Invalid or Vacant Code recordings indicate the caller dialed a non-existant area code and/or office code, or possibly some other sequence of digits that the switching equipment can’t handle. These recordings are different than intercept announcements for specific phone numbers that are changed or unassigned. Occasionally though, they were heard in that context. Generally, vacant code recordings were played by toll and tandem switches, while intercept recordings came from the terminating central office.
Calgary, Alberta CLGRAB04 – Vacant Code Recording (vintage sound/distortion, authentic local accent)
Dallas, Texas DLLSTXTL – Vacant Code Recording 214-1-C (vintage analog sound/authentic local accent)
Jacksonville, Florida JCVLFLCL – Vacant Code Recording 904-3-C (analog sound/authentic local accent)
Manhattan, New York ’10th Avenue’ NYCMNY54 – Vacant Code Recording 212-43 (vintage sound / local accent)
Manhattan, New York (Vesey Tandem 2) NYCMNYZH – Vacant Code Recording 212-7 (analog carrier distortion)