Patent US3769604A successfully refreshed from Google Patents.
US3769604A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switched and summed filter arrangement
Assignee: GEN AVIAT ELECTRONICS Inc
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Filing: 1971-03-12
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Granted: 1973-10-30
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Expires: 1991-03-12
Abstract
Abstract A transmitter circuit for use in a multi-frequency transmitter which uses a two input diplexer to combine the outputs of separate bandpass filters tuned to adjacent bands. A mixer is connected to one or the other of the filters depending upon the band in which the desired frequency occurs. The connection of the mixer to the filters is accomplished by transistor amplifiers which can be biased off to disconnect.
Inventors
- 👤 N Atkinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:02
CPC Classifications
H; H03; H03H; H03H11/00; H03H11/02; H03H11/04; H03H11/12; H03H11/1213; H03F; H03F3/00; H03F3/68; H03F3/72
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
92 words
A circuit for producing a plurality of different frequencies which comprises: a. means providing a single source of frequencies, b. a plurality of bandpass filters, each having an input and an output and each being tuned to a different band, c. switching means for coupling said source to any one of said inputs of said plurality of bandpass filters, d. a multiplexer means having an output and a plurality of inputs, each input of the multiplexer means being connected to an output of a respective one of said plurality of bandpass filters.
Claim 2
Dependent Claim
92 words
A circuit for producing a plurality of different frequencies which comprises: a. means providing a single source of frequencies, b. a plurality of bandpass filters, each having an input and an output and each being tuned to a different band, c. switching means for coupling said source to any one of said inputs of said plurality of bandpass filters, d. a multiplexer means having an output and a plurality of inputs, each input of the multiplexer means being connected to an output of a respective one of said plurality of bandpass filters.
Claim 3
Dependent Claim
17 words
The circuit of claim 1 in which two of the bandpass filters are tuned to adjacent bands.
Claim 4
Dependent Claim
18 words
The circuit of claim 2 in which there are only two bandpass filters and two multiplexer means inputs.
Claim 5
Dependent Claim
96 words
The circuit arrangement of claim 3 wherein said multiplexer is a diplexer which comprises a first capacitance, a resistance and an inductance each of which has a first end and a second end; said first ends of said resistance, capacitance and inductance being connected together and defining one of said diplexer inputs; said second ends of said resistance, capacitance and inductance being connected together and defining the other of said diplexer inputs; said inductor having a center tap which defines the output of said diplexer; and a second capacitance connected between said diplexer output and ground.
Claim 6
Dependent Claim
17 words
The circuit of claim 4 in which said bandpass filters each have a plurality of resonant circuits.
Claim 7
Dependent Claim
22 words
The circuit of claim 10 in which said means providing a single source of frequencies provides a single source of radio frequencies.
Claim 8
Dependent Claim
24 words
The circuit of claim 1 in which the switching means includes one semiconductor device associated with each one of said plurality of bandpass filters.
Claim 9
Dependent Claim
12 words
The circuit of claim 7 in which said semiconductor devices are transistors.
Claim 10
Dependent Claim
29 words
The circuit of claim 8 in which said source is coupled to the input of one of said bandpass filters only when its associated transistor is biased to amplify.
Claim 11
Dependent Claim
17 words
The circuit of claim 1 in which the source of frequencies is the output of a mixer.
Claim 12
Dependent Claim
17 words
The circuit of claim 1 in which said bandpass filters each have a plurality of resonant circuits.
Claim 13
Dependent Claim
22 words
The circuit of claim 1 in which said means providing a single source of frequencies provides a single source of radio frequencies.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |