Version 4
SHEET 1 1820 680
WIRE -112 -528 -144 -528
WIRE -32 -528 -64 -528
WIRE 128 -528 112 -528
WIRE -144 -512 -144 -528
WIRE 224 -480 208 -480
WIRE 336 -480 304 -480
WIRE 432 -480 336 -480
WIRE 480 -480 432 -480
WIRE 640 -480 592 -480
WIRE 784 -480 720 -480
WIRE 864 -480 784 -480
WIRE 960 -480 864 -480
WIRE 128 -464 112 -464
WIRE 432 -448 432 -480
WIRE 592 -448 592 -480
WIRE 960 -448 960 -480
WIRE 336 -432 336 -480
WIRE -144 -416 -144 -432
WIRE 960 -336 960 -368
WIRE -192 -288 -192 -448
WIRE 608 -288 592 -288
WIRE 752 -288 688 -288
WIRE 864 -288 752 -288
WIRE 960 -288 864 -288
WIRE 192 -272 144 -272
WIRE 592 -256 592 -288
WIRE 960 -256 960 -288
WIRE -64 -208 -64 -528
WIRE -16 -208 -64 -208
WIRE 960 -144 960 -176
WIRE -128 -128 -128 -144
WIRE -128 -112 -128 -128
WIRE -64 -112 -64 -208
WIRE -64 -112 -128 -112
WIRE 720 -48 640 -48
WIRE 784 -48 720 -48
WIRE 1024 0 960 0
WIRE 704 16 640 16
WIRE 784 16 704 16
FLAG -112 -528 o
IOPIN -112 -528 Out
FLAG -144 -416 0
FLAG 432 -368 0
FLAG 336 -368 0
FLAG -128 -128 f
FLAG 480 -480 fu
FLAG -192 -496 S
FLAG 592 -368 0
FLAG 784 -480 pd
FLAG 592 -176 0
FLAG 752 -288 pfu
FLAG 560 -48 0
FLAG 336 -192 0
FLAG 336 -272 vf
FLAG 208 -480 o
IOPIN 208 -480 In
FLAG 720 -48 THDx
FLAG 192 -272 S
FLAG 960 -336 0
FLAG 864 -336 0
FLAG 960 -144 0
FLAG 864 -144 0
FLAG 1024 0 THD
IOPIN 1024 0 Out
FLAG 560 16 0
FLAG 704 96 0
SYMBOL e -144 -528 R0
WINDOW 0 40 47 Left 0
WINDOW 3 37 75 Left 0
SYMATTR InstName E1
SYMATTR Value 1
SYMBOL SpecialFunctions\\modulate2 -128 -144 M270
WINDOW 3 -113 112 VLeft 0
WINDOW 123 -58 106 VLeft 0
WINDOW 39 -84 111 VLeft 0
WINDOW 0 51 29 Left 0
SYMATTR Value space=0 mark={2*f2}
SYMATTR Value2 Vhigh={percnt/100}
SYMATTR SpiceLine Vlow={-percnt/100}
SYMATTR InstName A1
SYMBOL ind 416 -464 R0
WINDOW 39 37 40 Left 0
WINDOW 3 -40 80 Left 0
WINDOW 0 33 18 Left 0
SYMATTR SpiceLine Rser=0
SYMATTR Value Flux=x/V(vf)*{Lo}
SYMATTR InstName L1
SYMBOL cap 320 -432 R0
WINDOW 3 -24 101 Left 0
SYMATTR Value Q=x/V(vf)*{Co}
SYMATTR InstName C1
SYMBOL res 320 -496 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R1
SYMATTR Value {Rq}
SYMBOL bv 592 -464 R0
SYMATTR InstName B1
SYMATTR Value V=(V(o)-V(fu))**2
SYMBOL res 624 -464 R270
WINDOW 0 32 56 VTop 0
WINDOW 3 0 56 VBottom 0
SYMATTR InstName R2
SYMATTR Value 1k
SYMBOL bv 592 -272 R0
WINDOW 0 29 43 Left 0
SYMATTR InstName B2
SYMATTR Value V=V(fu)**2
SYMBOL res 592 -272 R270
WINDOW 0 32 56 VTop 0
WINDOW 3 0 56 VBottom 0
SYMATTR InstName R3
SYMATTR Value 1k
SYMBOL bv 656 -48 R90
WINDOW 3 19 34 VTop 0
WINDOW 0 -14 14 VBottom 0
SYMATTR Value V=100*sqrt( V(pd)/V(pfu) )
