There are a few settings in the SKY HD box which are contained in a hidden menu such as the activation of the RF2 port which is used for distribution of the SKY channel to other screens.
To access this menu, press the following button combination:
Press ‘Services’ and then press; 0, 0, 1, and then ‘Select’.
To activate the RF outlet, scroll to the RF output port. toggle to on and press green to save.
This menu also has the setting to change the RF outlet from the default of CH68 if required. This is often required now as the current amplifiers only tune to CH60 which cuts off the SKY channel. More information on this point can be found here