We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
July, 1939]
DESIGN PROBLEMS IN TELEVISION
The problem that arises is slightly different from the one that existed when radio broadcasting began. The system of transmission was obvious; and while different systems have been proposed and higher-quality transmission could be employed with the adoption of such proposals, the fact remains that equipment manufactured twenty years ago is still capable of producing intelligible results from presentday transmissions, and this has occurred despite the fact that the fidelity of these transmissions is vastly superior to that when radio broadcasting first began.
The situation is further relieved, in regard to broadcasting, with respect to the maximum allocated transmission -band width. The standards that were adopted twenty years ago provided for a ten-kilocycle separation of station carriers permitting a maximum modulation frequency of five kilocycles. The present policy of the Federal Communications Commission has been to assign carrier frequencies in a given area on widely separated channels. The tendency is to provide a limited number of stations serving a certain area at high signal level, and to the exclusion of more distant transmitters. Under this policy, the five-kilocycle bandwidth limitation fails to hold, and modern broadcasters continually provide program service of a much higher quality.
If a modern receiver is capable of reproducing the high-fidelity transmissions radiated by present-day broadcasters, the full advantage of years of engineering is obtained by the listener. But this service is not gained at the expense of those who have large investments in radio receiving equipment purchased years ago. In spite of the high-quality transmissions now radiated in contrast to the distorted signals for which these receivers were designed, the receivers still function satisfactorily.
Any television transmission must necessarily occupy a wide frequency band in comparison with standard broadcast transmissions;
FIG . 3 . Synchronizing generator panel .