I bought the following MQ8 sensor module.
http://www.ebay.com/itm/MQ8-MQ-8-Hydrogen-Gas-Sensor-Module-for-Arduino-Gas-Sensor-module-/130897191077?ssPageName=ADME:X:AAQ:US:1123
and am using the code given at MQ-8 Hydrogen/H2 Sensor Module | Sandbox Electronics. As per code the RL value after calibration should give values around at 10 k ohm. However I am getting very arbitary values like 20k, 100k etc. Can anyone plz explain this?
Also, about a month back, when hydrogen gas was passed over the sensor, the output(ppm) would change instantly however now the output changes very sluggishly(over several minutes). Also it does not reach the final value.
Could this be the effect of humidity or temperature? Can anyone suggest?