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://kc1xx.com/
KC1XX is the site for a competitive amateur radio station, featuring details about the station setup, antenna systems, and the team behind the operation. Visitors can browse the station gallery, search logs, and request QSL cards, with a bonus section covering the HJ4XX DX expedition.
https://aaroncake.net/circuits/index.asp
Aaron Cake's extensive collection of electronic circuit schematics covers categories from power supplies and light/laser projects to telephone circuits and sound/radio designs. Each circuit includes printable PCB patterns, community rankings, and user comments, making it a hands-on resource for hobbyist electronics builders.
https://circuitsarchive.org/
CircuitsArchive is a free, web-based archive of electronic circuit schematics covering everything from audio gear and battery monitors to filters, telephone interfaces, and microprocessor circuits. Maintained by Nicola Asuni since 1998, it offers a well-organized collection of PCB designs and projects useful to hobbyists and engineers alike.
https://rckara.org/
The RCKARA (likely Reno County Kansas Amateur Radio Association) maintains this site as a hub for their amateur radio club, featuring meeting minutes, hamfest announcements, and member activities. Visitors will find detailed records of club business including repeater trustee reports, WSPR balloon tracker experiments, and links to ARRL News and NOAA Space Weather.
https://britastro.org/useful-links
The British Astronomical Association, supporting amateur astronomers since 1890, maintains this curated directory of useful links covering UK astronomy societies, observing resources, and related organizations. Visitors will find connections to groups like the Society for Popular Astronomy, the Federation of Astronomical Societies, and many more resources spanning the full breadth of amateur astronomy.
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.
https://mdgeosociety.org/
The Maryland Geological Society is a non-profit club founded in 1991 for amateur and professional fossil and mineral collectors, open to all who share a passion for the geological sciences. Visitors will find meeting schedules, field trip announcements, fossil and mineral FAQs, a gallery, newsletter archives, and articles by contributing scientists.
http://magicrepeater.net/
The official web presence of M.A.G.I.C. (Minnesota Amateur Group of Independent Communicators), a ham radio club operating multiple repeaters across the St. Paul, Hugo, Foreston, and North Branch areas of Minnesota. Visitors will find repeater frequency details, band plans, ham radio links, scanner resources, shortwave links, DMR network info, and announcements for club tailgate events.
https://astronomy-links.net/lifeonwanderingplanets.html
Clark M. Thomas presents a speculative essay on the possibility of life on wandering planets and dark solar systems, drawing on extremophile biology and decades of independent astronomical thinking. The piece weaves together astrophysics, astrobiology, and theology, touching on exoplanets, Europa, HIV research history, and UFOs as part of the author's idiosyncratic intellectual journey.
https://qsl.net/lu2ee
A QSL.net-hosted page for the amateur radio callsign LU2EE, indicating an Argentine ham radio operator with a personal station page. The site appears to be a file directory index, likely containing logs, images, or station information typical of ham radio operator pages on the QSL.net network.