Version 4
SHEET 1 880 680
WIRE 16 32 -16 32
WIRE 128 32 80 32
WIRE 208 32 176 32
WIRE 320 32 272 32
WIRE -16 128 -16 32
WIRE -16 128 -144 128
WIRE 16 128 -16 128
WIRE 128 128 128 32
WIRE 128 128 96 128
WIRE 176 128 176 32
WIRE 176 128 128 128
WIRE 208 128 176 128
WIRE 320 128 320 32
WIRE 320 128 288 128
WIRE 368 128 320 128
WIRE -144 160 -144 128
WIRE 368 256 368 128
WIRE -144 272 -144 240
FLAG 368 256 0
FLAG -144 272 0
FLAG -144 128 Z
SYMBOL Misc\\EuropeanResistor 0 144 R270
WINDOW 0 27 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName R1
SYMATTR Value 19k
SYMBOL cap 80 16 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C1
SYMATTR Value 1u
SYMBOL Misc\\EuropeanResistor 192 144 R270
WINDOW 0 27 56 VTop 2
WINDOW 3 5 56 VBottom 2
SYMATTR InstName R2
SYMATTR Value 1k
SYMBOL cap 272 16 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C2
SYMATTR Value 1u
SYMBOL current -144 240 M180
WINDOW 0 24 80 Left 2
WINDOW 3 24 0 Left 2
WINDOW 123 24 -28 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName I1
SYMATTR Value 0
SYMATTR Value2 AC 1
TEXT -160 -104 Left 2 !.ac dec 100 0.1 10k
TEXT -160 -256 Left 2 ;Z_ = (R1+R2)*((1+jw*R1*R2*(C1+C2)/(R1+R2))/((1+jw*R1*C1)*(1+jw*R2*C2))\nw1=1/T1 = 1/19ms -> f1=1/(2*pi*w1)=8.4Hz\nw2 =1/T2 = 1/1ms -> f2=1/(2*pi*w2)=159.2Hz\nw0 = 1/T0 = 1/1.9ms -> f0=30Hz