Satellite transmissions use one of 4 bands
horizontal low band
vertical low band
horizontal high band
vertical high band
the H/V switching is done with a 13/18V voltage change, and the hi/lo band switching is done with a 22khz tone which is on/off.
Therefore if one of the receivers switches to a channel which has the band where the 18V is on, and the tone is on, then whatever the other receiver does, it cant switch to any channel on any band apart from the same as the first receiver.
It all get VERY complicated VERY quickly.
With the quad lnb, the boxes have completely independent inputs. |