Principle of working of diseqc motor
You might want to look at Eutelsat's page on the topic: http://www.eutelsat.com/en/support/technical-support/diseqc.html But put really briefly, the diseqc protocol consists of a 22 kHz tone with at least 600mV amplitude from your set top box or a diseqc 2.0 capable outdoor unit (ODU), such as a Unicable II LNB. Using long and short bursts of 22 kHz you can send binary 1's and 0's to make up a command, such as E0 10 38 FC to select a certain satellite position and polarization from a monoblock LNB (as an example)