Version 4
SHEET 1 1072 680
WIRE 320 -352 -64 -352
WIRE 576 -352 320 -352
WIRE 320 -320 320 -352
WIRE -64 -288 -64 -352
WIRE 320 -208 320 -240
WIRE 448 -208 320 -208
WIRE 320 -192 320 -208
WIRE 448 -176 448 -208
WIRE -64 -160 -64 -208
WIRE 576 -48 576 -352
WIRE 320 0 320 -112
WIRE 512 0 320 0
WIRE 448 64 448 -112
WIRE 576 64 576 48
WIRE 576 64 448 64
WIRE 656 64 576 64
WIRE 768 64 720 64
WIRE 896 64 768 64
WIRE 960 64 896 64
WIRE 320 80 320 0
WIRE 576 96 576 64
WIRE 768 96 768 64
WIRE 896 112 896 64
WIRE -48 128 -64 128
WIRE 64 128 32 128
WIRE 192 128 128 128
WIRE 256 128 192 128
WIRE -64 144 -64 128
WIRE 192 224 192 128
WIRE -64 240 -64 224
WIRE 320 240 320 176
WIRE 448 240 448 64
WIRE 576 240 576 176
WIRE 768 240 768 176
WIRE 896 240 896 176
WIRE 192 352 192 304
WIRE 336 352 192 352
WIRE 448 352 448 320
WIRE 448 352 336 352
WIRE 336 384 336 352
WIRE 336 528 336 448
FLAG 320 240 0
FLAG 768 240 0
FLAG -64 -160 0
FLAG -64 240 0
FLAG 960 64 IRQ
FLAG 576 240 0
FLAG 336 528 0
FLAG 896 240 0
SYMBOL voltage -64 -304 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 4
SYMBOL voltage -64 128 R0
WINDOW 0 -78 32 Left 0
WINDOW 3 -185 96 Left 0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value SINE(0 1m 40k 100u 0 0 5)
SYMBOL npn 256 80 R0
SYMATTR InstName Q1
SYMATTR Value BC847B
SYMBOL res 304 -208 R0
SYMATTR InstName R1
SYMATTR Value 10k
SYMBOL res 176 208 R0
SYMATTR InstName R2
SYMATTR Value 100k
SYMBOL res 752 80 R0
SYMATTR InstName R4
SYMATTR Value 10k
SYMBOL cap 720 48 R90
WINDOW 0 0 32 VBottom 0
WINDOW 3 32 32 VTop 0
SYMATTR InstName C1
SYMATTR Value 10n
SYMBOL cap 128 112 R90
WINDOW 0 0 32 VBottom 0
WINDOW 3 32 32 VTop 0
SYMATTR InstName C2
SYMATTR Value 10n
SYMBOL res 48 112 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R5
SYMATTR Value 5k
SYMBOL res 464 336 R180
WINDOW 0 36 76 Left 0
WINDOW 3 36 40 Left 0
SYMATTR InstName R3
SYMATTR Value 100k
SYMBOL cap 352 448 R180
WINDOW 0 24 64 Left 0
WINDOW 3 24 8 Left 0
SYMATTR InstName C3
SYMATTR Value 10n
SYMBOL res 304 -336 R0
SYMATTR InstName R8
SYMATTR Value 1k0
SYMBOL npn 512 -48 R0
SYMATTR InstName Q2
SYMATTR Value BC847B
SYMBOL cap 464 -112 R180
WINDOW 0 24 64 Left 0
WINDOW 3 24 8 Left 0
SYMATTR InstName C4
SYMATTR Value 100n
SYMBOL res 560 80 R0
SYMATTR InstName R6
SYMATTR Value 1k0
SYMBOL cap 912 176 R180
WINDOW 0 24 64 Left 0
WINDOW 3 24 8 Left 0
SYMATTR InstName C5
SYMATTR Value 1n
TEXT -232 16 Left 0 !.tran 0 500u 0