Deciding what you want to do

You can find many activities in ham radio, which I cover in Part 3. You can use the same equipment to participate in most of them. Before you start acquiring equipment, decide what you want to do with it by answering these questions:

• What attracted you to ham radio?
• Can you pick two or three operating activities, styles, or modes that really pique your interest?
• If you know and admire a ham, does he or she do something that you want to do?
• Are you most attracted to the shortwave bands or to the VHF and UHF bands?
• What sounds most intriguing: Using the digital modes, chatting by voice, mastering Morse code, exchanging images?
• Are you interested in a special type of contact, such as satellite or DX or meteor scatter?
• Will you operate with home, mobile, or portable equipment (or all three)?
• Do you intend to participate mainly for enjoyment or for a specific purpose, such as public service or travel communications?

All these considerations affect your choice of equipment.

Knowing your ham radio resources is also important. Answer these questions:

• What’s your budget for getting on the air?
• How much space do you have available for your station?
• How much space do you have for antennas?
• Do you have restrictions in your property deed or rental/lease agreement on transmitting or putting up antennas?

The following sections help you determine what your options are.

Deciding how to operate

The first decision to make is where you expect to operate your station most of the time — at home, in a car, or in a backpack, for example. This choice determines the size and weight of the equipment, what kind of power source it needs, and the type of antennas you’ll be using. All those characteristics have a big effect on what features and accessories you’ll want and need.

Allocating your resources

When you start assembling a station, you have a range of items to obtain — not only the radio itself, but also antennas, accessories, cables, and power sources. Table 12-1 shows some comparisons of relative costs based on the type of station you’re setting up. If you pick a radio first, the remaining four columns give you a rough idea of how much you should plan on spending to complete the station. These figures are approximate but can get you started. I assume that all the gear is purchased new.

For digital mode operating, you usually need some kind of computer and an interface between it and the radio. This job is perfect for that old computer. The interface allows you to connect the computer’s sound card to the microphone input and speaker output. (Also see “Choosing a Computer for the Station,” later in this chapter.)

Radios for the HF bands

All modern radios have perfectly usable receive and transmit performance. The differences involve performance in several key areas, such as capability to receive in the presence of strong signals, signal filtering, coverage of one or more VHF/UHF bands, operating amenities such as sub-receivers, and whether a built-in antenna tuner is available.

HF radios for the home station fall into three categories:

• Basic: This radio has a simplified set of controls with basic receiver filters and signal adjustments. Controls may be fixed-value, with on and off settings. The radio has limited displays and metering, connects to a single antenna, and has minimal support for external accessories. A basic radio is good for a beginning ham and makes a great second or portable radio later.
• Standard: This radio includes all the necessary receive and transmit adjustments. It has front-panel controls for incremental tuning (fine tuning) plus filter selection and adjustment. It has an expanded set of memory, display, and metering functions. You can find models that have additional bands and direct connections for digital operation. Internal antenna tuners are common. Many radios have “accessory” connectors for external equipment, such as data interfaces and band-switching equipment.
• High-performance: This radio has a extensive receive and transmit controls on the front panel. Some controls are configurable via a menu system. These radios have band-scope, panadapter, or waterfall displays that show signals across a wide frequency range. A state-of-the-art receiver and subreceiver are included, along with complete interfaces for digital modes. Internal antenna tuners are standard, and some antenna switching usually is provided.

The major ham radio dealers have organized their catalogs and websites to help you find a capable radio at a price that fits your budget. Start online, collecting information on the radios you like; then head for the product review sections of eHam.net and QRZ.com. Your club members may have some opinions as well.

ARRL members have access to the detailed product reviews published in QST, including complete technical evaluations by the ARRL Lab. The reviews cover everything from top-of-the-line transceivers to microphones and power supplies.

VHF and UHF radios

VHF/UHF radios that operate in single sideband (SSB), Morse code (CW), and FM modes are known as all-mode or multimode to distinguish them from FM-only radios. Many of the VHF/UHF all-mode radios have special features, such as full duplex operation and automatic compensation for transponder offsets, that make using amateur satellites easier. (I introduce amateur satellite operation in Chapter 11.) Satellite operations require special considerations because of the need for cross-band operation and the fact that satellites are moving, which results in a Doppler shift on the received signal.

An all-mode radio can also form the basis for operating on the amateur microwave bands. Commercial radios aren’t available for these bands (900 MHz; 2.3, 3.4, 5.6, 10, and 24 GHz; and up), so you can use a transverter instead. A transverter converts a signal received on the microwave bands to the 28, 144, or 440 MHz band, where the radio treats it just like any other signal. Similarly, a transverter converts a low-power (100 milliwatts or so) output from the radio back up to the higher band. Bringing the output signal up to 10 watts or more requires an external amplifier.

Some “all-band” HF/VHF/UHF radios include 50, 144, and 440 MHz operation. The Kenwood TS-2000 and Icom IC-9100 can go all the way to 1200 MHz by adding an accessory module. This power makes purchasing a second radio just for VHF/UHF operating less a necessity for the casual operator. It’s common to have an all-band HF/VHF/UHF radio backed up with a VHF/UHF FM rig for using the local repeaters.

Mobile and handheld FM radios

Many hams use FM on the VHF and UHF bands regardless of their favorite operating style or mode. A newly minted Technician licensee likely uses an FM mobile or handheld radio as a first radio. FM is available on the all-mode rigs, but because of the mode’s popularity and utility, FM-only rigs are very popular.

FM radios come in two basic styles: mobile and handheld, as shown in Figure 12-1. Although they are intended for use in vehicles, you can use them rigs as base stations at home, too. Both mobile and handheld radios offer a wide set of features, including loads of memory channels to store all your region’s repeater information, powerful scanning modes, and several types of squelch systems.

