Exhibit 12 Joint Filing Agreement Be it known that the undersigned hereby agree to file jointly a Schedule 13D, including amendments thereto, reporting the beneficial ownership of the Class A Common Stock, par value $.01 per share, of Adelphia...

                                                    Exhibit 12




Joint Filing Agreement


        Be it known that the undersigned hereby agree to file
jointly a Schedule 13D, including amendments thereto, reporting the
beneficial ownership of the Class A Common Stock, par value $.01 per
share, of Adelphia Communications Corporation.


Dated: Xxxxxx 0, 0000                  XXX GROUP, INC.
                                       /s/ Xxxxxx X. Xxxxx
                                       Name: Xxxxxx X. Xxxxx
                                       Title: General Counsel and Secretary


Dated: Xxxxxx 0, 0000                  XXX GROUP CAPITAL INC
                                       /s/ Xxxxxx X. Xxxxx
                                       Name: Xxxxxx X. Xxxxx
                                       Title: Secretary


Dated: August 5, 1997                  TELESAT CABLEVISION, INC.
                                       /s/ Xxxxxx X. Xxxxx
                                       Name: Xxxxxx X. Xxxxx
                                       Title: President


Dated: August 5, 1997                  XXXXXXXX INVESTMENTS, INC.
                                       /s/ Xxxxxx X. Xxxxxx
                                       Name: Xxxxxx X. Xxxxxx
                                       Title: Secretary