Walter D Fields

US Patent:

54020190, Mar 28, 1995

Filed:

Aug 6, 1992

Appl. No.:

7/926101

Inventors:

William S. Drummond - Cornelius OR
Arthur J. Metz - Gervais OR
Walter D. Fields - Beaverton OR

Assignee:

Tektronix, Inc. - Wilsonville OR

International Classification:

H03K 506

US Classification:

327237

Abstract:

Apparatus for generating a phase startable clock signal, comprises an oscillator for providing a continuous sinusoidal input signal, a control signal source for providing a control input signal having a transition between a first state and a second state at a selected time during the signal epoch of the sinusoidal input signal, and a phase splitter, track and holds, multipliers and a summation device for operating on the sinusoidal input signal with the control input signal to produce a sinusoidal output signal commencing with a predetermined phase at a predetermined time relative to the transition.

US Patent:

48210072, Apr 11, 1989

Filed:

Feb 6, 1987

Appl. No.:

7/011972

Inventors:

Walter D. Fields - Beaverton OR
Gary K. Larkins - Beaverton OR

Assignee:

Tektronix, Inc. - Beaverton OR

International Classification:

H01P 308

US Classification:

333238

Abstract:

An improved strip line component and method of manufacture are disclosed that permit strip line circuits to be packaged in component form and to be soldered directly to conventional circuit boards. Electrical contact pads are formed on the side of the strip line component during fabrication by drilling holes through the multilayer laminar assembly and plating the holes with a conductive material. The laminar assembly is then cut along lines that intersect the holes, thereby exposing plated indentations along the sides of the cut component. The component so cut can then be soldered to a circuit board using the plated indentations. The method is well adapted to the economical manufacture of large numbers of identical components.

US Patent:

50686143, Nov 26, 1991

Filed:

Nov 5, 1990

Appl. No.:

7/608880

Inventors:

Walter D. Fields - Beaverton OR
Linley F. Gumm - Beaverton OR

Assignee:

Tektronix, Inc. - Beaverton OR

International Classification:

G01R 3102

US Classification:

324534

Abstract:

An improved swept frequency domain reflectometry instrument has an input/output terminal coupled to one end of a cable. A radio frequency at the input/output terminal is converted to an intermediate frequency using a swept local frequency. The radio frequency is derived from the swept local frequency and a variable offset frequency. A controller controls the variable offset frequency, monitoring the amplitude of the intermediate frequency. A period counter counts the intermediate frequency at a first maximum response of the intermediate frequency and further counts the offset frequency at a second maximum response of the intermediate frequency. The location of a discontinuity in the cable is calculated from the counted frequencies.