H03J TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
Introduced: September 1968
Classification Context
- Section:
- ELECTRICITY
- Class:
- ELECTRONIC CIRCUITRY
- Subclass:
- TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
Description
H03J covers devices and methods for adjusting the resonant frequency of LC circuits and selecting among multiple resonant circuits. This includes mechanical tuning mechanisms (variable capacitors, inductors), electronic tuning approaches (varactor diodes, voltage-controlled oscillators), and circuit selection switching. The class encompasses applications in radio receivers, transmitters, and frequency-selective filters where precise frequency control or channel selection is required. Related but separate classes handle specific oscillator designs (H03B) and general frequency control or synchronization circuits (H03L).
Related Keywords
5 direct subcodes
Child Classifications
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- H03J 1/00 Details of adjusting, driving, indicating, or mechanical control arrangements for resonant circuits in general
- H03J 3/00 Continuous tuning
- H03J 5/00 Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner
- H03J 7/00 Automatic frequency control; Automatic scanning over a band of frequencies
- H03J 9/00 Remote-control of tuned circuits; Combined remote-control of tuning and other functions, e.g. brightness, amplification
Top Applicants
Top 10 applicants by patent filingsfor class H03, 2013–2023, worldwide · Source: EPO PATSTAT
- QUALCOMM US 5,625
- SAMSUNG ELECTRONICS COMPANY KR 5,496
- MURATA MANUFACTURING COMPANY JP 5,478
- HUAWEI TECHNOLOGIES COMPANY CN 3,383
- INTEL CORPORATION US 3,091
- TEXAS INSTRUMENTS US 3,070
- MURATA MANUFACTURING COMPANY 2,722
- SKYWORKS SOLUTIONS US 2,290
- SEIKO EPSON CORPORATION 2,177
- IBM (INTERNATIONAL BUSINESS MACHINES CORPORATION) US 2,158