EAI 580 User manual

ANALOG/HYBRID COMPUTING SYSTEM
REFERENCE HANDBDDK

ANALOG/HYBRID COMPUTING SYSTEM
REFERENCE HANDBDDK
© ELECTRONIC ASSOC1ATES. INC. t968 • PRINTED IN U.S.A •• PUBL. NO. 00 800.2055.0 • MARCH '968

RELATED PUBLICATIONS
The table below lists other publications which ma.y be of interest to the readers of this manual.
Unless otherwise indicated by title or footnote, all are maintenance handbooks. Note that main-
tenance handbooks directly applicable to a particular system are normally supplied with the sys-
tem.
Title
Handbook of Analog Computation
Basics of Parallel Hybrid Computation
580
Reference Handbook
580
Console Components Manual
580 Computing Components Manual
580 Logic
Expansion Group
580/680 Digital Voltmeter, Model 26.268
TR20/TR48 Repetitive Operation Display Units,
Models 34. 034 and 34. 035
Publication Number
00 800. 0001-3
07 800.0016-0
00 800.2055-0
00 800.2056-0
00 800. 2057 -0
00 800.2058-0
00 800.2059-0
00 800. 2024-1

M226-S
NOTIC E
In
order to enable us to process your requests for spare parts and replacement items quickly
and efficiently, we
request your conformance with the following procedure:
1. Please specify the type number and serial number of
the basic unit as well as the EAI part number and de-
scription of the part when inquiring about replacement
items such as potentiometer assemblies or cups, re-
lays, transformers, precision resistors, etc.
2. When inquiring about items as servo multipliers, re-
solvers, networks, printed circuit assemblies, etc.,
please specify the serial numbers of the major equip-
ment with which the units are to be used, such as:
Console, Type 8811, Memory Module, Type 4.204,
Serial No. 000, etc. If at all possible, please in-
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under which the equipment was originally procured.
Your cooperation in supplying the required information will speed the proceSSing of your requests
and aid in assuring that the correct items are supplied.
It is the policy of Electronic Associates, Inc. to supply equipment patterned as closely as possi-
ble to the requirements of the individual customer. This is accomplished, without incurring the
prohibitive costs
of custom design, by substituting new components, modifying standard com-
ponents, etc., wherever necessary to expedite conformance with requirements. As a result,
this instruction manual, which has been written to cover standard equipment, may not entirely
concur in its content with the equipment supplied. It is felt, however, that a technically quali-
fied person will find the manual a fully adequate guide in understanding, operating, and main-
taining the equipment actually supplied.
Electronic ASSOCiates, Inc. reserves
the right to make changes in design,
or to make additions to or improve-
ments in its product without imposing
any obligation upon itself to install
them on products previously manufac-
tured.
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ANALYSIS AND COMPUTATION CENTERS
Princeton Analysis and Computation Center: U.S. Route No. I, P. O. Box 582, Princeton, New Jersey 08541, Telephone: 609·
452-2900
Los Angeles Analysis and Computation Center: 1500 East Imperial Highway, EI Segundo, California 90245, Telephone: 213-
322-3220, TWX 910-348-6284
San Francisco Analysis and
Computation Center: 4151 Middlefield Road, Palo Alto, California 94303, Tel: [phone],
TWX 910-373-1241
Washington, D. C. Analysis and Computation Center: 12260 Wi IKins Avenue, Rockville, Maryland 20852, Tel: 301-933·4100
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07740
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EAI :LECTRONIC ASSOCIATES, INC. Wul L.a.,,,,,,,,, N_ J=y 07764
ADVANCED SYSTEMS ANALYSIS AND COMPUTATION SERVICES/ANALOG COMPUTERS/DIGITAL COMPUTERS/HYBRID ANALOG-DIGITAL COMPUTATION EQUIPMENT/ANALOG AND DIGITAL
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TION SYSTEMS/TEST AND CHECK-OUT SYSTEMS/MILITARY AND INDUSTRIAL RESEARCH AND DEVELOPMENT SERVICES/FIELD ENGINEERING ANO EQUIPMENT MAINTENANCE SERVICES.
Bulletin No. IL-641D4-10
July, 1967

