~ Early Web Links ~

A comprehensive reference hub dedicated to the Smith Chart, the classic RF engineering tool invented by Phillip Smith of RCA, covering tutorials, software downloads, example charts, reference books, and curated links to related tools and pages. Visitors can explore the mathematical foundations of impedance matching, s-parameters, and microwave design through a well-organized collection of articles, Java applets, and PDF resources.

Peter's DIY electronics hub showcases a range of original hardware projects including relay modules for Raspberry Pi and Arduino, PIC microcontroller circuits, remote control encoders, and an LCD thermometer. Each project comes with schematics and build guides, making this a great resource for hobbyist engineers looking for practical, hands-on circuit designs.

Tomi Engdahl's ePanorama.net is a vast electronics reference site covering audio circuits, video systems, PCB design, embedded systems, RF, and much more, with hundreds of categorized links and original schematics. The accompanying blog keeps the resource current with news, product tests, IoT coverage, and cleantech topics, making it a go-to hub for electronics hobbyists and engineers alike.

A comprehensive online reference covering the U.S. Navy's NEETS Module 10, this resource walks through wave propagation, transmission lines, and antenna theory with detailed chapters on electromagnetic fields, radio wave propagation, and sound waves. Published by Integrated Publishing, it offers the full technical training manual with options to download as PDF or order in print, making it a valuable reference for electronics students and hobbyists alike.

WhiskeyTangoHotel.Com is a hobbyist electronics and amateur radio blog featuring hands-on projects like ESP32 microcontroller builds, temperature logging with Node-RED, and Morse code analysis tools. The site blends practical hardware tutorials with radio operator interests, making it a great find for tinkerers who enjoy cheap microcontrollers and DIY data visualization.

Bob Robertson's hobby site is a sprawling reference on solar power, covering everything from basic definitions and how solar panels work to educational guides for kids and van-life solar setups. With dozens of articles on renewable energy topics, it reads like a one-man encyclopedia built by a retiree passionate about the subject.

Electronics Notes, created and maintained by engineer Ian Poole, is a comprehensive reference hub covering electronics theory, circuit design, components, radio technology, antennas, ham radio, and more. With tutorials aimed at everyone from hobbyists to professionals, it also offers downloadable guides, infographics, and component data sheets, making it a genuinely useful destination for anyone working with electronics.

Vacuumtubes.com, run by Jonathan Oas out of Hartland, MN, is an online storefront selling vacuum tubes, electron tubes, tube testers, tube sockets, and related electronic parts organized into extensive alphabetical tube lists. The inventory spans everything from rare Western Electric and antique tubes to popular audio types like the 12AX7, 6L6, and EL34, making it a go-to source for vintage audio and electronics enthusiasts.

Circuit Sage offers free design routines and tools for analog and RF circuit engineers, covering topics like PLL design, LNA/PA design, impedance matching, bandgap references, and transmission lines. The site provides Mathcad-based calculation routines that serve as practical references for IC and wireless circuit design work.

AimSpice appears to be a SPICE circuit simulation software site, offering tools for electronic circuit analysis and modeling. The minimalist page redirects visitors to the main document, suggesting a focused software or technical resource for electronics engineers and hobbyists.