Sharp COMPET ELSI-811 User manual

ELECTRONIC CALCULATOR WITH [ELSI]
esa mooeL EL=-811
INSTRUCTION MANUAL

CONTENTS
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FEATURES
EXTERNAL FEATURES ..
KEY IDENTIFICATION
SPECIFICATIONS
HOW TO REPLACE THE BATTERY UNIT.
CAUTION ON THE BATTERY UNIT
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INTRODUCTION
Sharp's amazing Compet EL-811 incorporating two ELSIs (Extra Large Scale Integration) another
major advancement in the world of space-age miniaturization. Y ears.of pioneering research and achieve-
ment in electronic engineering have enabled Sharp to develop an exceptionally remarkable to world’s
most personal electronic calculator with one memory register and double capacity mode, offering both
maximum portability and a wide range of mathematical versatility. The EL-811 is thoroughly reliable
and carries out calculations with amazing speed and efficiency. This booklet provides a detailed ex-
planation of the Compet EL-811’s operation.

FEATURES
fe
Ultra-compact. So small, it can be operated in the palm of your hand.
The utilization of ELSIs results in the reduction of overall dimensions and weight, increased reliability
and lower operating costs.
. Double capacity
In multiplication and division, answers up to maximum numbers of 16 digits can be obtained even
though EL-811 only has 8-digit display panel.
In division, can divide 16 digits by 8 digits. The upper 8 significant digits of the quotient are
obtained as a result and the lower digits are zeros, However, the integral number of the quotient
exceeds 8 digits, only the decimal position is memorized in the lower digits.
. Wide range of calculations
In addition to its four arithmetical calculations and double capacity calculation, successive multipli-
cation and division, repeat addition and subtraction, discount or tax calculation, memory calculation
and other mixed calculations can be quickly performed with maximum efficiency.
. Convenient constant multiplication and division
In multiplication or division, multiplicand or divisor is memorized as a constant number automatical-
ly. After performing the multiplication or division, constant calculations are performed by setting
variable number and (EB) key only.
Rapid charging
When AC power is supplied to the EL-811 through the AC adaptor, with the power switch is placed
in the OFF position, the battery can be charged approximately 3-hours. After charging, the EL-811
will
operate
on
battery
power
for
approximately
3.5-hour.
When
the
battery
is
charged
in
5-hour,
it is charged more perfectly.

6. Operates on three separate power sources
AC, built-in rechargeable battery or 12V car battery as desired.
7. Convenient lamps for memory, lower digits indicator, constant mode indicator, and
battery level indicator. (Refer to page 4 ‘External features” for further detailes)
8. “Zerosuppress system” makes reading figures easier.
9. Automatic clearing system
The machine is automatically cleared when the machine is turned on. Therefore, the calculation
can be started immediately,
10. Operation is possible even in the case of momentary power failure.
Even when the power cord is disconnected during operation with AC power source, the operation
can be continued.
11. Soft lighting green display
Our specially developed non-glare green display panel eliminates eye-strain, improves reading ease.
12.Convenient carrying case.
Always ready to go with you and assist you, whether it be in the office, schoo! or at home.

EXTERNAL FEATURES
(a)
(b)
(c)
(d)
CHARGING LAMP
When operating the EL-811 on AC adaptor, this lamp indicates
at all times. This lamp also indicates during rapid charging.
When the battery voltage is below the normal limit, this lamp
will be lit and will gradually fade as the battery voltage increases.
This state indicates batteries have been charged up to some extent.
MINUS SIGN INDICATOR (—)
Automatically indicates when the result becomes negative.
CONSTANT MODE INDICATOR (K)
Turns on when multiplication or division is performed by toudh-
ing 5, (gE. im} ) key, and multiplicand or divisor is mem
ed as a constant number automatically.
This indicator is turned off when the J. . Jo &
is touched after multiplication or division. (Refer to page 28
“4. Constant multiplication and division” for further detai
LOWER DIGITS INDICATOR /
BATTERY LEVEL INDICATOR (+)
Turns on when the lower digits of double capacity are displa’
by touching the key and turns off when the upper digits
displayed. Also, turns on when calculations can’t be performed |
by the decrease of the battery voltage. In this case, the indicator
will not turn off even when io} key is touched and miscalculation occurs.

