公开(公告)号：US3582794A

公开(公告)日：1971-06-01

申请号：US3582794D

申请日：1968-11-18

Applicant: GEN MOTORS CORP

Inventor： SMITH WAYNE A

IPC: H03J7/18 ,  H04B1/16 ,  H04B1/32

CPC classification number: H04B1/1646 ,  H03J7/18

Abstract: A circuit to permit an FM radio receiver equipped for stereo reception and having a search mechanism for scanning the FM band to respond only to stereo broadcasts. The detector signal and pilot signal are combined to operate a search latch mechanism only when both are present.

公开(公告)号：US3078123A

公开(公告)日：1963-02-19

申请号：US2932660

申请日：1960-05-16

Applicant: GEN MOTORS CORP

Inventor： FRAME THOMAS B ,  MALETZKE ARNOLD J ,  SMITH WAYNE A

IPC: B60B7/02

CPC classification number: B60B7/02

公开(公告)号：US3633111A

公开(公告)日：1972-01-04

申请号：US3633111D

申请日：1969-10-22

Applicant: GEN MOTORS CORP

Inventor： SMITH WAYNE A

IPC: H03J7/30 ,  H04B1/32

CPC classification number: H03J7/30

Abstract: A superheterodyne radio receiver is provided for receiving RF signals over a reception frequency spectrum. The radio receiver includes a signal-seeking tuner having a drive mechanism for defining the reception frequency of the radio receiver as a function of the movement of the drive mechanism. The tuner is responsive to a start signal to initiate movement of the drive mechanism to vary the reception frequency of the radio receiver over the reception frequency band. Further, the tuner is responsive to a stop signal to terminate movement of the drive mechanism after the drive mechanism has coasted to a stop over a stopping-frequency range. A control circuit includes a transformer having a primary tuned circuit and a secondary tuned circuit each exhibiting a slightly different resonant frequency. A limiter circuit combines with the control circuit to provide frequency response curves for the IF signal of the radio receiver which are compressed with respect to overall magnitude and skewed with respect to peak frequency. As a result, an IF control signal is developed having an amplitude which exceeds a trigger level only when the nominal magnitude of the received RF signal exceeds a minimum reception level, and only when the reception frequency of the radio receiver differs from the carrier frequency of the received RF signal by an amount approximately equal to the stopping frequency range of the tuner drive mechanism. A stop signal is applied to the tuner when the amplitude of the IF signal exceeds the trigger level so that the drive mechanism coasts to a stop at a frequency approximately equal to the carrier frequency of the next received RF signal having a nominal magnitude in excess of the minimum reception level.

Abstract translation: 提供超外差无线电接收机用于在接收频谱上接收RF信号。 无线电接收机包括具有用于根据驱动机构的移动定义无线电接收机的接收频率的驱动机构的信号寻找调谐器。 调谐器响应于启动信号以启动驱动机构的移动，以改变无线电接收机在接收频带上的接收频率。 此外，调谐器响应于停止信号，以在驱动机构在停止频率范围上惯性停止之后终止驱动机构的移动。 控制电路包括具有初级调谐电路和次谐波调谐电路的变压器，其各自呈现略微不同的谐振频率。 限幅器电路与控制电路相结合，为无线电接收机的IF信号提供频率响应曲线，该频率响应曲线相对于总体幅度被压缩并相对于峰值频率偏斜。 结果，仅当接收到的RF信号的标称幅度超过最小接收电平时，IF控制信号的幅度才超过触发电平，只有当无线电接收机的接收频率不同于 所接收的RF信号的量大致等于调谐器驱动机构的停止频率范围。 当IF信号的幅度超过触发电平时，停止信号被施加到调谐器，使得驱动机构以大致等于下一个接收到的RF信号的载波频率的频率大致等于具有超过 最小接收电平。