Once the TV signal voltage 5 V at the antenna input and therefore for the antenna relays provides, on this (audible) to the DBV-T reception. How this tension is activated on each TV set you have to elicit its user! Likewise, if the blocker is required. Because the switch is a completely mechanical apparently, is the DVB-T reception state at no CATV signal on the TV. To switch between reception of CATV and DVB-T, so the signal voltage in the TV set must always be off or turned on, which may be more or less complicated depending on the device. The voltage is passed through the relay to an active DVB-T antenna, which then, for example, with a Kathrein BZD 30 is functioning properly.