(e) MEMORY LOADING INDICATOR (I)
Turns on, when the content of memory register is not zero.
(f) POWER SWITCH
ON — OFF position.
(a) When AC adaptor is connected with calculating unit and AC power source:
0) ON position: You can operate on AC power and the battery unit will be
charged during operation. The charging lamp indicates at all times. Even when
the power cord is disconnected during operation or in the case of momentary
—o4 power failure, the operation can be continued by battery power without mis-
calculation because a power source is exchanged the battery power automatical-
ly. In these cases, the charging lamp turns off.
@ OFF position: Performed rapid charging. (Refer to page 2 “Rapid charging’)
(b) When AC adaptor is not connected with calculating unit:
cal 0 ON position: You can operate on battery power.
Q OFF position: The calculating unit is not operated.
(c) When AC adaptor is connected with calculating unit and not connected with AC power source:
ON position: You can operate on battery power and charging lamp on AC
E adaptor does not indicate.
@ OFF position: The calculating unit is not operated.

KEY IDENTIFICATION
G Clear key
Depressed once after an entry, clears only the entry. When a mistaken number is entered
after setting a function (x or +), also clears the function. Depressed twice clears all the
contents except memory register.
[o} ~6 Numeral keys
Used for entering numbers.
| + | Decimal point key
Determines the decimal point position.
Change sign key
Changes the sign of the displayed number.
EQ Multiplication key
Orders multiplication and starts operation when chain calculations are performed.
B Division key
Orders division and starts operation when chain calculations are performed.
Plus-equal key
Orders addition. Also derives product or quotient with double capacity.

[-=| Minus-equal key
Orders subtraction. Also derives product or quotient with double capacity in the case of
negative multiplier or divisor,
Depressed after multiplication or division, clears the constant mode function.
Memory recall/Clear memory key
Depressed once summons the contents of memory on the display panel. Depressed twice
successively, clears the contents of memory.
Memory-plus key
a) Without multiplication or division function:
Orders to add the displayed figures to the contents of memory register.
b) With multiplication or division function:
Orders multiplication or division and adds its product or quotient to the contert of
memory register.
Upper / Lower digits recall key
Depressed once in the answer of double capacity, summons the lower digits of the answer
on the display panel.
Depressed twice successively, summons the upper digits again.

SPECIFICATIONS
™ CALCULATING UNIT EL-811
Power source:
Capacity:
Display digit:
Double capacity:
Addition & subtraction:
Multiplication:
Division:
Decimal point:
Sign indication:
Calculations:
Components:
Display tube:
Clock frequency:
Temperature:
Power consumption:
Dimensions:
Weight:
AC 120V, 60 Hz by using. AC adaptor (EL-81)
DC 7.2V: 6 built-in rechargeable batteries (EL-84)
DC 12V: car battery by using the car adaptor (EL-85)
8 digits
16 digits (In multiplication and division)
8 digits + 8 digits = 8 digits
8 digits x 8 digits = 16 digits
16 digits + 8 digits = 8 digits
(Listing number of dividend is within 8 digits)
Complete floating decimal point system.
Minus indication lamp in case of negative.
4 arithmetical calculations, successive multiplication and division, multi-
plication and division by constant, repeat addition and subtraction,
product + product with individual product, quotient + quotient with
individual quotient, power calculation, mixed calculations, etc.
ELSIs, etc.
Mini low power fluorescence display tube.
125 kHz + 20%
0°C — 40°C (32°F — 104°F)
DC: 1.0W, AC: 1.3W, OFF (rapid charging): 1.9W
106mm(W) x 45mm(H) x 174mm(D)
4-1/7" (W) x 1-3/4""(H) x 6-3/4''(D)
600 g (1.32 Ibs.)

