Version 4
SHEET 1 880 680
WIRE 96 -16 -160 -16
WIRE 304 -16 96 -16
WIRE 480 -16 304 -16
WIRE 96 16 96 -16
WIRE 304 16 304 -16
WIRE 480 16 480 -16
WIRE 96 128 96 96
WIRE -160 160 -160 -16
WIRE 304 192 304 96
WIRE 304 192 208 192
WIRE 480 192 480 96
WIRE 480 192 416 192
WIRE 96 240 96 192
WIRE 144 240 96 240
WIRE 304 240 304 192
WIRE 352 240 304 240
WIRE 224 288 208 288
WIRE 96 304 96 240
WIRE 224 304 224 288
WIRE 416 304 416 288
WIRE 96 400 96 384
FLAG -160 240 0
FLAG 96 400 0
FLAG 224 304 0
FLAG 416 304 0
SYMBOL zener 112 192 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D1
SYMATTR Value BZX84B33VL
SYMBOL npn 144 192 R0
SYMATTR InstName Q1
SYMATTR Value 2N2222
SYMBOL npn 352 192 R0
SYMATTR InstName Q2
SYMATTR Value 2N2222
SYMBOL res 80 0 R0
SYMATTR InstName R1
SYMATTR Value 10k
SYMBOL res 80 288 R0
SYMATTR InstName R2
SYMATTR Value 10k
SYMBOL res 288 0 R0
SYMATTR InstName R3
SYMATTR Value 100k
SYMBOL res 464 0 R0
SYMATTR InstName R4
SYMATTR Value 100k
SYMBOL voltage -160 144 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value PULSE(10 45 0 1 1)
TEXT -194 424 Left 2 !.tran 1