Circuit for controlling operator indicators in an AM stereo rece

Details Circuit for controlling operator indicators in an AM stereo rece Circuit for controlling operator indicators in an AM stereo rece

1987-08-21

1990-07-24

Isen, Forester W.

Electrical audio signal processing systems and devices

Binaural and stereophonic

Broadcast or multiplex stereo

381 12, 455154, H04H 500

Patent

active

049440110

ABSTRACT:
Disclosed is a circuit for controlling the activation of a stereo indicator and a tune indicator in an AM stereo receiver. In the preferred embodiment, a pilot tone detector is employed to determine if the input signal is a stereo signal and an AGC is used to detect a preselected improvement in the amplitude of the received signal. A capacitor is charged in response to the stereo or the amplitude condition. When the charge level of the capacitor reaches a first predetermined level, a tune indicator driver is enable to allow a tune detect circuit to drive the indicator. This prevents the tune indication from activating before the receiver is stabilized. When the charge level of the capacitor reaches a second predetermined level, a stereo indicator driver gradually activates the stereo indicator. This prevents sudden power drains from adversely affecting the circuit.

REFERENCES:
patent: 3416032 (1966-03-01), Jahns et al.
patent: 3717817 (1973-02-01), Auerbach
patent: 4218586 (1980-08-01), Parker et al.
patent: 4236041 (1980-11-01), Thomas
patent: 4405837 (1983-09-01), Ecklund
patent: 4409436 (1983-10-01), Numata et al.
patent: 4503397 (1985-03-01), Schultz
patent: 4602379 (1986-07-01), Ecklund
patent: 4688254 (1987-08-01), Ecklund
patent: 4694501 (1987-09-01), Cheng
patent: 4747141 (1988-05-01), Kahn
LB8-1 (National Semiconductor, 1969).
AN 20-8,9 (National Semiconductor), 1969.

Affiliated with

Also associated with

Rating

Circuit for controlling operator indicators in an AM stereo rece does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Circuit for controlling operator indicators in an AM stereo rece, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Circuit for controlling operator indicators in an AM stereo rece will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1272022