A. <u>Objectives</u>. After a careful consideration of the problems involved, the writer formulated the following objectives: (1) To determine the variation of lamp characteristics with life for various wave forms. (2) To determine the variation of lamp characteristics with voltage for various wave forms. (3) To attempt to correlate the variation of lamp characteristics to the crest factor of the voltage wave employed. B. <u>Equipment</u>. This investigation was performed on 100 watt, type A21 115-volt lamps manufactured by Sylvania Electric Products Inc. The following information obtained from the lamp manufacturer was used as a basis for all calculations. <u>Initial Lumens</u> 1635 <u>Initial Lumens Per Watt</u> 16.35 <u>Rated Average Hrs. Life</u> 750 The wave forms used were produced by means of a General Electric Sine Wave Generator, Model 15A224, consisting of a 10 horsepower, 3600 rpm, direct current motor directly coupled to five alternators. These alternators produced frequencies of 60, 120, 180, 300, and 420 cycles per second respectively. The output of the alternators were connected in series as desired by means of a specially designed switch board. The alternator fields were excited directly from the output of a 3 phase, half wave, 250 volt, 75 ampere, ignitron manufactured by the Westinghouse Electric Corporation. The value of the lamp intensity in foot-candles were read by means of a Western photronic cell. The photronic cell used was equipped with a visual-correction filter so that its response is closely similar to the visibility curve of the human eye. / Master of Science