What was Part 15 AM like 87 years ago? Based on the magazines and newspapers of the time it was excessively popular, but also problematic in a few ways as this Consumers' Research magazine illustrated...
Part 15 was less than a year old when these 1939-1940 Consumers' Research (CR) articles were published. CR appears to have been exactly what the Consumer Reports magazines are today. Unlike other magazine articles of the time, CR illustrates that not everyone was enthused about these new hobby AM broadcasting gadgets.
The first excerpt from 1939 is a rating of a wireless part 15 AM transmitter, followed by excerpts from a 1940 commentary about shoddy manufacturing practices in general, and lastly the "New Uses for the Wireless Record Player" article, which amongst other things talks about the FBI scrutiny concerning their operation. ...
Consumers' Research BULLETIN
Issued by Consumers' Research, Inc., Washington, N.J.
https://archive.org/details/sim_consumers-research-magazine_1939-1940_9_index
[[[[[[[[[[September, 1939 Issue]]]]]]]]]]]]
Page 42:
C. Not Recommended
Phonograph oscillators such as the RCA, Model RK-24, sold to facilitate the interaction of record players with radios without need for changing connections of the radio. These devices do not give satisfactory high fidelity service. The only suitable method for making a conversion necessary for record playing is to have a radio technician connect the pickup of a good record player with wires, direct to the input side of the audio system of the radio.
RECORD PLAYER ATTACHMENTS
C. Not Recommended
"Wireless" record players, requiring no wire connection to the radio set.
[[[[[[[[[[December 1940 ]]]]]]]]]]
Vol.7 No.4
Page 1:
Off the Editor's Chest
[Excerpts]
.... ... A set manufacturer, in correspondence about the article, referred to the industry's being at "an all-time low in quality." Engineers have been working hard, to devise new circuits which use fewer or cheaper parts, though the cost of production of mass-produced sets is already so low that most of such changes have the effect of permitting the manufacturer of shoddy equipment to make his bad sets still worse either cheaper, or more profitable.
When Consumers' Research reports, as it does at times, that this year's appliance or device is worse than last year's model, there will be some readers perhaps who will ascribe our finding to prejudice or an unwillingness to believe in some principle of automatic progress in industrial production.
The truth is that in a considerable number of industries there is often an actual backward movement in quality -- sometimes in a particular year, sometimes continuing over several years.
In radio it has been established by tests that worse sets are made in mass production today than were made 8 or 9 years ago --yet the possibility of making fine radio sets at economical prices has advanced enormously in the last three or four years, due to important inventions and finer precision and measurement techniques in the making of components, particularly vacuum tubes.
One of CR's own radio consultants has judged from his tests of radios that approximately 60 percent of mass-produced sets reaching the public are in bad working order and have definite faults of some sort (often in some respect the buyer will not be sure of, if aware of their presence at all). ... ...
(((((((((((Dec 1940. (Same Issue))))))))
Page 25:
New Uses for the Wireless Record Player
THOSE of our subscribers who like to play phonograph records at home will probably be interested in an item which appeared in a radio journal recently regarding phonograph oscillators, more popularly known as ‘‘mystery,” or ‘‘wireless,” record players.
These instruments enable the user to reproduce phonograph records through the ordinary radio set without the need for making wire connections between the record player and the radio receiver. They are, in effect, small broadcasting stations which may be received in the ordinary way ‘through the ether,”’ by any nearby radio receiver.
Phono oscillators, heretofore considered harmless, are now coming for the scrutiny of the FCC and the FBI. Fear is felt that they may be, and are actually being used for Subversive Activity. Some new regulations with regard to these are in the making. We hope that these will help to keep the phono oscillators where they belong—in the hands of music lovers, for whom they were originally intended. *[1]
As far as CR is concerned, we believe that most of the oscillator type of record players do not belong in the hands of music lovers, either, though they may serve well enough for swing or jazz enthusiasts, to whom the finer nuances of a recording are matters of relative unimportance. They are good enough also for use with a poor radio set, since there is no need to deliver high-quality music to a set which will distort it before and at the loud-speaker.
Since this method of reproduction involves the use of a transmitter and receiver, interference and static will be noted under some conditions, depending upon strength of nearby stations, and moon. Hum may also be heard, even if the receiver is a good one, due to defects of the transmitter. One subscriber described the performance of the oscillator when the set was 12 feet away as worse than the reception from a distant, obscure station.
A music lover will want a type of record-plaver system capable of giving high-fidelity reproduction without adding unnecessary distortion. The faults of the phono-oscillator method of reproducing records through the radio set are numerous, so evident, indeed, that a writer in a trade magazine suggests that a wireless record player should have a switch arrangement so that when really good quality is needed, the pickup can be connected directly, by wires, to the set’s audio system.
The following will be of interest to those who have been tempted by the ease of installation and cheapness of the phonograph-oscillator type of record plaver and who may have wished for a fuller discussion of the subject than could be given in the brief space available in the Angual Cumulative Bulletin.
The oscillators are a very cheap and simplified form of small transmitting station sending out a high-frequency carrier wave which is modulated at audio frequencies by the electrical voltages introduced by the pickup of the record player.
The modulated carrier wave is transmitted to the radio set nearby, must be picked up by it, amplified at radio frequencies, de-modulated (detected), and then amplified again in the radio set’s audio amplifier. Each of these steps adds its own contribution of distortion.
In the wired type of pickup, however, the pickup is connected directly to the audio system of the radio, cutting out several links in the chain of transformations described, especially the faults of the poor and cheap “‘transmitter.”’
*[1]- In another place it is stated that illegal use of the oscillators has actually been noted in connection with the transmission of race track information, and that the Federal Communications Commission is planning to control phonograph oscillators by license, to prevent their use by Fifth Column and other subversive elements.
40.90Consumers'Research,Inc.