I suggest that you start with a mobile radio shared between your car and your home. Assuming you live in an area with average or better repeater coverage, you can simply put a magnet-mount (mag-mount) antenna on top of the refrigerator and you’re in business. (If you live in a rural area, you probably need an outdoor antenna.) The stronger signal from the mobile allows you to operate successfully over a wider range, which is important at first. When you know more about what type of FM operating you want to do, you can buy a handheld radio with the right features and save money.

The more-powerful mobile transceivers used with an external antenna extend your range dramatically. Receivers in mobile radios often have better performance than those in handheld radios; they’re capable of rejecting the strong signals from commercial transmitters on nearby frequencies. Information about how receivers perform in such conditions is available in product reviews. Your own club members may have valuable experience to share, because they operate in the same places as you.

If you are part of a public service team, ask what type of radios are popular with the group members. That model would be a good first choice because they can help you learn how to use it and share their programming choices.

You can use mobile radios for digital data operation on the VHF/UHF bands, such as packet radio and APRS as discussed in Chapter 11. The most common setup was shown in Chapter 2 — the radio connects to an external data interface which is connected to a computer. For packet (which includes APRS and Winlink system connections), this interface is called a terminal node controller, or TNC. Radios that support D-STAR and other digital voice modes also have a digital interface that connects directly to the computer.

A rig that’s APRS-enabled can connect to (or may include) a GPS receiver and transmits your location, as described in Chapter 11. These radios are also useful for navigation and geocaching.

As radio modem technology has advanced, hams have begun to use 9600-baud data. If you plan to use your mobile rig for digital data, make sure that it’s data-ready and rated for 9600 baud without modification. These radios have an discriminator output (sometimes labeled DISC). This input is the unfiltered output of the FM demodulator. External equipment can use this signal both to indicate tuning and to receive data.

You can expect the radio to include as standard features encoding and decoding of CTCSS subaudible tones (tones used to restrict access to analog repeaters), variable repeater offsets, dozens of memory channels, and a numeric keypad. Digital voice radios include the majority of the digital system features.

Extended-coverage receiving is a useful feature. I find it very useful to listen to commercial FM broadcast and the National Weather Service (NWS) weather alert stations at 162 MHz (www.nws.noaa.gov/os/marine/wxradio.htm).

Programming a radio with dozens (if not hundreds) of memory channels can be a chore if you do it all with the front-panel controls. Most manufacturers offer free or low-cost programming software that connects to the radio with an optional cable. The software package CHIRP (chirp.danplanet.com/projects/chirp/wiki/Home) is a free, open-source programming tool, and RT Systems (www.rtsystemsinc.com) offers comprehensive packages including cables — both support numerous radios.

Ask around in your club to see if someone has programming software and a cable to connect your radio to a computer; you’ll be really glad you did. The software enables to you to quickly set up your radio for the local repeaters and simplex channels, including alphanumeric labels for each channel, if your radio supports that feature.

DMR (Digital Mobile Radio) system radios are programmed by loading them with a set of data called a code plug. (The term originated back when an actual special plug was required to program a radio.) Data in the code plug is transferred from a computer over a USB or proprietary interface. Be sure to get the necessary cable with your radio.

Most radios can also be cloned, meaning that you can transfer the contents of one radio’s memories to another radio of the same model by using a cloning cable. This method can save a lot of time if you buy a new radio and a friend has the same model already programmed.

HANDHELD FM RADIOS

Handheld radios come in single-band, dual-band, and multiband models. With the multiband radios covering 50–1296 MHz, why choose a lesser model? Expense, for one thing. The single-band models, particularly for 2 meters, cost less than half the price of a multiband model. You’ll do the lion’s share of your operating on the 2 meter (VHF 144–148 MHz) and 70 cm (UHF 420–440 MHz) bands, so the extra bands may not get much use.

Inexpensive handhelds made in China are becoming very common and very popular due to the low price. Before you buy one, check out its ARRL Product Review. These radios are often adaptations of models made for Land Mobile Radio or LMR use (a commercial/public-safety service, often referred to as Part 90 for the section of the FCC rules that apply). Some of the radios have been found to have poor output signal quality. Be sure the radios are found to have met the specifications for amateur radio use. Your public-service team may have the latest information.

A rechargeable battery and simple charger come with the radio. Be sure to get a spare battery and the base charger, if your budget allows. Other useful accessories include a full-size whip antenna, adapters for connecting external antenna cables, battery packs that accept standard AA or AAA batteries, speaker-mike combinations, and earphones.

Software-defined radio

The software-defined radio (SDR) in which most of a radio’s functions are implemented by digital signal processing (DSP) software is one of the most significant changes in ham radio technology since the transistor; I predict that it will largely displace traditional analog radio construction by 2020.

Digital signal processing (DSP) refers to a microprocessor in the radio running special software that operates on, or processes, incoming signals. The most advanced DSP operates on the signals at radio frequencies. This is called direct sampling. In general, the higher the number of bits specified for DSP and the higher the frequency at which the DSP functions are performed, the better the DSP processing performs. (Look in the radio’s operating manual or product specification sheet for more information.)

In an SDR, except for the receiver input and transmitter output circuits, the signal-handling part of the “radio” is a program. You can change the program any time you want to make the SDR do something else. A manufacturer can upgrade your equipment with new software just like a new operating system version on your phone.

In an SDR, after a some filtering and conditioning, the incoming radio signal is converted to digital data. From there, the signal is all data until it’s converted back to audio for the operator or to data characters for a computer. Going the other way, the outbound signal only needs to be amplified before being applied to the antenna and radiated into space.

