Richard James Conrad

US Patent:

44778031, Oct 16, 1984

Filed:

Nov 2, 1981

Appl. No.:

6/317090

Inventors:

Richard J. Conrad - Hamilton MA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

G09G 116

US Classification:

340722

Abstract:

A system for displaying a voltage wave wherein the wave and a delayed version of the wave are separately compared with a voltage ramp that is proportional to the position of an electron beam is changed between the point where the voltage ramp equals the voltage of the voltage wave and the point where the voltage ramp equals the voltage of the delayed version of the wave.

US Patent:

51329395, Jul 21, 1992

Filed:

May 24, 1991

Appl. No.:

7/705192

Inventors:

Richard J. Conrad - Hamilton MA

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

G03B 4206

US Classification:

367105

Abstract:

This invention relates to low transient switching apparatus, and more particularly to switching arrays of low transient switching circuits which are adapted for use to substantially continuously focus transducer channel outputs in an ultrasonic scanning system. A separate switching array is provided for each channel. Each array has a switching circuit with an output for each focusing delay line tap to which a signal on the channel may be applied. Each switching circuit provides a substantially constant D. C. current output regardless of the state of the circuit. Array outputs for each delay line tap are summed, and the summed outputs are applied as the input to the tap. The DC current inputs to all taps are maintained substantially equal, preferably at zero DC current.