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://ptri1.tripod.com/
A detailed educational resource dedicated entirely to Pascal's Triangle, covering its construction, history, and the surprising number of patterns hidden within it. Visitors can explore topics ranging from the Fibonacci sequence and Sierpinski fractals to prime numbers and polygonal numbers, with downloadable programs to generate and visualize the triangle's patterns.
https://sarts.org.sg/
The Singapore Amateur Radio Transmitting Society (SARTS) is the national organization for ham radio enthusiasts in Singapore, offering resources on licensing, frequency bands, and getting started with amateur radio. The site features news posts on topics like FreeDV signals, web SDRs, and satellite launches, along with a marketplace, gallery, and membership information for the local ham community.
https://w7eca.org/
The Great Falls Area Amateur Radio Club (W7ECA) is a ham radio club serving operators in Cascade County and surrounding North Central Montana. The site covers club membership, repeater information, ARES emergency communications, and events like Field Day and the historic Glacier Waterton Hamfest.
http://big.or.jp/~ham/dx.html
A long-running DX information hub operated by Waiwai Ham Life, aggregating 50MHz DX cluster data from Japan with archives stretching back to 1998. The site covers HF DX, EME, 144MHz, and satellite contacts, and includes links to callbooks, DXCC lists, IOTA lists, and logging software for serious DXers.
http://wxqa.com/
The Citizen Weather Observer Program (CWOP) is a public-private partnership that collects weather data from over 7,000 citizen-operated stations across North America, feeding real-time observations to NOAA and dozens of government agencies. Visitors can join the network, check data quality, view maps and displays, and access resources for setting up their own personal weather stations.
http://ibiblio.org/pub/academic/agriculture/agronomy/ham/BOATANCHORS
Hosted on ibiblio, this is an archive of the Boatanchors mailing list digests, covering vintage and antique radio equipment collecting and restoration. The archive spans hundreds of digest issues alongside FAQs, welcome files, and supplementary resources for enthusiasts of classic tube-based radio gear.
https://johnshepler.com/articles/piday.html
John Shepler's engaging article celebrates Pi Day and explores the fascinating history of the transcendental number pi, from ancient scholars to modern supercomputers crunching billions of decimal places. Packed with fun facts, literary references, and links to birthday calculators and playlists, it makes mathematics genuinely entertaining for casual readers and math enthusiasts alike.
https://felderbooks.com/papers/godel.html
Kenny Felder offers a thorough and accessible explanation of Gödel's Incompleteness Theorem, drawing heavily on Hofstadter's 'Gödel, Escher, Bach' to walk readers through the mathematics and philosophy behind one of the most profound results in logic. Written in 1996, the piece explores formal axiomatic systems, Russell and Whitehead's Principia Mathematica, and the far-reaching implications of Gödel's work for mathematics, artificial intelligence, and the nature of mind.
https://qsl.net/rz1ak/mail.html
The personal ham radio page of RZ1AK, a Russian amateur radio operator, featuring information on how to send letters and QSL cards to Russia. Hosted on the classic QSL.net network, this page offers a glimpse into the international correspondence culture of the ham radio community.
https://w6ka.net/
The Pasadena Radio Club (W6KA) is a Southern California ham radio club offering meetings at Kaiser Permanente in Pasadena with simultaneous Zoom access, plus contests, Field Day events, and local repeater information. The site features a bulletin archive, event calendar, membership resources, and a library of reference materials for both newcomers and experienced amateur radio operators.