Hi,Everyone first time poster great board here i have learned so much reading the different threads here. I just upgraded to Directv HD and boy do i love it! I was talking with my installer while he was installing my upgrade and was asking him what were the biggest problems on the HD equipment when he went on service calls.He said mostly dish out of line and bad bcc's.While he was hooking my HR-21 up he showed me the bbc's and told me what they were used for (I already knew from reading on here.) After he got my box up he showed me that i could go to channel 480 and 481 and check the condition of the bbc's to see if they were working right and if one went bad i could call Directv and get a replacement.Do these go out often?How will i know if one goes bad? Thanks for any help and glad to be a new member!