Arithmetic Tutor

The Limrose Digital Arithmetic Tutor released in 1975 is an advanced logic trainer designed for teaching binary arithmetic and 4-bit data word manipulation to senior students who have completed basic courses in combinational and sequential logic circuits. 

Description of its components and capabilities:

Components

• Three 4-bit Shift Registers
• Two 4-bit Synchronous Binary Counters
• One 4-bit Comparator
• One 4-bit Adder
• One Carry Store
• One J-K Master-slave Flip-flop
• Four 2-input NAND Gates
• Four 2-input AND Gates
• Three Logic Inverters

Input and Display

• Two manual Single Pulse Generators
• One Continuous Clock Pulse Generator
• Red light-emitting diodes (LEDs) for displaying logic states on the anodized aluminium front panel

Connectivity

• Limrose's 1mm gold-plated terminal pin and patch lead system for interconnections

Educational Content

The accompanying illustrated instruction book covers various computer circuits that can be constructed using the equipment, including:

1. Loading and shifting of registers
2. 1's and 2's complements
3. Addition and subtraction of 4-bit numbers (serial and parallel methods)
4. Multiplication and division using the shift-and-add method

Additional topics covered in the instruction book:

• Octal Number System
• Binary fractional notation
• Overflow conditions in fixed-point arithmetic

The Digital Arithmetic Tutor is designed as a practical teaching aid, allowing students to experiment with and visualise complex digital logic concepts. It builds upon simpler combinational logic tutors by incorporating more advanced components like shift registers and binary counters, enabling the exploration of arithmetic operations and data manipulation techniques essential in computer architecture.

Here you find 3 models, 3 with images and 0 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from Limrose Electronics Ltd., Limrose Group Ltd.; Cheshire