There are two kinds of LNBs for BEV/Dish.
BEV & DirecTV Legacy LNB:
There are the older design (nothing wrong with 'em) "Legacy LNB" which have been around for years.
The are -electrically- interchangable with DirecTV LNBs. (see below)
Mechanically, the BEV/Dish LNBs want to mount on a "D"-shaped arm, and the DirecTV LNBs have a rectangular mounting base for a rectangular arm.
(see pictures on internet - Google is your friend)
These LNBs select left or right circular polarization based on the voltage sent up the coax to them.
The two voltages are nominally 13 and 18 volts.
Over long cable runs, there is some voltage drop and the LNB may not be able to see the higher voltage and change modes.
If you want to bring both left and right polarized signals to your switch or receiver
at the same time, you would need two cables.
BEV/Dish LNBs with DishPro Logo:
To increase cable run length, and reduce the number of cables from LNB to switch, DishPro LNBs and switches were developed.
The left and right polarized signals are both available on the cable at the same time.
They are just translated to different frequency ranges.
One is higher than the other, requiring higher performance cable.
This is called "bandstacking".
Now, one cable can carry both left and right polarized signals at the same time.
Voltage drop on long cable runs is no longer a problem, lending to 200 foot lengths.
All DishPro equipment relies on this feature.
Mix & Match:
Normally, you cannot mix Legacy and DishPro LNBs, switches, and receivers.
Legacy switch examples are: SW21, SW42, SW64
DishPro switch examples are: DP21, DP34, DP44
Note the "SW" and the "DP" (hope I got those model numbers right)
BEV receivers prior to the 3100 were Legacy-friendly, only.
3100's and later, will take -either- Legacy or DishPro LNB/switches.
There are both Legacy and DishPro LNBs which see just one satellite, with one or two connectors.
The confusing name for these are "single" and "dual" (for number of connectors)
Then there are "Twin" and "Quad", which look at two satellites and have either two or four connectors.
Twins and Quads have been built in Legacy and DishPro models, as well.
DirecTV antennas:
The American DirecTV satellite service has three antenna.
The oldest is an 18" dish with one legacy LNB. (sound familiar?)
Then there was a big (possibly 24x36) dish sporting two or three LNBs. The 101 and 119 LNBs are legacy. These were known as "Para Todos" or "Phase II" antennas.
similar to: Phase II .
And now there is a smaller (about 18x20) dish with a single LNB block that looks at three satellites and has a 4-output switch. This is known as the Phase III antenna.
What works:
The little 18" dish/LNB is interchangable with BEV/Dish 18" sporting legacy LNBs.
It's no better, and no worse. Just has a different logo on it.
The Phase II (Para Todos) dish/LNB has its two legacy LNBs mounted farther apart than 9 degrees.
If you move the LNBs to the appropriate spacing, this dish will work fine on 82/91, and may have some increased signal.
Under
no circumstances is the DirecTV Phase III assembly useful on BEV/Dish.