Line conditioner with independent gain and delay control

Claim 2

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characteristic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein each of said delay circuits includes: a delay circuit input terminal; a first active gyrator simulating an inductive impedance and connected in series with said delay circuit input terminal; a capacitor connected in parallel across said gyrator; and said delay adjustment means in the form of an adjustable resistance connected between ground and the end of said capacitor remote from said delay circuit input terminal.

Claim 3

The system according to claim 1 wherein said active gyrator comprises: first and second operational amplifiers, each having an output terminal and inverting and non-inverting input terminals, wherein said capacitor is connected between the delay circuit input terminal and the non-inverting input terminal of said first operational amplifier; a first resistive impedance connected in series between the delay circuit input terminal and the inverting input terminal of said first operational amplifier; a second resistive impedance connected in negative feedback relation between the output terminal of said first operational amplifier and the inverting input terminal of that amplifier; a third resistive impedance connected in series between the output terminal of said first operational amplifier and the inverting input terminal of said second operational amplifier; a fourth capacitive impedance connected in negative feedback relation between the output and inverting input terminals of said second operational amplifier; and a fifth resistive impedance connected between the output terminal of said second operational amplifier and the non-inverting input terminal of said first operational amplifier; wherein said delay circuit has an output terminal which corresponds to the output terminal of said first operational amplifier.

Claim 4

The system according to claim 2 wherein said first and second resistive impedances are equal.

Claim 5

The system according to claim 3 wherein said first resistive impedance is the same in each of said delay circuits, said second resistive impedance is the same in each of said delay circuits, and said fourth capacitive impedance is the same in each of said delay circuits, and said third and fifth resistive impedances are different in each delay circuit and depend upon the frequency to which the delay circuit is tuned.

Claim 6

The system according to claim 2 wherein each of said amplitude circuits comprises: an amplitude circuit input terminal; an amplitude circuit output terminal; a third operational amplifier having an inverting input terminal and an output terminal; a second active gyrator having input and output terminals and an inductive impedance; a second capacitor; said amplitude adjustment means in the form of a second adjustable resistance; means connecting said second adjustable resistance, said second capacitor and said second gyrator in parallel combination between a common junction and ground; a series resistor connected between said amplitude circuit input terminal and said common junction; means connecting the output terminal of said second gyrator to said non-inverting input terminal of said third operational amPlifier; an input resistor connected between said amplitude circuit input terminal and said inverting input terminal of said third operational amplifier; and a feedback resistor connected between the output and inverting input terminals of said third operational amplifier.

Claim 7

The system according to claim 5 wherein said input and feedback resistors are of equal resistance.

Claim 8

The system according to claim 5 wherein all of said delay adjustment means and all of said amplitude adjustment means are part of a common module which is readily detachable from said system, said delay and amplitude adjustment means each including a manually adjustable member which is accessible at the front panel of said system when said module is attached to said system.

Claim 9

The system according to claim 7 wherein said input amplifier means includes gain adjustment means in the form of a potentiometer with a resistance which is substantially linearly related to the gain of said input amplifier means, wherein said potentiometer is part of said common module.

Claim 10

The system according to claim 8 wherein said input amplifier means comprises: an input amplifier input terminal; an input amplifier output terminal; a fourth operational amplifier having inverting and non-inverting input terminals and an output terminal; a sixth resistive impedance connected between said input amplifier input terminal and the inverting input terminal of said fourth operational amplifier; a seventh resistive impedance connected in negative feedback relation between said output and inverting input terminals of said fourth operational amplifier; an eighth resistive impedance connected in series between said input amplifier input terminal and the non-inverting input terminal of said fourth operational amplifier; and said potentiometer connected between the non-inverting input terminal of said fourth operational amplifier and ground.

Claim 11

The system according to claim 9 wherein said input amplifier means further comprises: a fifth operational amplifier having inverting and non-inverting input terminals and an output terminal; means connecting the output terminal of said fourth operational amplifier to the non-inverting input terminal of said fifth operational amplifier; a ninth resistive impedance connected between the output terminal of said fifth operational amplifier and said input amplifier output terminal; a 10th resistive impedance connected between the input amplifier output terminal and the inverting input terminal of said fifth operational amplifier; an 11th resistive impedance connected between ground and the inverting input terminal of said fifth operational amplifier; and a 12th resistive impedance and an open-close switch means connected in series between ground and said inverting input terminal of said fifth operational amplifier, said switch means serving as a coarse gain control for said input amplifier means, said switch means being part of said common module.

