TRANSDUCER AND INTERPHONE SYSTEM FOR OPERATION IN HIGH-AMBIENT NOISE.
Abstract
The report discusses work performed toward development of an improved Transducer and Interphone System for operation in high-ambient noise. Work progressed toward development of a tubular microphone shield. Included was an evaluation of several acoustical materials, and the fabrication of a practical shield. Earphone enclosures with LFC (Low Frequency-Coupled) volumes were constructed and tested, and results are presented herein. Performance of the present communications system was evaluated and compared with expected performance of a CBS Laboratories-designed system. Psychoacoustic tests were performed to relate articulation index with phonetically-balanced word testing. Basic electronic design of the system was completed. Each system comprises three crewmember units and an interphone amplifier. Circuits for achieving automatic gain control and squelch operation are described, including four methods for accomplishing automatic gain control. Detailed circuit descriptions as well as system designs were incorporated into the interphone amplifier, and are also described. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 30, 1965
- Accession Number
- AD0626618
Entities
People
- Alfred L. Dimattia
- Allan J. Rosenheck
- Emil L. Torick