US3818331A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Testing and measuring system for determining the characteristics of a network over a variable frequency range
Assignee: Siemens AG
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Filing: 1973-03-08
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Granted: 1974-06-18
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Expires: 1993-03-08
Abstract
Abstract A testing and measuring system for determining the attenuation characteristics of a network, wherein a pair of parallel paths are provided to which a variable frequency transmitter is connected and with the network or component to be tested mounted in one of the parallel branches. Modulators are mounted in each of the parallel branches so as to frequency shift the signals in the parallel branches to different frequencies, after which the parallel branches are connected together and pass through a frequency converter to provide an I. F. output at a test receiver. A variable gain control amplifier receives the output I. F. signals and a pair of band pass filters have their inputs connected to the output of the control amplifier and are tuned to respectively pass one of the side band frequencies of the modulator in the branch with the test object converted to the I. F. range, and one of the side band frequencies of the modulator in the parallel branch which did not include the test object converted to the I. F. range. A detector is connected to the output of the band pass filter which passes the signal which does not pass through the test object and supplies an input to a differential amplifier which receives a second input from a reference oscillator and the output of the differential amplifier is connected to the variable gain control of the control amplifier. This signal may also be supplied to the transmitter oscillator to control its amplitude level. The band pass filter which passes the signal that did not pass through the test object has an output which is supplied to a modulator which receives an injection frequency and which converts its frequency to the same as that of the band pass filter which passed the signal from the test object. The output of this modulator is supplied to the evaluation system for additionally determining the phase shift characteristics of the test object or its transmission properties including phase shift.
Inventors
- 👤 K Schlosser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:24
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/46; H04B3/48
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
242 words
A frequency-selective attenuation testing and measuring apparatus for use in wobble operation wherein a test oscillator feeds a variable frequency signal to a test object, and a test receiver which can be tuned and synchronized with the measuring frequency, and an evaluation means receiving the output of said test receiver and producing an attenuation versus frequency presentation comprising, an adder, a first modulator and said test object connected in series between said adder and the test oscillator, a second modulator connected between said adder and the test oscillator, the transmission properties of said first and second modulators being substantially the same, a pair of auxiliary alternating voltage sources supplying voltages (Uh1 and Uh2) to said first and second modulators of such frequencies that different frequency outputs are obtained, an intermediate frequency stage receiving the output of said adder, a first band pass filter connected to said intermediate frequency stage and passing one of the sideband frequencies of said first modulator in the I.F. range to said evaluation means, a second band pass filter connected to said intermediate frequency stage and passing one of the side band frequencies of said second modulator in the I. F. range, an amplitude comparing circuit receiving the output voltage of said second filter to compare it with the output of a reference voltage generator and a variable gain amplifier connected ahead of said first and second band pass filters and receiving an input from said comparing circuit.
Claim 2
Dependent Claim
242 words
A frequency-selective attenuation testing and measuring apparatus for use in wobble operation wherein a test oscillator feeds a variable frequency signal to a test object, and a test receiver which can be tuned and synchronized with the measuring frequency, and an evaluation means receiving the output of said test receiver and producing an attenuation versus frequency presentation comprising, an adder, a first modulator and said test object connected in series between said adder and the test oscillator, a second modulator connected between said adder and the test oscillator, the transmission properties of said first and second modulators being substantially the same, a pair of auxiliary alternating voltage sources supplying voltages (Uh1 and Uh2) to said first and second modulators of such frequencies that different frequency outputs are obtained, an intermediate frequency stage receiving the output of said adder, a first band pass filter connected to said intermediate frequency stage and passing one of the sideband frequencies of said first modulator in the I.F. range to said evaluation means, a second band pass filter connected to said intermediate frequency stage and passing one of the side band frequencies of said second modulator in the I. F. range, an amplitude comparing circuit receiving the output voltage of said second filter to compare it with the output of a reference voltage generator and a variable gain amplifier connected ahead of said first and second band pass filters and receiving an input from said comparing circuit.
Claim 3
Dependent Claim
107 words
A frequency-selective attenuation testing and measuring apparatus according to claim 1, wherein the output voltage of said second band pass filter is converted to the frequency of the output voltage of said first band pass filter by frequency converting means, said evaluation means receiving the output of said frequency converting means as a reference signal used jointly with the output voltage of said first band pass filter for obtaining transmission characteristics of said test object such as the vector diagram and its real and imaginary components as a function of frequency, and for determining the phase shift properties with a phase-measuring system, or serving for level-difference measurements.
Claim 4
Dependent Claim
58 words
A frequency-selective attenuation testing and measuring apparatus according to claim 1 wherein said pair of auxiliary alternating voltage sources comprises a joint auxiliary alternating voltage source oscillator, and a pair of frequency dividers which receive the output of said joint alternating voltage source oscillator, the outputs of said frequency dividers being connected to said first and second modulators.
