Popular Science Monthly, December, 1919, unpaginated:

Navy  to  Broadcast  News  for  Benefit  of  Amateurs
SINCE October 5th, and by authority of the Director Naval Communications, a code broadcast-schedule, addressed to all amateurs, has been transmitted by the Naval Radio Station, 44 Whitehall Street, New York City, on 1500 meters. This broadcast immediately follows the 9:00 P. M. press schedule.
    Various items of interest to amateurs, such as the establishment of new stations, changes in wavelengths of high power stations, etc., are daily transmitted in this schedule.
    Copies of the code to be used may be obtained by any amateur by writing a request to the District Communication Superintendent, 44 Whitehall Street, New York City. When writing this request an amateur should give information as to his name; address; age; data concerning any military service; commercial experience, if any; class of operator's license, if any; number of words per minute he can copy; education; size and power of transmitting set, if he possesses one; type of undamped wave receiver, if one is installed; name of any radio organization or club to which he may belong.
    The object of this radio broadcast is to maintain the interest of radio amateurs and to train them in receiving code.
    Listen in for it tonight and see if you can catch it. Remember 9.00 P. M. in New York may not be 9.00 P. M. in your locality. New York time is Eastern time; Central time is one hour earlier; Mountain time, two hours earlier; Western time, three hours earlier. So listen in accordingly.
    Unless conditions happen to be unusually favorable, it may be that the more Western States will be unable to copy. In such localities this is a good chance to try out new two- and three-step amplifiers and see what they can do. In any event the broadcast is of interest and value for amateur, experimental and educational purposes.