Billings (Montana) Gazette, September 12, 1920, page 5:
DeForest radiophone
      This  picture  shows  Dr.  De  Forest's  new  small  "buzzer"  radiophone,  which  has  a  wireless  talking  radius  of  15  miles.  Other  equipment  necessary  to  operate  the  instrument  are  connecting  antennae,  which  can  be  strung  on  a  tree  or  housetop,  and  a  six-volt  storage  battery.  The  three  bulbs,  or  audions,  are  the  "heart"  of  the  radiophone.

International  News  Service  Staff  Correspondent.

    NEW YORK, Sept. 11--Dr. Lee De Forest, whose inventions have made wireless telephony practicable, has just completed his first, easily portable, non-high potential radiophone.
    The apparatus, designed for the camper, farmer, automobilist, yachtsman, forestryman or patroller, can easily be packed in a handbag, and the total weight, including six-volt storage batteries necessary to operate the radiophone, is but 60 pounds.
    "Do you think it will be possible to develop this thing so one can carry a wireless telephone around in his pocket?" the inventor was asked.
    "Ask the battery people," said Dr. De Forest. "Most of the weight is in the battery. So far as receiving messages are concerned, a very light radiophone could be developed, I think, but to transmit messages, electric current is essential, and for that a storage battery would be necessary. No, we are hardly likely to see people going about with radiophones hooked on them."
    The "heart" of the radiophone, Dr. De Forest explained, is a small bulb known as the audion, not unlike an electric light bulb, which contains a filament, grid and plate, which amplifies and transmits electric vibrations.
    "I have worked out the same idea in the larger oscillion tube, which can be used to transmit the spoken word across the Atlantic ocean, if desired," he said.
    "But the radiophone will transmit loud, clear speech, maintaining all of the voice characteristics better than any telephone, and will transmit simultaneously to as many points as desired and all with the same efficiency to all of them. Rain, sun, and fog do not bother the radiophone. Neither do mountains, streams or forests."
    "How far will the portable radiophone transmit messages?"
    "In all weathers, this small instrument will carry very clearly up to 15 miles," Dr. De Forest replied.
    "Why did you invent it?"
    "Because there is a use and demand for it," he said. "The original model I might say, was bought right out of the laboratory by a man who said he couldn't wait for the standardized model which we are preparing to turn out in quantities. Wherever there is water to be crossed or where there are no existing land-wires, the radiophone is much cheaper to install and operate than the telephone."
    "How much will the small set cost?"
    "About $200," Dr. De Forest replied. "But of course, two of them would be necessary for any practical purpose--one on each side of the river or lake or wherever it was decided to use the wireless system."
    "Do you expect the wireless telephone to supplant phones in homes and in the business world today?" he was asked.
    "No. The radiophone will not supplant existing satisfactory wire-line telephone service," Dr. De Forest said. "Radiophone conversation is not secret, unless in code. The radiophone will not supply quite as satisfactory service 365 days out of the year as the telephone because at infrequent intervals static will hinder its operation.
    "Then why don't we begin talking by wireless to Europe?"
    "It can be done any day by any one who desires to spend the money for proper equipment," said Dr. De Forest. "Given good weather, a 20-kilowatt outfit will make speech possible and practical across the Atlantic ocean; a 60-kilowatt apparatus will do it in average weather; a 1,000-kilowatt outfit will do it in bad weather, when static conditions are wrong."
    Long-distance talking is possible by wireless only by use of the audion and oscillion, both invented by Dr. De Forest. These devices are 10,000 times more sensitive than any known detector of electric vibrations.
    "When a business man wants to talk to Londonwall 500, London, he doesn't wish to be told static conditions, either here or abroad, may delay the call half a day," continued Dr. De Forest. "That is one of the chief obstacles to radiophone service to Europe."
    Dr. De Forest said he had just shipped a large number of radiophones, each with 300 miles working radius, to China, on order of the Chinese government.
    "The distance one desires to talk is determined by the number of oscillions and audions employed and the electric energy supplied," said Dr. De Forest "One of our small outfits was heard 1,500 miles in this country."
    Dr. De Forest said there were possibilities, entirely practical, of developing concert entertainment through the radiophone.
    "For $12 I can produce 'listening-in' sets which will enable the user to hear distinctly as if he were in the room where the sound is being produced. The listener may be in the country ten or fifty miles away and thus have an evening's entertainment. It will open up possibilities for rural entertainment add the farmers will be able to 'attend' with their ears, any concert or theatrical performance in a city miles away, though he would not leave his living room.
    "If desired, larger 'listening-in' sets may be had so no headpiece will be necessary for the auditors, the sound being reproduced through a horn, as in a phonograph, and anyone in the farmer's living room would hear the music or entertainment or news that might be transmitted from the city
    "With the audion or oscillion, it is not necessary for the speaker or musician to transmit sounds directly into any receiving device. The sounds are picked up naturally and reproduced precisely.
    "You may remember that Mme. Melba, a few weeks ago, sang for the Marconi people at Chelmsford, England, and her song was heard in Sweden, Italy and Spain. Mme. Melba sang directly into a horn. That is not necessary with the oscillion; it hears like a person and then transmits what it hears.
    "This thing is beyond the experimental stage. At the California Theatre, San Francisco, where an audion is fitted on the stage, the entertainment has been heard, just as I have described, miles away in the country."