On March 2nd, 2012, an EF4 tornado struck the town of Henryville in southern Indiana, virtually wiping it off the map. A second, less severe EF1 tornado followed the same path about an hour later, compounding the destruction. The storm damaged the infrastructure in the region, causing a complete disconnection from the outside world.
Utility lines and cell phone towers disappeared, while telephone land lines were down across most of the area. The 800 MHz public service radio system used by emergency services was inaccessible in most of the area and severely overloaded where it did work.
Soon after the storms passed, local amateur radio operators, known as “hams,” arrived with their mobile and portable radio stations and quickly sprang into action to reestablish communications. They went on foot to areas inaccessible by vehicle and used handheld radios to help search for victims, provide damage reports, and relay information to emergency management officials.
For several days following the storm, hams continued to pass messages and provide effective communications until the infrastructure could be restored. The impact of these volunteer radio operators and their equipment, which they purchased and maintained, cannot be measured in the number of lives they positively affected.
Occurrences like this happen multiple times each year, and each time, ham radio operators volunteer to establish communications with the outside world. The Henryville tornadoes serve as a reminder of the importance of rapidly and efficiently establishing communication during and after disasters.
HAM Licensing procedures
In the United States, ham radio operators are licensed by the Federal Communications Commission (FCC) after passing a written exam. The different classes of licenses available are technician, general, and extra, with each granting more operating privileges than the previous one. Higher classes require increased technical knowledge, and a good grasp of electronics is helpful.
Knowledge of Morse code is no longer a requirement for any license class, but basic math skills are necessary. License study manuals and smartphone apps are available for prospective hams to prepare for the written exam, and volunteer examiners administer the actual exams.
Upon passing the exam, documentation is sent to the FCC, which then issues the license grant and call sign to the operator. The new ham is allowed to transmit on all permitted frequencies according to their license class.
License upgrades follow the same process and take effect immediately upon passing the exam. More information on exam locations, schedules, and study manuals can be found on the American Radio Relay League’s website: www.arrl.org.
The technician license grants the least operating privileges, while the general and extra license holders have access to additional amateur frequencies, with some portions reserved only for the higher extra class. These two higher-level classes allow for true global communications.
Modern HAM equipment
Obtaining a license is necessary to legally transmit on any of the amateur radio frequencies during non-emergency situations, however, no license is needed to buy amateur radio equipment or listen to communications between hams. In case of an actual emergency, calling for help or responding to a distress call is permissible even without a license.
In the early days of amateur radio, hams used to create their own equipment by piecing together parts from other radios or appliances, or they relied on military surplus equipment. Nowadays, there are commercially manufactured transceivers, antennas, and other gear that can provide reliable and effective communications to hams.
Modern amateur radio stations typically consist of two or three radios that can cover many different frequency bands. Personal computers can be linked to the radios to enable capabilities beyond voice communication, including sending files, images, and even television through ham radio.
One significant advantage of amateur radio is the lack of dependence on grid power. This independence allows hams to operate in any location where an antenna can be installed, such as a deserted island, mountain top, or a ship on the ocean.
Most modern ham radio equipment is designed to operate on 12-volt DC power sources, making it possible to power the equipment using a simple automotive battery. Hams also commonly use solar panels to keep batteries charged. Wind and even small-scale hydroelectric generators can also be utilized to provide power for amateur radio stations.
To understand why amateur radio is more effective than other radio services, it’s necessary to have a basic understanding of how radio waves at different frequencies behave in the radio spectrum. The spectrum is divided into several regions, four of which are important to amateur radio: mid frequency (MF), high frequency (HF), very high frequency (VHF), and ultra-high frequency (UHF). Each radio service is allocated specific frequency ranges within these regions, referred to as “bands,” to prevent interference with other services.
Amateur radio bands are named based on the approximate radio wavelength of the lowest frequency in the band. For example, the “40-meter” band has a wavelength of approximately 40 meters. All ham bands follow this naming convention. In the United States, mid frequencies include the AM broadcast and 160-meter amateur radio bands, which can propagate over long distances but are susceptible to atmospheric noise interference.
The high frequency region, which includes more than half a dozen amateur radio bands, is the most important for amateur radio communication. Two-way communication over vast distances is possible at low power levels in this region, but it’s dependent on the upper atmosphere to bounce signals back down to the surface. The bands that work best at a given time or direction are determined by constantly changing conditions in the ionosphere.
