Version 4
SHEET 1 880 680
WIRE 16 48 -48 48
WIRE 640 48 96 48
WIRE 432 96 192 96
WIRE 544 96 432 96
WIRE 336 144 256 144
WIRE 432 144 432 96
WIRE 544 144 544 96
WIRE 256 240 256 144
WIRE 336 240 336 224
WIRE 544 240 544 224
WIRE 192 256 192 96
WIRE 224 256 192 256
WIRE 432 272 432 224
WIRE 432 272 288 272
WIRE 640 272 640 48
WIRE 640 272 432 272
WIRE -160 288 -256 288
WIRE -48 288 -48 48
WIRE -48 288 -80 288
WIRE 16 288 -48 288
WIRE 112 288 80 288
WIRE 224 288 112 288
WIRE -256 304 -256 288
WIRE 112 304 112 288
WIRE 256 320 256 304
WIRE -48 336 -48 288
WIRE -256 416 -256 384
WIRE -48 416 -48 400
WIRE 112 416 112 384
WIRE 256 416 256 400
FLAG 112 416 0
FLAG 336 240 0
FLAG 256 416 0
FLAG 544 240 0
FLAG -48 416 0
FLAG -256 416 0
SYMBOL res -64 272 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 10k
SYMBOL res 112 32 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value 10k
SYMBOL voltage -256 288 R0
WINDOW 123 28 96 Left 2
WINDOW 39 0 0 Left 0
SYMATTR Value2 AC 1 0
SYMATTR InstName V1
SYMATTR Value ""
SYMBOL OpAmps\\OP747 256 208 R0
SYMATTR InstName U1
SYMBOL voltage 336 128 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value 15
SYMBOL voltage 256 416 R180
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V3
SYMATTR Value 15
SYMBOL res 416 128 R0
SYMATTR InstName R3
SYMATTR Value 19k
SYMBOL res 528 128 R0
SYMATTR InstName R4
SYMATTR Value 10k
SYMBOL res 96 288 R0
SYMATTR InstName R5
SYMATTR Value 20k
SYMBOL cap 80 272 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C1
SYMATTR Value 15n
SYMBOL cap -64 336 R0
SYMATTR InstName C2
SYMATTR Value 15n
TEXT 24 472 Left 2 !.ac lin 1000 600 1600