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://jap.hu/electronic/rf.html
Peter's RF schematics page is a technical reference collection of radio frequency circuit diagrams spanning receivers, transmitters, and transceivers across a wide range of frequencies from 27MHz to 1GHz. Hobbyists and engineers will find schematics for superregenerative receivers, FM audio transmitters, walkie-talkies, SAW-based designs, and datasheets for chips from major manufacturers like Silicon Labs, HopeRF, and Texas Instruments.
https://astrosystems.biz/
AstroSystems is a Colorado-based manufacturer selling telescope kits, accessories, and components including their signature TeleKit truss tube Dobsonians, secondary mirrors, laser collimators, and digital setting circles. With worldwide shipping and a broad catalog spanning fast f/ratio optics to dew removal systems, this site is a go-to resource for amateur telescope makers and Dobsonian enthusiasts.
http://zl2ctm.blogspot.com/
Charlie Morris (ZL2CTM) documents his amateur radio homebrew experiments on this technical blog, sharing detailed projects like a 40m Pelican Case SSB transceiver complete with Arduino code for LCD displays and Si5351 synthesizers. A great resource for ham radio enthusiasts interested in building their own transceivers and RF circuits from scratch.
http://mineralzine.chez.com/
Mineral Webzine is a bilingual French-English non-commercial online magazine dedicated to rockhounds, mineral collectors, and geology enthusiasts. Featuring photographs of specimens like garnet, wulfenite, and cinnabar contributed by collectors from Canada and France, it serves as a reference for mineralogy, crystallography, and gemology.
http://w0abr.com/
The Hub City Amateur Radio Club (W0ABR) serves the Aberdeen, South Dakota area with regular club meetings, nets, and informal coffee gatherings for ham radio enthusiasts. The site lists upcoming events, links to local APRS activity and weather resources, and connects members to the ARRL and regional repeater networks.
https://assa.org.au/
The Astronomical Society of South Australia (ASSA) is an active community organization offering public and member viewing nights, monthly meetings, and astronomy resources for all skill levels. The site features a rich collection of guides covering astrophotography, comets, variable stars, Aboriginal astronomy, and solar system events, plus details on observing sites like Stockport Observatory.
http://muzique.com/
Jack Orman's AMZ is a deep well of DIY guitar effects pedal knowledge, offering free schematics, project guides, a lab notebook, and a blog covering circuits for fuzzboxes, boosters, overdrives, and more. With decades of content, PCB boards for sale, and downloadable ebooks, it stands as one of the most comprehensive stompbox electronics resources on the old web.
http://rainreport.com/
RainReport.com offers a way to track and measure rainfall data without needing on-site monitoring equipment or physically visiting your property. The service uses Doppler radar and related data to provide precise rainfall reports, making it a practical tool for homeowners, farmers, and anyone who needs to know when and how much rain fell at a specific location.
https://wwcr.com/
WWCR is the official site for World Wide Christian Radio, a shortwave broadcasting station based in Nashville, Tennessee, operating four 100,000-watt transmitters across 10 channels to reach a global audience. Visitors can browse program schedules, listen online, find transmitter frequencies, and learn about buying airtime on one of the most powerful shortwave religious and talk radio broadcasters in North America.
https://msuarc.egr.msu.edu/
The MSU Amateur Radio Club (W8SH) has been connecting students to ham radio at Michigan State University since 1919, with roots tracing back to the founding of what would become WKAR public radio. The site offers club membership info, repeater details, and original tools like POTAVis and FoxHuntr built by club members to help hams visualize POTA activations and practice radio direction finding.