Version 4
SHEET 1 880 680
WIRE 256 -64 -272 -64
WIRE 320 -64 256 -64
WIRE -272 0 -272 -64
WIRE 320 32 320 -64
WIRE 320 32 32 32
WIRE 320 64 320 32
WIRE 448 64 320 64
WIRE 64 80 -16 80
WIRE 320 80 320 64
WIRE 320 80 288 80
WIRE 64 144 -16 144
WIRE 448 144 288 144
WIRE -272 160 -272 80
WIRE -176 208 -208 208
WIRE 64 208 -96 208
WIRE 384 208 288 208
WIRE 384 224 384 208
WIRE 448 224 384 224
WIRE 32 272 32 32
WIRE 64 272 32 272
WIRE 320 272 288 272
WIRE -272 304 -272 256
WIRE -16 384 -16 144
WIRE 384 384 384 224
WIRE 384 384 -16 384
FLAG -16 80 0
FLAG 320 336 0
FLAG 256 16 0
FLAG 448 288 0
FLAG -272 304 0
SYMBOL Misc\\NE555 176 176 R0
SYMATTR InstName U1
SYMBOL cap 304 272 R0
SYMATTR InstName C1
SYMATTR Value 10n
SYMBOL voltage 256 -80 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value 5
SYMBOL res 432 48 R0
SYMATTR InstName R1
SYMATTR Value 160
SYMBOL res 432 128 R0
SYMATTR InstName R2
SYMATTR Value 160
SYMBOL cap 432 224 R0
SYMATTR InstName C2
SYMATTR Value 100p
SYMBOL npn -208 160 M0
SYMATTR InstName Q1
SYMBOL res -80 192 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 10k
SYMBOL res -288 -16 R0
SYMATTR InstName R4
SYMATTR Value 10k
TEXT -130 358 Left 2 !.tran 10u