DIFF Main Group
H04R 21/00 Variable-resistance transducers (gaseous resistance transducers H04R23/00; magneto-resistive transducers H04R23/00)
Introduced: September 1968
Title
Titles differ between systems:
IPC: Variable-resistance transducers
CPC: Variable-resistance transducers (gaseous resistance transducers H04R23/00; magneto-resistive transducers H04R23/00)
Full Title
Full titles differ between systems:
IPC:
Variable-resistance transducers
CPC:
Variable-resistance transducers (gaseous resistance transducers H04R23/00; magneto-resistive transducers H04R23/00)
IPC and CPC are identically structured here. All 2 subcodes exist in both systems.
Child Classifications
Navigate with arrow keys, Enter to open
- H04R 21/04 Gramophone pick-ups using a stylus; Recorders using a stylus IPC+CPC Available in IPC and CPC