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```
def MQResistanceCalculation(self, raw_adc):
return float(self.RL_VALUE*(1023.0-raw_adc)/float(raw_adc));
```

The thing is, as far as I understand, the ADC works according to this equation:

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`Resolution of ADC / System Voltage = ADC Reading / Analog Voltage Measured`

Furthermore, to get the value of RS in a gas according to the second above-mentioned tutorial, we follow this equation:

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`RS = [(VC x RL) / VRL] - RL`

The Schema of this design is:

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`MQx Sensor -> Logic Level Converter -> MCP3008 -> RPi`

I'm sure I'm missing something, or maybe I'm mixing up things.

Any help is very much appreciated.