I am guessing it's a computer loop call because they phone at 9 am and 2 hours later yet nothing thereafter.  I am on the west coast. They must be on the East coast(6 hours later) because the calls stop, again I am guessing, and start up the following morning repeating calls. I don't know anyone from Pennsylvania so my best guess is Telemarketers. They always change their call numbers if I don't pick up. But if I do answer the call, the same number will phone me for 2 days in a row.