I have a problem with my modem, i think. Am No dial tone on a telephone line that usually works fine. Originally I had this problem only when a modem picked up to dial and not when I picked up a telephone on the same line, but I started to when it may also record a telephone. The problem comes and goes in unpredictable times. Does Anyone of you knows what specific electrical tests may be the quality of a telephone line measurement, and what values should expect to receive? Is there any way i can test phone line with Digital Multimeter ?