Ham Radio For Dummies - H. Ward Silver

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you make contacts for different purposes, most contacts follow the same structure:

      1 You make a call to someone or respond to someone else’s call by transmitting your call sign over the air.

      2 You and the other operator exchange names, information about where you’re located, and the quality of your signals for an understanding of conditions between your stations.

      3 If the purpose of the contact is to chat, proceed to chat.You might talk about how you constructed your station, what you do for a living, your family, and your job, for example.

      

A call sign, often shortened to just call, is a ham’s “radio name.” (The term call letters is only used by broadcast radio and TV stations.) Call signs have two parts; a prefix of letters and a number, such as KE7 or W5, and a suffix, which is all letters. The prefix tells you what country licensed the ham and the suffix tells you which ham it is. My call, NØAX, says “N” (so I’m American), “Ø” (so I was licensed in the tenth call district), and “AX” (that’s me!). Chapter 7 covers call signs in detail.

      

A question that I’m frequently asked about ham radio is “How do you know where to tune for a certain station?” Usually, my answer is “You don’t!” Ham radio operators don’t have specific frequency assignments or channel numbers. This situation is a good news/bad news situation. The good news is that ham radio gives you unparalleled flexibility to make and maintain communications under continually changing circumstances. The bad news is that making contact with one specific station requires you to know when and on what frequency to call. As you see in Chapter 11, hams have found many ways to solve this problem, however; the result is an extraordinarily powerful and adaptive communications service.

      Ragchews

      By far the most common type of activity for hams is casual conversation, called chewing the rag. Such contacts are ragchews. Ragchews take place via voice or keyboards or Morse code across continents or across town. You don’t have to know another ham to have a great ragchew; ham radio is a friendly hobby with little class snobbery or distinctions. Just make contact, and start talking! Find out more about ragchews in Chapters 8 and 9.

      

The origins of the word ragchew are fairly clear. The phrase chewing the rag was well known even in the late Middle Ages. Chew was slang for talk, and rag, derived from fat, was a reference to the tongue. Thus, people began to use chewing the rag to describe conversations, frequently those that took place during meals. Later, telegraph operators picked up that use, and hams picked it up from telegraphers. Because most of ham radio is in fact conversation, ragchewing has been part of radio since its earliest days.

      Nets

      Nets (an abbreviation of networks) are organized on-the-air meetings scheduled for hams who have a shared interest or purpose. Your club or public service team probably has a regular net on a weekly basis. These are great practice for new hams! Here are some of the types of nets you can find:

       Public service: Under normal circumstances, these nets meet for training and practice. When disasters or other emergencies strike, hams organize using these nets to provide crucial communications into and around the stricken areas until normal services are restored. The nets are also used to provide non-emergency assistance to public events, like parades or foot races.

       Technical specialties: These nets are like radio call-in programs; stations call in with specific questions or problems. The net control station may help, but more frequently, one of the listening stations contributes the answer. Many technical-assistance nets are designed specifically to assist new hams.

       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.

      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

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