Science & Nature
1439 sites
Subcategories:
- Astronomy & Space (396)
- Chemistry (8)
- Earth Sciences (26)
- Biology (79)
- Physics (30)
- Mathematics (59)
- Weather & Climate (104)
- Amateur Radio (682)
- Electronics (47)
https://www.qsl.net/kb4kvt/index.htm
KB4KVT is a personal amateur radio homepage featuring the callsign of a licensed ham operator, with imagery of an Eimac 4-1000 transmitting tube hinting at high-power RF interests. The site serves as a landing page for a ham radio enthusiast, likely covering equipment, operations, or related technical topics.
http://rxcontrol.free.fr/
A technical hobbyist site focused on shortwave listening, featuring custom hardware designs using PIC microcontrollers, RTTY decoders, HF receiver control software, and digital decoding tools built by the creator. Visitors will find schematics, software downloads, and detailed projects spanning everything from RS-232 adapters to ADS-B decoders and frequency standards.
https://daviddarling.info/encyclopedia/A/40_Eridani.html
David Darling's encyclopedia entry on 40 Eridani covers the nearby trinary star system in Eridanus, including its white dwarf, red dwarf, and orange main-sequence components, with detailed discussion of habitability and its famous role as Vulcan's star in Star Trek. Part of a broader astronomy encyclopedia, this page blends rigorous stellar data with engaging science fiction connections, complete with NASA imagery and comparisons to our own solar system's habitable zone.
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://swling.com/blog
The SWLing Post is a richly detailed blog dedicated to shortwave listening, ham radio, DXing, and all things radio, run by Thomas and a community of contributors. Visitors will find equipment reviews, broadcast schedules, numbers station reports, SDR guides, and news spanning pirate radio to vintage receivers.
https://f4iha.fr/
The blog of Olivier (F4IHA), a French amateur radio enthusiast who documents his homebrew radio projects including low-power QRPP transmitters, VFOs, antenna tuners, and fox-hunting modules built with Arduinos and components costing under 30 euros. Posts cover schematics, PCB design in KiCad, measurements, and hands-on construction with detailed technical write-ups that make it a great resource for DIY radio builders.
http://yearinspace.com/the-week-in-space
The Year In Space is a weekly online calendar that highlights space history, sky events, and astronomical milestones, pairing each entry with detailed write-ups and NASA imagery. Each week features a featured topic such as the discovery of Ceres or the Cassini mission, alongside a day-by-day calendar of notable birthdays, launches, and celestial events.
http://bratsatv.org/
The Baltimore Radio Amateur Television Society (BRATS) is a non-profit amateur radio club based in Baltimore, Maryland, focused on ATV (amateur television) repeaters, emergency communications, and public service. The site features club news, meeting announcements, technical writeups on their ATV repeater revival project, and information on joining the organization.
https://math.cowpi.com/
Math @ CowPi offers a curated collection of math tools and resources, including interactive GeoGebra sketches, a system-of-equations solver for up to five unknowns, and a full annotated text of Edwin A. Abbott's classic novel Flatland. Visitors will also find organized math links spanning algebra, geometry, trigonometry, and calculus, making it a handy reference for students and enthusiasts alike.
http://members.chello.at/natura/shrew/index.html
Created by Werner Haberl, this scholarly hub is dedicated entirely to the biology of shrews (Soricidae), featuring a bibliography, photo gallery, newsletter, congress announcements, and a forum for zoologists worldwide. Awarded 'Coolest Science Site' in 1996 and mentioned in BBC Wildlife Magazine and Encyclopedia Britannica Online, it remains a remarkably deep and specialized resource for both researchers and curious naturalists.