The Purdue Exponent - Saturday, April 22, 1922
New License Issued Radio Station Here
"9YB" Classed as An Official Broadcasting Point and Designated "W.B.A.A."
W.B.A.A. is now the official call of the radio station at Purdue. Under the new radio laws, amateur transmitting stations have such restrictions placed upon them that the usefulness of the Purdue station was seriously endangered. To avoid these limitations, application was made and granted for a broadcasting license which permits the broadcasting station here to send out talks and concerts between 3 o'clock and 6 o'clock and between 7 o'clock and 9:30 o'clock any evening. The new license places the Purdue station on a par with the larger commercial broadcasting stations. The wavelength is to be 370 meters, the same as has been used in the past for continuous wave work. (Ed. - A wavelength of 370 meters is known in 2011 as 810kHz. Radio broadcasting, now measured in kiloHertz (frequency), was measured in meters (wavelength) until about the mid 1920's.)
The call 9YB will be used only for amateur and experimental work. At present there will be no regular schedule by which news will be broadcasted but it is planned to have in the near future a regular schedule for broadcasting.
The first message broadcasted under the new call letters W.B.A.A. was a message from the Secretary of Agriculture on "Arbor Day" which was sent out by Professor Achatz at 9 o'clock last night. The same message was sent out by all broadcasting stations in the United States simultaneously at 9 o'clock. It is expected that more people will hear this message than have ever heard one message before.
The Purdue Engineering Review, 1922, #17, p. 41
Radio Communication at Purdue, by N. C. Pearcy, E. E. '22
The first attempt to install a radio station at Purdue was made in connection with the thesis of R. A. Garrett and O. W. McIndoo, of the 1910 class. These men erected an aerial from the top of the stack to the north wing of the Electrical building and installed their apparatus in the room now used as a calibrating laboratory. The receiving apparatus was constructed by the men and the sending apparatus was adapted from the equipment used by Prof. H. T. Plumb for experimental work with high frequencies. Communication could not be established with any other station, so the experimenters turned their attention to tests of the various types of crystal detectors then used in practically all receiving sets.
In 1912, two seniors, A. E. Hague and G. R. Pigman, began another installation. A rope was passed over the Power House stack by means of a kite and a new aerial erected between this stack and the tower of the Electrical building. The station was moved to the office in the tower on the third floor of the Electrical building and a new helix was constructed. The equipment would not comply with the law in regard to wave length and decrement, so no license to send was obtained, but the receiving station, consisting of a loose coupler, a pair of three-thousand-ohm receivers, and a silicon detector, was successful in copying most of the spark stations in this country. An attempt was made to establish communication with the station at the University of Illinois, but failed because the Illinois station could not be heard by Purdue.
During the next year some additional work was done by R. E. Cleveland. A new rotary spark gap was constructed, but the sending equipment remained very inefficient because the transformer was designed for high-voltage testing and was not suitable for wireless use. In the winter of 1912-1913 the aerial was blown down from the stack and was replaced by one from the Electrical building tower to the corner of the Electrical laboratory. During the period from 1912 to 1915 the station was operated only as a receiving station and very little was done to place the sending set in operation.
In 1915 G. M. Wilson and E. H. Pullis undertook the improvement of the station and the installation of new transmitting equipment. An oscillation transformer and a new high-tension condenser, consisting of a group of milk bottles with salt water inside and outside, were constructed, as well as a new receiving set.
Previous to this time very little had been spent on wireless equipment, as no funds were available. In 1915 plans were made for the expansion of the station and its erection in a permanent location. Some additional equipment, including a 2 K. W. Packard transformer of a design suitable for radio work and a DeForest ultra-audion detector, was purchased. No progress was made, however, as a suitable room was not available. A room was completed in the basement of the Electrical laboratory in 1916, but the entry of the United States into the war put a ban on further operations in erecting a permanent station.
In 1918 the University entered actively into the work of instruction along radio lines in conjunction with the Signal Corps and a special course in radio communication was administered as suggest by the Army. Some additional material was purchased for this work and some equipment was supplied by the Signal Corps.
Later in 1918 the University undertook the instruction of 150 operators for the Army in connection with the training detachment maintained here. This quota was later increased to three hundred and the grade of instruction advanced to that of training for radio electricians. This work was carried on as section B of the S. A. T. C. until December. Extensive equipment was furnished by the Signal Corps for this work and some additional material was purchased by the University.
A temporary permit to operate a radio station was granted to the University in 1919 and immediate steps were taken to make a permanent installation. A receiving station was placed in operation and plans were made for the sending station. An aerial was erected between the tower of the Electrical building and a pole at the east end of the Laboratory, the spark gap was rebuilt, a new oscillation transformer of the pancake type was constructed a Weston thermocouple type ammeter was purchased, and various other equipment added. The call letters 9YB, with transmitting wave lengths of 200 and 375 meters, were assigned. The present spark transmitting set consists of a 2 K. W. Packard transformer, a lap-Eastham glass plate condense, and a rotary spark gap with a 15-inch bakelite disc on which are mounted twenty aluminum electrodes. The antenna current on the 375-meter wave length is about 6 amperes.
In 1919 F. F. Hamilton completed a handsome long wave receiving set in connection with the work for his E. E. degree. This set was presented to the University and is installed as a part of the permanent equipment of the station. A set of honeycomb coils is also available for long wave work, and French and German stations are frequently copied.
For short-wave receiving the University possesses a Paragon regenerative receiver. This is the type so popular with amateurs today and has given very satisfactory results. A detector and one-step amplifier panel has been constructed and a Magnavox loud-speaker purchased. A two-stage S. C. R.-72 type amplifier, which is a part of the radio equipment supplied to the R. O. T. C. by the government, is available, so that great amplification of signals may be obtained.
For continuous wave telegraphy and telephony, the station has a set constructed by R. H. Vehling, of the class of 1921, as a thesis assignment. Two 5-watt vacuum tubes are used as oscillators and two for modulation with a 500-volt generator supplying the plate current. An antenna current of about .8 ampere is obtained and the telephone has been heard approximately 600 miles.
Recently the old antenna was replaced by a six-wire cage antenna of the T type, stretched between the towers of the Electrical and Mechanical buildings. The horizontal portion has a total length of 100 feet and is 100 feet high. It is believed that this aerial will be far superior to any that have been used previously.
Prof. R. V. Achatz has been in charge of practically all communication work at Purdue, and the success of the station is largely due to his efforts. Two courses, one an elementary course and the other an advanced theoretical course, are offered to senior engineers who are interested in radio communication. Besides these two classes, Professor Achatz conducts a beginners' course one night each week for the benefit of any students or residents of LaFayette that may be interested.
Student operators have been assigned with H. T. Budenbom, class of 1922, as senior operator, and a five-night-a-week schedule has been maintained during the present year. The Purdue station communicates with stations in practically every state as far west as Colorado and is frequently heard by stations in western Canada and on the ocean. The number of messages handled is about sixty a month. 9YB was also instrumental in the establishment of the Western Conference Radio News Service, whereby news items are exchanged with the various schools in the Conference at regular intervals. The scores of all athletic contests at Purdue are sent broadcast for the benefit of the alumni in various sections of the country and a new broadcasting license, with the call letters WBAA, has recently been assigned to the station.
The plans for next year include a new 250-watt vacuum tube set, and provision will probably be made so that the Glee Club concerts, play-by-play reports of athletic contests, and other items of interest may be sent broadcast. It is to be hoped that many alumni will take advantage of this opportunity to keep in touch with their alma mater.