US3732498A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fine-tuning and stereo indicator system
Assignee: Zenith Electronics LLC
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Filing: 1971-10-12
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Granted: 1973-05-08
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Expires: 1991-10-12
Abstract
Abstract A fine-tuning and stereo indicator system for an AM-FM radio receiver capable of receiving FM stereo broadcast signals. The indicator system utilizes two lamps integrally mounted within a dial pointer carriage assembly to illuminate a dial pointer exhibiting light-conductive properties. Whenever a monophonic radio signal is received, the dial pointer glows with a variable intensity representative of the received signal-strength, i.e., fine-tuning. Upon receiving a stereophonic broadcast signal, the fine-tuning lamp is extinguished, and the stereo indicator lamp is fully illuminated and subsequently filtered to impart a second distinctive color (e.g., red) to the dial pointer indicative of stereo reception.
Inventors
- 👤 O Beckman
- 👤 W Klymkiw
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:32
CPC Classifications
H; H03; H03J; H03J3/00; H03J3/02; H03J3/12; H03J3/14; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/1646
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
160 words
In a radio receiver capable of receiving stereo broadcast signals and including a dial scale, a fine-tuning and stereo indicator system comprising in combination: fine-tuning indicator means including a first lamp for generating a variable intensity light representative of the signal strength of a received broadcast signal; stereo indicator means for extinguishing said first lamp, said stereo indicator means including a second lamp and a light filter for generating a distinctively colored light during reception of a stereo broadcast signal; a carriage assembly movable with respect to said dial scale in accordance with the tuning of said receiver, said first lamp and said second lamp being mounted on said carriage assembly; and a light-conductive pointer mounted on said carriage assembly adjacent said dial scale and being coupled to said first lamp and said second lamp, said pointer glowing with increased intensity as the desired broadcast frequency is fine-tuned and exhibiting a color change when a stereo broadcast signal is received.
Claim 2
Dependent Claim
160 words
In a radio receiver capable of receiving stereo broadcast signals and including a dial scale, a fine-tuning and stereo indicator system comprising in combination: fine-tuning indicator means including a first lamp for generating a variable intensity light representative of the signal strength of a received broadcast signal; stereo indicator means for extinguishing said first lamp, said stereo indicator means including a second lamp and a light filter for generating a distinctively colored light during reception of a stereo broadcast signal; a carriage assembly movable with respect to said dial scale in accordance with the tuning of said receiver, said first lamp and said second lamp being mounted on said carriage assembly; and a light-conductive pointer mounted on said carriage assembly adjacent said dial scale and being coupled to said first lamp and said second lamp, said pointer glowing with increased intensity as the desired broadcast frequency is fine-tuned and exhibiting a color change when a stereo broadcast signal is received.
Claim 3
Dependent Claim
51 words
A radio receiver in accordance with claim 1 wherein said carriage assembly has two preformed cylindrical cavities for mounting said first lamp and said second lamp therein and wherein said light conductive pointer is ''''f''''-shaped with the arms of said ''''f'''' in light conducting relationship with respective ones of said lamps.
Claim 4
Dependent Claim
74 words
A radio receiver in accordance with claim 2, wherein said fine-tuning indicator means includes a first transistor having said first and said second lamps in its collector load circuit; said stereo indicator means including a second transistor having said second lamp in its collector load circuit; and wherein said second lamp has at least twice the current rating of said first lamp whereby during conduction of said second transistor, said first lamp is extinguished.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-07 | 1976-11-06 | 1977-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-07 | 1980-11-06 | 1981-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-07 | 1984-11-06 | 1985-05-08 | $7700.00 | Window Closed / Lapsed |