I am trying to add 129 and need to know if this combo of DP switches will work with my 811, soon to be a 211. I have two antennas, one at 110 and one at 119. I am currently using Directv LNB's and a legacy SW21 into my 811. I think I need to change to DP LNB'S and I hope I can use two DP21's. One to connect the 110 and 119 and then use one more DP21 to bing in the third Antenna at 129. The antennas are in different locations, the first two, 110 and 119 in location A and 129 will need to be physically separated and hope the SW21's can be use this way. I know a DP34 is the usual answer, it will not work due to the locations of the antennas. Thanks for any replies and expericence with the two DP21's.