As of late 2017, several SDR ham radio transceivers are available, and hams are finding the latest models to be strong performers. FlexRadio’s FLEX-6000 series (www.flexradio.com), shown in Figure 12-2, is the latest in the company’s SDR line of equipment. The popular IC-7300 is a completely standalone SDR packaged like a traditional transceiver but with all the SDR flexibility and functions. Manufacturers like Apache Labs (apache-labs.com), ELAD (ecom.eladit.com), and Expert Electronics (eesdr.com/en) are announcing new models of SDR and more are appearing every day. There are many receive-only SDRs, even built into USB thumb-drive “stick” packages.

A typical SDR displays signals across a frequency range as in the top of the figure. This display is called a panadapter view. Below it is the waterfall display, with colors that show which signals are strongest over time. You use a mouse to select signals and click operating controls. (See the discussion of software like DigiPan and FLDIGI in Chapter 11 for more about these types of displays.)

Hams are just beginning to scratch the surface of what SDR can do. All that data onscreen can just as easily be passed to more programs. What will hams do with it? Nobody knows yet. It’s an exciting time for ham radio!

Filtering and noise

After sensitivity, the ability to pick up a weak signal, the most important capability for a receiver is distinguishing one signal from another. This is called selectivity. Receivers use filters to remove unwanted signals from interfering with the one you want to receive while attenuating (reducing the strength of) unwanted signals just a few hundred hertz away. The range of frequencies that are passed is the filter’s bandwidth, measured in hertz or kilohertz. Filters that remove a range of frequencies are called band-reject filters. If the range of rejected frequencies is very narrow, the filter is a notch filter.

For many years, radios used crystal filters made of quartz crystals. Crystal filters have a fixed bandwidth, and most can’t be adjusted.

Current mid-level and high-end radios use DSP technology to perform filtering in software. The bandwidth of DSP filters is adjustable, which allows you to use just the right amount of filtering. DSP can also perform filtering functions to remove off-frequency signals, reduce or eliminate several kinds of noise, or automatically detect and remove interfering tones.

Radios often use fixed-width roofing filters that help the receiver reject extremely strong signals often encountered on busy bands or near shortwave broadcast stations. If roofing filters are available for your radio, purchasing one with a bandwidth of a few kHz is a good way to get the best performance from the receiver.

The standard filter bandwidth for HF SSB operation is 2.4 to 2.8 kHz. FM and AM operation use 6 to 10 kHz filter bandwidths. Filters with bandwidths of 1.5 to 2.0 kHz are available for operating under crowded conditions with some loss of fidelity. For Morse code and digital modes, the standard filter is 500 Hz wide and is a good option to select. Narrower filters, down to and below 250 Hz, are available.

Another kind of filtering removes noise that is received along with the desired signal. This is called noise reduction and is usually turned on and off with a switch labeled NR. The radio may just have one general purpose NR function or different ones for voice and CW. NR often doesn’t work well with digital modes. You can try each setting and decide which you like best or whether you want to use them at all.

Both analog and digital radios that are used for CW and SSB operation offer noise blankers. The controls for noise blankers are labeled NB. Noise blankers are used to remove short noise bursts called impulse noise. Noise blankers work by detecting the noise pulse and cutting off or “blanking” the receiver’s output during the pulse. Most radios have a general purpose NB feature, and some higher-end models have more than one. Noise blanking is intended primarily for on ignition noise (from gas engines) and power-line noise.

Noise blanking, noise reduction, and preamps can all make a receiver susceptible to overloading by strong signals. When this happens, it can sound like the strong signals themselves are generating the spurious signals and noise. Before assuming that a signal is causing interference, turn off these features to be sure your own receiver isn’t at fault!

VHF/UHF antennas

Most antennas used above 50 MHz at fixed stations are either short whips (thin steel or aluminum rods) or beams. Whips mounted so that they’re vertical are used for local FM operation, whereas beams — antennas that transmit and receive in a preferred direction — are used for VHF/UHF DXing (contacting a distant station) on SSB and CW. The most common type of beam antenna is called a Yagi, after Japanese scientists Yagi and Uda, who invented the antenna in the 1920s. A Yagi has several straight rods or tubes (called elements) mounted on a long supporting tube called a boom. Log-periodics similar to large TV antennas with lots of elements are another type of beam antenna used by hams.

Polarization is the vertical or horizontal orientation with respect to the ground of the antenna and the radio waves from it. If an incoming radio wave and the antenna are oriented differently, called cross-polarization, the antenna won’t receive the radio wave very effectively. Polarization is most important on the VHF and UHF bands, where signals usually arrive with their polarization largely intact. On the HF bands, travel through the ionosphere scrambles the polarization so that it’s much less important.

FM operating is done with vertically polarized antennas because vertical antennas on vehicles are omnidirectional, meaning that they transmit and receive equally well in all directions. These characteristics are important for mobile operation — the first widespread use of FM. To prevent cross-polarization, the base antennas are vertical, too. This convention is universal.

You can mount mobile antennas as removable or permanent fixtures. The most easily removed antennas are the mag-mount models, which use a magnetic base to hold themselves to a metal surface. Mag-mount antennas are available from HF through UHF. Lip-mounts, such as the Diamond K412 (www.diamondantenna.net/k412snmo.html), can be attached to a trunk, hood, or hatchback. The drawback of these mounts is that the installation isn’t as clean as that of a permanently mounted antenna.

Drilling a hole in your car for a permanent mount, such as for an NMO-style base, looks best of all. Trunk-mount antennas for VHF and UHF look good and perform well. Roof-mount antennas perform the best but are most exposed to damage and have the biggest visual impact. All three options are fairly close in performance.

