Monroe 30 User manual

h
Portable Electronic Display Calculator MOdel:3 0
rn MONROE
Litton
Monroe, The Calculator Company
Orange, New Jersey, U,S.A. • Toronto, Canada· Zurich, Switzerland
Sales and Service Throughout the World
1743-5 Printed in U,S,A,

INTRODUCTION
We'd like to extend our congratulations on your discriminating taste in
calculators.
In buying aModel 30, you have purchased the end result of
meticulous quality workmanship backed by Monroe's 60-plus years of
solid experience. Your Model 30 full function calculator features an
eight-digit display capacity, automatic constant multiplication and divi-
sion, sequential and percent calculations, floating (F)
and +(Add Mode)
decimal selection, zero suppression
for longer operating time, overflow,
underflow,
and abright, large, glare-free planar display. The spacious
keyboard and the angle
of the display facilitate desk-top as well as
hand-held operation. Once you work with Monroe's Model 30, you'll
know why we take justifiable pride in this dynamic new product.
rn
Litton MONROE Model 3
C1"
Portable Electronic Display Calculator;}<~'
operating instructions
Monroe, The Calculator Company
lIIIIIIIIllIiiII .... j~.'
©1974 Litton Busi ness Systems, Inc .• All Rights Reserved

Operating Controls
GENERAL SPECIFICATIONS
Dimensions: Length 6in. (15.2 cm); width 3.5 in. (8.9 cm);
height 2in. (5.1 cm)
Weight:
11 oz. (312 gm)
Primary Components: MaS/LSI
Model 30
PERCENT KEY
Calculates percent-
ON /OFF ages. Has add-on
DECIMAL SELECTOR SWITCH 'j and discount 1- MUL TIPL Y KEY
When Model 30 is turned on, it is :capabilities. :Enters number in display as a
automatically cleared and ready I I I multiplicand (first number In a
for use: Decimal positions are i r,::::=::~_. : multiplication sequence) or com-
F (full floating) and +(add-model. I ,CI~: pletes a calculation and sets up
CLEAR AND CLEAR ENTRY KEY - '-I-I:~':~: result as a multiplicand.
. . i OIII:JI~ J
Cle.ars Incorrect entr!es; apending I :±:" ...£;--"" "EQUALS KEY
multiplication or diVISion operation , .. ~~~§J-~ Cit It' I' t'
fl d·t" I - I omp e es amu Ip Ica Ion or
or
an over ow con IIon. (Z)(§) lID B.-, division operation.
NUMERIC ENTRY KEYS -.... I :
Enter numbers and decimal point I@](§)ffiJEJ .. ·, ~ DIVIDE KEY
exactly as you would write them. []](g)[ID[+J: E.n~ers nU~ber in displ~y as ~ .
PLUS KEY -Jro-I-r;-,"'U :d.,v,dend (first number In ad,VI-
.L:..J :slon sequence) or completes a
,Adds entry to the add register and I calculation and sets uresult as
displays the sum., Repetitive depreSSions ja dividend. p
cause repeat
addition. If depressed after MINUS KEY-
'a multiplication percentage operation, Subtracts entry from add register, displays the dif-
it adds the result to the multiplicand. ference. Repetitive depressions cause repeat subtrac-
tion. If depressed after a multiplication percentage
operation, it subtracts result from multiplicand.
3

