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Inside the Mark Super VII
The Hubbard Professional Mark Super VII is the most sophisticated and
expensive e-meter yet developed by the Church of Scientology. Its retail
price in 1995 was US $3,850. It is the standard e-meter in use today.
Although the earlier Mark V model is still offered for sale, for auditing
on the OT levels the Mark Super VII is required .
Hubbard Professional Mark Super VII placard
Although the Church of Scientology claims that their e-meters are made of
special high-precision components, the electronic technology in the Mark
Super VII is ordinary 1980s-era VLSI, including an Intel 8051 8-bit
microprocessor. An electrical engineer who examined the meter in November,
1995 estimated that devices of this type, custom-manufactured and sold in
low volume, would normally retail for around $300 today. That is one
twelfth the Church's asking price.
Controls and Indicators
- The Cans: electrodes used to measure skin resistance.
Normally one is held in each hand. (For solo auditing, both are held in
one hand.) Because the quality of the electrical contact depends on one's
grip on the electrodes, there is ample opportunity for tiny, unconscious
muscle movements in the fingers to influence the readings.
- Tone Arm Knob: the primary range control. At a TA setting of
2, the needle will be at the setpoint when the resistance across the cans
is 5,000 ohms. At a TA setting of 3, the needle will be at setpoint at
12,500 ohms. The meter comes with a pair of reference resistors so that
its calibration can be checked at these two values. At the start of an
auditing session the TA should be between 2 and 3.
- Trim Knob: the secondary range control. Used to fine-tune
the range setting by adjusting the needle slightly to get it to the
setpoint. (The digital display of TA value does not change when the trim
knob is moved.)
- Sensitivity Knob: fine tunes the gain on the amplifier to
control the amount of resistance change necessary to obtain a full scale
needle deflection. With too low a sensitivity setting, the needle will
just sit at the setpoint. With too high a setting, every little twitch
sends the needle offscale. A normal sensitivity value is around 5.
- Sensitivity Booster Switch: coarse control of amplifier gain.
Values are Low , Normal , and High .
- Mode Switch: values are Off, On, and Test. In Test mode the
needle should swing rightward and indicate in the ``Test'' region of the
scale. If it fails to reach this region, the batteries are low. The
needle should bang smartly off and then settle against the righthand pin
when the E-Meter is charged.
- Needle: analog needle displaying current flow across the
cans: the inverse of resistance. A leftward movement of the needle is
called a ``rise'' (increased resistance); a rightward movement a ``fall''.
- Clock: a digital clock/calendar. This is a separate circuit
board, mounted underneath the main board.
- TA Counter: Cumulative measure of ``downward'' TA motion
(counter-clockwise movement of the knob), displayed digitally. For
example, suppose the auditor moves the TA setting from 2.5 to 2.2. The TA
Counter will increase by 0.3. Only decreases in TA are counted; increases
in the TA setting are ignored by the counter. The total downward TA motion
during an auditing session is recorded on the auditor's worksheet; it is
supposed to signify ``release of charge.''
- TA Setting: digital display of current tone arm setting.
- Meter Check Button: A pushbutton that temporarily disconnects
the electrodes from the meter. A tiny amber LED located just above the
button lights up when the electrodes are disconnected. This arrangement
allows the auditor to quickly check the meter's calibration, or to check
for a malfunction if the PC is rockslamming. (The rockslam indication
could be caused by a meter fault, or by the PC touching the cans together.
If the meter checks out okay then the PC really is rockslamming and the
auditor must deal with it.) Pushing the button again reconnects the
electrodes and extinguishes the LED.
Click for full-scale image
This data plate is affixed to the bottom of the meter. The serial number
and dates have been masked in the image to prevent the Church's security
division (the Office of Special Affairs) from tracing the unit. The text
on the left side of the data plate is a disclaimer that was required by the
US FDA (Food & Drug Administration) after Hubbard's medical claims grew too
On January 4, 1963, however, the Food and Drug Administration raided the
Washington Church... The FDA seized a huge quantity of E-meters and books.
