With Voltage Or Current Conversion (e.g., D.c. To A.c., 60 To 1000) Patents (Class 324/120)
  • Display circuit for battery powered digital meter
    Patent number: 3990008
    Abstract: A digital meter incorporates a circuit which senses the input voltage and automatically energizes a digital readout device only if the input voltage is greater than a predetermined absolute value.
    Type: Grant
    Filed: March 12, 1975
    Date of Patent: November 2, 1976
    Assignee: Sencore, Inc.
    Inventor: Marlin D. Westra
  • Method of indicating and/or recording electrical quantities and indicating respectively recording apparatus embodying said method
    Patent number: 3970931
    Abstract: A method and an apparatus are described for indicating and/or recording electrical quantities, the desired and actual values being converted into pulses whose repetition frequencies are proportional to the actual and desired quantities. The difference between the two pulse frequencies controls a stepping motor, whose shaft drives the indicating or recording element.
    Type: Grant
    Filed: July 5, 1974
    Date of Patent: July 20, 1976
    Assignee: U.S. Philips Corporation
    Inventor: Ivan Novak