The Purdue Exponent - Thursday, September 11, 1941
WBAA Will Conduct Publicity Broadcast At Student Book Exchange Today At 2:15
Student book exchange, in the south ballroom of the Union, will be publicized today in a fifteen minute broadcast over WBAA at 2:15, when a traveling microphone will be brought in. Students and workers in the exchange will be interviewed at this time.
According to Bill Hepburn, manager, the book exchange has done close to $2,000 worth of business, and crowds and books are still pouring in.
There are, however, several books which are much in demand and which remain conspicuously absent from the book exchange shelves. These books are for: Calculus, Math 3 and 4, Physics 22, G. E. 11, Met. 153, and Math 1. An urgent call has been put out that any available copies of these books be brought in as soon as possible.
Books will be received until Saturday, September 13, and the selling will close on Friday, September 19. The watchword now, for the student book exchange is "Hurry, hurry, hurry," for those who wish to buy or sell. A reservation list is available for those who wish to buy books not immediately on hand.
The exchange will start paying students the last of next week for books sold. w.g.h.
The Purdue Exponent - Wednesday, September 17, 1941
WBAA Will Hold Auditions For Actors This Afternoon
WBAA announces that auditions for radio announcers and actors will be held in the main studio under the Music Hall this afternoon at 4 o'clock.
Auditions will be made, complete with scripts and microphones. Applicants will be judges on tone quality, pitch, enunciation, and acting ability. The only stipulation made is that the candidate have a 3.5 index.
The Purdue Exponent - Saturday, September 20, 1941
New WBAA Transmitter Starts Operation Monday by Bob Boswinkle
After several months of construction and testing, the new WBAA transmitter is about to be used for regularly scheduled radio programs. It will begin functioning Monday when WBAA starts operating 12 hours a day in place of its present schedule of broadcasting from 12 to 4 p.m. every afternoon.
Testing of the new transmitter has been going on for the last two months. In that time it has sent out recorded music from 1 until 6 every morning. As part of the test, the broadcasts have been picked up at such distant places as points in Alabama, Colorado, and Ontario, Canada.
New With Old
Auxiliary equipment, acquired along with the new studios in the Hall of Music, has been operating with the old transmitter ever since the studios were moved from the offices in the EE building. The new equipment, however, gave poorer quality broadcasts with used with the old transmitter than when it was used with the old equipment. The superiority of the new equipment can now be utilized when it starts to function in conjunction with the new transmitter.
Wider Range Means Fidelity
The decided improvement in the quality of the programs that will be received can be illustrated by the fact that the old transmitter has an audio range of 60 to 1500 cycles. A tuba his notes as low as 40 cycles which, obviously, couldn't be transmitted. Difficulty in transmitting very high notes such as those of a violin also has been encountered with the old equipment.
Trouble of this sort will be eliminated in the future, for the new transmitter has an audio range of 100 to 4,000 cycles, adequate to carry a wide range of notes.
Public interest has been aroused over the erection of the three towers, located five miles south of town. Each of these towers is 257 feet from the ground and contains the directional antenna. The new transmitter is also located there.
The Purdue Exponent - Sunday, September 20, 1941
WBAA Completes Plan To Go On 12-Hour Day
Plans are now completed for the operation of the University radio station WBAA, transformed into a full-grown transmitter with full-time operation privileges. Broadcasting at the same frequency of 920 kilocycles, WBAA will bring campus programs and news to the air from 10 a.m. until 10 p.m., operating at 5,000 watts until sunset and 1,000 watts during the evening.
WBAA, the oldest broadcasting station in Indiana, first went on the air in 1922. In recent years, the station has been operating from the electrical engineering building under a limited license. Under the new set-up WBAA will hold a license for unlimited hours and will utilize the most modern equipment, broadcasting from the Hall of Music studios.
Elliott to Speak
President Elliott will be the first to go out on the air waves over the new system. He will speak at opening of the first day of operations. According to the present schedule, the new transmitter will go into regular service at 10 a.m. tomorrow, at which time President Elliott, and Prof. C. F. Harding, head of the school of electrical engineering who has been instrumental through the years in the progress of the station, will be heard. However, while arrangements are complete here, there is some doubt as to whether the Federal Communications Commission will send notification of the granting the license in time to permit starting of the new program before later in the week. When the red tape is unwound, Dr. Elliott and Prof. Harding will inaugurate the new station.
