That's what is referred to as "thousand cycle tone" (1004 Hz) that was traditionally used for setting up analog data circuits. Each and every central office in the country has a unique phone number to access it. This number is usually "top secret" for telco personnel use only.

Even if you had the secret number, you have to dial it from the number you are trying to find, so it wouldn't help you at all. I feel your pain, but unfortunately, there is not canned answer or national number that I've ever heard of.


Ed Vaughn, MBSWWYPBX