Whichever method you choose, be sure that you can remove the antenna from the mount to deter theft and for clearance, such as in a car wash or parking garage. You can generally route antenna cables under trim, carpet, and seats.

A popular and inexpensive vertical antenna is the simple quarter-wave whip, or ground-plane, antenna. You can build a short ground-plane antenna as a first antenna project (www.arrl.org/files/file/Technology/tis/info/pdf/ab18-16.pdf).

Operators chasing long-distance VHF and UHF contacts use beam antennas that are horizontally polarized. Many of the long-distance VHF and UHF propagation mechanisms respond best to horizontally polarized waves. If you have an all-mode radio and want to use it for both FM and SSB/CW/digital operating, you’ll need both vertically and horizontally polarized antennas.

For operating on CW and SSB where horizontal polarization is used, you can use horizontal loops called halos. These antennas are practical for in-motion use from 50 MHz through the 432 MHz bands. (You can see pictures of these loops in the popular catalogs.)

If you choose to use a beam on VHF and UHF bands, it’s a good idea to use 3 to 5 elements on 6 meters and 5 to 12 elements at higher frequencies. These antennas are small enough to mount and turn with heavy-duty TV antenna rotators.

HF antennas

At HF, antennas can be fairly large. An effective antenna is usually at least ¼ wavelength in some dimension. On 40 meters, for example, a ¼-wavelength vertical antenna is a metal tube or wire 33 feet high. At the higher HF frequencies, antenna sizes drop to 8–16 feet but are still larger than even a big TV antenna. Your physical circumstances (and any regulations or restrictions) have a great effect on what antenna you can put up. Rest assured that a large variety of designs can get you on the air.

Wires, verticals, and beams are the three basic HF antennas used by hams all over the world. You can build all these antennas with common tools or purchase them from the many ham radio equipment vendors.

Wire antennas

The simplest wire antenna is a dipole, which is a piece of wire cut in the middle and attached to a feed line, as shown in Figure 12-3. The dipole gives much better performance than you may expect from such a simple antenna. To construct a dipole, use 10- to 18-gauge copper wire. It can be stranded or solid, bare or insulated.

Although you often see the formula for dipole length given as 468/f, the building process is a lot more reliable if you begin with a bit longer antenna and make one or two tuning adjustments. Start with an antenna length of

Length in feet = 490 / frequency of use in MHz

Allow an extra 6 inches on each end for attaching to the end insulators and tuning and another 12 inches (6 inches × 2) for attaching to the center insulator. If you’re building a 10 meter dipole, you should start with a length of 490 / 28.3 = 17.3′ + 6″ + 6″ + 12″ = 19.3 feet.

To assemble the dipole, follow these steps:

1. Cut the wire exactly in the middle, and attach one piece to each end insulator, just twisting it back on itself for the initial check.
2. Attach the other end to the center insulator in the same way.
3. Attach the feed line at the center insulator, and solder each connection.
4. Attach some ropes, and hoist the antenna in the air.

5. Check the dipole.

   Make some short, low-power transmissions to measure the standing wave ratio (SWR, a measure of RF energy reflected back to the transmitter by the antenna), as explained in your radio’s operating manual, or use an antenna analyzer such as an MFJ-259 (www.mjfenterprises.com). The SWR should be somewhat less than 2:1 on the frequencies you want to use.

6. Adjust the antenna’s length.

   If the SWR is low enough but at too high a frequency or is lowest at the high end of the band, loosen the connections at the end insulators and lengthen the antenna by a few inches on each end.

   If the frequency of lowest SWR is too low, shorten the antenna by the same amount.

   Repeat the process until SWR is satisfactory.

7. Make a secure wrap of the wire at the end insulators, solder the twist if you like, and trim the excess.

   You’ve made a dipole!

You can follow the same steps for most simple wire antennas; adjusting the lengths as necessary.

Figure 12-3 shows some examples of simple wire antennas you can build and install in your backyard or use for portable operation. Most cost only a few dollars and can be built and installed in an afternoon. There’s a special sense of satisfaction in making contacts via antennas that you built yourself.

You can connect the dipole directly to the transmitter with coaxial cable and use the dipole on the band at which it’s ¼ wavelength long or any odd number of ½ wavelengths. A dipole tuned for 7 MHz, for example, works reasonably well on the 21 MHz band, too, where it’s approximately 3½ wavelengths long.

Other common and simple wire antenna designs include

• Inverted-V: This dipole is supported at its midpoint, with the ends angling down at up to 45 degrees. This antenna requires only one tall, central support and gives good results in nearly all directions.
• Full-wavelength loop: Attach a feed line at the middle of the loop’s bottom and erect the loop so that it’s vertical. Then the feed line works best broadside to the plane of the loop. These antennas are larger than dipoles but radiate a little more signal in their favored directions.
• Non-resonant doublet: The wires of this antenna are fed at the center with open-wire or ladder-line feed line and used with an antenna tuner to cover several bands. These antennas usually aren’t ½ wavelength long on any band, so they’re called doublets to distinguish them from the ½-wavelength dipoles.
• Trap dipole: This antenna uses some appropriately placed components to isolate portions of the antenna at different frequencies so that the dipole acts like a simple ½-wavelength dipole on two or more bands (www.arrl.org/hf-trap-antennas).
• Random-length wire: Attach some open-wire feed line 15 to 35 feet from one end, and extend the wire as far and high as you can. A couple of bends won’t hurt. You have to use an antenna tuner at the transmitter. This antenna’s performance is hard to predict, but it’s an excellent backup or temporary antenna that is popular for portable operation.

For more information on these and many other antennas you can build, check out the ARRL’s antennas page at www.arrl.org/antennas.