4
OPERATING CHARACTERISTICS AND TECHNIQUES
DECIMAL SYSTEM
Enter numbers and decimal point exactly as you would write them. Entries may contain
8 whole or 7decimal digits or any combination thereof.
F(FULL FLOATING) The decimal point in results will automatically position itself
to allow maximum decimal accuracy within the 8digit display capacity, without the loss
of whole
number digits.
Example: 10-;.
3; 3.3333333
+(ADD-MODE) The last two digits in any entry will automatically be displayed as
decimals unless
the decimal key is depressed. If the result obtained by .depressing the G
orOO keys contains more than two decimal places the result will automat.ically.be
rounded to two decimal places. This special setting IS designed for convenience In
working with monetary values.
Example:
$13.75 + 145.00; $158.75
Decimal at +
Depress ~
Numbers are set as 1375 +,14500+ and displayed as 13.75, 145.00. If two zeros are not
entered, as in 145.00, the displayed number would be 1.45. An alternate method when
entering awhole dollar
amount, such as $145.00, is to depress the decimal point key
inste.ad
of entering two zeros.
DECIMAL FLEXIBILITY
The decimal setting may be changed between calculations without affecting the accuracy
of a
number being entered, or a number already stored in the calculator.
CLEAR 4ND CLEAR ENTRY KEY ~
Depression of this key clears the entire calculator unless there is an entry in progress or
an overflow condition exists. If there is an entry in. progress depression of the~ key
clears only
the display ell'try. If an overflow condition exists depression of the ~ key
clears only
the overflow condition without disturbing the constant value or results.
INSIGNIFICANT ZERO SUPPRESSION
Unnecessary zeros to the left of the most significant displayed digit are not displayed.
5

FU LLV AUTOMATIC CONSTANTS
The value entered with the 0key or the result obtained with thew ~ey is aut~mati
cally retained as a constant factor. The last divisor entered is automatically retained as a
constant divisor.
UNDERFLOW
In results containing a combination of whole and decimal digits in excess of the display
capacity of 8, the decimal point will shift to accommodate the 8 most significant digits,
not to exceed 8 whole numbers.
Example: 12345.679 x27.01 = 333456.78979
Examples: 2 x 4 = 8
2x6=12
2+4= .5
12+4=3
OVERFLOW
C at the left of the display indicates that the 8-digit display capacity has been exceeded.
The calculator must be cleared by depressing the ~ key before continuing.
Instructions:
Decimal at F
Depress ~
Enter
12345.679
27.01
Depress Display
112345.679 I
I 333456.78 I
Instructions:
Decimal at F
Depress ~
Enter
2
4
6
2
4
12
Depress Display
2. I
8. I
12. I
2. I
0.5 I
3. I
7

AUTOMATIC 5/4 ROUNDOFF IN +(ADD MODE) SETTING
In all multiplication and division operations the last digit displayed is increased by one if
the following digit would have been five or greater.
Example: 12.75 x 2.3575 = 30.058125
Instructions:
Decimal at +
Depress ~
SEQUENTIAL CALCULATION
Multiplication and division calculations are performed on the Model 30 as you would
write them. For greater accuracy intermediate results are always carried to maximum
capacity.
Example: 10 -;- 6 x 7 = 11.67
Enter
12.75
2.3575
Depress
Display
12.75 I
30.06 I
I nstructio ns:
Decimal at F
Depress
~
Enter
10
6
7
Depress
Display
I 10. I
I1.6666666 I
I
11.666666 I
9
L:
---------------~------------'--

Monroe Model 30
APPLICATIONS
ADDITION/SUBTRACTION WITH
REPETITIVE ENTRIES
EXAMPLE:
1.23
1.23
4.56
-1.39
-1.39
-5.89
-1.65 (credit balance)
INSTR UCTIONS:
Decimal at +
Depress ~
Enter Depress Display
123
ill
I 1.23 I
mI
2.46 I
456
ill
1
7.02 I
139
GI
5.631
G1
4.24 I
589
G
1-
1.65 I
Negative amounts are always indicated
by a (-l minus sign in the left of the display.
10
.~ ~
MULTIPLICATION AND DIVISION
EXAMPLE:
45.67 x 4.56 = 208.2552
INSTRUCTIONS:
Decimal at F
Depress
~
Enter
45.67
4.56
Depress
o
~
Display
I 45.671
I 208.25521
EXAMPLE:
37.55 +50.05 = 0.7502497
INSTRUCTIONS:
Decimal at F
Depress
~
11
Enter
37.55
50.05
Depress
IT]
oDisplay
[--- 37.551
I 0.75024971

