US3867589A
Expired / Lapsed
US
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Enhancing impedance characteristics of negative impedance repeaters operating at high gain
Assignee: ASTROCOM DIVISION OF Q C P Ltd
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Filing: 1973-09-04
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Granted: 1975-02-18
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Expires: 1993-09-04
Abstract
Abstract An alignment procedure for improving the high-gain impedance characteristics of a telephone repeater of the type employing both series-and shunt-connected negative impedance converters. Temporary terminating resistors are connected to each converter such that the repeater is operated at approximately 75-80 percent of its maximum gain with its transmission line terminals connected to a desired nominal image impedance. Using variable decade resistors and a return loss measuring set, small variations in the net terminating resistances of each of the two converters are made until return loss is maximized, thereby determining the values of permanent, fixed-value, impedanceoptimizing resistors which are then interconnected with and become a permanent part of the repeater''s strapping networks.
Inventors
- 👤 Peter G Junek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 10:59
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/36; H04B3/40
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
200 words
A process for aligning a telephone repeater of the type including both series-connected and shunt-connected negative impedance converters, each converter being provided with a strapping network of interconnectable resistors, said repeater being provided with line terminals for connecting said repeater in series with a two-wire transmission link having a predetermined nominal impedance, said process comprising, in combination, the steps of; connecting first and second temporary terminating resistance circuits to said series-connected and said shunt-connected converters respectively, each of said circuits having a fixed resistance component for setting the overall gain of said repeater at a predetermined level and a variable resistance component for altering the impedance characteristics of said repeater without substantially changing its gain; terminating said line terminals of said repeater with said predetermined nominal impedance; connecting a return loss measuring device to the repeater thus terminated; adjusting the value of said variable resistance component until the return loss as indicated by said measuring device is substantially maximized; and interconnecting in each of said strapping networks a permanent fixed resistor having a value substantially equal to the value of said variable component in the corresponding one of said temporary circuits at the time said measured return loss is maximized.
Claim 2
Dependent Claim
200 words
A process for aligning a telephone repeater of the type including both series-connected and shunt-connected negative impedance converters, each converter being provided with a strapping network of interconnectable resistors, said repeater being provided with line terminals for connecting said repeater in series with a two-wire transmission link having a predetermined nominal impedance, said process comprising, in combination, the steps of; connecting first and second temporary terminating resistance circuits to said series-connected and said shunt-connected converters respectively, each of said circuits having a fixed resistance component for setting the overall gain of said repeater at a predetermined level and a variable resistance component for altering the impedance characteristics of said repeater without substantially changing its gain; terminating said line terminals of said repeater with said predetermined nominal impedance; connecting a return loss measuring device to the repeater thus terminated; adjusting the value of said variable resistance component until the return loss as indicated by said measuring device is substantially maximized; and interconnecting in each of said strapping networks a permanent fixed resistor having a value substantially equal to the value of said variable component in the corresponding one of said temporary circuits at the time said measured return loss is maximized.
Claim 3
Dependent Claim
45 words
The process of claim 1 wherein said fixed resistance component of each of said temporary circuits is effective to set the gain of the connected converter at a nominal level approximately equal to 75 to 80 percent of the maximum gain capability of said converter.
Claim 4
Dependent Claim
60 words
The process of claim 2 further including the steps, following the maximization of said measured return loss, of measuring the overall gain of said repeater and readjusting said minor components to different settings providing maximum measured return loss if the measured gain of said repeater at the original settings departs from said nominal level by more than a predetermined amount.
Claim 5
Dependent Claim
175 words
A process for manufacturing a telephone repeater of the type comprising series-connected and shunt-connected negative impedance converters each terminated by a gain-controlling strapping network of interconnectable resistors, said repeater being provided with line terminals for serially connecting said repeater with a bi-directional two-wire telephone transmission link having a predetermined nominal image impedance, said process comprising, in combination, the steps of; terminating said line terminals with a temporary load of said predetermined nominal image impedance; terminating each of said converters with a temporary resistive circuit having a fixed major component for setting the gain of the connected converter at a predetermined level and having a variable minor component; varying said minor component in each of said temporary resistive circuits while measuring the return loss of said repeater until the measured return loss is maximized; and interconnecting in each of said strapping networks a permanent fixed resistor having a value substantially equal to the value of said variable component in the corresponding one of said temporary resistive circuits at the time said measured return loss is maximized.
