Topic: Amateur radio
The AMPRNet (AMateur Packet Radio Network) or Network 44 is used in amateur radio for packet radio and digital communications between computer networks managed by amateur radio operators. Like other amateur radio frequency allocations, an IP range was provided in 1981 for Amateur Radio Digital Communications (a generic term) and self-administered by radio amateurs. In 2001, undocumented and dual-use of 18.104.22.168/8 as an internet telescope began, recording the spread of the Code Red II worm in July 2001.
- "AMPRNet: Amateur Packet Radio Network" | 2015-11-18 | 25 Upvotes 14 Comments
Balloon Experiments with Amateur Radio (BEAR) is a series of Canadian-based amateur radio high-altitude balloon experiments by a group of amateur radio operators and experimenters from Sherwood Park and Edmonton, Alberta. The experiments started in the year 2000 and continued with BEAR-9 in 2012 reaching 36,010 metres (118,140 ft).
The balloons are made of latex filled with either helium or hydrogen. All of the BEAR payloads carry a tracking system comprising a GPS receiver, an APRS encoder, and a radio transmitter module. Other experimental payload modules include an Amateur Radio crossband repeater, and a digital camera all of which is contained within an insulated foam box suspended below the balloon. A parachute recovery system is automatically deployed when the balloon bursts at altitude.
- "Balloon Experiments with Amateur Radio" | 2020-01-27 | 65 Upvotes 25 Comments
Heathkit is the brand name of kits and other electronic products produced and marketed by the Heath Company. The products over the decades have included electronic test equipment, high fidelity home audio equipment, television receivers, amateur radio equipment, robots, electronic ignition conversion modules for early model cars with point style ignitions, and the influential Heath H-8, H-89, and H-11 hobbyist computers, which were sold in kit form for assembly by the purchaser.
Heathkit manufactured electronic kits from 1947 until 1992. After closing that business, the Heath Company continued with its products for education, and motion-sensor lighting controls. The lighting control business was sold around 2000. The company announced in 2011 that they were reentering the kit business after a 20-year hiatus but then filed for bankruptcy in 2012, and under new ownership began restructuring in 2013. As of 2019, the company has a live website with newly-designed products, services, vintage kits, and replacement parts for sale.
- "Heathkit" | 2014-10-07 | 38 Upvotes 17 Comments
Olivia MFSK is an amateur radioteletype protocol, using multiple frequency-shift keying (MFSK) and designed to work in difficult (low signal-to-noise ratio plus multipath propagation) conditions on shortwave bands. The signal can be accurately received even if the surrounding noise is 10 dB stronger. It is commonly used by amateur radio operators to reliably transmit ASCII characters over noisy channels using the high frequency (3–30 MHz) spectrum. The effective data rate of the Olivia MFSK protocol is 150 characters/minute.
Olivia modes are commonly referred to as Olivia X / Y (or, alternatively, Olivia Y / X ), where X refers to the number of different audio tones transmitted and Y refers to the bandwidth in hertz over which these signals are spread. Examples of common Olivia modes are 16/500, 32/1000 and 8/250.
- "Olivia MFSK" | 2019-06-11 | 162 Upvotes 27 Comments