
Parts List
R1 = 3K3, 5%
R2 = 1M, 5%
C1 = 0.1µF, monolithic capacitor
C2-C9 = 0.01µF 400 volt polyester capacitors
D1-D8 = 1N4007, 1000 Volt diodes
Neon = Type NE-2 neon bulb
Q1 = MJE521 NPN power transistor (40V/40W/4A)
Q2 = MJE371 PNP power transistor (40V/40W/4A)
T1 = 1200:8 ohm audio output transformer (green), Armaco AT-49
S1 = SPST momentary-contact, pushbutton switch
Additionally:
9-volt
battery clip, 10 x 5 x 2.5cm plastic case, 7.5 x 4cm perfboard or pcboard, two
8/32 x 1-1/4 bolts and nuts for electrodes, adhesive for mounting NE1, circuit
board standoffs (optional), hookup wire, solder,
etc.
Substitutes:
Q1 (MJE521), the NTE184 or 2N5190 will
work, and for Q2 (MJE371) the NTE185 or 2N5193 will work. T1: Mode 60-282-0
(Audio) about $2.00, Armaco AT-49 (Audio) about $5.00, Hammond 141P (Audio)
about $19.00. I have not experimented with the 1000:8 ohm type. Try it. No
guarantees it will work. Why an audio output transformer? The windings are much
finer and the overall size of this transformer is much smaller than the average
power transformer. Compare it this way, holding a mini-cell phone versus a stone
brick. Again, and just in case you don't know, the Audio Transformer mentioned
for this project is measured in OHMS (impedance)
and not turns or windings.
WARNING: THIS DEVICE IS NOT A
TOY! We present it for EDUCATIONAL and EXPERIMENTAL purposes ONLY. The
circuit develops about 2000 volts at a respectable amperage. It can cause you
pain and even damage if you become careless and touch its output terminals. The
unit can also damage property as well so use it wisely. You should NEVER use the
device on another person! It may not be against the law to possess such a device
in your area, but if you use it on someone you may be deemed liable a a civil
and/or criminal action suit. Don't just follow the golden rule after
constructing the project, instead just don't do it unto anyone. Included in the
article are a number of instructions on how to build, test, and operate the
Dazer; all of them must be followed to the letter. Do not deviate from the
procedure.
The Electronic Dazer is a modern, portable,
non-lethal-personal-protection appliance. It generates high potential energy to
ward off vicious animals or other attackers. It is an aid to help escape from a
potentially dangerous situation. This device develops about 2000 volts. Higher
voltages may be attained by adding additional multiplier stages, but it should
be noted that those stage(s) will also increase the overall size of the
unit.
The Dazer is very compact, being built into a small plastic case. It is
powered by a single 9-volt Alkaline battery.
The high voltage is applied to
two electrodes which require only light contact to be effective. When touched
with the Dazer, the victim or animal will receive a stunning, but non-lethal
jolt of electricity that will usually discourage any further encounters.
The
electronic Dazer is a power supply which consists of a micro-size regenerative
amplifier/oscillator coupled to an energy multiplier section. It should not be
confused with cheap induction-type cattle prods. The Dazer is more versatile
than other high-voltage stun devices currently being sold. Those devices are
basically high-voltage, AC generators which jam the nervous system. However, the
Dazer may be used for heating and burning applications, or anywhere a high
voltage DC supply is required.
(Tony's Note: Don't confuse the
Dazer with a Stun-Gun. The Dazer emits high voltage about 2000V DC, a
Stun-Gun can generate VERY High Voltages varying from 15,000V to
650,000VAC (as claimed by some manufacturers), and can cause personal
injury or even death. Stun-Guns are considered banned illegal fire-arms, you
risk criminal prosecution if law enforcement finds one in your possession
(Canada, not sure about USA).
How it
Works:
Refering to the schematic diagram, the two power
transistors Q1 and Q2, form a regenerative amplifier operating as a power
oscillator. When Q1 turns on, Q2 turns on and that shorts the power supply
across the primary of T1. That current pulse induces a high voltage in the
secondary of T1. As C1 charges, Q1 turns on again and the cycle repeats itself.
Therefore, a rapid series of DC pulses are generated and stepped up by T1 to
approximately 300 volts at full battery charge. That voltage is rectified and
increased by the voltage multiplier section which consists of C2 to C9, and D1
to D8. The final output is approximately 1500-2000 volts. The neon bulb 'Neon'
is used as a charge indicator and indicates that the unit is charged and
operating properly, but can be left out.

Check out fig. 1 at the right; these are standard voltage
doublers found in many data books and others like the NTE, Newark, or
Electro-Sonic catalogs. They can even be found on the internet. Just do a search
on one of the major search engines like Yahoo or Google and search for 'voltage
doubler' or 'HV'.
Construction:
As with all projects start out by laying
out and identifying. If you do not wish to make a printed-circuit-board, then
you may use perf board as long as you remember to keep the leads of all
high-voltage components isolated. That is to prevent sparks from arcing across
your board. A 4 x 7.5 cm of perfboard is suitable for that purpose.
The first
components you should mount are the two transistors Q1, Q2, transformer T1,
resistor R1, and neon bulb 'Neon'. Solder them in place (for PCB construction)
being sure that the transformer and transistors are hooked up correctly. Apply a
small amount of adhesive to the base of NE1 to hold it securely in
place.
Mount D1 to D8 and C2 to C9 on the board and make all solder
connections. Note proper polarity of the diodes. The off-board components are
next. Solder in leads for S1, and the output electrodes. Also solder in the
battery clip for B1.
Build the enclosure from some nonconductive material
such as ABS plastic. Drill holes for S1, Neon, and output electrodes. Be sure
that the output electrodes are about a cm or greater apart. Connect the output
wires tot the electrodes and insert them trough holes from inside of the case.
Thread on the retaining nuts and tighten them securely. Set the circuit board in
the case and mount S1, securing with a nut. Coat the voltage doubler stages with
clear nail polish or varnish. File down ALL sharp points and edges to
prevent sparking at those points. That completes the
construction.
Testing:
Before inserting the
battery and closing the case, a few test measurements should be made
to ensure correct operation.
With the ground clip connected to the battery
(do NOT connect the complete clip to the battery ONLY the ground), connect a volt or multimeter between
the positive clip and the positive terminal of the battery. Set the meter for
current reading, and press S1. You should measure a current of approximately 300
to 500mA. The 'Neon' light should be glowing.
With a high voltage multimeter
or VOM, you should measure about 2000 volts on the output terminals. Those
measurements indicate proper circuit operation. Let the unit run for about one
minute (keep pressing S1). Transistors Q1 and Q2 should be warm, but not hot to
the touch (BE CAREFUL!). Insert the battery in the holder and close the
case. That wraps up the Electronic Dazer. (see pictures below)
Operation and
Use:
Activate
the unit by pressing S1. The Neon-bulb will light indicating the dazer is fully
charged and ready to use. Notice also that only one pole of the neon light will
glow, indicating DC voltage present. It is important to remember that the
device holds a charge even after S1 is off. To discharge, (do not press S1)
touch the electrodes to a metal object and note the healthy spark
discharge.
The Electronic Dazer was designed as a self-defense weapon for use
against vicious dogs or other attacking animals. The device is most effective
when the electrodes contact an area of low resistance such as skin or flesh.
Those include the snout or mouth since the resistance of those areas are much
lower than areas of hair or of fur. The electrodes could be pointed to penetrate
these areas better. The dazer generates great stopping power. One contact will
give a powerful jolt and should discourage any further attacks.
The device
can burn and heat materials with low resistance. Those include flesh, moistened
paper or wood, etc. That makes the unit potentially hazardous to humans.
Remember, the dazer is not a toy but a quality electrical appliance and
therefore must be treated accordingly. Use the utmost
discretion with this device!
Another use for this device is as a
high voltage DC power supply. It may be constructed as variable power supply if
output taps are taken from various stages of the voltage multiplier section.
Remember, always disconnect the battery and fully discharge the capacitors
before working with the circuitry.
Note that if you decide to 'Turbo-charge'
your unit, select diodes and capacitors which can handle the extra voltage. This
unit can easily be damaged (and stops working) by incorrect parts choice,
careless (sharp) soldering joints, and so on. So be careful and watch
yourself. Again, being careless is gonna hurt!!!
Copyright and Credits:
The author and owner of the
original project is Rick Duker. Gernsback Publishing is out of business. Project
was published in Hands-on Electronics 1987. Posted with permission of Rick J.
Duker, 2003. Copyright Rick Duker, 1987.
Again, this project is for educational and/or
laboratory purposes only and even so, it is your responsibility to check with
local, provincial, and federal law enforcement in regards to the legality for
having in possession or the construction of this project. I take no
responsibility, whatsoever, for the use, experimentation, or having possession
of this high voltage device.
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Roon