Claim 6
Dependent Claim
175 words
A process for manufacturing a telephone repeater of the type comprising series-connected and shunt-connected negative impedance converters each terminated by a gain-controlling strapping network of interconnectable resistors, said repeater being provided with line terminals for serially connecting said repeater with a bi-directional two-wire telephone transmission link having a predetermined nominal image impedance, said process comprising, in combination, the steps of; terminating said line terminals with a temporary load of said predetermined nominal image impedance; terminating each of said converters with a temporary resistive circuit having a fixed major component for setting the gain of the connected converter at a predetermined level and having a variable minor component; varying said minor component in each of said temporary resistive circuits while measuring the return loss of said repeater until the measured return loss is maximized; and interconnecting in each of said strapping networks a permanent fixed resistor having a value substantially equal to the value of said variable component in the corresponding one of said temporary resistive circuits at the time said measured return loss is maximized.
Claim 7
Dependent Claim
45 words
The process of claim 4 wherein said fixed major component of each of said temporary networks is effective to set the gain of the connected converter at a nominal level approximately equal to 75 to 80 percent of the maximum gain capability of said converter.
Claim 8
Dependent Claim
56 words
The process of claim 5 further including the steps, following the maximization of said measured return loss, of measuring the overall gain of said repeater and readjusting said minor components to different settings providing maximum measured return loss if the measured gain of said repeater departs from said nominal level by more than a predetermined amount.
Claim 9
Dependent Claim
189 words
In a telephone repeater of the type comprising series-connected and shunt-connected negative impedance converters each terminated by a gain-controlling strapping network of interconnectable resistors, said repeater being provided with line terminals for serially connecting said repeater with a bidirectional two-wire telephone transmission link having a predetermined nominal image impedance, the improvement, comprising a permanent fixed resistor interconnected in each of said strapping networks, the value of said resistance being determined by the process comprising, in combination, the steps of; terminating said line terminals with a temporary load of said predetermined nominal image impedance; terminating each of said converters with a temporary resistive circuit having a fixed major component for setting the gain of the connected converter at a predetermined level and having a variable minor component; varying said minor component in each of said temporary resistive circuits while measuring the return loss of said repeater until the measured return loss is maximized; and setting the value of each of said permanent fixed resistors equal to the value of said variable component in the corresponding one of said temporary resistive circuits at the time said measured return loss is maximized.
Claim 10
Dependent Claim
189 words
In a telephone repeater of the type comprising series-connected and shunt-connected negative impedance converters each terminated by a gain-controlling strapping network of interconnectable resistors, said repeater being provided with line terminals for serially connecting said repeater with a bidirectional two-wire telephone transmission link having a predetermined nominal image impedance, the improvement, comprising a permanent fixed resistor interconnected in each of said strapping networks, the value of said resistance being determined by the process comprising, in combination, the steps of; terminating said line terminals with a temporary load of said predetermined nominal image impedance; terminating each of said converters with a temporary resistive circuit having a fixed major component for setting the gain of the connected converter at a predetermined level and having a variable minor component; varying said minor component in each of said temporary resistive circuits while measuring the return loss of said repeater until the measured return loss is maximized; and setting the value of each of said permanent fixed resistors equal to the value of said variable component in the corresponding one of said temporary resistive circuits at the time said measured return loss is maximized.
Claim 11
Dependent Claim
45 words
The improvement of claim 7 wherein said fixed major component of each of said temporary networks is effective to set the gain of the connected converter at a nominal level approximately equal to 75 to 80 percent of the maximum gain capability of said converter.
Claim 12
Dependent Claim
67 words
The improvement of claim 8 wherein the process of determining the value of said fixed resistors further includes the step following the maximization of said measured return loss, of measuring the overall gain of said repeater and readjusting said minor components to different settings providing maximum measured return loss if the measured gain of said repeater departs from said nominal level by more than a predetermined amount.
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) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |