US PATENT SUBCLASS 381 / 181
.~.~.~.~ Differential


Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use



381 /   HD   ELECTRICAL AUDIO SIGNAL PROCESSING SYSTEMS AND DEVICES

150  DF  ELECTRO-ACOUSTIC AUDIO TRANSDUCER {18}
369  DF  .~ Microphone capsule only {10}
179  DF  .~.~ Resistive {1}
180  DF  .~.~.~ Granular or carbon {1}
181.~.~.~.~ Differential


DEFINITION

Classification: 381/181

Differential:

(under subclass 180) Subject matter having two sound responsive resistance elements one positioned on either side of a central diaphragm.