Ham Radio For Dummies. H. Ward Silver
Чтение книги онлайн.
Читать онлайн книгу Ham Radio For Dummies - H. Ward Silver страница 14
Mobile and boating: Hams operate while on the road or on the water, fresh or salt. They like to stay in touch during their travels and other hams like to contact them as they visit unusual locations. If there are mechanical problems, the station has a ready group of helpers. When there’s no phone service or Internet, such as at sea or in remote locations, the net can relay messages and status reports.
Digital networks:Messaging: Ham radio was the original “text messaging” system and we’re still pretty good at it! Not only do hams exchange messages directly between stations, they have built relay networks, such as APRS (discussed earlier in this chapter), D-RATS, WSPR, and many more.Email: If you could listen to Internet systems make contact and exchange data, a “mailbox” station might be what they’d sound like. Mailbox stations monitor a single frequency all the time so that others can connect to it and send or retrieve messages via the ham radio Winlink system (www.winlink.org
).High-speed data: Hams share access to frequencies used by WiFi and similar services. By reprogramming common routers and other network equipment, hams have created their own high-speed networks, such as HSMM-MESH and the Amateur Radio Emergency Data Network (AREDN). The repurposed routers listen for other routers nearby and connect to them, forming an “ad hoc” network. These flexible network can also connect to the Internet and are a valuable public service tool, especially in remote areas without reliable mobile phone service.
Citizen Science and HamSCI
Hams have supported “real science” since the earliest days of wireless when everyone was an experimenter. One of the best examples is the series of “listening tests” conducted during the early 1920s, in which hams supplied many observations that helped establish the existence of the ionosphere. Amateur radio and science have gone hand-in-hand ever since. The ARRL publication A History of QST, Volume 1: Amateur Radio Technology describes the 100-year story of collaboration between hams and scientists, discovering and inventing technologies at the foundation of our present-day wireless world. Ham radio is also a great activity for STEM (science, technology, engineering, and math) students in secondary or university-level education. The hands-on nature of ham radio makes the equations and graphs “real.” Ham radio provides practical experience with all sorts of know-how that is offered by few other activities.
Today, there are opportunities for hams to participate in scientific research. These are just a few of the opportunities hams have to make real contributions:
High-altitude ballooning: Student teams and individuals launch weather balloons with APRS equipment (described earlier in this chapter) to track the balloon position and altitude. Data and images are either transmitted back to the ground or stored on a memory card and recovered along with the balloon. Find out more about amateur high-altitude ballooning at www.arhab.org
.
CubeSats: Working with universities and government space programs, teams of students and researchers build micro-scale satellites (www.cubesat.org
) that beam telemetry data from on-board experiments back to Earth. Some satellites also have simple repeater or translator stations on-board that hams can use for point-to-point communication.
Society of Amateur Radio Astronomers (SARA): If keeping an eye on the sky sounds interesting, check out the SARA website (radio-astronomy.org
). It can help you build your own equipment, find kits, or purchase preassembled gear.
WSPRnet: A special digital protocol, WSPR was designed to make measurements of propagation using extremely low power. To collect the observations, WSPRnet was created (wsprnet.org
) with stations reporting in world-wide, 24 hours a day. The data is used for modeling the ionosphere, examining the effect of solar activity, and making propagation predictions.
In August of 2017, the United States was treated to a coast-to-coast total solar eclipse. Hams realized this would have a big effect on the ionosphere as the solar shadow traveled west to east. Because the ionosphere reflects shortwave signals, those signals could be used to measure the effect of the eclipse. HamSCI (www.hamsci.org
) was created to conduct the experiment, inviting hams to participate in a large-scale experiment to characterize the ionosphere’s response to the eclipse and other open scientific questions. Hundreds of hams helped out by getting on the air during the Solar Eclipse QSO Party (SEQP — see Figure 1-2), a contest-like operating event designed to generate data for studying the eclipse.
[Ann Marie Rogalcheck-Frissell, KC2KRQ, photo]
FIGURE 1-2: Students from the New Jersey Institute of Technology club (K2MFF) operating during the eclipse.
The success of the SEQP both in the number of observations and their high quality, led the group to create today’s forum for academic and other professional researchers to engage the ham radio community. Today’s HamSCI features a wide range of researchers and interested amateurs. Check out the group’s projects and events if you’re interested in using ham radio to advance science — any interested person is welcome. And there’s another total solar eclipse traversing the United States from south to north in 2024!
Chapter 2
Getting a Handle on Ham Radio Technology
IN THIS CHAPTER
Getting familiar with ham radio gear
Discovering radio waves
Understanding the effects of nature on ham radio
Ham radio covers a lot of technological territory — one of its most attractive features. To get the most out of ham radio, you need to have a general understanding of the technology that makes ham radio work.
In this chapter, I cover the most common terms and ideas that form the foundation of ham radio. If you want, skip ahead to read about what hams do and how we operate our radios; then come back to this chapter when you need to explore a technical idea.
Getting to Know Basic Ham Radio Gear
For some hams, their entire station consists of a small handheld radio or two. Other hams operate on the go in a vehicle. Most hams also have a spot somewhere at home that they claim for a ham radio and associated gadgets. I discuss building and operating your own station in Part 4 of this book. You can see examples of several stations, including mine, in Chapter 13. For now, though, here’s a list of the usual gear that makes up a ham’s station:
The radio: The modern radio