I bought this when my in-laws just moved into the house and we couldn't get their cable modem to pick up a signal in their wired smart panel. I bought this to determine which coax connections are working and if any of the existing "spare" coax lines are getting a signal. Within 5 minutes I was able to determine that all of the ports in each room were capable of receiving a signal, but the main connection in their smart panel was not. Save time when you don't know the wiring in your house or just want to look for a signal. Note that this is NOT a signal strength test, it doesn't tell you if there is a signal, it does tell you if it is strong or weak. Just a sign.