The upper HF region contains citizens band radio frequencies, which can occasionally produce long-range contacts due to “skips.” However, these “skips” are too infrequent for reliable long-distance communication. General and extra class license holders are authorized to operate on allocated bands spread throughout the HF region, ensuring dependable communication.
When conditions change, causing one band to fade, a different band can be used. VHF radio communication is typically “line-of-sight,” which means the antennas must have a direct line of sight with each other. Depending on terrain and other factors, typical VHF mobile contacts can range from 10 to 50 miles.
To overcome the inherent range limitations, amateur radio “repeaters” have been installed throughout the country. These repeaters are owned and operated by individual hams or ham clubs and can cover vast areas. Although these repeaters are normally powered by the utility grid, many have battery or generator backup power to keep them running during power outages. However, they cannot be relied on for continued operation during disasters or extended power failures.
The 2-meter band is widely popular in the VHF region because of its affordability and ease of installation on various vehicles, including bicycles. More repeaters are dedicated to 2 meters than any other band, and some sites may provide services to multiple amateur bands. Although the 6-meter band is located in the lower VHF region and can sometimes achieve long-distance communication, its reliability for long-range communication is inconsistent, much like CB.
VHF has several other two-way radio services, such as marine VHF, multi-use radio service (MURS), and land-mobile radio for businesses. Local emergency and public services like police, fire, medical, and utilities use VHF frequencies primarily in rural areas, whereas urban areas tend to have moved towards higher-frequency systems.
UHF is also a line-of-sight region but performs better at penetrating structures, making it an excellent choice for urban communication. However, it is more susceptible to heavy terrain and obstacles, particularly for longer distances. Many hams prefer the amateur 70-centimeter band in the UHF range, with several repeaters available to expand the range.
The general mobile radio service (GMRS) and family radio service (FRS) also operate in the UHF range but with low power and regulatory restrictions, rendering them no more useful than two cans and a string. Therefore, do not fall for the “22-mile range” claim on the packaging.
Frequency and antennas
As mentioned earlier, frequencies possess different qualities. Lower frequencies are typically more suitable for long-distance communication, while higher frequencies are generally limited to line-of-sight transmissions. Interestingly, VHF and UHF frequencies are utilized in amateur radio for communicating with satellites in low-earth orbit, as well as for moon-bounce or EME (earth-moon-earth) contacts.
For EME contacts, a signal is transmitted from an earth station, reflected off the moon’s surface, and then received by another earth station. Although it can be thrilling, EME requires advanced coordination between the distant stations and specialized equipment, and therefore is not typically used for reliable long-range communication (although it may have strategic uses).
Frequency also affects antenna size. Lower frequencies necessitate a larger or longer antenna, while higher frequencies permit the use of smaller or shorter antennas. This is one of the reasons why VHF and UHF radios are ideal for portable or mobile operations.
To put it simply, a handheld transceiver (HT) is a portable radio that operates on VHF/UHF frequencies and sometimes includes HF bands. HTs are highly convenient for local communication and can access repeaters to provide the same coverage as higher-powered units. They can be carried on a belt or in a pocket and even used in vehicles with the help of an external antenna.
Therefore, it’s a must-have for all hams. When it comes to mobile use, VHF/UHF radios are the popular choice among hams. Some mobile radios also provide HF band capabilities. Mobile radios typically offer a maximum output power of 50 to 75 watts and are usually sturdy. They can be used as base stations or carried in backpacks or ammunition cans with an external battery and antenna.
Full-featured HF radios are usually larger than mobile radios and offer much greater capabilities, along with higher power output in the range of 100 to 200 watts. Any antenna designed for the band or bands it is used for can be connected. These radios can be used as base, mobile, or even portable radios.
Is HAM Radio worth it?
If you’re wondering whether ham radio is worth pursuing, consider this: ham radio is a multifaceted hobby that can provide a range of benefits. While it may require study and practice to fully understand and operate, the capabilities, reliability, and effectiveness of ham radio make it a valuable skill to have.
Ham radio provides a means of communication that is independent of commercial infrastructure, making it an essential tool in emergency situations when traditional communication channels may be down. It also allows for communication over long distances, making it an ideal way to keep in touch with friends and family across the country or even around the world.
Moreover, ham radio is a great way to meet like-minded individuals and connect with a global community of radio enthusiasts. There are various events, contests, and clubs that bring ham radio operators together, providing opportunities to learn, share knowledge, and make new friends.
In short, while getting licensed in ham radio may take some effort, the benefits are well worth it. From emergency communication to international friendships, ham radio offers a unique and rewarding experience that can enhance your life in many ways.