Strangely Behaving Signals

While the causes for QRM were well understood, mostly man-made, and could be dealt with through cooperation and tuning techniques, other disruptive on-air phenomena were clearly beyond such controls: those caused by nature. Some, such as static (QRN, also called strays), although understood to a large degree, had no known effective remedy.  Others, such as fading, were not understood at all. At constant transmitter power, what natural phenomena could possibly cause a signal to fluctuate in strength? Why wasn’t a … Continue reading

Regulations and Enforcement, Hard and Soft

Descriptions of the radio laws and anecdotes about their enforcement during the early years paints a picture of a regulatory environment that could be alternately strict or flexible.  A QST article in 1916 by “Little Willie” described his and his friends’ experience preparing for and taking an exam for the “first grade comm” (First Grade Commercial license) which consisted of a code test and a written test.1  Although the author’s identity is likely fictitious, the story probably relates an actual … Continue reading

Cooperation and QRM

In mid-February 1916, coincident with Maxim’s second article on relaying, one of the first organized relay tests was run. With everyone sharing very little spectrum, cooperation was the only way to avoid QRM (a constant fact of life at the time) and hear weak, distant signals. In a rare cooperative operation between an amateur group and the government, a relay test was conducted on Washington’s Birthday by Colonel W. P. Nicholson, 9XE at the Rock Island Arsenal in Illinois, and … Continue reading

Trunk Lines

Clearly, Maxim’s main goal was to establish reliable relaying across the entire country. He was excited by its collaborative nature. In the third and last free issue of QST he wrote, “The co-operation of a few unknown but nevertheless kindred spirits between Portland, Maine and Portland, Oregon, by means of which the message is handed on, adds a touch to the whole scheme and makes it almost Utopian.”1 It was the primary reason for organizing the League, whose membership had … Continue reading

The Relay’s the Thing

Whether for public service or as a challenge worth attacking, transmitting information across ever greater distances is what drove members of the Relay League to organize. The thrill of wireless communication was reinforced with each additional mile covered, even as signals became weaker. Relaying was an obvious way to extend range beyond the capability of one pair of stations in direct contact, and it required more than just knowing who was located where. Urged by the first district Radio Inspector, … Continue reading

The Audion

Vacuum tubes revolutionized radio, changing it more than any other single invention. When first introduced, however, even the scientists and engineers working with them did not fully understand how they worked. One of the first tubes to appear in QST was the Audion, by DeForest. Although it had been introduced back in 1905, it was expensive and amateurs did not begin to use it until seven years later, when 22-year-old Edwin Armstrong demonstrated its practical use as a regenerative detector. … Continue reading

Aerials, Attachments, and Audibility

Aside from the spark gap, the aerial was then, as the antenna system is today, a source of intense interest and experimentation. Aerials partly governed resonance in both transmitter and receiver, and therefore played an integral part in determining the wavelength of operation. In QST, The Old Man advised that amateurs should not simply make aerials as long as possible but stick with lengths of around 175 meters with short lead-in and ground connections, so as to stay close to … Continue reading

Spark Radio

Before tubes became available and affordable and made electronic oscillators practical, the spark gap circuit was the most widely used method for generating radio frequency (RF) signals. Its basic design and operation are simple. A capacitor is connected in series with an inductor and a pair of electrodes separated by a small distance—a spark gap. The capacitor, commonly called a condenser at the time, is charged by a high voltage supply. When this voltage reaches a critical level, a spark … Continue reading