If you don’t have the perfect backyard to construct the antenna of your dreams, don’t be afraid to experiment. Get an antenna tuner (or use the one in your radio), and put up whatever you can. You can even bend wires or arrange them at strange angles. Antennas want to work!

Beam antennas

The most common HF Yagi today is a three-element design (a reflector, a driven element, and a director). The antenna works on three popular ham bands (20, 15, and 10 meters) and so is called a tri-bander. Figure 12-4 shows a three-element Yagi beam with a lowest operating frequency of 14 MHz. The antenna is on a 55-foot telescoping mast.

Log periodics are also used on the HF bands, with popular models available that cover 20 through 10 meters and all the frequencies in that range. These antennas have a similar appearance to Yagis but have more elements, and all of them are connected to the feed line.

HF beams can be made from square or triangular loops. They work on the same principle as the Yagi, but use loops of wire instead of straight elements made from rod or tubing. Square-loop beams are called quads, and the triangles are called delta loops.

A beam antenna, such as the one shown in Figure 12-4, can be rotated, which allows you to concentrate your signal or reject an interfering signal in a certain direction. You can place small HF beams on inexpensive masts or rooftop tripods, although they are too big for most structures designed for TV antennas. You also need a rotator that mounts on the fixed support and turns the beam. You can control the rotator from inside the station with a meter to indicate direction (see “Supporting Your Antenna,” later in this chapter).

A dipole for 14 MHz or a higher frequency is short enough to be rotated like a beam. This antenna can be surprisingly effective. Rotatable dipoles are available from several manufacturers that work on several of the HF bands.

Most hams start on HF with a wire or vertical antenna. After you operate for a while, the signals you hear on the air give you a good idea of which antennas are effective. Visit other ham stations to get more ideas for antennas suitable for you. After you have some on-the-air experience, you can decide whether you need a beam antenna.

Feed line and connectors

Gee, how tough can picking a feed line be? It’s just wire, right? Not at all, as Figure 12-5 shows. As I mention in Chapter 2, there are two basic types: coaxial cable and open-wire.

Feed lines are transmission lines, just like high-voltage power lines. They’re basically the same thing but for different types of signals.

Coaxial cable or “coax” (pronounced “co-ax”) has a center conductor surrounded by a plastic insulator (also called the dielectric), which, in turn, is surrounded by a metal sleeve called the shield. The shield is covered by a protective plastic jacket. The signal is contained entirely inside the cable, as the figure shows. Coax can be bundled with other cables and laid directly on metal surfaces without affecting the signals inside. Most amateur feed lines are coax.

Open-wire feed line also goes by several other names: parallel-conductor, window line, ladder line, and twin lead. It is just two wires held apart by plastic insulation (window line) or by individual plastic or ceramic spacers (ladder line). The signal flows equally on both wires. Because the wires are not surrounded by any shielding material, open-wire feed line has to be separated from other feed lines and any conductive surfaces.

Each type of feed line has a different characteristic impedance (the symbol is Z₀), which describes how the signal inside divides itself between voltage and current. Most coaxial cable has a characteristic impedance of 50 ohms. Common types of open-wire can be 75-ohm, 300-ohm, 450-ohm, or 600-ohm. This value is important for choosing the right feed line for an antenna. The antenna manufacturer will recommend the right feed line’s characteristic impedance.

You may be surprised that feed line can turn some of your signal into heat, both on transmit and receive. This is called feed line loss. Some types of feed lines are lossier than others.

When I started hamming, I used 100 feet of RG-58 with a 66-foot dipole that I tuned on all bands. I didn’t realize that on the higher bands, I was losing more than half of my transmitter output and received signals in the coax. The 50-foot piece I was using on my 2 meter antenna lost an even higher fraction of the signals.

Although losing 50 percent, or 3 dB (decibels), is only about half an S unit (S units measure signal strength; a change of 1 S unit represents a factor of 4 times higher or lower power), I lost a few contacts when my signals were weak or the band was noisy. Making up that loss with amplifiers costs hundreds of dollars. Changing antennas to a beam with 3 dB of gain costs at least that much, not counting the mast and rotator. That makes the extra cost of lower-loss RG-213 cable look like a pretty good bargain.

Table 12-2 compares several popular feed lines in terms of their relative cost (based on RG-58) and the loss for a 100-foot section at 30 MHz and 150 MHz. The loss is shown in dB and in S units on a typical receiver, assuming that one S unit is equivalent to 6 dB.

The moral of the story is to use the feed line with the lowest loss you can afford. Open-wire feed line is a special case because you must add an impedance transformer or tuner to convert its higher characteristic impedance to the 50 ohms needed by transmitters. This adds some extra expense.

To save money on feed line, buy it in 500-foot spools from a distributor. If you can’t afford to buy the entire spool, share the spool with a friend or two. Splitting the expense is an excellent club buy and can save more than 50 percent compared with buying cable 50 or 100 feet at a time. Do the same for coaxial connectors, buying them in quantity and sharing the cost.

Beware of used cable unless the seller is completely trustworthy. Old cable isn’t always bad but can be lossy if water has gotten in at the end or from cracks or splits in the cable jacket. If the cable is sharply bent for a long period, the center conductor can migrate through the insulation to develop a short or change the cable properties. (Migration is a particular problem with foam-insulation cables.)

Before buying used cable, examine the cable closely. The jacket should be smooth and shiny, with no obvious nicks, dents, scrapes, cracks, or deposits of adhesive or tar (from being on a roof or outside a building). Slit the jacket at each end for a few inches to expose the braid, which should be shiny and show no signs of corrosion or discoloration whatsoever. Slip the braid back. The center insulator should be clean and clear (if solid) or white if foam or Teflon synthetic. If the cable has a connector on the end, checking the cable condition may be difficult. Unless the connector is newly installed, you should replace it anyway, so ask if you can cut the connector off to check the cable. If you can’t cut it off, you probably shouldn’t take a chance on the cable.