Air Time Doubled
The doubling of the air time will permit the addition of many new programs and services to WBAA's schedule. When the new program goes into effect, news broadcasts will be heard daily during the six days per week of operation at 10 a.m., 3 p.m., 5:50 p.m. and 9:50 p.m. Among the new programs will be a weekly broadcast by the musical organizations under the direction of Al Steward, during which one of the four groups, Glee Club, Concert Choir, University Choir and University Orchestra, will perform. Many old features will be given more time on the air, in particular classroom broadcasts, the Ag Forum, and similar programs.
A number of sociology, economics, drama, and history classes are scheduled for regular appearances. Students are warned, however, that painless absorption of their respective classes over the air will not be considered satisfactory substitute for presence before the microphone. f.o.b.
The Purdue Exponent - Friday, September 26, 1941
Freshmen Singers To Broadcast Today
Inaugurating a new series of student radio programs, the Musical Organizations will present the outstanding freshman members of the Glee Club and the University Choirs in a vocal and piano variety entertainment at 4:30 p.m., today over station WBAA. Similar musical broadcasts will be heard over the station on succeeding Friday afternoons at the same hour.
Featured on the initial program are Wilma Palmer, soprano; Virgina Ulrey, soprano; Marilyn O'Hara, contralto; Barbara Heath, contralto, Ruth Ralston, contralto; Sidney Smith, tenor; Bill Morgan, tenor, William Kennedy, baritone; and David Simpson, who will play a piano medley. g.w.b.
WBAA Announces 45 New Workers For Enlarges Staff
WBAA announced yesterday the new members of the staff who were auditioned some time ago. The staff has been enlarged this year to take care of the increased time on the air. The script writers staff is a new staff this year.
The new members of the staffs include the following: David Barta, Lawrence Boger, Rosemary Anne Boyd, Barbara Ann Bradley, Richard J. Brown, Marianna Duke, Geraldine Floyd, Jane Grimmer, Helen Henn, Stan Hirschfield, Gordon Jenkins, Dick Kelly, Robert Knapp, Jean Lauer, William Henry Lange.
Betty Lewis, Marvin L. Lynch, Thomas Keys McCrum, Bonnie McPherson, Justin R. Meacham, Joanne Menefee, Billie Nicholson, Robert G. O'Brien, H. A. Osborne, Chris Schenkel, Margaret Slate, S. N. Stevens, L. M. Steltenhenz, Bufor A. Tribble, Dorkas Tribble, Lois Jane Vaughn, Anne Vogler, Mabel Vaughn, Bob Visein, Carolyn Wood, Norman Merrick, Betty Jane Jansing, Mollie Flager, George Zissis, Martha Lou Stewart.
The Purdue Exponent - Wednesday, October 8, 1941
WBAA To Broadcast Art Guild Program Tonight
Through the cooperation of radio station WBAA, the Student Art Guild will present the second in its series of radio programs entitled "What Is Art To Me?" tonight at 8 o'clock.
The program will be in the form of a dramatic news broadcast, concerning events on several Big Ten campuses in connection with art, news pictures from Washington, D. C., the modernistic church at Columbus, Indiana and the latest art news here.
The next Art Guild meeting will be held tomorrow afternoon at 4:30 in the Union Puttering Shops. w.e.v.
The Purdue Engineer, Vol. 37, No. 4, p. 86, January 1942
WBAA Expands by Frank J. Clack, E.E. '44
WBAA, "Indiana's first radio station," is now equipped with the best of studio and transmission facilities.
Shortly after the first World War, Purdue University established an experimental broadcasting station. This station has been moved from one location to another throughout the past twenty years, and during the process of moving, the power of the station has gradually increased to one thousand watts. This fall the power of WBAA was raised to five thousand watts by authority of the Federal Communication Commission, and the studios were moved into the basement of the new Music Hall. Also, the transmitter was moved into the country about six miles southeast of West Lafayette.
Engineering students of Purdue have been waiting for some information on the new studios and here is the first authentic information.