CONTENTS
CHAPTER 1 - GENERAL DESCRIPTION AND OPERATION OF THE
580 ANALOG/HYBRID COMPUTING SYSTEM
1.1 'GENERAL DESCRIPTION •..•.•••.•.•.••.•.••••••.
1.2 OPERATING CONSIDERATIONS
1-1
1-1
1.3 KEYBOARD PANEL .. •. • •. ••••• •• ••••••••• . . . . ••• 1-14
1.4 ANALOG READOUT PANEL ••.••••.•••.•••.•...•..• 1-21
1.5 THE AUXILIARY CONTROL PANEL •....•••••.•.•.•. 1-21
1.6 THE LOGIC-CONTROL AND INDICATOR PANEL ••••.•• 1-25
1.7 READOUT DEVICES
1-28
CHAPTER 2 - OPERATIONAL AMPLIFIERS
2. 1 INTRODUCTION .....•.....•....•...•.......•...
2-1
2.2 DUAL DC AMPLIFIER PATCHING
2-1
2.3 QUAD DC AMPLIFIER PATCHING
2-4
CHAPTER 3 - ATTENUATORS AND FEEDBACK LTIMITERS
3. 1 ATTE'NUATORS
3-1
3.2 FEEDBACK LIMITER 3-1
CHAPTER 4 - INTEGRATORS
4.1 INTRODUCTION 4-1
4.2 INTEGRATOR TRAYS 4-1
CHAPTER 5 - QUARTER-SQUARE MULTIPLIERS
5. 1 INTRODUCTION .•..•...•••••.•.••...•.••... 0 •••
5-1
5.2 MODEL 0.7.0146 AND 0.7.0148 QUARTER-SQUARE
MULTIPLIERS ....•.•.•.•.•.•.•.•••.•••....•
5-1
5.3 MODEL 0.7.0150 QUARTER-SQUARE MULTIPLIER ....
5-8
i

ii
CONTENTS (Cont)
CHAPTER 6 - LOG X DIODE FUNCTION GENERATORS
6. 1 INTRODUCTION .•••.•.•.••.••••.••••••.••.••.•.
6.2 OPERATING CONSIDERATIONS
6.3 OPERATING INSTRUCTIONS
.........'.............
CHAPTER 7 - THE TRACK-STORE, D/ A SWITCH TRAY
7.1 INTRODUCTION
7.2 THE TRACK-STORE CIRCUIT •••••.••••••••••••.•.
7.3 TIlE D/A SWITCH .•.•.•.•••••...••.•.•.•..•..•.
CHAPTER 8 - THE MDFG
8.1 INTRODUCTION
8.2 LOCATION AND ADDRESSING •.•....•••••••••.••••
e.3 APPLICATIONS
8.4 SETUP PROCEDURE
CHAPTER 9 - COMPARATORS AND FUNCTION RELAYS
9. 1 INTRODUCTION ....•.•..•••...•.••.•.•.•..•.•..
9•2 THE COMPARATOR
9.3 FUNCTION RELAYS
CHAPTER 10 - CONTROL TRAY
6-1
6-1
6-1
7-1
7-1
7-1
8-1
8-1
8-1
8-1
9-1
9-1
9-1
10.1 INTRODUCTION •••••••. ••••. •••. . . ••••• ••. •••• 10-1