= AC ADAPTOR EL-81
Power consumption: 4.5w
Dimensions: 70mm(W) x 62mm(H) x 102mm(D)
2-3/4''(W) x 2-1/2'(H) x 4'(D)
Weight: 450 g. (0.99 Ibs.)
= BATTERY UNIT EL-84E (EL-84A for Canada)
Type: 6 rechargeable nickel cadmium batteries in unit: 450 mAH, 7.2V
Usable time: 3.5 hours (20°C) (72°F) (Rating)
Charging time:
Rapid charging: Approximately 3 hours (when power switch is set at OFF position with
AC adaptor) (20°C) (72°F) (Rating).
Standard charging: Approximately 13~15 hours (performed while operating on ON position
with AC adaptor) (20°C) (72°F) (Rating).
Note: Even when it is charged for longer than specified time, there is no danger of damage because of
installed safety device in the battery unit. And the charger (EL-81) controls an electric current.
Since all the rechargeable batteries tend to discharge slightly over a period of time, it is recommended
{ that all EL-811 batteries be charged before initial operation.
Note: Discharge of the battery is indicated by the battery level indicator. If this indicator remains lit,
even after depressing the i+} key continuously, charging is necessary.
= CAR ADAPTOR EL-85 (Optional unit)
This car adaptor is used when operating the EL-811 in your car on the car battery (12V).
g | CARRYING CASE (Attached)

ereneeeers
= SPARE BATTERY (Optional unit)
It is possible to charge a spare battery (EL-84), while the EL-811 is operating on DC power, with
the use of a special connector (Option).
When the battery being used is discharged, continuous operation of EL-811 can be obtained by re-
placing the discharged battery with the charged spare battery.
When
charging
the
spare
battery,
connect
the
battery
unit
(1)
with
the
special
connector
(2)
before
connecting
it
with
AC
adaptor
(3).
Rapid
charging
(3
hours)
of
the
spare
battery
is
performed.
When
charging
of
the
spare
battery
is
completed,
pull
out
AC
adaptor
(3)
before
disconnecting
the
special
connector
from
the
spare
battery
unit,
Note: The spare battery and special connector are optional.
spare battery
10

a
HOW TO REPLACE THE BATTERY UNIT
If the battery cannot be used for longer than one hours or so
even after about 5-hour charging with the power switch set
at OFF position or about 13 to 15 hours charging with ON
position, the battery life is almost terminated, In such a case,
the battery unit must be replaced with a new one.
Furthermore when the calculator is to be used for a long
time with DC power, it will be very convenient to use this
battery unit as a spare. Since the user is requested to change
the battery unit, please exchange the battery unit in a proper
manner according to the procedures mentioned below. If the
battery unit is set in a wrong way or touches the other ele-
ctronic parts, troubles may be caused. Therefore, replacement
of the battery unit must be carried out with sufficient care.
1. First set the power switch to OFF position, and then re-
move the screw located on the back of the EL-811(Fig. 1).
At this time, protect the calculator by putting a soft cloth
under the calculator. Unhook the bottom cabinet by
pulling it ahead slightly. (Fig. 2).
2. Remove the battery unit: Grasp the battery case as fig. 3
and lift up A-side while giving a power in the direction of
arrow mark.

. Remove the battery connector, as shown. (Fig. 4)
. Connect the connector to the battery unit. The black
. Set the new battery unit in place. And creep the cord of
. Replace the bottom cabinet following to the reverse
cord (thin pin) must come upside (minus). It must be
connected correctly for plus and minus, (Fig, 5)
connector, as shown, (Fig. 4)
orders of 1 and 2, and clamp it with screws,
CAUTION ON THE BATTERY UNIT
qe Comparable
to
any
type
of
battery
generally
used,
if
the
EL-811
is
left
unused
for
two
(2)
to
three
(3) months the battery unit will slowly discharge. The original state of the battery unit can be restor-
ed by several charging and discharging cycles.
.
If
a
battery
unit
is
to
be
stored
for
long
periods,
the
temperature
condition
must
be
within
-10°C
to
45°C
(14°F
to
115°F)
because
self-discharging
is
apt
to
be
influenced
by
temperature
and
the
storage
place
must
be
free
from
moisture,
or
direct
sunlight.
7

