Version 4
SHEET 1 880 680
WIRE 144 80 112 80
WIRE 32 128 32 112
WIRE 112 128 112 80
WIRE 32 240 32 208
WIRE 112 240 112 208
FLAG 112 240 0
FLAG 144 80 out
FLAG 32 240 0
FLAG 32 112 ctrl
SYMBOL bv 112 112 R0
SYMATTR InstName B1
SYMATTR Value v=abs(idtmod(v(ctrl),0,1,-0.5))*4-1
SYMBOL voltage 32 112 M0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value SINE(3 2 0.1)
TEXT 176 152 Left 2 !.tran 0 10s 0 0.1m