公开(公告)号：US2520984A

公开(公告)日：1950-09-05

申请号：US72443647

申请日：1947-01-25

Applicant: MOTOROLA INC

Inventor： WILLIAMS FRED B ,  HILL FRED P

IPC: H01Q1/32 ,  H03H2/00

CPC classification number: H01Q1/3291 ,  H03H2/008

公开(公告)号：US2520987A

公开(公告)日：1950-09-05

申请号：US78128347

申请日：1947-10-22

Applicant: MOTOROLA INC

Inventor： WILLIAMS FRED B ,  HILL FRED P

IPC: H01Q1/32

CPC classification number: H01Q1/3291

公开(公告)号：US2520985A

公开(公告)日：1950-09-05

申请号：US78128247

申请日：1947-10-22

Applicant: MOTOROLA INC

Inventor： WILLIAMS FRED B ,  HILL FRED P ,  WILLIAM BLINOFF

IPC: H01Q1/32 ,  H01Q21/20

CPC classification number: H01Q1/3291 ,  H01Q21/205

公开(公告)号：US3571716A

公开(公告)日：1971-03-23

申请号：US3571716D

申请日：1968-04-16

Applicant: MOTOROLA INC

Inventor： HILL FRED P ,  RACE RICHARD T

IPC: H03H7/38 ,  H03H7/40 ,  H04B1/18

CPC classification number: H03H7/40 ,  H03H7/38 ,  H04B1/18

Abstract: A tank circuit for the aerial of a radio receiver includes a transformer located in a housing positioned at the bottom of the aerial with the primary winding electrically connected to the aerial. A voltage variable capacitor is connected across the primary winding. The secondary winding of the transformer is connected by a coaxial cable to the radio receiver which is remotely positioned from the aerial. A direct current potential from a potentiometer in the radio receiver is coupled through the coaxial cable to the voltage variable capacitor for tuning the antenna tank circuit over a predetermined frequency band. The selected RF signal in turn is coupled from the secondary winding of the transformer through the coaxial cable to the radio receiver.

公开(公告)号：US2520986A

公开(公告)日：1950-09-05

申请号：US78128147

申请日：1947-10-22

Applicant: MOTOROLA INC

Inventor： WILLIAMS FRED B ,  HILL FRED P

IPC: H01Q1/32

CPC classification number: H01Q1/3291

公开(公告)号：US2746006A

公开(公告)日：1956-05-15

申请号：US31483952

申请日：1952-10-15

Applicant: MOTOROLA INC

Inventor： HILL FRED P

IPC: H02J7/22

CPC classification number: H02J7/22

公开(公告)号：US2698907A

公开(公告)日：1955-01-04

申请号：US31484052

申请日：1952-10-15

Applicant: MOTOROLA INC

Inventor： HILL FRED P

IPC: H04B15/02

CPC classification number: H04B15/025