Version 4
SHEET 1 880 680
WIRE 368 -32 160 -32
WIRE 448 -32 368 -32
WIRE 368 0 368 -32
WIRE 160 16 160 -32
WIRE 64 96 48 96
WIRE 160 96 128 96
WIRE 272 112 256 112
WIRE 368 112 368 80
WIRE 368 112 352 112
WIRE 368 144 368 112
WIRE 400 144 368 144
WIRE 160 160 160 96
WIRE 192 160 160 160
WIRE 256 160 256 112
WIRE 368 160 368 144
WIRE -64 208 -96 208
WIRE 32 208 0 208
WIRE 48 208 48 96
WIRE 48 208 32 208
WIRE 96 208 48 208
WIRE 256 208 256 160
WIRE 304 208 256 208
WIRE 320 208 304 208
WIRE -96 256 -96 208
FLAG 32 272 0
FLAG 160 256 0
FLAG 368 256 0
FLAG 528 -32 0
FLAG -96 336 0
SYMBOL npn2 96 160 R0
SYMATTR InstName Q1
SYMATTR Value BC547C
SYMBOL npn2 304 160 R0
SYMATTR InstName Q2
SYMATTR Value BC547C
SYMBOL cap 16 208 R0
SYMATTR InstName C1
SYMATTR Value 1n
SYMBOL cap -64 224 R270
WINDOW 0 32 32 VTop 0
WINDOW 3 0 32 VBottom 0
SYMATTR InstName C2
SYMATTR Value 100n
SYMBOL cap 192 176 R270
WINDOW 0 32 32 VTop 0
WINDOW 3 0 32 VBottom 0
SYMATTR InstName C3
SYMATTR Value 100n
SYMBOL cap 400 160 R270
WINDOW 0 32 32 VTop 0
WINDOW 3 0 32 VBottom 0
SYMATTR InstName C4
SYMATTR Value 100n
SYMBOL res 144 0 R0
SYMATTR InstName R1
SYMATTR Value 1000
SYMBOL res 32 112 R270
WINDOW 0 32 56 VTop 0
WINDOW 3 0 56 VBottom 0
SYMATTR InstName R2
SYMATTR Value 50k
SYMBOL res 256 128 R270
WINDOW 0 32 56 VTop 0
WINDOW 3 0 56 VBottom 0
SYMATTR InstName R3
SYMATTR Value 50k
SYMBOL res 352 -16 R0
SYMATTR InstName R4
SYMATTR Value 1000
SYMBOL voltage 432 -32 R270
WINDOW 0 32 56 VTop 0
WINDOW 3 -32 56 VBottom 0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 12
SYMBOL voltage -96 240 R0
WINDOW 123 24 132 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value SINE()
SYMATTR Value2 AC 0,000050
TEXT -72 368 Left 0 !.ac oct 500 100000 3000000