We had a power surge through the cable tv cable and it killed the TV and damaged the htpc.
First, understand why (how) surges do damage. It is electricity. Therefore it has both an incoming and an outgoing path via your TV. Incoming path was from a cloud. Outgoing path was to earth. What was the best path from cloud to earth via your TV?
Best protection for a cable is a ground block that connects the cable shield to single point earth ground where it enters the building. If that exists, then your cable has the best possible protection - no protector required. So the incoming path could be via AC electric. Outgoing path via the cable. Damage is often on the outgoing path. Many then use speculation that assume the cable was an incoming path. And that surges do not have an outgoing path.
If any wire enters the building without first connecting to earth, then all protection is compromised. TV cable makes that earth connection with a wire. Telephone and AC electric cannot connect directly. So a protector makes that low impedance (ie 'less than 3 meter') connection. Then AC electric is not the incoming and destructive path via a TV.
If a surge current is permitted anywhere inside, then that current will hunt for earth ground destructively via appliances ... without or without that Belkin. BTW, that Belkin does not even claim to protect from the other and destructive type of surge. If only claims to absorb the energy of near zero (thousands) joules. Destructive surges are hundreds of thousands of joules. What harmlessly absorbs that much energy? Single point earth ground.
Protection is a building wide solution. If a 'whole house' protector is not properly earthed, then the Belkin can even give a surge more destructive paths via a TV or any other appliance. No protector stop a destructive surge. Either is makes that low impedance (ie 'less than 3 meter') connection to earth. Or it only claims to protect from another type of surge that typically does not do damage.