The standard RF connectors used by hams are BNC, UHF, and N-type connectors. BNC connectors are used for low power (up to 100 watts) at frequencies through 440 MHz. UHF connectors are used up to 2 meters and can handle full legal power. N connectors are used up through 1200 MHz, can handle full legal power, and are waterproof when properly installed. (Photos or drawings of connectors are shown in vendor catalogs, such as The RF Connection catalog at www.therfc.com.)

Good-quality connectors are available at low prices, so don’t scrimp on these important components. A cheap connector works loose, lets water seep in, physically breaks, or corrodes, eating up your valuable signals. By far the most common connector you’ll work with is the PL-259, the plug that goes on the end of coaxial cables. The Amphenol 83-1SP model is the standard PL-259 connector. By buying in quantity, you can get these high-quality connectors at a steep discount compared with purchasing them individually.

Installing PL-259 connectors is part of ham radio’s technical side and requires a bit of craft and skill. Ask an experienced builder to show you how to do it properly, with all the connections soldered and then waterproofed.

To crimp or not to crimp? You can install a crimp-on connector quickly and get reliable service if you do it right. Crimped connectors also work outside but absolutely require proper waterproofing, which means more than a layer of electrical tape. Crimping tools, or crimpers, are available for less than $50. If you have a lot of connections to make, a crimp-on connector may be a good choice.

Waterproofing connectors requires attention to detail and the proper materials. Water in connectors causes many problems at radio frequencies, so learn how to do it right every time. Waterproofing techniques for the common PL-259 are listed in the ARRL Handbook and the ARRL Antenna Book.

Antennas and trees

Although Marconi used a kite for his early experiments, a handy tree is probably the most common antenna support. A tree often holds up wire antennas, which tend to be horizontal or use horizontal support ropes. The larger rotatable antennas and masts are rarely installed on trees (not even on tall, straight conifers) because of the mechanical complexity, likelihood of damage to the tree, and mechanical interference between the antenna and tree.

Nevertheless, for the right kind of antennas, a tree is sturdy, nice to look at, and free. The goal is to get a pulley and halyard (the lifting rope) into the tree at the maximum height. If you’re a climber (or can find someone to climb for you), you can place the pulley by hand. Otherwise, you have to figure out some way of getting a line through the tree so you can haul up a pulley. You may be able just to throw the antenna support line over a branch. Bear in mind that when a line is pressing against the bark of a tree, the tree can rub and chafe against the line until the line breaks. (This catastrophe always happens at night, in a storm, or right before an important contact.) If the line stays intact, the tree tries to grow around the line, creating a wound that makes raising or lowering the antenna impossible.

Most simple antennas can be supported with ropes over a branch. If you want to avoid damage to the tree, bringing in an arborist or a tree service professional to do the job right, using sturdy, adequately rated materials, may be a good idea. Radio Works has a good introduction to antennas in trees at www.radioworks.com.

Masts and tripods

A wooden or metal mast is an inexpensive way to support an antenna up to 30 feet above ground. If you’re handy with tools, making a homebrew mast is a good project; numerous articles about their construction are in ham magazines. Masts are good candidates to hold up wire HF antennas and VHF/UHF antennas, such as verticals and small beams. If you’re just supporting a VHF or UHF vertical, you won’t need a heavy support and probably can make a self-supporting mast that doesn’t need guy wires. If you area has high winds or if the mast is subjected to a side load (such as for a wire antenna), however, it needs to be guyed.

One commercially available option is a telescoping push-up mast, designed to hold small TV antennas and often installed on rooftops. Push-ups come in sizes up to 40 feet, with guying points attached. You can also construct masts by stacking short sections of metal TV antenna mast, but you have to add your own guying points. You can’t climb either telescoping or sectional masts, so mounting the antenna and then erecting the whole assembly is up to you. You can also mount a section or two of stacking mast on a chimney to support a small vertical. Push-up and TV masts are available (along with all the necessary mounting and guying materials) online — just search for tv antenna push-up mast and you’ll get lots of choices.

One step beyond the mast is the roof-mount tripod. The lighter tripods are used for TV antennas and can hold small amateur antennas. Larger tripods can handle midsize HF beams. Tripods are good solutions in urban areas and in subdivisions that may not allow ground-mounted towers. Tripods ranging from lightweight to heavy-duty are available from several tower and antenna manufacturers.

In recent years, multiple-section telescoping fiberglass masts have become available at low cost, such as those from Spiderbeam (distributed by Vibroplex in the U.S. at www.vibroplex.com). These masts can’t hold a lot of weight but are perfect for small wire antennas and verticals. They make great portable antenna supports, too.

Towers

By far the sturdiest antenna support is the tower. Towers are available as self-supporting (unguyed), multisection crank-up, tilt-over, and guyed structures 30 feet tall and higher. Towers are capable of handling the largest antennas at the highest heights, but they’re substantial construction projects, usually requiring a permit to erect. Table 12-3 lists several manufacturers of towers.

The most common ham tower is a welded lattice tower. This tower is built from 10-foot sections of galvanized steel tubing and welded braces. You must guy or attach it to a supporting structure, such as a house, at heights of 30 feet or more. A modest concrete base of several cubic feet is required to provide a footing. Lattice towers for amateur use are 12 to 24 inches on a side and can be used to construct towers well over 100 feet high. Lattice towers are sufficiently strong to hold several large HF beam antennas, if properly guyed. Tilt-over towers are lattice towers hinged in the middle so that you can pivot the top sections toward the ground by using a winch. Because of mechanical considerations, tilt-overs are limited to less than 100 feet in height.

