Version 4
SHEET 1 2600 1816
WIRE 784 256 400 256
WIRE 960 256 960 240
WIRE 960 256 784 256
WIRE 640 272 352 272
WIRE 1168 272 640 272
WIRE 352 288 352 272
WIRE 640 288 640 272
WIRE -48 352 -48 336
WIRE 960 368 960 256
WIRE 1168 368 1168 272
WIRE 352 384 352 368
WIRE 416 384 352 384
WIRE 528 384 480 384
WIRE 896 416 880 416
WIRE 1104 416 1088 416
WIRE -48 448 -48 432
WIRE -48 448 -64 448
WIRE 784 448 784 256
WIRE -48 464 -48 448
WIRE 400 464 400 256
WIRE 752 464 688 464
WIRE 352 480 352 384
WIRE 368 480 352 480
WIRE 880 480 880 416
WIRE 880 480 816 480
WIRE 960 480 960 464
WIRE 1088 480 1088 416
WIRE 1088 480 960 480
WIRE 1168 480 1168 464
WIRE 1280 480 1168 480
WIRE 1392 480 1360 480
WIRE 1504 480 1392 480
WIRE 1552 480 1504 480
WIRE 528 496 528 384
WIRE 528 496 432 496
WIRE 544 496 528 496
WIRE 640 496 640 368
WIRE 640 496 624 496
WIRE 736 496 640 496
WIRE 752 496 736 496
WIRE 960 496 960 480
WIRE 1168 496 1168 480
WIRE 1392 496 1392 480
WIRE 1504 496 1504 480
WIRE 240 512 160 512
WIRE 368 512 320 512
WIRE 640 528 640 496
WIRE 736 528 736 496
WIRE 160 544 160 512
WIRE 880 544 880 480
WIRE 896 544 880 544
WIRE 1088 544 1088 480
WIRE 1104 544 1088 544
WIRE -48 560 -48 544
WIRE 1392 592 1392 560
WIRE 1504 592 1504 576
WIRE 640 624 640 592
WIRE 688 624 688 464
WIRE 688 624 640 624
WIRE 736 624 736 592
WIRE 736 624 688 624
WIRE 688 640 688 624
WIRE 160 656 160 624
WIRE 400 672 400 528
WIRE 784 672 784 512
WIRE 784 672 400 672
WIRE 960 672 960 592
WIRE 960 672 784 672
WIRE 1168 672 1168 592
WIRE 1168 672 960 672
WIRE 960 688 960 672
FLAG 688 640 0
FLAG 1392 592 0
FLAG 1552 480 out
FLAG 160 656 0
FLAG -64 448 0
FLAG -48 560 VN10
FLAG -48 336 VP10
FLAG 960 240 VP10
FLAG 960 688 VN10
FLAG 1504 592 0
SYMBOL Opamps\\LT1361 400 432 R0
SYMATTR InstName U1
SYMBOL cap 480 368 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C1
SYMATTR Value 680p
SYMBOL res 640 480 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 1k
SYMBOL Opamps\\LT1361 784 416 R0
SYMATTR InstName U2
SYMBOL diode 624 528 R0
SYMATTR InstName D1
SYMBOL diode 752 592 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D2
SYMBOL npn 896 368 R0
SYMATTR InstName Q1
SYMATTR Value BC547C
SYMBOL pnp 896 592 M180
SYMATTR InstName Q2
SYMATTR Value BC557C
SYMBOL res 368 272 M0
SYMATTR InstName R2
SYMATTR Value 10k
SYMBOL res 656 272 M0
SYMATTR InstName R3
SYMATTR Value 10k
SYMBOL ind 1376 464 R90
WINDOW 0 5 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName L1
SYMATTR Value 20µ
SYMBOL cap 1376 496 R0
SYMATTR InstName C2
SYMATTR Value 470n
SYMBOL res 336 496 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R4
SYMATTR Value 1k
SYMBOL voltage 160 528 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value SINE(0 1 {f})
SYMBOL voltage -48 336 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V2
SYMATTR Value 10
SYMBOL voltage -48 448 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V3
SYMATTR Value 10
SYMBOL res 1488 480 R0
SYMATTR InstName R5
SYMATTR Value 6.5
SYMBOL npn 1104 368 R0
SYMATTR InstName Q3
SYMATTR Value MJE340
SYMBOL pnp 1104 592 M180
SYMATTR InstName Q4
SYMATTR Value MJE350
TEXT 1360 384 Left 2 !.opt plotwinsize=0\n.opt numdgt=8\n.opt method=gear
TEXT 1376 288 Left 2 !.param f=5k
TEXT 1368 328 Left 2 !.tran {2/f}