Generally, satellite systems require switching. This means that individual receivers send messages, or change voltage on the coax line, that tells a multiswitch what bank of transponders to send it. With one dish picking up a single satellite, and by using band-stacking with a "stacker", you eliminate all switching, allowing the identical signal to be sent to all receivers. This is why your loop works.
HD *requires* switching, because you go from two banks of transponders to 12 banks. It isn't possible to send that many banks through a single cable without switching; there isn't enough signal bandwidth. And switching requires direct lines.
HD *requires* switching, because you go from two banks of transponders to 12 banks. It isn't possible to send that many banks through a single cable without switching; there isn't enough signal bandwidth. And switching requires direct lines.