13
. Due to the characteristics of the nickel cadmium battery, 20°C to 25°C (68°F to 77°F) is the best
temperature condition for charging and discharging efficiency.
CAUTION: Charging under the temperature condition of below 0°C (32°F) should be avoided.
. When the battery voltage decreases below the normal limits, the battery level indicator (+) in-
dicates. Be sure to stop the calculation as soon as the battery voltage is decreased. If the EL-811
is used with the battery source being applied after the battery level indicator indicates, miscalcula-
tions may occur and the battery unit's life expectancy is shortened. Charge the battery unit while
operating on AC power with AC adaptor or rapid charging.
. Even defective or used batteries should not be thrown into a fire or dump into a dustbin,
It can be operated in the carrying case by DC power. But, be sure to take it out of the carrying case
when operating on AC power or charging the unit.
. Be sure to charge the battery by using AC adaptor (EL-81). Do not use other chargers.
.
Since
the
charger
EL-81
is
to
be
used
for
EL-811,
it
should
not
be
used
for
the
batteries
of
other
machines or adaptors.
For
best
results
operate
the
EL-811
on
the
battery
unit
occasionally
not
always
on
AC
power.
This
assures
battery
life
longer.

DOUBLE CAPACITY CALCULATION
Double
capacity
calculations
are
possible
in
multiplication
and
division.
Addition
and
subtraction
can
not
be
performed
in
double
capacity,
Refer
to
the
following
examples.
Ex.
In
multiplication,
summon
the
lower
digits
of
the
product
by
depressing
i+}
key
and
summon
the
upper
digits
again
by
depressing
key.
11111111
x
11111111
=
12345678
7654321.0
upper digits lower digits
Steps
|
Operation
|
Display
Note
1
|
i
i
FB
11111111,
2
|
ia
ts
Tabi
i
bp
3
|
|
12345678
K
upper
digits
4
7654321.0
Ke
}
lower
digits
5
12345678
K

Ex. When multiplication is performed (in this case the result of double capacity is the multiplicand),
the lower 8 digits in the multiplicand are regarded as zero.
88880000 x 22222 x9
Steps Operation Display | Note
1 88880000 88880000.
7} | x | 88880000. |
3 22222 22222. |
4 19750913 | “197509 1300000,000 x 9”
5 9. is carried out.
6 17775821 K upper digits
a 700000,00 K + } lower digits
Note: In above example, even if summons the lower digits by depressing i+} key at 5th step and
multiplies the lower digits by 9, the result becomes as same as above result.

Ex.
In
division,
a
maximum
capacity
of
dividend
is
16
digits
but
a
read-in
number
is
only
8
digits,
only
the
upper
8
digits
are
obtained
as
a
result.
Accordingly,
the
lower
8
digits
are
cleared,
When
the
integral
number
of
the
quotient
is
larger
than
8
digits,
only
the
decimal
point
is
me-
morized
in
the
lower
digits.
VATA Xx 1 111111 20
Steps Operation Display ¥ Note
1 14111111 11191111.
2 x | 11111111,
3 14911111 11111111,
4 + | 12345678
5 20 | 20.
6 61728393 K upper digits
2
io]
00000.000
K
+
}
lower
digits
Ex.
Addition
and
subtraction
can
not
be
performed
in
double
capacity.
98765432 + 4567890
Steps
Operation
Display
Note
1
98765432
98765432.
2
98765432.
3
4567890
4567890.
4
0.0.0.0.0.0.0.0.
|
—
Error
16

OVERFLOW ERROR DETECTION
The overflow error checking system operates for the following miscalculations.
(1) When 9 digits number is listed as integral number.
(2) When the integral number of the result exceeds 8 digits in addition and subtraction.
(3) When the integral number of the result exceeds 8 digits in memory addition and subtraction.
(4) When the integral number of the result exceeds 16 digits in multiplication and division.
(5) When the integral number that is added to or subtracted from memory exceeds 8 digits.
(6) When division is performed and divisor is zero.
In above cases, the contents stored in the memory are retained except (3). In case of (3), the content
of memory register become zero. When the overflow error is detected, all keys except G key are elec-
tronically locked, the indication will become zero and all decimal points turn on. Accordingly, to reset
the overflow error checking system, depress the G key.
el.