* SPICE netlist
XU2 N001 N006 +V 0 N004 LT1013 ;pnba In+)In-)V+)V-)OUT
R1 OUT N002 70K
R2 N009 0 120
R3 N004 N003 1K
Q1 +V N003 N005 0 2N3904
V1 +V 0 15
C1 N010 N005 .1
R4 N006 N010 1Meg
D1 N011 0 1N4148
D2 N008 OUT 1N4148
R5 OUT N001 70K
R6 N007 N006 10K
R7 OUT N007 13K
R8 N007 0 1K
C2 N002 0 .002
C3 N001 0 .1
R9 N009 N005 {R}
XU1 N005 N011 OUT N009 N002 N007 0 N001 LTZ1000 ;pnba 1)2)3)4)5)6)7)8
XU3 N002 N009 +V 0 N008 LT1013 ;pnba In+)In-)V+)V-)OUT
.tran 1000 startup
.meas out param V(out) ; final value of V(out)
.options numdgt=15 measdgt=10 plotwinsize=0
.temp -30 -20 -10 0 10 20 30 40
.step param R list 300K 400K 500K

* LTspice schematic (.asc)
Version 4
SHEET 1 1184 512
WIRE 176 -256 -32 -256
WIRE 240 -256 176 -256
WIRE 304 -256 240 -256
WIRE 592 -256 304 -256
WIRE -32 -240 -32 -256
WIRE 176 -240 176 -256
WIRE 304 -240 304 -256
WIRE 592 -208 592 -256
WIRE -592 -176 -592 -192
WIRE -384 -160 -384 -176
WIRE -144 -144 -352 -144
WIRE 176 -144 176 -160
WIRE 176 -144 -144 -144
WIRE 304 -144 304 -160
WIRE 432 -144 304 -144
WIRE -512 -128 -528 -128
WIRE -416 -128 -432 -128
WIRE 112 -128 32 -128
WIRE -272 -112 -352 -112
WIRE -176 -112 -272 -112
WIRE 112 -112 112 -128
WIRE 176 -112 176 -144
WIRE 240 -112 240 -256
WIRE 304 -112 304 -144
WIRE -384 -80 -384 -96
WIRE -272 -80 -272 -112
WIRE 528 -64 528 -80
WIRE 432 -48 432 -144
WIRE 464 -48 432 -48
WIRE 496 -48 464 -48
WIRE -176 -32 -176 -112
WIRE -128 -32 -176 -32
WIRE -32 -32 -32 -160
WIRE -32 -32 -48 -32
WIRE 64 -32 -32 -32
WIRE 592 -32 592 -144
WIRE 592 -32 560 -32
WIRE 496 -16 432 -16
WIRE -144 16 -144 -144
WIRE -32 16 -32 -32
WIRE 528 16 528 0
WIRE -272 32 -272 0
WIRE 464 32 464 -48
WIRE 64 96 64 -32
WIRE 176 96 176 80
WIRE 176 96 64 96
WIRE -592 128 -592 -80
WIRE -272 128 -272 96
WIRE -272 128 -592 128
WIRE -240 128 -272 128
WIRE 240 128 240 80
WIRE 240 128 -160 128
WIRE 432 128 432 -16
WIRE 432 128 240 128
WIRE 112 144 112 80
WIRE 240 144 240 128
WIRE 576 144 576 128
WIRE -592 192 -592 128
WIRE 32 192 32 -128
WIRE 32 192 -592 192
WIRE -144 240 -144 80
WIRE -32 240 -32 96
WIRE -32 240 -144 240
WIRE 112 240 112 208
WIRE 112 240 -32 240
WIRE 240 240 240 224
WIRE 240 240 112 240
WIRE 304 240 304 80
WIRE 304 240 240 240
WIRE 464 240 464 96
WIRE 464 240 304 240
WIRE 576 240 576 224
WIRE 464 256 464 240
FLAG -384 -80 +V
FLAG 576 128 +V
FLAG 576 240 0
FLAG -592 -192 +V
FLAG -384 -176 0
FLAG 528 -80 0
FLAG 528 16 +V
FLAG 240 -256 OUT
FLAG 464 256 0
SYMBOL opamps\\LT1013 -384 -64 R180
SYMATTR InstName U2
SYMBOL res 288 -256 R0
SYMATTR InstName R1
SYMATTR Value 70K
SYMBOL res 224 128 R0
SYMATTR Value 120
SYMATTR InstName R2
SYMBOL res -416 -144 R90
SYMATTR InstName R3
SYMATTR Value 1K
SYMBOL npn -528 -176 M0
SYMATTR InstName Q1
SYMATTR Value 2N3904
SYMBOL voltage 576 128 R0
SYMATTR InstName V1
SYMATTR Value 15
SYMBOL cap -288 32 R0
SYMATTR InstName C1
SYMATTR Value .1
SYMBOL res -288 -96 R0
SYMATTR InstName R4
SYMATTR Value 1Meg
SYMBOL diode 96 144 R0
SYMATTR InstName D1
SYMATTR Value 1N4148
SYMBOL diode 576 -144 M180
SYMATTR InstName D2
SYMATTR Value 1N4148
SYMBOL res 160 -256 R0
SYMATTR Value 70K
SYMATTR InstName R5
SYMBOL res -32 -48 R90
SYMATTR InstName R6
SYMATTR Value 10K
SYMBOL res -48 -256 R0
SYMATTR InstName R7
SYMATTR Value 13K
SYMBOL res -48 0 R0
SYMATTR InstName R8
SYMATTR Value 1K
SYMBOL cap 448 32 R0
SYMATTR InstName C2
SYMATTR Value .002
SYMBOL cap -160 16 R0
SYMATTR InstName C3
SYMATTR Value .1
SYMBOL res -144 112 R90
SYMATTR InstName R9
SYMATTR Value {R}
SYMBOL References\\LTZ1000 208 -16 R0
SYMATTR InstName U1
SYMBOL opamps\\LT1013 528 32 M180
SYMATTR InstName U3