| 455 / | HD | TELECOMMUNICATIONS |
| 130 | DF | RECEIVER OR ANALOG MODULATED SIGNAL FREQUENCY CONVERTER {24} |
| 150.1 | DF | .~ Signal selection based on frequency (e.g., tuning) {13} |
| 196.1 | DF | .~.~ Including variation of local oscillator frequency {1} |
| 197.1 | | .~.~.~ By simultaneous control with signal selection {3} |
| 197.2 | DF | .~.~.~.~> Variable capacitor tuned {1} |
| 198.1 | DF | .~.~.~.~> Including distributed parameter control device |
| 199.1 | DF | .~.~.~.~> Discrete frequency types (e.g., channel switching) |