Oh, we were getting about 10 junk calls per day in this busy Washington D.C. Metro area. We are about to ditch our landline because I was so tired of it. Decided to try this device and the junk calls have remarkedly decreased about 95%. Our phone is eerily silent; however the real calls are getting through. I just programmed the cell phone jammer as instructed which was very simple to do and it sure seems to be catching the calls. The rare junk call that gets through is using the local area code as a spoof which is the latest thing to make you pick up, but then I can just press the button and block the number. It is amazing so far how many calls are being blocked....it is a big help and makes for a much quieter house!