Claim 12

The system according to claim 10 wherein said output amplifier means comprises: an output amplifier input terminal; an output transformer having primary and secondary windings; a sixth operational amplifier having an inverting input terminal and an output terminal; 13th and 14th resistive impedances connected in series between said output amplifier input terminal and the inverting input terminal of said sixth operational amplifier; a negative voltage feedback path including a 15th resistive impedance connected between the output and inverting input terminals of said sixth operational amplifier; and a negative current feedback path comprising the primary winding of said transformer connected between the output terminal of said sixth operational amplifier and the junction between said 13th and 14th resistive impedance.

Claim 13

The system according to claim 8 wherein said output aMplifier means comprises: an output amplifier input terminal; an output transformer having primary and secondary windings; a fourth operational amplifier having an inverting input terminal and an output terminal; sixth and seventh resistive impedances connected in series between said output amplifier input terminal and the inverting input terminal of said fourth operational amplifier; a negative voltage feedback path including an eighth resistive impedance connected between the output and inverting input terminals of said fourth operational amplifier; and a negative current feedback path comprising the primary winding of said transformer connected between the output terminal of said fourth operational amplifier and the junction between said sixth and seventh resistive impedances; wherein said sixth resistive impedance is very much smaller than said seventh resistive impedance, and wherein said eighth resistive impedance is approximately twice as large as said seventh resistive impedance.

Claim 14

The system according to claim 5 wherein said input amplifier means includes gain adjustment means in the form of a potentiometer with a resistance which is substantially linearly related to the gain of said input amplifier means.

Claim 15

The system according to claim 5 wherein said second active gyrator comprises: fourth and fifth operational amplifiers, each having an output terminal and inverting and non-inverting input terminals, wherein said second capacitor is connected between ground and the non-inverting input terminal of said fourth operational amplifier; a sixth resistive impedance connected between ground and the inverting input terminal of said fourth operational amplifier; a seventh resistive impedance connected in negative feedback relation between the output terminal of said fourth operational amplifier and the inverting input terminal of that amplifier; an eighth resistive impedance connected in series between the output terminal of said fourth operational amplifier and the inverting input terminal of said fifth operational amplifier; a ninth capacitive impedance connected in negative feedback relation between the output and inverting input terminals of said fifth operational amplifier; and a 10th resistive impedance connected between the output terminal of said fifth operational amplifier and the non-inverting input terminal of said fourth operational amplifier.

Claim 16

The system according to claim 2 wherein all of said delay adjustment means and all of said amplitude adjustment means are part of a common module which is readily detachable from said system, said delay and amplitude adjustment means each including a manually adjustable member which is accessible at the front panel of said system when said module is attached to said system.

Claim 17

The system according to claim 2 wherein said input amplifier means includes gain adjustment means in the form of a potentiometer with a resistance which is substantially linearly related to the gain of said input amplifier means, wherein said potentiometer is part of said common module.

Claim 18

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characterisTic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein each of said amplitude circuits comprises: an amplitude circuit input terminal; an amplitude circuit output terminal; a first operational amplifier having an inverting input terminal and an output terminal; an active gyrator having input and output terminals and an inductive impedance; a capacitor; said amplitude adjustment means in the form of an adjustable resistance; means connecting said adjustable resistance, said capacitor and said gyrator in parallel combination between a common junction and ground; a series resistor connected between said amplitude circuit input terminal and said common junction; means connecting the output terminal of said gyrator to said non-inverting input terminal of said first operational amplifier; an imput resistor connected between said amplitude circuit input terminal and said inverting input terminal of said first operational amplifier; and a feedback resistor connected between the output and inverting input terminals of said first operational amplifier.

Claim 19

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characterisTic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein each of said amplitude circuits comprises: an amplitude circuit input terminal; an amplitude circuit output terminal; a first operational amplifier having an inverting input terminal and an output terminal; an active gyrator having input and output terminals and an inductive impedance; a capacitor; said amplitude adjustment means in the form of an adjustable resistance; means connecting said adjustable resistance, said capacitor and said gyrator in parallel combination between a common junction and ground; a series resistor connected between said amplitude circuit input terminal and said common junction; means connecting the output terminal of said gyrator to said non-inverting input terminal of said first operational amplifier; an imput resistor connected between said amplitude circuit input terminal and said inverting input terminal of said first operational amplifier; and a feedback resistor connected between the output and inverting input terminals of said first operational amplifier.

Claim 20

The system according to claim 17 wherein said input and feedback resistors are of equal resistance.

Claim 21

The system according to claim 18 wherein all of said delay adjustment means and all of said amplitude adjustment means are part of a common module which is readily detachable from said system, said delay and amplitude adjustment means each including a manually adjustable member which is accessible at the front panel of said system when said module is attached to said system.