CONTENTS (Cant)
CHAPTER 10 - CONTROL TRAY (Continued)
10.2 DVM PATCH TERMINAL ....•••••..•...••.••.•.•.. 10-1
10.3 VM PATCH TERMINAL
10.4 IC AND OP PATCH TERMINALS
10.5 SCOPE PATCH TERMINALS
10.6 PLOTTER PATCH TERMINALS
10.7 CHT ON PATCH TERMINALS
10.8 RDAC PATCH TERMINAL
10.9 A SEL PATCH TERMINAL
10.10 TIMER PATCH TERMINALS
10-1
10-1
10-3
10-3
10-3
10-3
10-3
10-3
10.11 OVD, ORR, AND OLS PATCH TERMINALS •..•.•.•... 10-4
10.12 PP PATCH TERMINAL ..•...•........•...•.••..•. 10-4
APPENDIX 1 - SIMPLE CIRCUITS USING AMPLIFIERS AND ATTENUATORS A1-1
APPENDIX 2 UNITY SCALING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A2-1
APPENDIX 3 - TRANSFER FUNCTION SIMULATION .....••... 0...... A3-1
APPENDIX 4 - REPRESENTATION OF CONSTRAINTS AND NONLINEARITIES A4-1
APPENDIX 5 - LOGIC PATCHING
APPENDIX 6 - BIBLIOGRAPHY
A5-1
A6-1
iii/iv

Figure
Number
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
1.10
1.11
1.12
1.13
1.14
1.15
1.16
2.1
2.2
2.3
3.1
ILLUSTRATIONS
Title
580 Analog/Hybrid Computing System
Typical Pre-Patch Panel Field Layout
.I
Physical Layout of the 580 Computer
Amplifiers with Four-Pin Bottle Plugs Providing
Feedback ••.••••••••••..••••••.•••••••••.••••
DVM Zero Adjustment Location
Pre-Patch Panel Insertion
Amplifier Balance Control Locations
Computer Component - Field Assignment Areas
Removal of Computing Component
Patching Block Replacement ..••••••••••.•••.•••
Keyboard ...•..••.•..•...••••..•..•....••.•....
Analog Readout Panel
Auxiliary Control Panel
Logic Control and Indicator Panel
Digital Patch ·Panel
Readout Device Connectors
580 Operational Amplifiers (Patch Block Layout
and Simplified Schematics) •••.••••.•••••.•••
Dual Amplifier, Typical Patching Configurations
Quad Amplifier Patching Configuration
Attenuators
viii
1-2
1-3
1-5
1-6
1-8
1-9
1-10
1-12
1-13
1-15
1-22
1-23
1-26
1-27
1-30
2-2
2-3
2-4
3-2
v

vi
Figure
Number
3.2
3.3
3.4
3.5
4.-1
4.2
4.3
5.1
5.2
5.3
5.4 .
5.5
5.6
5.7
5.8
6.1
6.2
7.1
7.2
ILLUSTRATIONS (Cont)
Potentiometer Configurations
3-3
Feedback Limiter Patching Block
•• 0 ••••••••••••
3-5
Typical Limiter Patching
3-5·
Limit Curve
3-6
Integrator Patching Blocks
4-2
Typical Integrator Patching
4-3
Integrator Used as a D/A Switch
4-5
Quarter-Square Multiplier Patch Blocks
5-2
Quarter-Square Mu~~ip1ier, Simplified Diagram
5-3
Multiplier Patching for Multiplication
........
5-4
Multiplier Patching
for
Division
..............
5-5
Multiplier Patching
for Squaring
(Two
Squaring
Circuits
Shown) .............................
5-6
Multiplier Patching for Square Root
5-7
Multiplier Patching for Multiplication
5-9
Multiplier Patching for Division
5-10
Log X DFG, Simplified Schematic and Patch Block
6-2
Log X DFG Patching
6-3
Track/Store, D/A Switch Patch Block
7-2
Track/Store Circuit, Simplified Diagram
7-3

