When people think of ham radio, they usually think of high-frequency (HF) home radio stations. These are the stations that send messages directly to another radio station somewhere else in the world. We’ve talked about a lot of other types of amateur radio stations on MAKE: handheld radio VHF stations that communicate through repeaters and satellites, portable HF stations for hiking, mobile HF stations on bicycles. But this month, we’re back to basics to show how to set up a traditional HF amateur radio station at home. (Remember, to operate this type of radio, you will need a ham radio license.)
Choosing the right equipment is an important part of setting up your radio shack. Here’s a look at the equipment you will need and recommendations of products that I think work best for a beginner home station.
[A] HF radio The radio is the core of your station. You will need a transceiver, a radio that can both send (transmit) and receive on the amateur radio bands. A 100 Watt, multi-mode, multi-band radio is a good choice for most operators. Multi-mode means that the radio can be used for different modes such as phone (voice), digital, and CW (Morse code) communications. Multi-band means that the radio works on a wide range of frequencies.
There are many good rigs (radios) out there from which to choose. Two starter rigs that I personally like are the Icom IC-718 and the Yaesu FT-450. The Icom IC-718 gives you the right minimal feature set for around $600 new, $300-$500 used. The only critical feature missing is a narrow filter, which you will need if you do a lot of CW operation. You can pick up an aftermarket 500Hz filter for $115 from w4rt.com. The Yaesu FT-450 is a newer design with more features, including a sophisticated adjustable filter, as well as coverage of a couple of extra bands. The street price is around $750. Among new radios, this is an excellent value, but since it’s a new design, few used ones are available.
[B] Power supply Almost all ham transceivers operate from 13.8V DC power. Wall sockets have 120V AC power which means that your station needs a power supply (just like your laptop). Most 100W rigs consume around 23 Amps at maximum output, so a 25 Amp supply will do. I recommend getting a switch-mode supply rather than a linear, since they’re more efficient. The Astron SS-25 is a good choice at $125. For a little extra money you can get the SS-25M which has voltage and current meters on the front panel.
[C] Accessories Most radios come with a handheld microphone for voice communication, but no CW key for sending Morse code. If you want to do CW, invest in a decent iambic key, like the Bencher BY-1. It costs about $125 new, $50 used. For PSK31, RTTY, and other digital modes, you will need a TNC to interface the radio with your computer (similar to a modem). I recommend the RigBlaster Plug & Play, for around $120.
Antenna The most difficult part of assembling a ham radio station is usually putting up the antenna. Even choosing from among the hundreds of possible designs is hard. As with radios, there are many good options. However, unlike radios, the best antenna for your situation will be largely dependent on the physical constraints of your home. That being said, the design I recommend for most people is a non-resonant wire dipole, fed with ladder line, and matched with an antenna tuner. This configuration is cheap, flexible, forgiving, and it can be very efficient. The antenna equipment and materials suggested below are to build this antenna design. If you are unable to build this design at your home there are many other options you can use.
[D] Dipole antenna A dipole antenna is made out of a long piece of wire. Wireman 501, or any garden-variety 18 AWG (or larger) stranded insulated wire will work fine. See Step 3 for length.
[E] Balun A 100W 4:1 balun like the LDG RBA-4:1 will do.
[F] Heat shrink tubing
[G]“Dog bone” Insulators (2 or 3) Dog bone insulators are a non-conductive way to connect two conductive things.
[I] Coaxial cable (coax) Either RG-58 or RG-8X. See steps 8 and 9 for length.
[J] Ladder line a.k.a. window line 450 ohm window line, e.g. wireman 552. See Step 7 for length.
Embossing heat tool (for heat shrink)
Tool/materials to anchor your antenna to your supports. These will vary based on what you choose to use as supports. See step 6.
The dipole antenna is installed suspended by two supports in an open area. The dipole antenna connects to your radio by way of an antenna tuner (aka transmatch) and balun (a “bal”anced to “un”balanced transformer). Coax and window line are used as feed line to connect everything together.
Step 1: Understanding a dipole antenna A dipole antenna is essentially a long piece of wire, split in half (creating two “poles”), and fed with a radio signal at the split point. Dipoles have a natural resonant frequency, which is related to their length, however when used with a tuner, the exact length of the antenna is not that important. Something on the order of 65 feet is ideal for ham use, although anywhere between 30 and 130 feet should be fine, so you can choose a length in this range that fits in your available space.