CONSTANT MULTIPLICATION
AND DIVISION
EXAMPLE:
1.65x211 =348.15
1 .65 x 59 = 97.35
1.65 x 67 = 110.55
INSTRUCTIONS:
Decimal at F
Depress
~
Enter
1.65
211
59
67
EXAMPLE:
Depress
m
o
o
o
48"" 3
12 ""3
10..,.3
Display
C==T.65 I
I 348.151
I 97.351
1110.551
INSTRUCTIONS:
Decimal at F
Depress
~
Enter
48
3
12
10
Depress
[±]
o
o
o
Display
C48.1
1 16.1
I4.1
1 3.3333333 I
~
12
SEQUENTIAL CALCULATIONS
EXAMPLE:
7 ..,. 2 ..,. 1.6 x 5 x 2 = 21.875
INSTRUCTIONS:
Decimal at F
Depress
~
Enter
7
2
1.6
5
2
Depress Display
G.J I7.1
G.J I 3.5 I
WI 2.1875 I
WI 10.9375 I
oI 21.875 I
RAISING A NUMBER TO APOWER
EXAMPLE: 32=9
33= 27
34= 81
INSTRUCTIONS:
Decimal at F
Depress
~
Enter
3
Depress
o
o
o
o
Display
C==
U
3.1
I 9.1
I27.1
1 81.1
13

PERCENT CALCULATIONS
EXAMPLE: What is 16% o.f 150?
INSTRUCTIONS:
Decimal at F
Depress
~
Enter Depress
150 0
16 00
Display
c= 150.1
I24.1
Display
EXAMPLE: What % of 150 is 60?
INSTRUCTIONS:
Decimal at F
Depress ~
Enter Depress
C==' 60.1
I40.1
ill
00
60
150
EXAMPLE:
What is the amount of discount and the cost
of an article marked $30.45 less 12.5%?
INSTRUCTIONS:
Decimal at +
Depress ~
Enter
3045
12.5
Depress
[2$]
00
EI
Display'
C30.451
I 3.81 1 (discount)
I26.641 (cost)
14
EXAMPLE:
What is the tax and the total cost of an
article costing $25.20? Tax is 4.0%
~
INSTRUCTIONS:
Decimal at +
Depress ~
Enter
2520
4.0
Depress
~
00
ill
Display
I 25.20 I
I 1.01!(tax)
I26.21 !(total cost)
PERCENTAGE DISTRIBUTION
--
EXAMPLE:
Percent of
Sales
Total Sales
Detroit $
123,455
9.02
Boston
456.593
33.34
New York 789.325
57.64
$1,369.373
100%
INSTRUCTIONS:
Decimal at F
Depress
~
Enter
Depress
Display
123455 IT)
I123455.1
456593
III
1580048.1
789325
ill
I1369373.1
El
I 1369373.\
0I
1.00 I
123455 00 I
9.01543 I
456593
00
: 3334321 :
789325
00 57.64134
15

CALCULATING SIMPLE INTEREST
ON SAVING ACCOUNT
EXAMPLE:
Calculate the simple interest on an
accou nt of $1 500 at an interest rate of
7.5% for 160 days using a 360 day
year.
INSTRUCTIONS:
Decimal at F
Depress
~
..
Enter
160
360
1500
7.5
EXAMPLE:
Depress Display
ill I160.1
oI 0.4444444 I
oI 666.66661
rn:J I 49.9999951
'<
FIGURING A BILL
5 doz. @ $5.00 a doz.
discount rate =5%
tax =4%
freight charge = $5.00
16
Find: Gross
Discount Amount
Net
Tax Amount
Gross Billing
Grand Total
INSTRUCTIONS:
Decimal at F
Depress
~
Enter Depress
Display
5IE I
5.1
5GI25 HGross)
IE I
251
5llil I
1.25 i(Discount Amt.)
EJ
I
23751(Net)
GJ
123.751
4
00
Io
951(Tax Amount)
ill
I24.701(Gross
Billing)
5mI
29. 70l{Grand Total)
17