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                                                                   Exhibit 4.3.6

                  FIFTH AMENDMENT, dated as of October 31, 1997 (this "FIFTH
AMENDMENT"), to the AMENDED AND RESTATED CREDIT AGREEMENT, dated as of 
November 19, 1996 (as amended, supplemented or otherwise modified from time to
time, the "CREDIT AGREEMENT"), among PAXSON COMMUNICATIONS CORPORATION, a
Delaware corporation (the "BORROWER"), the lenders from time to time party
thereto (the "LENDERS") and UNION BANK OF CALIFORNIA, N.A., as Agent.

                              W I T N E S S E T H :
                              - - - - - - - - - - 

                  WHEREAS, the parties hereto wish to amend certain provisions
of the Credit Agreement, but only on the terms and subject to the conditions set
forth herein;

                  NOW, THEREFORE, in consideration of the premises and of the
mutual agreements herein contained, the parties hereto agree as follows:

                  1. DEFINITIONS. Unless otherwise defined herein, terms defined
in the Credit Agreement shall be used as so defined.

                  2. AMENDMENT TO CREDIT AGREEMENT. Subsection 5.14 of the
Credit Agreement is hereby amended by deleting the date "November 1, 1997" where
it appears in such subsection and substituting in lieu thereof the date
"November 19, 1997".

                  3. EFFECTIVE DATE. This Fifth Amendment will become effective
as of the date (the "EFFECTIVE DATE") hereof upon its execution by the Borrower
and the Required Lenders in accordance with the terms of the Credit Agreement.

                  4. REPRESENTATIONS AND WARRANTIES. The Borrower represents and
warrants to each Lender that (a) this Fifth Amendment constitutes the legal,
valid and binding obligation of the Borrower, enforceable against it in
accordance with its terms, except as such enforcement may be limited by
bankruptcy, insolvency, fraudulent conveyances, reorganization, moratorium or
similar laws affecting creditors' rights generally, by general equitable
principles (whether enforcement is sought by proceedings in equity or at law)
and by an implied covenant of good faith and fair dealing, (b) the
representations and warranties made by the Loan Parties in the Loan Documents
are true and correct in all material respects on and as of the date hereof
(except to the extent that such representations and warranties are expressly
stated to relate to an earlier date, in which case such representations and
warranties shall have been true and correct in all material respects on and as
of such earlier date) and (c) no Default or Event of Default has occurred and is
continuing as of the date hereof.

                  5. CONTINUING EFFECT. Except as expressly waived or amended
hereby, the Credit Agreement shall continue to be and shall remain in full force
and effect in accordance with its terms.



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                                                                              2

                  6. GOVERNING LAW. THIS FIFTH AMENDMENT SHALL BE GOVERNED BY,
AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW
YORK.

                  7. COUNTERPARTS. This Fifth Amendment may be executed by the
parties hereto in any number of separate counterparts and all of said
counterparts taken together shall be deemed to constitute one and the same
instrument.

                  8. PAYMENT OF EXPENSES. The Borrower agrees to pay and
reimburse the Agent for all of its out-of-pocket costs and reasonable expenses
incurred in connection with this Fifth Amendment, including, without limitation,
the reasonable fees and disbursements of counsel to the Agent.



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                                                                             3

                  IN WITNESS WHEREOF, the parties hereto have caused this Fifth
Amendment to be duly executed and delivered by their properly and duly
authorized officers as of the day and year first above written.

                                       PAXSON COMMUNICATIONS
                                       CORPORATION
                                       
                                       By: /s/ Arthur Tek
                                          -------------------------------------
                                          Title: TREASURER
                                       
                                       
                                       
                                       UNION BANK OF CALIFORNIA, N.A., as
                                       Agent
                                       
                                       
                                       By: /s/ Christine P. Ball
                                          -------------------------------------
                                          Title: Vice President
                                       
                                       
                                       
                                       THE BANK OF NEW YORK
                                       
                                       
                                       By: /s/ CYNTHIA L. ROGERS
                                          -------------------------------------
                                          Title: CYNTHIA L. ROGERS
                                                 A.V.P.
                                       
                                       
                                       CIBC, INC.
                                       
                                       
                                       By: /s/ William Phoenix
                                          -------------------------------------
                                          Title: DIRECTOR WILLIAM PHOENIX
                                                 SECURITIES CORP., AS AGENT
                                       
                                       
                                       BANKBOSTON, N.A.
                                       
                                       By: /s/ MIKE MACKEAN
                                          -------------------------------------
                                          Title: DIRECTOR
                                       
                                       
                                       
                                       
                                       
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                                                                              4

                                      FIRST UNION NATIONAL BANK OF NORTH
                                      CAROLINA
                                      
                                      
                                      By: /s/ BRUCE W. LOFTIN
                                         -------------------------------------
                                         Title: BRUCE W. LOFTIN
                                                SENIOR VICE PRESIDENT
                                      
                                      
                                      
                                      
                                      ABN-AMRO BANK N.V.
                                      ABN AMRO NORTH AMERICA, INC.
                                      
                                      
                                      By: /s/ [ILLEGIBLE]
                                          ------------------------------------
                                          Title: VP
                                      
                                      
                                      
                                      BANK OF AMERICA NT&SA
                                      
                                      
                                      By: /s/ CARL F. SALAS
                                          ------------------------------------
                                          Title: VICE PRESIDENT
                                                 CARL F. SALAS
                                      
                                      
                                      
                                      BANK OF MONTREAL
                                      
                                      
                                      By: /s/ W.T. CALDER
                                          -------------------------------------
                                          Title: W.T. CALDER
                                                 DIRECTOR
                                      
                                      
                                      
                                      BARNETT BANK, N.A.
                                      
                                      By: 
                                          -------------------------------------
                                          Title:
                                      
                                      
                                      
                                      
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                                                                              5

                                      FLEET NATIONAL BANK
                                      
                                      
                                      By: /s/ EILEEN M. BURKE
                                          -------------------------------------
                                          Title: SVP
                                      
                                      
                                      
                                      LTCB TRUST COMPANY
                                      
                                      
                                      By: /s/ PHILIP FREEMAN
                                          -------------------------------------
                                          Title: SVP
                                      
                                      
                                      
                                      THE SUMITOMO BANK, LIMITED
                                      
                                      
                                      By: /s/ ALLEN HARWELL
                                          -------------------------------------
                                          Title: 
                                      
                                      
                                      By: /s/ M. PHILLIP FREEMAN
                                          -------------------------------------
                                          Title: M. PHILLIP FREEMAN
                                                 VICE PRESIDENT
                                      
                                      
                                      SUNTRUST BANK, CENTRAL FLORIDA, N.A.
                                      
                                      
                                      By: /s/ ALLEN HARWELL
                                          -------------------------------------
                                          Title: VICE PRESIDENT