Page:CAB Accident Report, United Airlines Flight 16.pdf/23

 -21- History of the Salt Lake City Redio Range The first radio rexice* to be installed for Salt Lake City was a medium 3 pwer loop type range* located about 1-1/2 miles north of the Salt Lake City Airport. This rancu rús placed in operation in 1929 and served until 1933 when it was replaced on the sarde site by a full power vertical radiator type station." This station was modernized in 1938 under the direction of the then Administrator in the Civil Aeronautics Authority to produce the present full power simultanecus voice broadcast and range type station.* This modernization work was begun in August and completed in October, 1938. When the modernization of the Salt Lake City range was completed, tha A. radio rango is a raùio systep which radiates radin frequency fields in such a pattern that lires nual field strengths exist along predeter- mined courses over the earth's surface. These lines of equal field strength are called legs or courses of the vadio range, A listener, when on one of these legs, receives a steady dash, referred to as an "on course" signal, On one side of the leg he would receive an "A" (dot-dash) and the area in which this signal is received is referred to as an "A quadrant,* on the other side of the leg he would receive an "N" (dash-dot) and the area in which this signal is recoived is referred to as an "N quadrant." Four- courses are produced by each radio range and in the most simple installar tions these courses lie at 90 degrees to each other. However, hy the.. introduction of certain circuit arrangements, the courses can be made to assume angles other than 90 degrees and this alignment is called "squeezing" or "uending: depending upon the pattern formed. Identification signals are transmitted in both the "." aná "N" quadrants so that a listener can determine to what range he is listening. The identificatici signal is also heard while listening to the on course signal. The Civil Aeronautics Administration cperates 278 radio range stations along the civil airways throughout the United States. It A medium power range is one of three power classifications into which the Civil Aeronautics Administration ranges may be divided, These classifica- tions are: Full power - greater than 150 watts Medium power- 50 to 150 watts LOW power - less than 50 watts ess than A loop type range is a radio range which employs loop antennas for its råd1- ating system, while a vertical radiator type range 18 ane which employs towers or vertical radiators for it's rediating system. A simultaneous voice broadcast and range type station is a radio range over rh fch radio telephone messages can be transmitted at the same time the station is radiating range signals. Such's station also makes weather broad nasts on a schedulod basis. SWANA