From Web Page:
An alternative use for the 22kHz tone is to control an external switching box whichfeeds signals from one of a pair of LNBs into the receiver. For example, you could have two separate LNBs on a dish connected to a switching box which is itself connected to the receiver by a single coaxial cable. When the box "hears" a 22kHz tone it swaps to the other LNB.
DiSEqC is an extension of this idea. It relies on a switching box which detects the 22kHz tone pulsing rapidly on and off. In this way, a specially designed receiver can control numerous LNBs through a DiSEqC switching box.
在你连接的中文教程中. 22khz is OFF.我有DiSEQC switch, 118.7&119 LNB接在port1, 其他锅LNB接在port2, 我应该设定22khz ON吧?