Crank-up towers are constructed from telescoping tubing or lattice sections. A hand-operated or motorized winch raises and lowers the tower with a cable and pulley arrangement. A fully nested crank-up is usually 20 to 25 feet high, reducing visual effect on the neighborhood, and when fully nested and blocked for safety you can climb it to work on the antennas. Crank-ups also usually have a tilting base that aids in transporting and erecting the tower. Crank-ups don’t use guy wires, so they depend on a large concrete foundation of several cubic yards. This keeps their center of gravity below ground level to prevent tipping over when fully extended. You can install crank-ups in small areas where guying isn’t possible; they’re available in heights of up to 90 feet.

Self-supporting towers are triangular in cross section like lattice towers, and rely on a large concrete base for center-of-gravity control. They’re simpler and less expensive than crank-ups. Available at up to 100 feet, they have carrying capacity similar to that of fixed lattice towers. Mounting antennas along the length of a self-supporting tower is more difficult than for a fixed lattice tower with vertical supporting legs.

Be extremely careful when buying a used tower or mast. Unless the item has been in storage, exposure to the elements can cause corrosion, weakening welds and supporting members. If it’s disassembled improperly, the tower can be damaged in subtle ways that are difficult to detect in separate tower sections. A tower or mast that has fallen is often warped, cracked, or otherwise unsafe. Have an expert accompany you to evaluate the material before you buy.

You can construct self-supporting towers from unorthodox materials such as telephone poles, light standards, well casing, and so on. If a structure of any sort can hold up an antenna, rest assured that a ham has used one to do so at some time. The challenge is to transport and erect the mast, climb it safely, and create a sturdy antenna mounting structure at the top.

In almost any urban or suburban area, you need a building permit to put up a tower. There may also be restrictions included in your property deed or homeowners association (HOA) rules. Your homeowners insurance also has to be updated to include the tower as part of the house or as an auxiliary structure. Check these out first to avoid an expensive mistake.

Regardless of what you decide to use to hold up your antennas, hams have a wealth of experience to share in forums such as the TowerTalk email list. You can sign up for TowerTalk at www.contesting.com. The topics discussed range from mounting verticals on a rooftop to which rope is best to giant HF beams, to how to locate true north. The list’s members include experienced hams who have dealt with some difficult questions.

When you join an online community like TowerTalk, before you start asking questions check the archives of previous messages. Also read any FAQ files or other documents that may be available. The longtime members will appreciate it.

Rotators

A rotator is a motorized gadget that sits on a tower or mast and points antennas in different directions. Rotators are rated in terms of wind load, which is measured in the number square feet of antenna surface it can control in strong winds. If you decide on a rotatable antenna, you need to figure out its wind load to determine the size rotator it requires. Wind load ratings for antennas are available from antenna manufacturers. The most popular rotators are made by Hy-Gain (www.hy-gain.com) and Yaesu (www.yaesu.com).

Although the words “rotor” and “rotator” are used interchangeably, they don’t mean the same thing. The rotator is the device that causes something to rotate, like an antenna mast. The rotor is something that turns. So, the correct term for what points your antenna is “rotator.”

You need to be sure that you can mount the rotator on your tower or mast; some structures may need an adapter. Antennas mount on a pipe mast that then sits in a mast clamp on top of the rotator. If you mount the rotator on a mast, as shown on the left side of Figure 12-6, you must mount the antenna right at the top of the rotator to minimize side loading. This type of installation reduces the maximum allowable antenna wind loading by about half.

Inside a tower, the rotator is attached to a rotator plate (a shelf inside the tower the rotator is attached to), and the mast extends through a sleeve or thrust bearing (a tube or collar that hold the mast centered above the rotator), as shown in the center and on the right side of Figure 12-6. Because using a bearing in this way prevents any side loading of the rotator, you can mount antennas well above the tower top if the mast is sufficiently strong.

An indicator assembly called a control box, which you install in the station, controls the rotator. The connection to the rotator is made with a multiple-conductor cable. Install the feed lines to the antennas in such a way so that they can accommodate the rotation of the antennas and mast.

Used rotators can be risky purchases. They’re always installed in exposed locations and wear out in ways that aren’t visible externally. Even if the rotator turns properly on the bench, it may jam, stall, or slip under a heavy load. Buy a new rotator or get a used one from a trusted source for your first installation. Norm’s Rotor Service (www.rotorservice.com) and C.A.T.S. (www.rotor-doc.com) both sell refurbished rotators.

Radio accessories

You can buy or build hundreds of gadgets to enhance whatever style or specialty you choose. Here’s some information on the most common accessories that you need to get the most out of your station.

PC or Mac or …?

Most ham-station computers are Windows-based machines. The vast majority of software available for ham applications runs on the Windows operating systems.

Linux has an increasing number of adherents, particularly among digital-mode enthusiasts. The Raspberry Pi miniature PCs run various “flavors” of Linux, too. Here are three websites that focus on Linux software:

• Hamsoft: radio.linux.org.au
• AC6V.com: www.ac6v.com/software.htm#LIN
• DXzone: www.dxzone.com/catalog/Software/Linux/

The Macintosh computing community is also well-represented in ham radio software with programs available for all of the common ham radio uses available. The Ham-Mac mailing list (www.mailman.qth.net/mailman/listinfo/ham-mac) is full of information for Mac fans. A useful website devoted to bringing together Macintosh computers and ham radio is machamradio.com.

There are many apps for Android and iPhone tablets and phones. You can shop in the online stores to see what’s available. Functions range from simple calculators to keeping track of who’s on the air to remote control of entire stations. If your phone supports Bluetooth, an audio adapter will allow you to connect a radio’s audio input and output to the phone or tablet.

