Electronics
45 sites
http://sss-mag.com/smith01.html
SSS Online is a long-running RF and spread spectrum engineering magazine offering deep technical resources on Smith charts, S-parameters, impedance matching, Eb/N0, and link budgets. Managed by Pegasus and active since 1995, it serves RF engineers and ham radio enthusiasts with articles, software downloads, tutorials, and reference material on microwave and wireless design topics.
https://cryothene.neocities.org/
Cryothene is a technically-minded personal blog covering electronics projects, embedded systems, reverse engineering, and 3D printing, with standout documentation of a custom display driver project called Sharpie spanning many installments. The site also mixes in anime opinions, game reviews, and occasional recipes, but the dominant draw is its detailed hardware and microcontroller writeups.
https://epanorama.net/
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.
https://elm-chan.org/
ChaN's personal electronics engineering site showcases hobby projects, technical notes, and software tools shared with enthusiasts worldwide, including the widely-used FatFs filesystem module for embedded systems. The site blends circuit designs, fluorescent lamp ballasts, and downloadable code under a Creative Commons license, making it a genuine resource for hardware hobbyists.
http://redcircuits.com/
RED Free Circuit Designs is a hobbyist electronics resource offering dozens of free audio amplifier schematics, preamplifier modules, headphone amplifiers, and miscellaneous electronic circuit designs. Visitors can browse Class-A and Class-B amplifier projects, phono preamps, intercom circuits, and many more practical designs, all available at no cost.
http://ka7oei.blogspot.com/2026/03/modifying-mfj-5008-parabolic-ultrasonic.html
KA7OEI is Clint's technically-focused amateur radio and electronics blog, covering hands-on modifications and experiments with devices like the MFJ-5008 parabolic ultrasonic receiver. This particular post dives deep into improving the sensitivity and frequency response of the discontinued ultrasonic tool, with detailed photos, circuit analysis, and practical applications like bat detection and power line fault finding.
https://jedaler.tripod.com/elec.html
Jedaler's Electronics Page, built by JaKab-Daniel, is a curated link collection focused on circuit schematics, microcontrollers, RF antennas, robotics, and hobby electronics projects. Visitors will find references to PIC microcontroller resources, Tesla-related circuits, xenon flash designs, and free energy machine plans alongside general electronics archives.
http://audible.transient.net/archive
The Music Electronics µArchive is a long-running reference hub for DIY guitar effects and audio electronics, offering schematics archives, FAQs, and curated links to the best resources on the web. Highlights include a downloadable schematics archive, guides on tube amplifiers and transistor identification, and an Electro-Harmonix parts sheet for builders working with vintage pedal components.
https://tonnesoftware.com/
Tonne Software offers a catalog of free and low-cost electrical engineering programs for Windows, covering filter design, meter scale drawing, great-circle mapping, Smith charts, and more. The site also hosts technical articles and tutorials on topics like speech processing, AM demodulators, and CW bandpass filters, many published or submitted to QEX magazine.
https://gadgeteer.us/
Bill Meara's Gadgeteer site is a celebration of electronic homebrewing, centered on ham radio projects including DSB and SSB rigs, tube receivers, and QRP builds alongside a popular podcast called SolderSmoke. The site also ventures into amateur astronomy, model rocketry, and kite aerial photography, making it a rich destination for technically adventurous hobbyists.