what do the IN and OUT switch do on my tv antenna booster, and the gain knob, how should these be set?

[curtis oshock]

what do the IN and OUT switch do on my tv antenna booster, and the gain knob, how should these be set?

 

[jsmithepa]

IN/OUT very simple: IN from antenna/cable carrier, OUTS to TVs.

Gain knob, I would start it at 50%, and if TV image break up, up gain another 10% at a time.