It seems that most surge protectors that are a bit more expensive than the run of the mill ones have ports for coax, Ethernet and phone lines to provide surge protection for these items. I’ve always ignored the Ethernet and phone line ones as I use VOIP and it is unlikely that the VOIP box would generate a surge and same goes for Ethernet. However, when I setup my UPS almost 2 years ago, I figured that connecting the coax for the cable modem into the coax on the UPS would be a good idea in case a surge came in through the cable line, it wouldn’t blow up my cable modem.
As I’ve written about in the last few months, I’ve had some problems with my Internet cutting in and out sometimes and I basically came to the conclusion that it was the router. However, at the same time I replaced the router, I came across a post indicating that the coax surge suppressor will cause signal loss (any coax connection likely does this) and that depending on the suppressor, it might not pass all the frequencies needed for the cable modem. (From what I understand, the newer cable equipment can use higher frequencies. I don’t know enough about this to verify what I’ve read, unfortunately.)
I decided to just connect the coax directly to the cable modem (the coax into my cable modem has no splitters from the street; just a few connections would shouldn’t cause signal loss) and see what happened. Combined with my router change, my cable modem connection has been rock solid. Is all this a coincidence? Who knows, but the signal loss issue is quite possible (the cable tech said that the loss was acceptable, however) and what do I have to lose? If there is a surge through the cable line, I’ll lose the cable modem.
Food for thought if you’re having problems with your cable modem.