edit to arbors first post, you can indeed use a switch in the output of the dp34. picture is
here. to get 91 my settings were: sw21 dish 1; for 110 - sw21 dish 2, lnb 1; for 119 sw21 dish 2, lnb 2; for 148 sw21 dish 2, lnb 3. so it is possible to add another switch.
for the above poster use 110 for port 1, 119 for port 2 and 91 for port 3. the in your receivers settings set 110 to lnb 1, 119 to lnb 2, and 91 for lnb 3
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