WBAA has three studios in their new location. One is a small announcing studio designed for station break announcements and news. The second and largest studio is designed for orchestral or dramatic presentations. The third is an audience studio equipped with a stage. Each of the studios has three permanent microphones which are operated from the control panel. Here a studio is selected and the three microphones are automatically switched to three faders and switches for microphone control. These three faders and switches serve all three studios; they are set up for use on one studio at a time by pushing the studio switch, but this may be changed to suit the operator by use of the jack panel. Turntables on which transcriptions are played are beside the control board. There is one master fader for the two turntables and two more faders for the remote lines. The remote line is selected by one of the lever key switches after being set up on the jack panel. There are three positions of the remote line switch. One position is to feed the program proceeding the remote program to the remote announcer; the second position is for hand phone communication between the operator and the control operator; the third position is to feed the remote program into the control panel. On the permanent remote line to the Agricultural Building, the remote box has a light on it which lights when the program cue is turned off signifying to the announcer that he is to "go ahead". Besides the switch for this and other permanent remote lines, there are switches for temporary lines.
WBAA has a unique monitoring system. The usual set up for a monitor is to tap on the final stage of the speech amplifier and thence to a monitoring speaker and meter. There is one disadvantage to this system--the studio never knows whether the transmitter is on the air or not. WBAA has two monitoring systems. One is the type just described; and the other consists of a radio which picks up the signal sent out by the transmitter and amplifies it for use in the monitoring equipment. There is a switch on the control panel which enables the operator to choose whichever system he wishes. Two systems are used for comparison of the signal leaving the studio and transmitter. Most of the monitoring is done by the radio system. There are special operator controlled circuits in each studio for the purpose of mixing the sound from two studios. The studio cue speakers on these circuits go off automatically when a microphone in that studio is turned on.
In the back of the control room there are three relay racks. In the top of one of these are mounted the preamplifiers for the permanent studio microphones. There are ten preamplifiers which may be connected, by using the patch panel, to any one of the nine permanent studio microphones or the talk back microphone. Each one of the preamplifiers has two switches on the front panel and by pressing these switches the plate current and the plate voltage may be read from any preamplifier.
In the second relay rack are the line amplifiers and the monitoring receiver. At the top of the rack is the speech amplifier, which is used to amplify the audio signal after it leaves the control panel and bring the level high enough so that it may be sent to the transmitter. Below the speech amplifier is the monitoring amplifier. This amplifier, after receiving the signal from the speech amplifier, increases the signal so that it may be heard in the loud speakers which are in strategic positions about the studio. The studio-control room talk back system amplifier is the next down the rack. Foreseeing the need of an emergency amplifier and the convenience of an audition amplifier, provisions have been made for installation of such a piece of equipment. This amplifier will have a mixer panel separate from the control panel and built into the amplifier rack. This will keep the audition circuits off the control panel.
The monitoring receiver is located in the bottom of the amplifier rack. You have probably seen the aerial on the top of the Music Hall which is used to pick up the signal from the transmitter. The receiver has a low drift selector stage and there is a red pilot light on the front panel. This light is lit whenever the transmitter is on the air and tells the operator whenever the transmitter is on or off the air when he is not monitoring be means of this system.
The third relay rack contains all of the power supplies for the control room. At the top of the rack is a six volt d. c. power supply for the relay system. This power pack employs a copper oxide rectifier. There is also a counter to record the number of times that the carrier is overmodulated, a device used to check the operators. Next is the power supply for the speech, monitor, and talkback amplifiers, followed by the power supply for the preamplifiers and the monitoring system.
Directly below the control room there is a shallow basement. This basement serves as a terminating point for all incoming and outgoing lines. There is no wiring around the walls of the control room; it is all underneath the floor in the basement where it is easily reached for repair and revision.
The transmitter, located on one of the Purdue farms, is a five kilowatt Collins, model 21A. It is controlled by a crystal oscillator which is followed by a three stage buffer. The first two stages of the buffer are untuned and the last stage is tuned to the crystal frequency. The output of the buffer is used to drive a pair of RCA 813's which are connected in push-pull. The final stage, which is driven by the RCA 813's, is a single-ended class C amplifier employing an RCA 892. The class B modulator consists of two RCA 202's which are resistance coupled to a pair of 891's.
As most of you know, WBAA reduces power to one thousand watts at night. At this time, the directional antenna system is used. It consists of three vertical towers set on a straight line. By varying the phase of the two outer towers with respect to the center tower, the pattern of coverage may be altered to suit the F.C.C. regulations.
The author wished to express his gratitude for the assistance of Mr. Ralph Townsley and Mr. J. W. Ditamore in the preparation of this article.