Claim 22

The system according to claim 18 wherein said active gyrator comprises: second and third operational amplifiers, each having an output terminal and inverting and non-inverting input terminals, wherein said capacitor is connected between ground and the non-inverting input terminal of said second operational amplifier; a first resistive impedance connected in series between ground and the inverting input terminal of said second operational amplifier; a second resistive impedance connected in negative feedback relation between the output terminal of said second operational amplifier and the inverting input terminal of that amplifier; a third resistive impedance connected in series between the output terminal of said second operational amplifier and the inverting input terminal of said third operational amplifier; a fourth capacitive impedance connected in negative feedback relation between the output and inverting input terminals of said third operational amplifier; and a fifth resistive impedance connected between the output terminal of said third operational amplifier and the non-inverting input terminal of said second operational amplifier.

Claim 23

The system according to claim 20 wherein said input amplifier means comprises: an input amplifier input terminal; an input amplifier output terminal; a fourth operational amplifier having inverting and non-inverting input terminals and an output terminal; a sixth resistive impedance connected between said input amplifier input terminal and the inverting input terminal of said fourth operational amplifier; a seventh resIstive impedance connected in negative feedback relation between said output and inverting input terminals of said fourth operational amplifier; an eighth resistive impedance connected in series between said input amplifier input terminal and the non-inverting input terminal of said fourth operational amplifier; and said potentiometer connected between the non-inverting input terminal of said fourth operational amplifier and ground.

Claim 24

The system according to claim 20 wherein said output amplifier means comprises: an output amplifier input terminal; an output transformer having primary and secondary windings; a fifth operational amplifier having an inverting input terminal and an output terminal; ninth and tenth resistive impedances connected in series between said output amplifier input terminal and the inverting input terminal of said fifth operational amplifier; a negative voltage feedback path including an eleventh resistive impedance connected between the output and inverting input terminals of said fifth operational amplifier; and a negative current feedback path comprising the primary winding of said transformer connected between the output terminal of said fifth operational amplifier and the junction between said ninth and tenth resistive impedances; wherein said ninth resistive impedance is very much smaller than said 10th resistive impedance, and wherein said 11th resistive impedance is approximately twice as large as said 10th resistive impedance.

Claim 25

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characteristic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein said input amplifier means includes gain adjustment means in the form of a potentiometer with a resistance which is substantially linearly related to the gain of said input amplifier means and wherein said input amplifier means comprises: an input amplifier input terminal; an input amplifier output terminal; a first operational amplifier having inverting and non-inverting input terminals and an output terminal; a resistive impedance connected between said input amplifier input terminal and the inverting input terminal of said operational amplifier; a resistive impedance connected in negative feedback relation between said output and inverting input terminals of said operational amplifier; a resistive impedance connected in series between said input amplifier input terminal and the non-inverting input terminal of said operational amplifier; and said potentiometer connected between the non-inverting input terminal of said first operational amplifier and ground.

Claim 26

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characteristic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein said input amplifier means includes gain adjustment means in the form of a potentiometer with a resistance which is substantially linearly related to the gain of said input amplifier means and wherein said input amplifier means comprises: an input amplifier input terminal; an input amplifier output terminal; a first operational amplifier having inverting and non-inverting input terminals and an output terminal; a resistive impedance connected between said input amplifier input terminal and the inverting input terminal of said operational amplifier; a resistive impedance connected in negative feedback relation between said output and inverting input terminals of said operational amplifier; a resistive impedance connected in series between said input amplifier input terminal and the non-inverting input terminal of said operational amplifier; and said potentiometer connected between the non-inverting input terminal of said first operational amplifier and ground.

Claim 27

The system according to claim 23 wherein said input amplifier means further comprises: a second operational amplifier having inverting and non-inverting input terminals and an output terminal; means connecting the output terminal of said first operational amplifier to the non-inverting input terminal of said second operational amplifier; a fifth resistive impedance connected between the output terminal of said second operational amplifier and said input amplifier output terminal; a sixth resistive impedance connected between the input amplifier output terminal and the inverting input terminal of said second operational amplifier; a seventh resistive impedance connected in between ground and the inverting input terminal of said second operational amplifier; and an eighth resistive impedance and an open-close switch means connected in series between ground and said inverting input terminal of said second operational amplifier, said switch means serving as a coarse gain control for said input amplifier means.

Claim 28

The system according to claim 24 wherein all of said delay adjustment means and all of said amplitude adjustment means are part of a common module which is readily detachable from said system, said delay and amplitude adjustment means each including a manually adjustable member which is accessible at the front panel of said system when said module is attached to said system.

Claim 29

The system according to claim 23 wherein said output amplifier means comprises: an output amplifier input terminal; an output transformer having primary and secondary windings; a second operational amplifier having an inverting input terminal and an output terminal; fifth and sixth resistive impedances connected in series between said output amplifier input terminal and the inverting input terminal of said second operational amplifier; a negative voltage feedback path including a seventh resistive impedance connected between the output and inverting input terminals of said second operational amplifier; and a negative current feedback path comprising the primary winding of said transformer connected between the output terminal of said second operational amplifier and the junction between said fifth and sixth resistive impedances; wherein said fifth resistive impedance is very much smaller than said sixth resistive impedance, and wherein said seventh resistive impedance is approximately twice as large as said sixth resistive impedance.

Claim 30

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characteristic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustmenT means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein said output amplifier means comprises: an output amplifier input terminal; an output transformer having primary and secondary windings; an operational amplifier having an inverting input terminal and an output terminal; first and second resistive impedances connected in series between said output amplifier input terminal and the inverting input terminal of said operational amplifier; a negative voltage feedback path including a third resistive impedance connected between the output and inverting input terminals of said operational amplifier; and a negative current feedback path comprising the primary winding of said transformer connected between the output terminal of said operational amplifier and the junction between said first and second resistive impedances; wherein said first resistive impedance is very much smaller than said second resistive impedance, and wherein said third resistive impedance is approximately twice as large as said second resistive impedance.

Claim 31

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characteristic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustmenT means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein said output amplifier means comprises: an output amplifier input terminal; an output transformer having primary and secondary windings; an operational amplifier having an inverting input terminal and an output terminal; first and second resistive impedances connected in series between said output amplifier input terminal and the inverting input terminal of said operational amplifier; a negative voltage feedback path including a third resistive impedance connected between the output and inverting input terminals of said operational amplifier; and a negative current feedback path comprising the primary winding of said transformer connected between the output terminal of said operational amplifier and the junction between said first and second resistive impedances; wherein said first resistive impedance is very much smaller than said second resistive impedance, and wherein said third resistive impedance is approximately twice as large as said second resistive impedance.

Claim 32

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characteristic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein all of said delay adjustment means and all of said amplitude adjustment means are part of a common module which is readily detachable from said system, said delay and amplitude adjustment means each including a manually adjustable member which is accessible at the front panel of said system when said module is attached to said system.

Claim 33

A line conditioner system providing adjustable compensation for frequency-dependent distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: broadband input amplifier means arranged to receive signals from said transmission line, said broadband amplifier having an adjustable gain for all signal frequencies in said prescribed frequency range; a plurality of cascaded delay circuits connected in cascade with said broadband amplifier means, each delay circuit being tuned to a different frequency within said prescribed frequency range and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit having a constant gain versus frequency characteristic; a plurality of cascaded amplitude circuits connected in cascade with said delay circuits, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; and output amplifier means connected in cascade with said delay and amplitude circuits for providing an output signal from said system and providing a system output impedance which is matched to a predetermined impedance; wherein all of said delay adjustment means and all of said amplitude adjustment means are part of a common module which is readily detachable from said system, said delay and amplitude adjustment means each including a manually adjustable member which is accessible at the front panel of said system when said module is attached to said system.

Claim 34

A line conditioner system providing adjustable compensation for frequency-dependent delay distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: input means arranged to receive signals from said transmission line; and a plurality of cascaded delay circuits connected in cascade with said input means, each delay circuit being tuned to a different frequency within said prescribed frequency rAnge and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit being characterized by: a delay circuit input terminal; an active gyrator simulating an inductive impedance and connected in series with said delay circuit input terminal; a capacitor connected in parallel across said gyrator; and said delay adjustment means in the form of an adjustable resistance connected between ground and the end of said capacitor remote from said delay circuit input terminal.

Claim 35

A line conditioner system providing adjustable compensation for frequency-dependent delay distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: input means arranged to receive signals from said transmission line; and a plurality of cascaded delay circuits connected in cascade with said input means, each delay circuit being tuned to a different frequency within said prescribed frequency rAnge and including delay adjustment means for adjusting signal delay therethrough in a relatively small range of frequencies centered at said tuned frequency, each delay circuit being characterized by: a delay circuit input terminal; an active gyrator simulating an inductive impedance and connected in series with said delay circuit input terminal; a capacitor connected in parallel across said gyrator; and said delay adjustment means in the form of an adjustable resistance connected between ground and the end of said capacitor remote from said delay circuit input terminal.

