* SPICE netlist
V1 +15V 0 15v
V2 0 -15V 15v
V3 ramp 0 PULSE(0 10 0 {1/freq} 10u 0 {1/freq})
D1 N002 N005 1N4148
C1 N006 ramp 330n
R1 N006 0 47k
XU1 0 N001 +15V -15V N002 TL082 ;pnba In+)In-)V+)V-)OUT
XU2 N006 N004 +15V -15V N004 TL082 ;pnba In+)In-)V+)V-)OUT
R2 N002 N001 100k
R3 N001 N004 100k
D2 N004 N005 1N4148
R4 N005 0 47k
XU3 N005 N003 +15V -15V triangle TL082 ;pnba In+)In-)V+)V-)OUT
R5 triangle N003 120k
R6 N003 0 100k
.SUBCKT TL082 1 2 3 4 5
C1 11 12 3.498E-12
C2 6 7 15.00E-12
DC 5 53 DX
DE 54 5 DX
DLP 90 91 DX
DLN 92 90 DX
DP 4 3 DX
EGND 99 0 POLY(2) (3,0) (4,0) 0 .5 .5
FB 7 99 POLY(5) VB VC VE VLP VLN 0 4.715E6 -5E6 5E6 5E6 -5E6
GA 6 0 11 12 282.8E-6
GCM 0 6 10 99 8.942E-9
ISS 3 10 DC 195.0E-6
HLIM 90 0 VLIM 1K
J1 11 2 10 JX
J2 12 1 10 JX
R2 6 9 100.0E3
RD1 4 11 3.536E3
RD2 4 12 3.536E3
RO1 8 5 150
RO2 7 99 150
RP 3 4 2.143E3
RSS 10 99 1.026E6
VB 9 0 DC 0
VC 3 53 DC 2.200
VE 54 4 DC 2.200
VLIM 7 8 DC 0
VLP 91 0 DC 25
VLN 0 92 DC 25
.tran 0 60ms 0 startup
.SUBCKT LM741 1 2 99 50 28
IOS 2 1 20N
R1 1 3 250K
R2 3 2 250K
I1 4 50 100U
R3 5 99 517
R4 6 99 517
Q1 5 2 4 QX
Q2 6 7 4 QX
C4 5 6 60.3614P
I2 99 50 1.6MA
EOS 7 1 POLY(1) 16 49 1E-3 1
R8 99 49 40K
R9 49 50 40K
V2 99 8 1.63
D1 9 8 DX
D2 10 9 DX
V3 10 50 1.63
EH 99 98 99 49 1
G1 98 9 5 6 2.1E-3
R5 98 9 95.493MEG
C3 98 9 333.33P
G3 98 15 9 49 1E-6
R12 98 15 1MEG
C5 98 15 5.3052E-15
G4 98 16 3 49 3.1623E-8
L2 98 17 530.5M
R13 17 16 1K
F6 50 99 POLY(1) V6 450U 1
E1 99 23 99 15 1
R16 24 23 25
D5 26 24 DX
V6 26 22 0.65V
R17 23 25 25
D6 25 27 DX
V7 22 27 0.65V
V5 22 21 0.18V
D4 21 15 DX
V4 20 22 0.18V
D3 15 20 DX
L3 22 28 100P
RL3 22 28 100K
.step param freq list 220 440 880

* LTspice schematic (.asc)
Version 4
SHEET 1 1568 528
WIRE 160 -248 128 -248
WIRE 288 -248 240 -248
WIRE -720 -152 -720 -232
WIRE 528 -136 480 -136
WIRE 576 -136 528 -136
WIRE 688 -136 656 -136
WIRE 16 -104 -32 -104
WIRE 128 -104 128 -248
WIRE 128 -104 96 -104
WIRE 160 -104 128 -104
WIRE 288 -88 288 -248
WIRE 288 -88 224 -88
WIRE 336 -88 288 -88
WIRE 160 -72 128 -72
WIRE 336 -72 336 -88
WIRE -720 -56 -720 -72
WIRE -720 -56 -784 -56
WIRE -720 -40 -720 -56
WIRE 128 -40 128 -72
WIRE -784 -24 -784 -56
WIRE 528 -24 528 -136
WIRE 560 -24 528 -24
WIRE 688 -8 688 -136
WIRE 688 -8 624 -8
WIRE 784 -8 688 -8
WIRE -64 8 -224 8
WIRE 336 8 336 -8
WIRE 464 8 336 8
WIRE 560 8 464 8
WIRE 336 24 336 8
WIRE 464 40 464 8
WIRE -224 88 -224 8
WIRE -192 88 -224 88
WIRE -64 104 -64 8
WIRE -64 104 -128 104
WIRE -32 104 -32 -104
WIRE -32 104 -64 104
WIRE 336 104 336 88
WIRE 336 104 -32 104
WIRE -720 120 -720 40
WIRE -448 120 -496 120
WIRE -400 120 -448 120
WIRE -304 120 -336 120
WIRE -192 120 -304 120
WIRE -496 152 -496 120
WIRE -304 152 -304 120
WIRE 464 152 464 120
WIRE -304 264 -304 232
FLAG -784 -24 0
FLAG -720 -232 +15V
FLAG -720 120 -15V
FLAG -496 232 0
FLAG -448 120 ramp
FLAG -304 264 0
FLAG 192 -56 -15V
FLAG 192 -120 +15V
FLAG 784 -8 triangle
FLAG -160 136 -15V
FLAG -160 72 +15V
FLAG 128 -40 0
FLAG 464 152 0
FLAG 592 24 -15V
FLAG 592 -40 +15V
FLAG 400 -136 0
SYMBOL voltage -720 -168 R0
SYMATTR InstName V1
SYMATTR Value 15v
SYMBOL voltage -720 -56 R0
SYMATTR InstName V2
SYMATTR Value 15v
SYMBOL voltage -496 136 M0
SYMATTR InstName V3
SYMATTR Value PULSE(0 10 0 {1/freq} 10u 0 {1/freq})
SYMBOL diode 320 -72 R0
SYMATTR InstName D1
SYMATTR Value 1N4148
SYMBOL cap -336 104 R90
SYMATTR InstName C1
SYMATTR Value 330n
SYMBOL res -320 136 R0
SYMATTR InstName R1
SYMATTR Value 47k
SYMBOL Opamps\\opamp2 192 -152 R0
SYMATTR Value TL082
SYMATTR InstName U1
SYMBOL Opamps\\opamp2 -160 40 R0
SYMATTR Value TL082
SYMATTR InstName U2
SYMBOL res 256 -264 R90
SYMATTR InstName R2
SYMATTR Value 100k
SYMBOL res 112 -120 R90
SYMATTR InstName R3
SYMATTR Value 100k
SYMBOL diode 320 88 M180
SYMATTR InstName D2
SYMATTR Value 1N4148
SYMBOL res 448 24 R0
SYMATTR InstName R4
SYMATTR Value 47k
SYMBOL Opamps\\opamp2 592 -72 R0
SYMATTR Value TL082
SYMATTR InstName U3
SYMBOL res 672 -152 R90
SYMATTR InstName R5
SYMATTR Value 120k
SYMBOL res 496 -152 R90
SYMATTR InstName R6
SYMATTR Value 100k