초록 ▼

A television tuning system includes UHF and VHF signal paths each tuned by a tuning voltage and coupled to a common signal path by a diplexer. So that UHF signals will be attenuated so to not cause interference with a VHF channel signal which is selected to be viewed, the UHF filter is detuned when

A television tuning system includes UHF and VHF signal paths each tuned by a tuning voltage and coupled to a common signal path by a diplexer. So that UHF signals will be attenuated so to not cause interference with a VHF channel signal which is selected to be viewed, the UHF filter is detuned when a VHF channel is selected. Detuning the UHF filter is accomplished by modifying the tuning voltage for the UHF filter responsive to the VHF band-switching voltage.

대표청구항 ▼

A tuning system for a television receiver comprising: first and second signal paths for receiving radio frequency signals disposed in respective first and second frequency bands, each of said signal paths including filter means for providing frequency selective characteristics controllable in respon

A tuning system for a television receiver comprising: first and second signal paths for receiving radio frequency signals disposed in respective first and second frequency bands, each of said signal paths including filter means for providing frequency selective characteristics controllable in response to a tuning signal, said filter means of said first signal path including first and second resonant circuits responsive to said tuning signal; tuning control means for developing said tuning signal to select one of said radio frequency signals within said first and second frequency bands and for developing a band signal indicative of the one of said first and second frequency bands which includes said selected radio frequency signal; combining means for combining signals from said first and second signal paths onto a common signal path; means for applying said tuning signal to said filter means of said first and second signals paths; and means coupled to said first signal path and responsive to said band signal for modifying said tuning signal applied to said first and second resonant circuits by different amounts when said selected radio frequency signal is included in said second frequency band.