Version 4
SHEET 1 880 680
WIRE -144 16 -288 16
WIRE 112 16 -64 16
WIRE 112 48 112 16
WIRE 240 48 112 48
WIRE 496 80 448 80
WIRE 624 80 576 80
WIRE -288 112 -288 16
WIRE 112 112 112 48
WIRE 448 112 448 80
WIRE 624 112 624 80
WIRE 240 160 240 48
WIRE 240 160 176 160
WIRE 384 160 240 160
WIRE -288 384 -288 192
WIRE 112 384 112 208
WIRE 112 384 -288 384
WIRE 288 384 112 384
WIRE 448 384 448 208
WIRE 448 384 288 384
WIRE 624 384 624 192
WIRE 624 384 448 384
WIRE 288 416 288 384
FLAG 288 416 0
SYMBOL npn 176 112 M0
SYMATTR InstName Q1
SYMATTR Value 2N3904
SYMBOL npn 384 112 R0
SYMATTR InstName Q2
SYMATTR Value 2N3904
SYMBOL voltage -288 96 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value 5
SYMBOL voltage 624 96 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V2
SYMATTR Value 12
SYMBOL res -160 0 M90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 1k
SYMBOL res 592 64 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value 1k
TEXT -320 440 Left 2 !.tran 2m