I put 1x (the oscilloscope set 1x probe) probe to Sig and ground to ground(- rail).
detail hook up
Bread Board
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i'm using the coordinate on the(Elenco Precision) bread board.

supply 9.6v battery.(measured 10v)
battery gnd to rail(-)
battery v+ to rail (+)
baby orangutan is connected to (c50-c61)(g50-g61)
Orangutan Vin it's location on bread board is(g50)to (+)rail
orangutan pin PC3 location on board (h56)
(g51) gnd go to (-)rail

baby orangutan b 328 vcc to 5v (5V on the ping sensor) location on board (e36)

Parallax Ping Ultrasonic. locate on board (a35-a37)
gnd (d35) to rail(-)
Signal(sig) to PC3   location on board(d37)

ground(d35) to ground((-) rail).

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