slaving a receiver is essentially piggy-backing one receiver to another.
Typically you'd use a 4dtv/analog receiver, and a DVB receiver. The one that controls dish movement is usually the "master" and other, the"slave".
WHen you point the dish, the 2nd receiver tags along and is sharing the LNB's primary sat signal.
So if your 4dtv receiver moves the dish, install splitters to send the signal to your DVB box.
BUD Slave Kit Splitters, Switches, DVB MPEG2 Sidecar 4DTV Receiver ....Great Prices
When you tune your 4dtv to say G0 (Galaxy 10R), the DVB receiver could be used to pick up
C band and Ku band digital channels (assuming you have both C and Ku on the dish)
If you slave the other way, DVB does the dish motor drving, you run the IF LOOP output of the DVB receiver to your 4dtv receiver. In this case, the DVB receiver controls the LNB.
My system is setup like the link above at this point, except the Ku on the 4dtv is not hooked up just yet. Soon, but not yet.
Independent Film Channel is on 4dtv satellite X4 (99DegW) Channel 252