Telephone Projects for the Evil Genius – A Complete Guide
Table of Contents
- Introduction
- Who is the Evil Genius Series For?
- About the Author: Tom Petruzzellis
- The Legacy of Telephone Technology
- Overview of the Book
- Structure and Format
- Core Tools and Components
- Chapter-by-Chapter Summary
- Top 10 Projects Explained
- Technical Skills You’ll Learn
- Safety Guidelines in Telephone Projects
- Applications in Education and DIY Culture
- Vintage vs Modern Phones: Bridging the Gap
- Legal Considerations in Phone Modifications
- How to Source Components for Projects
- Integrating Arduino and Microcontrollers
- Troubleshooting Guide
- Real-Life Applications and Case Studies
- How This Book Supports STEM Learning
- Final Review and Conclusion
1. Introduction
“Telephone Projects for the Evil Genius” is one of the most intriguing titles in electronics literature. It brings together creativity, science, and mischief in one compact book. Published under McGraw-Hill’s TAB Electronics label, this book offers a goldmine of experiments, builds, and hacks for telephony systems — both vintage and modern.
In an era of smartphones and cloud-based communication, why should one care about telephone circuits? Because at their core, all communications are rooted in the same electronic principles — signals, switches, tones, and logic.
2. Who is the Evil Genius Series For?
The Evil Genius series caters to:
- Hobbyists
- Students of electronics
- Makers and tinkerers
- DIY tech enthusiasts
- Educators seeking hands-on projects
This book in particular appeals to those fascinated by telecommunication, vintage technology, and electronics engineering. It’s both a teaching tool and a playground.
3. About the Author: Tom Petruzzellis
Tom Petruzzellis is a seasoned electronics engineer, educator, and writer. With more than a dozen electronics books to his name, Tom's writing emphasizes:
- Accessibility: Projects for beginners to experts
- Practicality: Real-world applications
- Affordability: Uses common components
- Innovation: Encourages curiosity and hacking
His experience as an electronics lab supervisor ensures the accuracy and educational value of every build.
4. The Legacy of Telephone Technology
Before the internet and cellular networks, landline telephony was the core of global communication. Understanding these systems unlocks deep insights into:
- Analog signals and modulation
- Tone generation and decoding
- Switching systems
- Signal transmission
- Power over line systems
Petruzzellis reintroduces these concepts using modern project ideas that give new life to old tech.
5. Overview of the Book
“Telephone Projects for the Evil Genius” offers:
- 40+ hands-on projects
- Clear schematics
- Illustrated diagrams
- Step-by-step instructions
- Component sourcing tips
- Tips for modifying landlines and mobile phones
- Concepts behind every build
It’s written in a format that balances fun with learning.
6. Structure and Format
The book is divided into:
- Introductory chapters on phone systems
- Component guides (resistors, capacitors, ICs)
- Project tutorials (simple to advanced)
- Testing and troubleshooting steps
- Appendices with reference materials
Every project follows this layout:
- Objective
- Materials
- Circuit diagram
- Build instructions
- Testing and expected results
7. Core Tools and Components
Projects in this book use affordable, easily available components like:
- 555 Timer IC
- Relays
- Transformers
- Resistors and capacitors
- Ring detectors
- Tone decoders (like MT8870)
- Arduino (for extensions)
Basic tools include:
- Soldering iron
- Multimeter
- Breadboard
- Screwdriver set
- Wire cutters and strippers
8. Chapter-by-Chapter Summary
Here’s a brief overview of some key chapters:
Chapter 1: Understanding Telephone Systems
Covers analog signal transmission, tone dialing (DTMF), pulse dialing, line voltage.
Chapter 2: Project Basics
How to read schematics, safety tips, how telephone wiring works.
Chapters 3–12: Project Builds
Each chapter introduces 3–5 projects. Example topics include:
- Creating a line status monitor
- Building a ring generator
- Setting up a call-recording system
- Tone-triggered switches
- Secret spy phone line taps
Final Chapters: Advanced Projects
Include microcontroller integrations, phone security systems, and GSM hacks.
