Originally posted by Austin
The wideband unit itself gives a 1.8-2.8volt rich to lean signal, which is extremely accurate compared to the digital readout on the meter. You use an inverter/amp card (basically just a voltage divider) to change the signal to a 0-1volt lean to rich. I've tried several different inverter amp cards from Lambdaboy, with several different styles of power supply, and several different calibration curves... none come close.
I wonder whether your "accuracy" problem might be due to "offset voltages." The main OZ DIY guy mentions it here:
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