In the warm glow of the MicroBasement, BUGbook II — formally titled *Logic & Memory Experiments Using TTL Integrated Circuits* — is a foundational lab manual for digital electronics beginners. Published in 1974 by E & L Instruments as part of the early BUGbook series, this paperback provided over 50 experiments on TTL logic gates, flip-flops, counters, shift registers, and memory circuits. Co-authored by two Virginia Tech educators, it used simple, affordable hardware (the E & L MMD-1 breadboard or equivalent) to teach digital design through hands-on building and testing. In the MicroBasement collection, BUGbook II sits proudly beside the 8080A BUGbook, TTL Cookbook, and early digital logic hardware — the second step in a series that introduced thousands to TTL and paved the way for microprocessor experiments.
Published in 1974 by E & L Instruments (with later editions through Howard W. Sams & Co.), BUGbook II was written by:
The duo of Virginia Polytechnic Institute and State University (Virginia Tech) educators created the BUGbook series to make digital electronics accessible. BUGbook II focused on logic and memory, building on BUGbook I's introductory gates and combinational logic, and setting the stage for later microprocessor volumes.
The book is organized around over 50 experiments, each with objectives, theory, circuit diagrams, parts lists, step-by-step procedures, data tables, and review questions. It starts with basic TTL logic families (7400 series characteristics, fan-in/fan-out, power supply, noise immunity) and progresses to flip-flops (RS, JK, D types), counters (binary, decade, up/down), shift registers (serial-in/serial-out, parallel load), and memory circuits (static RAM, ROM applications, address decoding). Experiments include building astable multivibrators, ripple counters, synchronous counters, ring counters, Johnson counters, shift-register generators, and simple RAM arrays. Appendices provide TTL pinouts, truth tables, and breadboarding tips.
BUGbook II was designed for the lab or workbench: experiments used inexpensive TTL ICs (74 series), required basic tools (breadboard, power supply, switches, LEDs, logic probes), and included clear wiring diagrams for immediate building. The authors emphasized understanding waveforms with scopes or probes, troubleshooting common issues like bounce or race conditions, and extending experiments (e.g., adding presettable counters or memory expansion). It was ideal for self-learners or classroom use, with many hobbyists using it to build their first digital projects before moving to microcomputers.
BUGbook II represents one of the critical turning points in digital electronics education. By providing simple, verifiable experiments on TTL logic and memory, Rony and Larsen gave students and hobbyists the practical skills needed to design and build real circuits — the building blocks for the microprocessor revolution that followed. It influenced countless introductory courses, self-taught builders, and early digital projects, helping bridge the gap from basic gates to complex systems. Preserving and demonstrating this book is essential because it embodies the foundational efforts of educators and engineers who created the pathways for modern digital design. In the MicroBasement, its well-thumbed pages rest beside the 8080A BUGbook, TTL Cookbook, and early TTL chips — a quiet reminder that the best way to learn digital logic is to plug in the ICs, wire the breadboard, and watch the signals come alive.