored

plaslic tubing

SPACER 4 Vs X 3/n hole X ‘/s flexible, clear vinyl washer

CAP 1 1 -inch clear plastic cap

CAP2 1 Ve-inch black plastic cap with l-inch hole

CAP3 1 Vs-inch black plastic cap

PROBE 2 2-Х ‘/4-inch strips of adhesive, soldcrable, metallic tape

НЛ1 10 Чг – X 15/s-inch black plastic handle

INSERT 3/e – X 3/e-inch Tygon tubing

#NE26 available in “phaser" green, “photon” blue, *’starfire“ purple or “neon" red

NE26 26-inch x 10-millimeter special prepared plasma tube

Test Paints and Troubleshooting Suggestions

Mechanical Assembly Steps 3

To begin the project assembly, follow these steps:

1. Cut a 29 ‘/2-inch length of 1-inch OD plastic tube for the shroud, as shown in Figure 21-6.

Even up and remove sharp edges from the 4.

ends. A red transparent tube greatly enhances the display when using red neon gas.

2. Fabricate four flexible spacer rings from a ^ sheet of clear, flexible Va-inch vinyl, as shown

in Figure 21-6. These spacers position the neon tube, NE26, inside the plastic shroud and offer some shock protection in case the units

are mishandled. The center holes should be a snug fit to the neon with the outer diameter providing reasonable friction to the inner walb of the shroud tube. These spacer rings should be positioned on the NE26 display tube as shown. Note that other materials may be used for this part.

Fabricate three adapter rings as shown in Fig­ure 21-6. The outside diameter must fit snugly into handle HA1. A 1-inch hole must be in the true center and fit snugly around the shroud. These are positioned and glued to the shroud tube, as shown in Figure 21-5.

Fabricate CAP2 with a 1-inch center hole and position it on the shroud assembly as shown in Figure 21-5. It should abut closely to the for­ward adapter ring.

Fabricate handle HA1 from a 10-inch-long piece of 1 %- X ‘/іб-inch rigid, wall polyvinyl chloride (PVC) or an equivalent material. Place two, small ‘/it-inch holes as shown in Figure 21-5 for contact probe leads. Note that

ADAPTER Rings (3)

Note the project sHows a 24" plasma display blade You may use up lo a 36" display blade but must increase the shroud by an additional 12” and add 2 more spacers. All other components will support this option. All display plasma blades are available from www. amazingl .com

From Figure 21-3

A12" blade is available to make a plasma dagger

Figure 21-6 Assembly of display tube, shroud, and spacers

Mechanical Assembly Steps 3

Mechanical Assembly Steps 3

Figure 21-7 Plasma lighlxaher filial view

Ihe position is not critical and can be placed to suit your preference.

6. Insert the NE26 tube assembly (see Figure 21- 6) with spacer rings along with the assembly board into the shroud as shown. It may help to moisten the inner walls of the shroud by breathing into one end and quickly inserting the neon tube assembly. You may also use a mist bottle. Work gloves should be used to avoid injury in case ot breakage.

7. Insert the above assembly into handle HA1 with the forward adapter ring recessed into the handle approximately 4a of an inch (see Figure 21-5). You may glue it in place or leave it as is for disassembly. Slide CAP2 into place as shown. Please note that it may take consid­erable force as the fit is tight and will not nor­mally need gluing.

8. Using extreme patience and your own ingenu­ity. attempt to thread the probe wires through the holes in HA1, as shown in Figure 21-5. Sandwich the stripped ends to the handle with small pieces of metallic tape as shown. Note that electrical contact is made to the metallic probes by this sandwiching action. Cut the pads to shape for appearance using an x-acto knife.

9. Insert two fresh, standard У-volt alkaline or lithium batteries into CL1 and two battery snaps into the handle. Obtain some foam rub­ber and use some pieces to hold the batteries in place. Secure the end with the CAP3 cap. Test the unit by touching the probes and ver­ify that the correct operation occurs. Verify the heatsink is not too hot to touch.

10. Finally, assemble everything as shown (see Figure 21-7) by attaching the caps into place along with any labels or decals. Now go forth, have fun. and may the force be with you.