发明授权
US4408347A High-frequency channel selector having fixed bandpass filters in the RF section 失效
在RF部分中具有固定带通滤波器的高频信道选择器

High-frequency channel selector having fixed bandpass filters in the RF
section
摘要:
A high-frequency channel selector for a television receiver including at least one fixed filter having a predetermined passband, and a high-frequency mixer. The antenna for the television receiver receives radiated electromagnetic signals including, for example, a plurality of television channels. The fixed filter has an input coupled to the antenna and filters one fixed frequency spectrum of television channels from the received signals. The mixer has inputs coupled to simultaneously receive the fixed frequency spectrum of channels and mixing signals of a high selectable frequency. The high selectable frequency shifts selectable channels of the spectrum to high intermediate frequency substantially greater than 45 MHz.
信息查询
0/0