However, the switch only works when the TV
1. has a DVB-T and DVB-C tuner
2. when receiving DVB-T a 5 V voltage to the antenna emits.
3. Receiving stations with DVB-C NO 5 volts to the antenna emits.
Tip: Active DVB-T antenna (even my 20 Cheap antenna) often have an LED, which indicates whether the antenna is supplied with 5V from the TV or not.
I tested the part with a 'Grundig 26 VLE 7100 BF'. This does not satisfy the requirements 1 and 2, but 3 unfortunately. In theory, I can indeed with the remote control the 5V voltage on / off, and then switch the source between DVB-T and C, but that requires more than 10 clicks - because manual repositioning of the antenna is faster.
Only 2 stars, because the manufacturer / supplier has failed to describe the requirements for a successful application is sufficient. A list of devices / manufacturers, which are suitable for use, would be ideal (but I'm afraid that there is currently very little equipment).