SYMATTR InstName B3
SYMBOL bv 336 -288 R0
WINDOW 0 27 38 Left 0
SYMATTR InstName B4
SYMATTR Value V=V(f)*f2/1k
SYMBOL SpecialFunctions\\modulate2 -32 -528 R0
WINDOW 3 0 112 Left 0
WINDOW 123 0 130 Left 0
WINDOW 39 0 148 Left 0
WINDOW 0 53 -10 Left 0
SYMATTR Value space=0 mark={40*f2}
SYMATTR Value2 Vhigh=1
SYMATTR SpiceLine Vlow=-1
SYMATTR InstName A3
SYMBOL bi 960 -448 R0
WINDOW 3 13 86 Left 0
SYMATTR Value I=1/V(vf)*I(Vs)-I(Vs)
SYMATTR InstName Bc1
SYMBOL cap 848 -480 R0
WINDOW 3 23 53 Left 0
WINDOW 0 35 20 Left 0
SYMATTR Value {Cf/2}
SYMATTR InstName Cref1
SYMBOL voltage 864 -432 R0
WINDOW 0 -52 17 Left 0
WINDOW 3 -53 52 Left 0
SYMATTR InstName Vs
SYMATTR Value 0
SYMBOL bi 960 -256 R0
WINDOW 3 13 86 Left 0
SYMATTR Value I=1/V(vf)*I(Vs1)-I(Vs1)
SYMATTR InstName Bc2
SYMBOL cap 848 -288 R0
WINDOW 3 23 53 Left 0
WINDOW 0 35 20 Left 0
SYMATTR Value {Cf}
SYMATTR InstName Cref2
SYMBOL voltage 864 -240 R0
WINDOW 0 -52 17 Left 0
WINDOW 3 -53 52 Left 0
SYMATTR InstName Vs1
SYMATTR Value 0
SYMBOL Stepped_Sine1 64 -240 R0
WINDOW 0 0 0 Left 0
WINDOW 39 -106 87 Left 0
SYMATTR InstName X1
SYMATTR SpiceLine f1={f1} f2={f2} cycles={cycles} kd={kd} fmul=SQRT(2)
SYMBOL SpecialFunctions\\sample 864 -16 R0
SYMATTR InstName A2
SYMBOL bi 560 16 R270
WINDOW 0 32 40 VTop 0
WINDOW 3 -32 40 VBottom 0
SYMATTR InstName B5
SYMATTR Value I=u(ddt(V(f)))
SYMBOL voltage 704 0 R0
WINDOW 0 26 37 Left 0
WINDOW 123 0 0 Left 0
WINDOW 39 -106 92 Left 0
WINDOW 3 20 103 Left 0
SYMATTR InstName V1
SYMATTR SpiceLine Rser=1
SYMATTR Value PULSE(0 1 {To-1/f2} 2n 2n 2n)
TEXT -232 -576 Left 0 !.param percnt=0
TEXT -224 -632 Left 0 ;Enter\n2f-Distortion %:
TEXT 32 -648 Left 0 !.param  fo=1k*(1+eps)\n.param Zo=1k Lo=Zo/2/pi/fo Q=5\n.param Co=1/4/pi**2/fo**2/Lo Rq=Zo*Q
TEXT -220 -684 Left 0 !.tran 0 {To} {0.89*kd}
TEXT 600 -552 Left 0 !.param Cf=3u
TEXT 336 -528 Left 0 ;fundamental\nvoltage
TEXT 352 -288 Left 0 ;V=kHz
TEXT 664 -240 Left 0 !.ic V(pfu)=1
TEXT 400 -648 Left 0 !.param eps=2u ;130u for 5*f2 in A3
TEXT 288 -704 Left 0 ;Trick: eps can be used to adjust "virtual"\nresonance frequency at big tmaxstep!
TEXT -40 -496 Left 0 ;sample forcing
TEXT -16 -744 Left 0 ;THD-meter using a tracking filter, stepped frequencies: fn+1/fn=sqrt(2) =fmul
TEXT 112 -104 Left 0 !.param f1=100 f2=10k
TEXT 112 -40 Left 0 !.param cycles=30
TEXT 112 -72 Left 0 !.param k1=f1/f2
TEXT 104 0 Left 0 !.param To=(cycles*2.4118/f1)+kd
TEXT 112 48 Left 0 !.param kd=(cycles+4)/f1
TEXT 1040 -280 Left 0 ;distorsion\npower
TEXT 1032 -472 Left 0 ;fundamental\npower
TEXT 832 -584 Left 0 ;non charge preserving\ncontrolled caps for low\nglitches