Claim 5
Dependent Claim
28 words
A frequency-selective attenuation testing and measuring apparatus according to claim 2, wherein said frequency converting means receives an input derived from said pair of auxiliary alternating voltage sources.
Claim 6
Dependent Claim
29 words
A frequency-selective attenuation testing and measuring apparatus according to claim 1 wherein said variable gain amplifier influences the amplitude of said variable frequency signal supplied to said test objeCt.
Claim 7
Dependent Claim
57 words
A frequency-selective attenuation testing and measuring apparatus to claim 1 including a calibration oscillator connectible to said test receiver to calibrate it by adjusting the amplitude of the output of said reference voltage generator such that when a defined calibration voltage (Ue) is supplied by said calibration oscillator the output of said comparing circuit is as desired.
Claim 8
Dependent Claim
42 words
A frequency selective attenuation testing and measuring apparatus according to claim 1 wherein portions of said test transmitter and said test object are mounted in a separate plug-in unit and portions of said test receiver are mounted in a second plug-in unit.
Claim 9
Dependent Claim
199 words
A testing and measuring apparatus comprising a variable frequency test generator, a first modulator connected in series with a test object and the output of said test generator supplied thereto, a second modulator receiving an output of said test generator, auxiliary oscillator means connected to said first and second modulators and supplying different frequency inputs thereto, a frequency converter receiving the outputs of said first and second modulators and passing an I. F. frequency signal, a variable gain amplifier receiving the output of said frequency converter, a first band pass filter connected to the output of said variable gain amplifier and having a pass band to pass one of the sideband frequencies of said first modulator converted to the I.F. range, a second pass band filter connected to the output of said variable gain amplifier and having a pass band to pass one of the side band frequencies of said second modulator converted to the I. F. range, a reference voltage source, a voltage comparing circuit receiving an input from said reference voltage and from said second band pass filter to produce a control voltage, and said control voltage supplied to said variable gain amplifier to control its gain.
Claim 10
Dependent Claim
199 words
A testing and measuring apparatus comprising a variable frequency test generator, a first modulator connected in series with a test object and the output of said test generator supplied thereto, a second modulator receiving an output of said test generator, auxiliary oscillator means connected to said first and second modulators and supplying different frequency inputs thereto, a frequency converter receiving the outputs of said first and second modulators and passing an I. F. frequency signal, a variable gain amplifier receiving the output of said frequency converter, a first band pass filter connected to the output of said variable gain amplifier and having a pass band to pass one of the sideband frequencies of said first modulator converted to the I.F. range, a second pass band filter connected to the output of said variable gain amplifier and having a pass band to pass one of the side band frequencies of said second modulator converted to the I. F. range, a reference voltage source, a voltage comparing circuit receiving an input from said reference voltage and from said second band pass filter to produce a control voltage, and said control voltage supplied to said variable gain amplifier to control its gain.
Claim 11
Dependent Claim
187 words
A testing and measuring apparatus comprising, a variable gain and variable frequency test generator, a first modulator connected in series with a test object and the output of said test generator supplied thereto, a second modulator receiving an output of said test generator, auxiliary oscillator means connected to said first and second modulators and supplying different frequency inputs thereto, a frequency converter receiving the outputs of said first and second modulators and passing an I.F. frequency signal, a first band pass filter connected to an I. F. output terminal and having a pass band to pass one of the sideband frequencies of said first modulator, converted to the I. F. range, a second pass band filter connected to said I. F. output terminal and having a pass band to pass one of the sideband frequencies of said second modulator converted to the I. F. range, a reference voltage source, a voltage comparing circuit receiving an input from said reference voltage source and said second band pass filter to produce a control voltage, and said control voltage supplied to said variable gain test generator to control its gain.
Claim 12
Dependent Claim
187 words
A testing and measuring apparatus comprising, a variable gain and variable frequency test generator, a first modulator connected in series with a test object and the output of said test generator supplied thereto, a second modulator receiving an output of said test generator, auxiliary oscillator means connected to said first and second modulators and supplying different frequency inputs thereto, a frequency converter receiving the outputs of said first and second modulators and passing an I.F. frequency signal, a first band pass filter connected to an I. F. output terminal and having a pass band to pass one of the sideband frequencies of said first modulator, converted to the I. F. range, a second pass band filter connected to said I. F. output terminal and having a pass band to pass one of the sideband frequencies of said second modulator converted to the I. F. range, a reference voltage source, a voltage comparing circuit receiving an input from said reference voltage source and said second band pass filter to produce a control voltage, and said control voltage supplied to said variable gain test generator to control its gain.
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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) | 1977-06-17 | 1977-12-17 | 1978-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-17 | 1981-12-17 | 1982-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-17 | 1985-12-17 | 1986-06-18 | $7700.00 | Window Closed / Lapsed |