Cheap inclinometer

Hi, I have always used a set top box to peak signals and set my dishes up, and thought it was time to see how far i am out doing it this way, I ended up ordering three but only one has turned up, I know the 1.2 is slightly out at the moment, I will see if i can get it any better setting it up the proper way,

I know this one is accurate to 0.5 but it has to be better than guess work that I have used in the past.
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