公开(公告)号：KR830001338B1

公开(公告)日：1983-07-09

申请号：KR780002089

申请日：1978-07-05

Applicant: TEXAS INSTRUMENTS INC

Inventor： ASH DARRELL L

IPC: H04B1/16

Abstract: The improved channel selector includes a MESFET mixer in combination with an acoustic surface wave device filter. The MESFET mixer simultaneously receives a plurality of channels and mixing signals of a selectable frequency, and in response thereto frequency shifts selectable channels to a predetermined center frequency. The surface wave device filter provides essentially all of the channel selectivity of the receiver.

公开(公告)号：CA1136222A

公开(公告)日：1982-11-23

申请号：CA371747

申请日：1981-02-25

Applicant: TEXAS INSTRUMENTS INC

Inventor： ASH DARRELL L

IPC: H03J7/04

Abstract: MESFET DEVICE SURFACE-WAVE-DEVICE CHANNEL SELECTOR An improved channel selector for a television receiver which includes a metal semiconductor field effect transistor, i.e. MESFET, mixer in combination with an acoustic surface wave device filter. The MESFET mixer simultaneously receives a plurality of channels and mixing signals of a selectable frequency, and in response thereto frequency shifts selectable channels to a predetermined center frequency. The MESFET mixer has almost perfect square law characteristics, and accordingly introduces extremely small distortion into the system. The acoustic surface wave device filter has an input coupled to the output of the MESFET mixer. The surface wave device filter provides essentially all of the channel selectivity of the receiver.

公开(公告)号：CA1110356A

公开(公告)日：1981-10-06

申请号：CA305989

申请日：1978-06-22

Applicant: TEXAS INSTRUMENTS INC

Inventor： ASH DARRELL L

IPC: H03J7/18 ,  H03B5/18 ,  H03B5/32 ,  H03B5/36 ,  H03D7/12 ,  H03D7/16 ,  H03H9/145 ,  H03H9/64 ,  H03J5/02 ,  H03J7/08 ,  H04B1/26 ,  H04N5/44

Abstract: MESFET DEVICE SURFACE-WAVE-DEVICE CHANNEL SELECTOR An improved channel selector for a television receiver which includes a metal semiconductor field effect transistor, i.e. MESFET, mixer in combination with an acoustic surface wave device filter. The MESFET mixer simultaneously receives a plurality of channels and mixing signals of a selectable frequency, and in response thereto frequency shifts selectable channels to a predetermined center frequency. The MESFET mixer has almost perfect square law characteristics, and accordingly introduces extremely small distortion into the system. The acoustic surface wave device filter has an input coupled to the output of the MESFET mixer. The surface wave device filter provides essentially all of the channel selectivity of the receiver.