US3895191A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for measurement of channel separation in amplifier or the like
Assignee: TRIO ELECTRONICS Inc
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Filing: 1974-06-18
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Granted: 1975-07-15
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Expires: 1994-06-18
Abstract
Abstract Apparatus and method for measuring channel separation in a transmission circuit having at least first and second transmission channels, the apparatus comprising applying means for respectively applying to the first and second transmission channels first and second test signals of different frequency; first detecting means responsive to the first transmission channel for producing a first beat frequency signal, the amplitude of which is a function of the cross-talk from said second transmission channel to the first transmission channel and the frequency of which is the difference in frequency between the first and second test signals; and first measuring means responsive to the amplitude of the first beat frequency signal to obtain a measurement of the cross-talk from the second transmission channel to the first transmission channel.
Inventors
- 👤 Tadayoshi Koganezawa
- 👤 Ryoji Shiozawa
- 👤 Katsumi Takai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:21
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/44; H04H20/46; H04H20/47; H04H20/48; G; G01; G01R; G01R31/00; G01R31/28; G01R31/282; G01R31/2825; H04H40/00; H04H40/18; H04H40/27; H04H40/36; H04H40/45; H04H40/63
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
124 words
Apparatus for measuring channel separation in a transmission circuit having at least first and second transmission channels, said apparatus comprising: applying means for respectively applying to said first and second transmission channels first and second test signals of different frequency; first detecting means responsive to said first transmission channel for producing a first beat frequency signal, the amplitude of which is a function of the cross-talk from said second transmission channel to said first transmission channel and the frequency of which is the difference in frequency between said first and second test signals; and first measuring means responsive to the amplitude of said first beat frequency signal to obtain a measurement of said crosstalk from said second transmission channel to said first transmission channel.
Claim 2
Dependent Claim
124 words
Apparatus for measuring channel separation in a transmission circuit having at least first and second transmission channels, said apparatus comprising: applying means for respectively applying to said first and second transmission channels first and second test signals of different frequency; first detecting means responsive to said first transmission channel for producing a first beat frequency signal, the amplitude of which is a function of the cross-talk from said second transmission channel to said first transmission channel and the frequency of which is the difference in frequency between said first and second test signals; and first measuring means responsive to the amplitude of said first beat frequency signal to obtain a measurement of said crosstalk from said second transmission channel to said first transmission channel.
Claim 3
Dependent Claim
33 words
Apparatus as in claim 1 including a first band pass filter means responsive to said first detecting means for extracting said first beat frequency signal from the output of said first detecting means.
Claim 4
Dependent Claim
64 words
Apparatus as in claim 2 where the frequency of said first test signal is omega 1 and that of said second test signal is omega 2 and omega 1* omega 2 is sufficiently different from ( omega 1 + omega 2)/2 so that said first band pass filter means can extract said first beat frequency signal from said output of said first detecting means.
Claim 5
Dependent Claim
72 words
Apparatus as in claim 1 including second detecting means responsive to said second transmission channel for producing a first control signal corresponding to the average value of the signal in said second transmission channel and first automatic gain control amplifying means responsive to said first detecting means for amplifying said first beat frequency signal, the gain of said first automatic gain control amplifying means being a function of said first control signal.
Claim 6
Dependent Claim
39 words
Apparatus as in claim 4 including a reference control signal source and means for controlling the gain of said first automatic gain control amplifying means with the difference signal between said first control signal and said reference control signal.
Claim 7
Dependent Claim
53 words
Apparatus as in claim 4 including switch over means for connecting said first detecting means to the output of said second transmission channel and said second detecting means to the output of said first transmission channel so that the cross-talk from said first transmission channel to said second transmission channel can be measured.
Claim 8
Dependent Claim
154 words
Apparatus as in claim 4 where said second detecting means includes means for producing a second beat frequency signal, the amplitude of which is a function of the cross-talk from said first transmission channel to said second transmission channel and the frequency of which is the difference in frequency between said first and second test signals and where said first detecting means includes means for producing a second control signal corresponding to the average value of the signal in said first transmission channel, said apparatus including second automatic gain control amplifying means responsive to said second detecting means for amplifying said second beat frequency signal, the gain of said second automatic gain control amplifying means being a function of said second control signal; and second measuring means responsive to the amplitude of said second beat frequency signal to obtain a measurement of said cross-talk from said first transmission channel to said second transmission channel.
Claim 9
Dependent Claim
39 words
Apparatus as in claim 7 including a reference control signal source and means for controlling the gain of said second automatic gain control amplifying means with the difference signal between said second control signaL and said reference control signal.
Claim 10
Dependent Claim
33 words
Apparatus as in claim 7 including a second band pass filter means responsive to said second detecting means for extracting said second beat frequency signal from the output of said second detecting means.
Claim 11
Dependent Claim
36 words
Apparatus as in claim 1 where said transmission circuit is a stereo receiver and said applying means includes means for radiating said first and second test signals to said stereo receiver as a stereo test signal.
Claim 12
Independent Claim
62 words
A method for measuring channel separation in a transmission circuit having at least two transmission channels comprising the steps of: respectively applying at least two signals of different frequency to said two transmission channels and measuring the level of the beat frequency signal generated by interaction between the cross-talk component which is developed during transmission and one of said two applied signals.
Claim 13
Independent Claim
62 words
A method for measuring channel separation in a transmission circuit having at least two transmission channels comprising the steps of: respectively applying at least two signals of different frequency to said two transmission channels and measuring the level of the beat frequency signal generated by interaction between the cross-talk component which is developed during transmission and one of said two applied signals.
Claim 14
Dependent Claim
115 words
Method for measuring channel separation in a transmission circuit having at least first and second transmission channels, said method comprising the steps of; respectively applying to said first and second transmission channels first and second test signals of different frequency; producing, in response to said first transmission channel, a first beat frequency signal, the amplitude of which is a function of the cross-talk from said second transmission channel to said first transmission channel and the frequency of which is the difference in frequency between said first and second test signals; and measuring, in response to the amplitude of said first beat frequency signal, said cross-talk from said second transmission channel to said first transmission channel.
Claim 15
Dependent Claim
115 words
Method for measuring channel separation in a transmission circuit having at least first and second transmission channels, said method comprising the steps of; respectively applying to said first and second transmission channels first and second test signals of different frequency; producing, in response to said first transmission channel, a first beat frequency signal, the amplitude of which is a function of the cross-talk from said second transmission channel to said first transmission channel and the frequency of which is the difference in frequency between said first and second test signals; and measuring, in response to the amplitude of said first beat frequency signal, said cross-talk from said second transmission channel to said first transmission channel.
Claim 16
Dependent Claim
53 words
Method as in claim 12 including producing, in response to said second transmission channel, a first control signal corresponding to the average value of the signal in said second transmission channel and amplifying said first beat frequency signal and, controlling the amplification of said first beat frequency signal with said first control signal.
Claim 17
Dependent Claim
35 words
Method as in claim 12 including generating a reference control signal and controlling the amplification of said first beat frequency signal with the difference signal between said first control signal and said reference control signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-14 | 1979-01-13 | 1979-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-14 | 1983-01-13 | 1983-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-14 | 1987-01-13 | 1987-07-15 | $7700.00 | Window Closed / Lapsed |