As with "Dianazene," the FDA charged mislabelling... Eventually, the FDA
won their case against the labelling of the E-Meter, and forced the
Scientologists to label it ineffective in the diagnosis or treatment of
disease. The Scientologists failed to thoroughly comply with the ordered
Here is part of the order issued by Judge Gesell in United States
v. An Article or Device "Hubbard Electrometer." et al., 333
F. Supp. 357 (D.D.C. 1971), which forbids the Church of Scientology
and all related organizations from claiming to heal using an E-Meter:
Jon Atack, A Piece of Blue Sky, p. 154
The device should bear a prominent, clearly visible notice warning that
any person using it for auditing or counseling of any kind is forbidden
by law to represent that there is any medical or scientific basis for
believing or asserting that the device is useful in the diagnosis,
treatment or prevention of any disease. It should be noted in the
warning that the device has been condemned by a United States District
Court for misrepresentation and misbranding under the Food and Drug
laws, that use is permitted only as part of religious activity, and
that the E-meter is not medically or scientifically capable of
improving the health or bodily functions of anyone.
Here is the actual wording on the Super Mark VII's data plate. As you
can see, it does not fully comply with the judge's order:
HUBBARD ELECTROMETER MANUFACTURING
By itself, this meter does nothing. It is solely for the guide of
Ministers of the Church in Confessionals and pastoral counselling. The
Electrometer is not medically or scientifically capable of improving the
health or bodily function of anyone and is for religious use by students
and Ministers of the Church of Scientology only. HUBBARD, E-METER and
SCIENTOLOGY are trademarks and service marks owned by RTC and used with its
Click for full-scale image
This is the main assembly of the Mark Super VII. The black donut-shaped
objects surrounding some wires on the main board are inductors that
suppress electronic interference between the analog and digital sides of
the device. The blue rectangular boxes arranged in a row are ``trim
pots,'' or variable resistors (potentiometers).
An internal serial number plate has been masked in the image to prevent the
Office of Special Affairs from tracing the unit.
Main circuit board
Close-up shot of the Intel 8051 microprocessor
Here is a closer view of the main circuit board. It contains an Intel 8051
microprocessor, an LCD display driver chip for the TA Setting and TA
Counter displays, and various other components.
Why Is There a Microprocessor?
The Mark Super VII would seem to be over-engineered. However, it is
capable of more than just measuring resistance across the cans. It can be
connected via a jack on the back to a ``master'' meter, so that a course
supervisor can monitor the actions of the auditor from another room. The
unit must therefore be capable of transmitting the current TA setting, TA
counter, and needle position to the master unit several times per second.
Digital technology is an appropriate solution in this case.
The Super Mark VII also accepts a ``remote tone arm:'' a little box
with its own tone arm knob that is placed to the right of the e-meter.
The box has a cable that plugs into another one of the jacks in the
back of the meter. Remote tone arms are for solo auditors, who will
want to both work the knob and take notes with their right hand while
holding the cans in their left hand. This is awkward to do using the
meter's built-in tone arm knob, since it is on the far left side of
Back side of the e-meter
This view of the outside back of the e-meter shows the four jacks. Two are
for the charger (allowing for two different plug styles), one is for the
remote tone arm, and one for connection to a course supervisor's ``master''
meter. When the charger is plugged in, a red LED lights up to indicate
that the charging circuit is active.
Also visible in the picture are two rectangular rubber feet, and two of the
three rubber grommets located on the back of the meter. Pulling these
grommets out uncovers the screws that must be removed to open the meter.
Below is a picture of the inside of the back half of the unit, showing the
connections from the jacks to the main and charger circuit boards.
Inside view of back of e-meter
Batteries and Charging Circuit
Battery board holds seven batteries (three on top side.)
See this important note about battery leakage.
The e-meter uses rechargeable Panasonic NiCad batteries. It comes with a
plug-in charger that converts house current to 12 volts/300 milliamps AC.
The charger plugs into a jack in the back of the unit, which connects to
the charging circuit board:
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