Popular Science Monthly, August, 1922, pages 74-76:

On  the  Crest  of  the  Radio  Wave!

By  Jack  Binns
America's First Wireless Hero and Most Famous Writer on Radio

Can  Wired  Wireless  Change  Radio  Broadcasting?
MAJOR-GENERAL GEORGE O. SQUIER, chief signal officer of the United States Army, apparently threw a monkey-wrench into the general machinery of radio broadcasting, a short time ago, when he gave a demonstration in Washington of his "wired wireless" system, as applied to music transmission. His success immediately threw the electric light people into paroxysms of joy, and correspondingly caused the new radio fans a lot of perplexity and wonderment.

The  Romance  Would  Be  Lost

    The feeling of the electric light people was well illustrated by the tenor of the articles in their trade publications. They did not hesitate to declare that the system would put the entire broadcasting situation into their hands, and solve the problem of paying for broadcasting by permitting them to establish a toll system. Will it?
    That is the question that has perplexed the radio fan, especially the one who has invested in an elaborate receiving set. I have discussed it pretty generally with some of the most famous men identified with the development of radio. They all seem to agree with me in the belief that the romance of feeling about through the ether, picking up Pittsburgh, or Chicago, or some other station, as your fancy and skill dictate, is one of the prime attractions of the present broadcasting system. Wired wireless broadcasting would kill this chief pleasure of radio.
    I have yet to meet a radio fan who is content to sit back and just enjoy the music scheduled by one particular broadcasting station. He wants to monkey around with the controls, and get a sample of everything that is going in the ether that night. He wants to try for the far-distant stations. When he gets one, he is tickled pink. Wired wireless, because it would restrict us to the program from some one local station--an electric light generating station at that!--would take half the joy out of our evenings of radio adventure.
    And that's not all. How are you going to apply wired wireless to the rural communities? Half the people in this country live in rural districts.
    Radio's great destiny is to bring news, music, lectures, and every variety of entertainment and instruction to these rural communities, breaking down one of the last barriers that have kept the advantages of city life away from the country dweller. Wireless broadcasting will do this cheaply, and in fascinating fashion. "Wired broadcasting" could only do it at great expense.

How  Wired  Radio  Works

BUT what is this "wired wireless" system, anyway? How does it work? The answer is simple enough in its way, even if the invention is so marvelous as to deserve all the recent talk it has created.
    The system was developed by General Squier, chiefly to meet certain conditions that developed during the war. It gets its name because of the fact that instruments usually connected solely with wireless work are applied to wire circuits running between two points. By its use it is possible to simultaneously send upward of 40 different telegraph messages on one wire between two cities. No one of these messages interferes with the others. Nor is this all. In addition, several ordinary two-way telephone conversations can also be carried on at the same time on the same wire without interference, while those 40 telegraph messages are being sent! Think of its commercial possibilities!

Vacuum  Tubes  Act  as  Filters

    For an explanation, we must turn again to the remarkable vacuum tube so familiar to all radio fans. As is well known now, the vacuum tube can be turned into an electrical oscillator, if it is connected with a circuit composed of an inductance and capacity. Such a circuit will generate electric waves of tremendously high frequency.
    Now, all that will be necessary is to have a sufficient number of vacuum tubes, all generating waves of different frequencies, and then to superimpose these frequencies upon the single wire running between the two cities that we wish to put into multiplex communication. The high frequency currents are guided along the surface of this wire without interfering with each other, in just the same manner as waves of different sizes on the ocean will travel over each other and yet maintain their individuality.
    At the receiving end there are other vacuum tubes, connected with circuits of different values in such manner that each will respond to certain frequencies and no others. In other words, each tube acts as a filter, straining out the different frequencies, and permitting only the one fitting itself to pass through to the recording device. An elaborately complex wave, guided along the wire, is thus resolved into its component waves by vacuum tubes at the receiving end, each message, when separated from the combined jumble, being separately recorded.
    In this connection, a very interesting possibility cropped up the other day. I was at a dinner with Philip Berolzheimer, City Chamberlain of New York. During the evening, he asked me if it would be possible to broadcast orchestral or band music, and reproduce it in all of the city's 40 parks, so that in each park, in the open air, 10,000 people could hear it clearly and distinctly.
    I promptly discussed the project with E. B. Craft, Chief Engineer of the Western Electric Company. Without any hesitation, he declared the scheme would be possible, but suggested that the broadcasting be done over a telephone wire instead of by radio.

One  Orchestra  for  Many  Audiences

    If the system proves practicable, it means that a city might support one really high class orchestra, and simultaneously deliver its music to any number of audiences in the open air. As a result of these discussions, it is probable that in the very near future New York City will put such a system through a series of tests. Wired municipal broadcasting of this kind, aided by voice amplifiers in the parks and public halls, would furnish music, entertainment, political debates, election returns, and interesting civic information to the entire population of the city.