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://damtp.cam.ac.uk/user/tong/teaching.html
David Tong, a professor at Cambridge University, offers a comprehensive collection of free lecture notes covering nearly every area of theoretical physics, from classical mechanics and electromagnetism to quantum field theory and string theory. The notes are aimed at undergraduates and graduate students and represent a genuinely deep academic resource, with dozens of individual courses each spanning multiple topics.
![Hurricane Forecast Model Output :: [Main]](/screenshots/26361.webp)
https://web.uwm.edu/hurricane-models/models
Hosted at the University of Wisconsin-Milwaukee, this site by Clark Evans provides hurricane forecast model output for the North Atlantic, Eastern Pacific, and Central Pacific basins. It offers an archive, storm identifiers, shapefiles, KML data, analogs, and verification tools, making it a technical reference for tracking tropical storm activity.
https://radioring.neocities.org/
The Radio Ring is a Neocities-based webring connecting personal websites whose owners share a love of radio, welcoming both amateur radio enthusiasts and casual fans alike. Built on the onionring framework, it offers simple join instructions and links members together in a navigable loop.
https://www.qsl.net/lz1iii/html/1001link.html
A massive curated directory of amateur radio links maintained by LZ2HM, covering everything from ARRL resources and antenna plans to SSTV, ATV, antique radios, aurora monitoring, and weather resources. With over 1,300 links organized into dozens of categories, it serves as a comprehensive reference hub for ham radio operators of all interests.
http://ben.davies.net/telescope.htm
Ben Davies documents the design and construction of a 12.5-inch Newtonian telescope, covering everything from the equatorial horseshoe mount and mirror flotation cell to motorized collimation and CCD imaging. The site also includes observational work on variable stars, nebulae, galaxies, and spectroscopy, making it a rich resource for serious amateur telescope makers.
http://ncrg.org.au/
The Northern Corridor Radio Group (NCRG) is an amateur radio club based in Whiteman Park, Perth, Western Australia, operating callsigns VK6ANC, VK6NC, and VK6NE across contests and regular on-air activity. The site covers club meetings, licensing courses, exams, repeater status, construction projects, and events like the annual Hamfest and carboot sale.
https://deepskyorg.tripod.com/deepsky_quiz.html
Deep-Sky.Org hosts an interactive quiz testing visitors' knowledge of deep-sky objects such as nebulae, galaxies, and star clusters. The multiple-choice format makes it a handy study tool for amateur astronomers looking to sharpen their observational knowledge.
https://hypertextbook.com/chaos
The Chaos Hypertextbook is a deep educational resource covering chaos theory, fractals, strange attractors, and fractal dimension with clear explanations aimed at making complex mathematics accessible to a broad audience. Organized into chapters covering iteration, bifurcation, Julia sets, Mandelbrot sets, and nonlinear dynamics, it reads like a beautifully structured online textbook that would captivate anyone curious about the mathematics underlying unpredictable systems.
https://k3lr.com/
K3LR is the homepage of Tim Duffy's world-class amateur radio contest station, featuring a multi-operator, multi-transmitter setup that has been featured in QST, RadCom, and the Spectrum Monitor. The site showcases Team K3LR's competition activities, sponsored equipment from Icom and DX Engineering, and links to Dayton Contest University events.
https://yb0ah.tripod.com/
H.K. Ardiwinata (YB0AH) built this Indonesian amateur radio resource covering homebrew electronics, circuit diagrams, and equipment manuals collected from personal experience and other ham radio sites. It features sections on basic electronics, ham equipment manuals, and electronics circuit diagrams, making it a useful reference for Indonesian ham radio enthusiasts.