Ham Radio For Dummies - H. Ward Silver

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       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.

Photo depicts students from the New Jersey Institute of Technology club (K2MFF) operating during 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.

      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.

       The radio: The modern radio transceiver, also referred to as a “rig,” combines a receiver and transmitter in a single compact package about the size of an average home entertainment receiver. Transceivers usually have a large tuning knob that controls the frequency, but computer-style displays and screens have replaced the dials and meters of older gear. Today’s software-based radios use a PC or tablet for controls and displays.

       Computer: Most hams today have at least one computer in the station. Computers can control many of a radio’s functions. Using most digital signals simply wouldn’t be possible without them. Hams often use more than one computer at a time to perform different functions. Accessories and gadgets using Arduino and Raspberry Pi computers are quite common. Software allows you to control the operating frequency and many other radio functions from a keyboard. Computers can also keep your log, a record of your contacts. Computers can send and receive Morse code, too.

       Handheld radio: Popular with new hams, a handheld transceiver is a convenient way to get started making contacts through local repeaters. Battery-powered, these radios can be used in a vehicle or any time you are away from your home station.

       Mobile/base radio: These radios are used for regular mobile operation and in home stations. They produce much more output power than the small handheld models and are about the size of a mid-sized hardcover book.

       Microphones, keys, and headphones: Depending on the station owner’s preferences, you’ll see a couple (or more) of these important gadgets, the radio’s original user interface. Microphones and keys range from imposing and chrome-plated to miniaturized and hidden. The old Bakelite headphones, or cans, are also a distant memory (which is good; they hurt my ears!), replaced by lightweight, comfortable, high-fidelity designs.

       Antennas: In the station, you’ll find switches and controllers for antennas that live outside. A ham station tends to sprout antennas ranging from thin whips the size of pencils to wire antennas stretched through the trees and supersized directional beam antennas held high in the air on steel towers. See Chapter 12 for more info on antennas.

       Cables and feed lines: Look behind, around, or under the equipment and you find wires. Lots of them. The radio signals are piped through thick, round coaxial cables, or coax. Power is supplied by wires not terribly different in size from those that power a car stereo. I cover cables and feed lines in detail in Chapter 12.

      Although the occasional vintage vacuum-tube radio still glows in a ham’s station, today’s ham radios are sleek, microprocessor-controlled communications centers, as you see in this section.

      

Ham stations are often referred to as a radio shack. That’s an old term from the very early days of radio when noisy and somewhat dangerous equipment was used. As a result, the station was often in a small shed of its own — literally a shack! Today, your “shack” is simply the place you keep your radio and other ham equipment. The days of bulbous vacuum tubes, jumping meters, and two-handed control knobs are largely in the past.

      Basic stations

      The stations shown here are very versatile — they can be used as a home or base station, a mobile station in a vehicle, or as a portable station. Equipment is available for very lightweight, low-power

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