Specifications for Tektronix Model 31

Manufacturer: Tektronix, Inc.
Model Number: 31
Serial Number: Four Units in Museum
#1: B052789
#2: B031961
#3: BB09
#4: No Serial Number - Prototype
Introduction: August 2, 1973
Date of Manufacture: Exhibited Calculator, Late 1973
Manufactured In: USA, Beaverton, Oregon
Original Price: $2,850 Base Price at Introduction
$700 Option 01 Printer
Weight: 32 Pounds
Size: 8 3/4" Wide, 15 1/4" Deep, 6" High
Power Requirement: 100 Watts Max, Jumper Selectable 120/240V AC
Display Technology: Sperry DC Plasma SP-332 & SP-333 modules
Leading Zero Suppression (except at clear)
Logic Technology: AMI-made (to Tektronix Custom Design) LSI Chipset
Chipset essentially functional equivalent of the Cintra 909 calculator
Part Numbers: (AMI Cxxxx/Tek 156-xxxx-00)
C8684/0235, C8685/0231, C8686/0232, C8687/0233,
C8688/0234, C1836/0239, C1837/0240, C1838/0242,
C1839/0237, 2xC1840/0238, 2xC1841/0236, C1842/0243,
7400-Series TTL ICs for programmer and miscellaneous logic
Intel 2102/Signetics 2602 1Kx1 static RAM for program/memory storage
Two Main Circuit Boards (calculator and programmer)
Memory board(s) piggyback on programmer board
Digits of Capacity: 10 mantissa, 2 exponent, both with sign
12 digits calculated, 2 guard digits not displayed
Decimal Modes: Floating and Normalized Scientific Notation
Arithmetic Logic: Full Algebraic Logic w/heirarchy and parenthesis
Math Functions: Comprehensive, see exhibit for details
Constant: No
Memories: Depends on memory configuration:
Standard: 512 Program Steps, 64 Memory Registers
Option 02: 1024 Program Steps, 128 Memory Registers
Option 03: 1536 Program Steps, 192 Memory Registers
Option 04: 2048 Program Steps, 256 Memory Registers
Option 05: 2048 Program Steps, 640 Memory Registers
Option 06: 3584 Program Steps, 448 Memory Registers
Option 07: 5120 Program Steps, 256 Memory Registers
Option 08: 2048 Program Steps, 1000 Memory Registers
Option 09: 5120 Program Steps, 640 Memory Registers
Option 10: 8192 Program Steps, 256 Memory Registers
Serial #B031961 Equipped with Option 02
Serial #B057289 Equipped with Option 09
Programmable: Yes, Extensive Features
Learn-mode program step storage of up to 8192 steps (see Memories)
Complete branching, with labeled jumps
One-level subroutine capability
Program-controlled load/store to/from Mag-Tape (Chaining)
Peripherals: Optional Built-in 16-column thermal printer (Option 01)
Built-in magnetic cartridge tape drive
External devices via I/O interface (early GPIB/IEEE 488-like)
Single ROM pack slot for ROM-based applications
Model 152 General Purpose BCD Interface
Model 153 Tektronix Instrument Interface
Model 154 RS-232C Interface
Model 31/10 Graphics System
Model 31/53 Instrumentation System
Interface to Tektronix 4661 Digital Pen Plotter
Performance: Add/Subtract: 8ms
Multiply: 15-25ms
Square: 10-25ms
Divide, 1/x 15-20ms
Square Root 30-50ms
ex: 8-10ms
Loge(x): 8-10ms
Sin: 120-140ms
Cos: 140-160ms
Tan: 70-100ms

Previous Machine: Texas Instruments SR-20
Next Machine: Sharp PC-1001

Related Machines: Cintra/Tektronix 909

Advertising: Tektronix' TEKSCOPE Magazine Introduction of Model 21 and 31 Calculators [PDF, 16 Pages, 7.3MB]
Tek 21/31 New Product Flyer [97K]
Original Tek 31 8x10 Glossy Photo [36K]
"The first interactive graphic calculator." [86K]
Cover of Tek 31 Operator's Manual [41K]
Cover of Tek 31/53 Instrumentation System Brochure [67K]
"The first modular instrumentation calculator." [90K]
"Tektronix Programmable Calculators Catalog, 1973" [51K]

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