Step 2: Finding supports for the dipole antenna There are many different options for where to install your antenna. You can hang it from a tree, between two buildings, suspended above your roof on poles. Outdoors and in the open is better, but in an attic will do.
Ideally, the dipole would be installed horizontally, outdoors, about 65 feet above the ground. But as with length, you can adjust these parameters to fit the constraints of your home and still have a very effective antenna. Try to get the feed point (center) of the antenna as high up as possible, at least 20 or 30 feet above the ground, and away from metal objects. The ends can be inclined up or down from the center, in a “V”, “inverted V”, or “sloper” configuration, and the wire can bend around corners, or hang down in an “inverted U” shape as needed. Trees or buildings can be used as supports, but remember that trees sway in the wind, so you will need to leave enough slack to accommodate the motion, perhaps with a pulley and a weight at one mounting point to keep tension on the line.
WARNING: Do not place the antenna near or above power lines. At some point, your antenna will probably break and fall down, and if it happens to touch a power line, it can electrocute you or anyone else who comes in contact with it or your radio equipment, so don’t take any chances! It should also be kept away from people, especially unwitting passers-by, and animals. Touching the line while someone is transmitting can be dangerous, and the FCC has rules limiting RF exposure for people.
Step 3: Cutting the dipole antenna wire to length Measure the distance between the supports. Subtract a few feet and cut the dipole antenna wire to that length.
Step 4: Connecting the dipole to the window line Cut the dipole antenna wire in half at the center and solder the ends to the window line. After stripping the ends of the wire and window line, twist them together before soldering. Protect the connection with heat shrink tubing.
Some setups use an insulator at the feed point of the dipole antenna for extra strength.
Step 5: Connect the dipole to dog bone insulators Strip away an inch of insulation from each end of the dipole antenna. Cut a 2″ piece of insulation* and slide it 1/2″ toward the end of the wire. Slide a 2″ piece of heat shrink onto the wire. Loop each end of the dipole antenna through a non-conductive “dog bone” insulator then fold the wire back twisting it onto itself. Secure the wire loop by soldering the twisted end. Protect the soldered wire with heat shrink.
*Note the length of your extra piece of insulation may vary depending on the size of your insulator.
Step 6: Suspend the dipole from the supports Install anchors in the brick at each end. Using a short loop of nylon rope, galvanized steel wire, or antenna wire, connect the other eye of the insulator to the anchors.
Step 7: Connecting the balun Cut the window line so that you have enough length to reach the window or exterior wall of your shack, making sure that the window line stays several inches away from any metal objects. Strip the ends and connect them to the balun. Connect a piece of coax to the balun and run it into your shack.
Note: You are using window line and coax as feed line. Window line is more efficient than coax, but unlike coax, it needs to be kept several inches away from metal objects, which makes it difficult to use indoors. So your best bet it to use just enough coax to get out the window, and then ladder line the rest of the way to the antenna. Most baluns are waterproof so yours should be happy living outside.
Step 8: Connecting the tuner The antenna tuner converts the non-resonant dipole into a system that is resonant at the frequency of your choosing. Connect the coax from the balun to the antenna side of the tuner. Connect a piece of coax to the radio side of the tuner.
Step 9: Connecting the radio Connect the radio the tuner’s coax.
Once you have your station up and running, you may find that your tuner won’t match your antenna on certain bands. This can usually be fixed by adding or removing five or ten feet of ladder line. The only time this may not work is if you are trying to tune a short (e.g. 30 foot) antenna on a low (e.g. 80m or 160m) band.
WARNING: Antennas can attract lightning and static electricity, which can damage your equipment and pose a safety hazard. You can add a surge protector or lightning arrestor to the feed line that will provide some degree of protection. These require you to run a conductor to a ground spike. Another way to protect your equipment from this kind of damage is to disconnect the coax from the tuner when you’re not using it (and, obviously, don’t use the radio during thunderstorms). I recommend doing this even if you have a surge protector.
References: http://www.sgcworld.com/Publications/Downloads/ClassicMultiband.pdf http://www.arrl.org/files/file/Technology/tis/info/pdf/0683033.pdf http://www.w6ier.org/images/The%20Lure%20of%20Ladder%20Line.pdf