Ultra Speed Recording Technique
C. J. LeBel · The Journal of the Acoustical Society of America · 1951
The new technique permits ink recording at 5000 db per second, or ten times the pen speed possible with the high speed level recorder. This technique uses a linear-to-logarithmic converter, a linear rectifier, and a dc amplifier driving a direct writing oscillograph. Temperature stability, linearity, and transient response are discussed. The problem of achieving adequate transient performance in the logarithmic-element driving amplifier is emphasized. Examples of recordings of various types are shown, illustrating the effect of using various pen speeds between 600 and 5000 db per second.