Figure
Number
7.3
7.4
8.1
8.2
8.3
8.4
8.5
8.6
8.7
8.8
9.1
9.2
10.1
ILLUSTRATIONS (Cont)
Title
Tis Patching (Typical)
D/A Switch Patching (Typical)
MDFG Patching Terminations
Typical Ten-Segment Function
Effect of Changing Slope Pot 5 on DFG Output
DFG Setup Panel (Lower DFG Drawer)
Upper DFG Drawer
Typical Function Requiring Slope Amplification
Initially Horizontal Eleven-Segment Function .•
A Typical Twenty-Segment Function
Comparator and Function Relay Pa'tching Area
Typical Comparator Patching
Control Tray Patch Panel
7-4
7-5
8-2
8-5
8-7
8-8
8-10
8-15
8-21
9-2
9-3
10-2
vii

Figure 1.1 ~ 580 Analog/Hybrid Computing System
viii

CHAPTER 1
GENERAL DESCRIPTION AND OPERATION OF THE
580 ANALOG/HYBRID COMPUTING SYSTEM
1.1 GENERAL DESCRIPTION
The EAI 580 Analog/Hybrid Computing System (Figure 1.1) is composed of solid
state computing components. The 580 (categorized as a desk-top computer) is
compact in size and operates with stability and precision in a normal office
or classroom environment as well as a computer laboratory. Each component
has input and output terminations on the computer pre-patch panel for inter-
connection by bottle plugs and patch cords. The pre-patch panel is arranged
in a series of 8 similar patching fields (Figure 1.2), with each field separated
horizontally by either a control or trunk trays. The modular design tends to
eliminate patching clutter caused by long across-the-panel patching.
The main control panel is located to the lower left of the analog patch panel
(Figure 1.3). This area contains a majority of the operating controls.
The analog readout panel, located to the far left of the analog patch panel,
contains the overload indicators, DVM readout (an expansion) and a multi-
range voltmeter.
The Auxiliary Control Panel, immediately to the left of the analog patch panel,
includes 10 handset potentiometers, and override controls for both the compar-
ators and the function relays.
The area below the analog patch panel contains two manual diode function
generator (MDFG) drawers. The lower drawer contains the set-up amplifier and
controls, and up to four, 10-segment MDFGs. The upper drawer is used to house
additional segments as required.
The logic package, located at the upper left of the analog patch panel, con-
tains the logic patch panel and various indicators and controls for the logic
components.
1• .2 OPERATING CONS IDERATIONS
1.2.1
General
The 580 is completely tested and calibrated at the time of manufacture and is
shipped with all components in place. After performing the installation check-
out procedure outlined in the 580 Maintenance Manual, the computer is ready for
operation.
It should be noted that the low voltage levels used in the 580 eliminate any
shock hazard when patching with the pre-patch panel in the computer. Current-
limiting circuits protect the reference supplies from damage when they are in-
1-1

Figure 1.2. Typical Pre-Patch Panel Field Layout
1-2

ANALOG
READOUT
PANEL
LOGIC PATCH
PANEL
ANALOG PATCH
PANEL
Figure 1.3 . Physical Layout oj the 580 Computer
MDFG
DRAWERS
1-3