Claim 36

The system according to claim 29 wherein said active gyrator comprises: first and second operational amplifiers, each having an output terminal and inverting and non-inverting input terminals, wherein said capacitor is connected between the delay circuit input terminal and the non-inverting input terminal of said first operational amplifier; a first resistive impedance connected in series between the delay circuit input terminal and the inverting input terminal of said first operational amplifier; a second resistive impedance connected in negative feedback relation between the output terminal of said first operational amplifier and the inverting input terminal of that amplifier; a third resistive impedance connected in series between the output terminal of said first operational amplifier and the inverting input terminal of said second operational amplifier; a fourth capacitive impedance connected in negative feedback relation between the output and inverting input terminals of said second operational amplifier; and a fifth resistive impedance connected between the output terminal of said second operational amplifier and the non-inverting input terminal of said first operational amplifier; wherein said delay circuit has an output terminal which corresponds to the output terminal of said first operational amplifier.

Claim 37

The system according to claim 30 wherein said first and second resistive impedances are equal.

Claim 38

The system according to claim 31 wherein said first resistive impedance is the same in each of said delay circuits, said second resistive impedance is the same in each of said delay circuits, and said fourth capacitive impedance is the same in each of said delay circuits, and said third and fifth resistive impedances are different in each delay circuit and depend upon the frequency to which the delay circuit is tuned.

Claim 39

A line conditioner system providing adjustable compensation for frequency-dependent amplitude distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: input means arranged to receive signals from said transmission line; and a plurality of cascaded amplitude circuits connected in cascade with said input means, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; wherein each of said amplitude circuits comprises: an amplitude circuit input terminal; an amplitude circuit output terminal; a first operational amplifier having an inverting input terminal and an output terminal; an active gyrator having input and output terminals and an inductive impedance; a capacitor; said amplitude adjustment means in the form of an adjustable resistance; means connecting said adjustable resistance, said capacitor and said gyrator in parallel combination between a common junction and ground; a series resistor connected betweEn said amplitude circuit input terminal and said common junction; means connecting the output terminal of said gyrator to said non-inverting input terminal of said first operational amplifier; an input resistor connected between said amplitude circuit input terminal and said inverting input terminal of said first operational amplifier; and a feedback resistor connected between the output and inverting input terminals of said first operational amplifier.

Claim 40

A line conditioner system providing adjustable compensation for frequency-dependent amplitude distortion introduced by a transmission line onto signals within a prescribed frequency range which are transmitted along the transmission line, said system comprising: input means arranged to receive signals from said transmission line; and a plurality of cascaded amplitude circuits connected in cascade with said input means, each amplitude circuit being tuned to a different mid-band frequency within said prescribed frequency range and including amplitude adjustment means for adjusting circuit gain in a relatively small range of frequencies centered at said tuned frequency, said amplitude adjustment means being connected to vary the bandwidth and mid-band frequency gain of said circuit such that the product of said bandwidth and mid-band frequency gain is independent of adjustments of said amplitude adjustment means; wherein each of said amplitude circuits comprises: an amplitude circuit input terminal; an amplitude circuit output terminal; a first operational amplifier having an inverting input terminal and an output terminal; an active gyrator having input and output terminals and an inductive impedance; a capacitor; said amplitude adjustment means in the form of an adjustable resistance; means connecting said adjustable resistance, said capacitor and said gyrator in parallel combination between a common junction and ground; a series resistor connected betweEn said amplitude circuit input terminal and said common junction; means connecting the output terminal of said gyrator to said non-inverting input terminal of said first operational amplifier; an input resistor connected between said amplitude circuit input terminal and said inverting input terminal of said first operational amplifier; and a feedback resistor connected between the output and inverting input terminals of said first operational amplifier.

Claim 41

The system according to claim 33 wherein said input and feedback resistors are of equal resistance.

Claim 42

The system according to claim 34 wherein said active gyrator comprises: second and third operational amplifiers, each having an output terminal and inverting and non-inverting input terminals, wherein said capacitor is connected between ground and the non-inverting input terminal of said second operational amplifier; a first resistive impedance connected in series between ground and the inverting input terminal of said second operational amplifier; a second resistive impedance connected in negative feedback relation between the output terminal of said second operational amplifier and the inverting input terminal of that amplifier; a third resistive impedance connected in series between the output terminal of said second operational amplifier and the inverting input terminal of said third operational amplifier; a fourth capacitive impedance connected in negative feedback relation between the output and inverting input terminals of said third operational amplifier; and a fifth resistive impedance connected between the output terminal of said third operational amplifier and the non-inverting input terminal of said second operational amplifier.