US3825830A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Offset oscillator system for radio transmitter and receiver
Assignee: Motorola Solutions Inc
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Filing: 1972-12-06
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Granted: 1974-07-23
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Expires: 1992-12-06
Abstract
Abstract An oscillator system for determining the operating frequency of a transmitter and a receiver includes a receiver local oscillator and an oscillator-mixer combination for off-setting the frequency of the local oscillator to provide an excitation signal for the transmitter. The operating frequency of the transmitter and receiver can be changed by changing only the frequency of the local oscillator, thereby reducing the number of crystals or oscillators needed for a multifrequency radio. The offsetting oscillator is frequency modulated to frequency modulate the transmitter.
Inventors
- 👤 Connor W O
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:06
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/403; H04B1/405
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
381 words
In a radio transceiver system including a transmitter and a superheterodyne receiver having a mixer stage, a system for determining the frequency of operation of the transceiver including in combination: first oscillator means connected to said mixer stage for providing oscillations having a first predetermined frequency thereto for causing said mixer stage to produce a first beat frequency signal in response to said oscillatioNs; second oscillator means for providing oscillations having a second predetermined frequency, said second frequency being predeterminedly related to the frequency of said first beat frequency signal; mixer means connected to said first and second oscillator means for receiving said first and second frequency oscillations therefrom, said mixer means being further connected to said transmitter for providing a second beat frequency signal thereto in response to said first and second frequency oscillations for determining the operating frequency of said transmitter; means connected to said second oscillator means for modulating the frequency of said second frequency oscillations to thereby modulate the operating frequency of said transmitter; third oscillator means for providing oscillations having a third predetermined frequency, said third predetermined frequency being predeterminedly related to the frequency of said first beat frequency signal; second mixer means connected to said first and third oscillator means for receiving said first and third frequency oscillations therefrom, said second mixer means being further connected to said transmitter for providing a third beat frequency signal thereto in response to said first and third frequency oscillations for determining the operating frequency of said transmitter; means connected to said third oscillator means for modulating the frequency of said third frequency oscillations to thereby modulate the operating frequency of said transmitter; switch means connected to said second and third oscillator means for selectively rendering one of said second and third oscillator means operative; a diode matrix including a plurality of diodes connected to said first oscillator means for changing the frequency of operation of said first oscillator means, and to said switch means for determining the one of said second and third oscillator means rendered operative thereby; and selector switch means connected to said matrix for causing said matrix to operate said first oscillator means at a predetermined frequency and for causing said switch means to render a predetermined one of said second and third oscillators operative.
Claim 2
Dependent Claim
381 words
In a radio transceiver system including a transmitter and a superheterodyne receiver having a mixer stage, a system for determining the frequency of operation of the transceiver including in combination: first oscillator means connected to said mixer stage for providing oscillations having a first predetermined frequency thereto for causing said mixer stage to produce a first beat frequency signal in response to said oscillatioNs; second oscillator means for providing oscillations having a second predetermined frequency, said second frequency being predeterminedly related to the frequency of said first beat frequency signal; mixer means connected to said first and second oscillator means for receiving said first and second frequency oscillations therefrom, said mixer means being further connected to said transmitter for providing a second beat frequency signal thereto in response to said first and second frequency oscillations for determining the operating frequency of said transmitter; means connected to said second oscillator means for modulating the frequency of said second frequency oscillations to thereby modulate the operating frequency of said transmitter; third oscillator means for providing oscillations having a third predetermined frequency, said third predetermined frequency being predeterminedly related to the frequency of said first beat frequency signal; second mixer means connected to said first and third oscillator means for receiving said first and third frequency oscillations therefrom, said second mixer means being further connected to said transmitter for providing a third beat frequency signal thereto in response to said first and third frequency oscillations for determining the operating frequency of said transmitter; means connected to said third oscillator means for modulating the frequency of said third frequency oscillations to thereby modulate the operating frequency of said transmitter; switch means connected to said second and third oscillator means for selectively rendering one of said second and third oscillator means operative; a diode matrix including a plurality of diodes connected to said first oscillator means for changing the frequency of operation of said first oscillator means, and to said switch means for determining the one of said second and third oscillator means rendered operative thereby; and selector switch means connected to said matrix for causing said matrix to operate said first oscillator means at a predetermined frequency and for causing said switch means to render a predetermined one of said second and third oscillators operative.
Claim 3
Dependent Claim
35 words
A system as recited in claim 1 wherein said first oscillator means includes a plurality of frequency determining oscillators, each frequency determining oscillator being connected to at least one diode of said plurality of diodes.
Claim 4
Dependent Claim
25 words
A system as recited in claim 2 wherein said selector switch means is further connected to at least one diode of said plurality of diodes.
Claim 5
Dependent Claim
31 words
A system as recited in claim 3 further including jumper means for selectively connecting predetermined ones of said diodes to predetermined ones of said frequency determining oscillators and said switch means.
Claim 6
Dependent Claim
28 words
A system as recited in claim 4 wherein said second and third oscillator means have different frequencies of oscillation, the difference in said oscillation frequencies being 5 MHz.
Claim 7
Dependent Claim
28 words
A system as recited in claim 4 wherein said second and third oscillator means have different frequencies of oscillation, the difference in said oscillation frequencies being 3 MHz.
Claim 8
Dependent Claim
22 words
A system as recited in claim 3 wherein said selector switch means includes a selector switch connected to each of said diodes.
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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) | 1977-07-22 | 1978-01-21 | 1978-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-22 | 1982-01-21 | 1982-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-22 | 1986-01-21 | 1986-07-23 | $7700.00 | Window Closed / Lapsed |