Patents by Inventor James M. Motherbaugh

James M. Motherbaugh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5157338
    Abstract: The invention described a pocket size antenna VSWR indicator having a self-contained low level wideband RF signal source which is applied to an antenna under test through a four arm RF resistive bridge circuit. The bridge circuit has been designed to be very accurate and reliable and provides a novelly positioned reference against which the reflection co-efficient of the transmission system is compared to reliably indicate the VSWR of the system. The bridge circuit provides a flat response over the desired wideband frequency range and over the range of antenna impedances which may be encountered. The RF null or bridge balance is detected in a radio receiver or transceiver tuned to the desired operating frequency, from which an indication of antenna VSWR may be provided. The antenna VSWR may be indicated in a variety of way, such as by means of a numbered or colored dial, a plurality of LEDs or an audio tone shift against an internal reference.
    Type: Grant
    Filed: January 22, 1991
    Date of Patent: October 20, 1992
    Assignee: James M. Mothersbaugh
    Inventors: James M. Motherbaugh, John E. Keim