Tektronix, Inc.

Lloyd R Bristol

Gordon W Shank

Alfred K Hillman, Jr

David H Eby

Jeffrey A Kleck

A variable resolution system for a potentiometer converts the analog output of the potentiometer to digital steps which are multiplied to provide a number of digital output steps dependent upon the extent of potentiometer movement since last reversal. Upon each reversal, the number of output steps per input step is reduced to provide greater resolution.

Variable resolution control system

A system for correcting display distortion caused by CRT beam current changes in an oscilloscope system is disclosed. A Z-axis signal proportional to the CRT beam current is multiplied by two factors adjustable for either or both of X and Y axes and then added to the respective axis deflection signal which controls CRT beam deflection, thereby providing improved display quality.

Z-axis orthogonality compensation system for an oscilloscope

A delayed sweep oscilloscope having a word recognizer displays multi-digit parameters representing an event count necessary to initiate a delayed sweep, and a word to be recognized on oscilloscope data input lines. The numbers are modified digit-by-digit by rotating a first control knob to move a cursor on the screen to select a digit to be altered and then by rotating a second control knob to alter the selected digit. The control knobs are mounted on the oscilloscope front panel and when not used to modify these parameters, the control knobs may be used to control other oscilloscope functions.

Method and apparatus for adjusting displayed oscilloscope parameters

An oscilloscope displays a menu consisting of set of field codes and one configuration code set grouped with each field code. Each field code represents an oscilloscope operating parameter while each configuration code represents an alternative oscilloscope operating mode associated with the operating parameter. A configuration cursor is displayed underlining one configuration code in each field thereby indicating the current operating configuration of the oscilloscope. The configuration of the oscilloscope may be changed by first rotating a first control knob, mounted on the oscilloscope front panel, to locate a field selection cursor under a selected field code and then by rotating a second control knob to move the associated configuration cursor under the desired configuration code. The configuration of each field may be altered by selective operation of the two control knobs in this manner. The menu is displayed only when the oscilloscope configuration is to be changed and the two control knobs are used for other oscilloscope control purposes when the menu is not displayed.

Method and apparatus for controlling oscilloscope displayed menu

A lamp control circuit particularly suited for scale illumination in cathode-ray tube display devices provides stabilized lamp control impervious to temperature fluctuations for either constant or pulsed operating modes.

Scale illumination lamp control circuit for an oscilloscope

A multiplexed display interference compensation system for minimizing the apparent intensity modulation of an oscilloscope waveform display caused by closely spaced, individually imperceptible interruptions of the waveform required to maintain refreshed readout display is provided. The system includes a charge pump circuit for adding a current pulse to a waveform intensity control signal in response to a control signal from display multiplex control so as to increase the waveform intensity just after the interruption.

Multiplexed display interference compensator

An oscillographic device receives plural vertical inputs which are multiplexed to provide plural traces by means of the same electron beam. Switching times of the multiplexer are varied during the display to avoid gaps in waveform presentation when the period of the device's horizontal sweep is a near multiple of the switching period of the multiplexer.

Oscillographic device for displaying multiple continuous waveforms

Offset balancing method and apparatus for a DC amplifier including gain selection and polarity switching circuits are disclosed. During the offset compensation process, the amplifier input is connected to ground and its polarity is switched between the normal and inverted states before detecting the resulting output DC levels. The difference between such output DC levels is used to generate an offset compensation signal to be applied to the amplifier. The offset compensation process is repeated for each gain selection of the DC amplifier.

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Tigard, OR, United States of America

Lloyd R Bristol