1
Britton Jr Ralph H: Pulse drive circuit for coils of dental impact tools and the like. Hufnagel Fred M, June 27, 1972: US3673475 (174 worldwide citation)

A drive circuit for dental percussion tools or hammers and the like including a power supply coupled with a timing circuit which provides suitable output pulses of selectable frequency. The output of the timing circuit is connected to a recoil-drive pulse forming circuit which includes one shot mult ...


2
Britton Jr Ralph H: Swept frequency measurement system. Pacific Measurements, Limbach Limbach & Sutton, September 9, 1975: US3904959 (14 worldwide citation)

A calibration curve for a test circuit alone is first memorized by the system and is then automatically subtracted from subsequent response measurements of a test device placed in the test circuit to give just the response characteristics caused by the test device. In one preferred embodiment, the s ...