9. Top 10 Projects Explained
Let’s review 10 of the coolest projects from the book:
1. Line Seizure Circuit
Allows you to take control of a shared line (great for intercom setups).
2. DTMF Decoder
Decode touch-tone signals into digital outputs using MT8870 IC.
3. Phone Bug/Line Tap (for legal use only!)
Monitor phone activity with a basic audio tapper.
4. Ring Generator
Mimic phone company ring voltage to test devices offline.
5. Line Status Indicator
LED-based circuit that shows when the line is in use.
6. Phone-Operated Appliance Controller
Use phone tones to turn on lights or fans remotely.
7. Rotary Dial to Digital Encoder
Convert an old rotary phone’s pulses into digital signals.
8. Voice-Activated Dialer
Trigger dialing based on sound level.
9. Cell Phone Remote Starter
Call a number to activate a relay that could start a motor or device.
10. Intercom System
Create a two-way intercom from salvaged phones.
10. Technical Skills You’ll Learn
Through the book, you’ll gain:
- Circuit design fundamentals
- Schematic reading
- Soldering and breadboarding
- Telephone signal principles
- Troubleshooting skills
- Component analysis
- Signal filtering
- Microcontroller interfacing
11. Safety Guidelines in Telephone Projects
Because telephone lines carry up to 90V AC (ring voltage), safety is crucial:
- Always unplug lines before modifying
- Use opto-isolators for circuit protection
- Ground circuits properly
- Never tamper with service provider equipment
- Use fuses and protection diodes where needed
12. Applications in Education and DIY Culture
Educators use these projects to:
- Teach circuits and logic
- Demonstrate real-world electronics
- Promote hands-on STEM activities
- Inspire creativity and engineering thinking
Makers use it for:
- Smart home ideas
- Retro tech mods
- Arduino integrations
- Art installations
13. Vintage vs Modern Phones: Bridging the Gap
Many projects connect vintage rotary phones to modern logic systems. Examples include:
- Using DTMF decoders to control relays
- Turning rotary dials into keyboard encoders
- Using phone bells as door alerts
This bridge of old and new is what makes the book exciting.
14. Legal Considerations in Phone Modifications
Modifying telecom devices can be illegal if:
- You tap a phone without consent
- Interfere with a public phone system
- Transmit unauthorized signals
Always:
- Use projects on your own devices
- Avoid public or commercial telecom lines
- Follow your country’s laws
15. How to Source Components for Projects
You can find needed parts from:
- Online retailers (Amazon, Digi-Key, SparkFun)
- Local electronics stores
- Salvaged devices (old phones, fax machines)
- Thrift shops and recycling centers
Tools can be obtained from hardware or electronics shops.
16. Integrating Arduino and Microcontrollers
Advanced users can integrate:
- Arduino for tone detection
- Relays for switching
- LCDs for call logs
- Bluetooth or GSM modules for remote control
These extensions bring the Evil Genius projects into the IoT age.
17. Troubleshooting Guide
Common issues and fixes:
- No power: Check line voltage, polarity, and fuse
- No ring: Inspect generator circuit, test with external supply
- DTMF not decoded: Confirm tone purity and decoder IC
- Line busy all the time: Test for shorts or faulty seizure relay
18. Real-Life Applications and Case Studies
Some readers have used the book to:
- Build call logging systems for business
- Create private intercoms in large homes
- Hack rotary phones into smart home controllers
- Use old handsets as VOIP headsets
19. How This Book Supports STEM Learning
Educators value this book because it supports:
- Critical thinking
- Engineering design processes
- Electrical safety awareness
- Understanding telecommunications
- Encouraging experimentation
Many high school and college programs include these projects in labs.
20. Final Review and Conclusion
“Telephone Projects for the Evil Genius” by Tom Petruzzellis is more than a DIY guide — it's a learning experience wrapped in creativity and hands-on engineering. Whether you're a student, teacher, hobbyist, or hacker, this book offers timeless knowledge in a fun and engaging way.
You’ll not only learn how to build 40+ circuits — you’ll understand how phone systems work and how to innovate using them.
It’s a must-have for your electronics shelf.
