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)
http://sss-mag.com/smith.html
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.
http://rfchoke.com/
A technical reference site dedicated to RF chokes, ferrite cores, and related radio frequency electronics components used in amateur radio and RF engineering applications. Visitors will find practical information on choke design, impedance characteristics, and suppression of common-mode currents on antenna feedlines.
https://www.qsl.net/ccac
The Capital City Amateur Club (CCAC) is a ham radio club based in the Baton Rouge, Louisiana area, home to the W5KRO callsign and their repeater systems. Visitors will find links to local 2-meter and 70cm repeater lists, Baton Rouge area nets, ham equipment manufacturers, dealers, and a photo gallery featuring their tower and antenna projects.
https://ai5.mx/
Michael Burkhardt (AI5MX) runs this personal ham radio blog covering gear reviews, operating logs, QSL cards, Morse code adventures, and FCC news. Visitors will find mirrored Mastodon microposts, downloadable resources, and a genuine indie-web spirit connecting the amateur radio community.
https://front.emilkirkegaard.dk/
Emil O. W. Kirkegaard is a quantitatively minded researcher whose personal site serves as a hub for his extensive academic publications covering psychometrics, intelligence research, behavioral genetics, and population studies. The site lists dozens of peer-reviewed papers published in journals like Comparative Sociology and OpenPsych, alongside links to his English and Danish blogs and YouTube channel.
http://skymaps.com/
Skymaps.com, created by Kym Thalassoudis, offers free monthly sky maps and star charts in PDF format to help amateur and professional skywatchers explore constellations, planets, and comets. The site also features a curated store with planispheres, star atlases, telescopes, and astronomy books for all skill levels.
http://nrrt.org/
The Newton Radio Response Team is a community emergency communications group based in Newton, likely coordinating amateur radio operators for public safety and disaster response. Sites like this serve as a hub for volunteer ham radio operators who support local emergency services when standard communications fail.
http://sguisard.astrosurf.com/
Stéphane Guisard's personal astrophotography showcase, 'Los Cielos de América,' features stunning celestial imagery captured from the Americas and beyond. The image-heavy site is a visual feast for astronomy enthusiasts, presenting the night skies through the lens of a dedicated and skilled astrophotographer.
http://wikisky.org/
WikiSky.org is an interactive online sky map that lets users explore stars, galaxies, nebulae, and constellations through a virtual telescope interface with support for over 15 languages. The platform combines user-contributed content with professional astronomy data, featuring astro photography, science news, blogs, and a community forum for stargazers worldwide.
https://oeis.org/
The OEIS is a massive searchable database of over 393,000 integer sequences, maintained by the OEIS Foundation and originally created by mathematician Neil Sloane. Researchers, students, and math enthusiasts can look up sequences by entering numbers to identify patterns, explore combinatorics, and discover connections across mathematical disciplines.