1-4
advertant1y patched to ground or to each other. (Dangling patch cords rarely
short to ground because of the plastic patching blocks and because the metal
strips between the patching block are covered with a scratch-resistant, non-
conductive paint.)
1.2.2
Preliminary Operating Considerations
The following steps are recommended prior to operating the 580 to prevent
possible false trouble indications.
1. Be sure that all operational amplifiers have four-pin bottle
plugs properly placed and seated as shown in Figure 1.4.
This provides the amplifier with feedback. The procedure for
inserting and removing the pre-patch panel is described in
Paragraph 1.2.3.
2. Turn. the computer on and depress the SP (set pot) button.
Initially, the overload lamps of the operational amplifiers
will light due to transients; after a few seconds, all of
the lamps should extinguish.
3. Check the various supply voltages of the 580. All power supply
outputs are connected directly to the voltmeter FUNCTION switch
(through appropriate scaling resistors); thus, the check may
be accomplished simply and rapidly. (See Paragraph 1.3.5 of
this section.)
4. Allow a few minutes warm-up (at least 1/2 hour for the DVM)
time to assure that the computing components (including the
DVM) are up to normal operating temperature. Ground the
input,termination in "pp" address mode designated DVM on the
control tray and adjust the DVM zero control (Figure 1.5) for
a +0.000 reading. Should the polarity relay begin to chatter,
turn the zero control slightly clockwise until the chatter
stops and the indicators retain the +0.000 display. The DVM
zero adjustment should be checked daily. Initially, this ad-
justment may be required more frequently due to aging of the
components.
5. Closed relay contacts provide a lOOn feedback resistor for
the operational amplifiers when in the set pot mode of the com-
puter (SP button on the control panel depressed). (This
feature permits pre-patch panel removal without overloading
the amplifiers.) However, when the computer is switched from
set pot to another mode, the relay contacts open and the ampli-
fier feedback loop is determined by the patching on the pre-
patch panel. The amplifier overload indicators may be trig-
gered momentarily during the switching time. This is of no
consequence since the computer should always be placed in the
initial condition mode before going to the operate mode.

4-PIN
BOTTLE
PLUGS
4-PIN
BOTTLE
PLUGS
THE SE PINS
JUMPERED
Figure 1. 4. Amplifiers with Four-Pin Bottle Plugs Providing Fe ed back
1- 5

1-6
DVM ZERO
ADJUSTMENT
DVM
READOUT
F igure 1.5. DVM Ze ro Adjustment Location

1.2.3
Pre-Patch Panel Insertion and Removal
To
insert the pre-patch panel, align the lugs on the bottom of the pre-patch
panel frame with the slots in the bottom rail of the patch bay (Figure 1.6).
Push the pre-patch panel forward until the lugs on the top of the frame mate
with the slots on the top rail of the patch bay. Gently slide the pre-patch
panel slightly to the right. Depress the ENG switch. (The computer auto-
matically goes into the set pot mode when the ENG switch is depressed.) The
patch panel drive system faces the pre-patch panel to the right into the locked
position.
Depressing the DIS pushbutton disengages the locking system and forces the pre-
patch panel to the left for removal.
1.2.4
Amplifier Balance
'For accurate computation, the operational amplifier must remain balanced. The
amplifier must produce a zero output voltage when the combined effects of the
input voltages or the absence of input voltages demand it. With this ,require-
ment in mind, the amplifiers contain chopper stabilization circuits to minimize
the effect of component drift. Under normal circumstances, the amplifiers do
not require balancing for several weeks. However, it is desirable to check
this condition periodically; if an amplifier is found to be unbalanced, an
adjustment is required. The amplifier balance is checked as follows:
1.2.5
1. Allow a warm-up of 15 to 30 minutes. Place the voltmeter
FUNCTION switch in the ABAL position and depress the SP
pushbutton of the MODE switch.
2. Use the signal selector system to connect the stabilizer
output of each amplifier to the voltmeter. Select AOO and
proceed in order. In each case, the voltmeter should reg-
ister a deflection that is less than 1/2. division on the
meter scale.
3. If an amplifier causes a larger deflection, the amplifier
should be balanced. The balance controls for amplifiers are
located behind the pre-patch panel on the front block of the
amplifiers (Figure 1.7). Adjust these controls for a zero
reading on the voltmeter.
Changing Computational Components
In the solution of some problems, it may be necessary to add a computing com-
ponent to the existing complement. Since some of the module positions are de-
signed to handle more than one type of computing component, a component not
required in the problem investigation may be removed and another unit inserted
in its place. Figure 1.8 illustrates the various positions of the computing
component in the 580 field area. The diagram shows which type of computing
component is compatible with each position. The procedure for replacing a
computing component and changing the pre-patch panel patching block is described
in the following paragraphs.
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