The pre-car "O2" sensors are actually Air/Fuel Ratio sensors (aka wide band) and have a different output voltage that ranges from 0 to just over 4 volts.
The post-cat O2 sensors are the older/cheaper narrow band and output a voltage between 0 and 1.0v.
From the screen shot, your air fuel ratio is:
1/Equiv ratio * 14.68 which calculates to 14.70... right where it should be for idle.
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