Regardless of what platform and operating system you prefer, software tools and programs are available to help you enjoy any type of operating you like. Some software is supplied by commercial businesses, and the amateur community has developed an amazing amount of shareware and freeware. Hams freely contribute their expertise in any number of ways, and developing software is a very popular activity.

Digital modes

Operation on most of the digital modes is rapidly converging on the sound card as the standard device to send and receive data. With a simple data and radio control interface, your computer and radio form a powerful data terminal. Chapter 2 shows a typical station configuration for operating this way.

MFJ Enterprises (www.mfjenterprises.com) and West Mountain Radio (www.westmountainradio.com) both manufacture popular data interfaces. The Signalink (www.tigertronics.com) includes high-quality sound card functions in an external interface that communicates with the PC over a USB link.

If you choose to use an external multiple-mode controller for the digital modes, such as the Timewave PK-232 or DSP-599zx (www.timewave.com), Kantronics KAM (www.kantronics.com), or MFJ-1278B, you need only a terminal program such as Hyperterm (Windows), xterm (Linux), or Terminal (Mac).

Radio control

Radios have an RS-232, USB, or Ethernet control interface through which you can monitor and control nearly every radio function. (Icom uses a proprietary interface called CI-V that requires a converter.) Because of that flexibility, some control programs replicate the radio’s front panel on the computer’s screen. Some radio manufacturers have a radio control package that you can purchase or download. Third-party programs such as Ham Radio Deluxe (www.hrdsoftwarellc.com) integrate radio control with logging software.

Hardware considerations

If you don’t do complex antenna modeling or high-performance software defined radio, you don’t need to own the latest and greatest speed-demon computer. If you’re thinking about upgrading a home computer, a computer that’s a couple of years old does just fine in the ham station. Furthermore, the flood of cheap surplus computers available for a song means you can dedicate a computer to its own specific task, such as running your logging software or monitoring an APRS website, and not tie up your main computer.

If you decide to purchase a new computer for the station, be aware that many ham radios and accessories use the RS-232 serial COM port, which has been phased out on PCs in favor of USB. (RS-232 ports are now referred to as legacy ports.) Integrating a USB-only PC into the ham station means that you either have to purchase a serial port expansion card or use USB-to-RS-232 converters. More and more radios and accessories are converting to USB interfaces, however.

Remote control rules

Before you start getting that gleam in your eye, imagining big towers holding antennas high in the air, remember there are a few rules you must follow:

• License authority: You have to be licensed at the location of the transmitted signal. Some U.S. hams have set up stations in other countries or in other areas of the world, such as the Caribbean. This requires either a local license or a reciprocal operating permit. You can find out more about either of those at the ARRL’s web page for International Operating. Some types of operating permission require you to be physically present in the licensing country, so be sure to read the fine print!
• Permission: Trite but true, you have to have permission to use a transmitter. Whether you have a license to operate at the site or not, you still have to have permission to use the equipment.
• Identification: When you send your call sign, be sure it indicates the location from which you are transmitting. If you are a U.S. ham and the station is in the U.S., then no problem — just send your regular call sign. If you are connecting to the station across a national border, you’ll have to use a call sign from the station’s country. And some awards and operating events require hams to use call signs that indicate where they are operating from.
• Control: Regardless of how well you design the station, you have to be able to turn off the transmitter no matter what. Some security controllers accessible by phone can turn a relay on and off to control AC power to the station. You can even buy power strips with a web interface. Having a method that uses a different method of access than the usual control link is a good idea.

Remote operation is a lot of fun and can make ham radio accessible to you wherever you may be. For example, one well-known contest operator frequently fires up his home station in Ohio while sitting in a hotel room in Tokyo, Japan! He loves that he can get on the air in his favorite events even when his business takes him out of the country. But follow the rules and don’t abuse the privilege — it wouldn’t take more than a few bad apples to spoil the remote operating barrel.

Accessing a remote control station

A good overview of the state of remote control at the time this edition was written (early 2018) is available in Remote Operating for Amateur Radio, by Steve Ford (WB8IMY). Even though some of the software options have changed, the basics are sound. The book is available from the ARRL and other ham radio booksellers. The ARRL Handbook’s 2018 edition added an updated section on remote stations, including site evaluation and alternative power.

The most common setup is to use the Internet with a PC at each location running a station control program. The remote station is typically configured something like Figure 12-7. (The additional DTMF controller connected to the phone line is needed in case the computer loses control of the radio and you need to shut everything down and start over.)

If you set up your station at home but operate it away from home, the controlling software can run on a laptop so you can fire up the rig from a hotel room or coffee shop. There’s no reason why you have to lug around a laptop, either. A smartphone or tablet computer can be quite enough. The remote-control software developed by Pignology (www.pignology.net) runs on an iPhone and even includes logging software so that everything fits in the palm of your hand.

If you think you might like to try remote operating, start by checking out one of the many online remote receivers at WebSDR (www.websdr.org). There are dozens of receivers available for you to use located all over the world. Try listening to the same station from different receivers to get an idea of how propagation varies!

Why go to the trouble of building the station yourself? “Time-share” remote stations are maintained by Remote Ham Radio (www.remotehamradio.com). The stations are available for a per-minute fee (with a paid membership). Be careful though, because using these capable stations will spoil you!

Remote operating is becoming very popular. More radios support it, more software is available, and high-speed Internet is available in more places than ever. The technology to make it work is available, radios themselves are easier to control over the Internet, and commercial products are appearing that provide plug-and-play operation. You’ll have the option of building a traditional home station and be able to operate it from wherever you are. Some clubs and informal groups build and share a remote station. As I say at the beginning of the chapter, this is an exciting time!