Monitoring O2 sensor/voltage

[bruce plecan]

ref R + C Webb:
As I said, in  GM applications there is a voltage applied to
the O2, It's also mentioned in a Genuine GM Training Manual.
 Again these are late GM EFI applications, what anyone/
everyone else does I won't venture a quess.  If there is any
exception to the above I haven't found it.  I would imagine
other design groups have their own ideas about the proper
way to do it, but that is what makes the world go round.
ZACK's response makes sense to me.
Bruce   This message originated at the world 
            headquarters of cone shaped hat wearers