Like Osu1991 said, Dish Network's different receiver's signal meters were not calibrated in anyway. Example (Just to give you an idea of what I mean, the numbers are not accurate):
A Dish Network 2700's signal reading of 110% was not the same as a Dish Network 4900's signal reading of 110%.
So Dish Network changed their signal meters , what you call a "Signal MOD" so that all their receivers give similar results for the same signal quality.
Now a 2700's reading of 50% is the same as a 4900's reading of 50%.
This has nothing to do with FTA so you don't have to worry
, unless you also subscribe to Dish Network.
The only "Signal MOD" with FTA is to get a different size dish
(I had to say that
)