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                                                                EXHIBIT 10.20(f)

                                    AMENDMENT
                                     TO THE
                           REVOLVING CREDIT AGREEMENT
                                 BY AND BETWEEN
       TELEPHONE AND DATA SYSTEMS, INC. AND AERIAL OPERATING COMPANY, INC.

This Fifth Amendment (the "FIFTH AMENDMENT") to the Revolving Credit Agreement
dated as of August 31, 1998, as amended by the First Amendment thereto dated as
of November 3, 1998, by the Second Amendment thereto dated as of February 15,
1999, by the Third Amendment thereto dated as of July 22, 1999 and by the Fourth
Amendment thereto dated as of November 1, 1999 (the "REVOLVING CREDIT
AGREEMENT") by and between Telephone and Data Systems, Inc. ("TDS"), a Delaware
corporation, and Aerial Operating Company, Inc. (the "COMPANY"), a Delaware
corporation, is dated and effective as of this 1st day of November, 1999.
Undefined, capitalized terms shall have the meanings assigned to such terms in
the Revolving Credit Agreement.

                  WHEREAS, TDS and the Company are parties to the Revolving
Credit Agreement and have agreed to enter into this Fifth Amendment on the terms
and conditions set forth herein.

                  NOW, THEREFORE, in consideration of the premises set forth
above, and for good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, and intending to be legally bound, TDS and the
Company agree to amend the Revolving Credit Agreement as follows:

1.       AMENDMENTS TO THE REVOLVING CREDIT AGREEMENT. Effective as of the date
         first above written and subject to the execution of this Fifth
         Amendment by the parties hereto, the Revolving Credit Agreement shall
         be and hereby is amended as follows:

         1.1      The first sentence of SECTION 3 shall be amended (a) to delete
                  the reference to "3%" and to substitute "2.35%" therefor; and
                  (b) to delete the reference to

                  "3-1/2%" and to substitute "2.85%" therefor.

2.       TERMINATION OF REVOLVING CREDIT AGREEMENT GUARANTY. Concurrently with
         the execution of this Fifth Amendment, the unconditional and
         irrevocable guarantee by Aerial Communications, Inc., a Delaware
         corporation ("Guarantor"), of the Company's obligations under the
         Revolving Credit Agreement and the Notes issued thereunder shall be
         terminated and of no further force or effect. TDS, the Company and
         Guarantor shall execute and deliver any additional instruments as may
         be necessary to further evidence the termination of such guarantee.


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3.       CONDITIONS PRECEDENT. This Fifth Amendment shall become effective as of
         the date above written, if, and only if, TDS has received duly executed
         originals of this Fifth Amendment from the Company, Aerial and TDS.

4.       REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company hereby
         represents and warrants as follows:

         4.1      This Fifth Amendment and the Revolving Credit Agreement, as
                  amended hereby, constitute legal, valid and binding
                  obligations of the Company and are enforceable against the
                  Company in accordance with their terms.

         4.2      Upon the effectiveness of this Fifth Amendment, the Company
                  hereby reaffirms all representations and warranties made in
                  the Revolving Credit Agreement, and to the extent the same are
                  not amended hereby, agrees that all such representations and
                  warranties shall be deemed to have been remade as of the date
                  of delivery of this Fifth Amendment, unless and to the extent
                  that any such representation and warranty is stated to relate
                  solely to an earlier date, in which case such representation
                  and warranty shall be true and correct as of such earlier
                  date.

5.       REFERENCE TO AND EFFECT ON THE REVOLVING CREDIT AGREEMENT.

         5.1      Upon the effectiveness of SECTION 1 hereof, on and after the
                  date hereof, each reference in the Revolving Credit Agreement
                  to "this Agreement," "hereunder," "hereof," "herein" or words
                  of like import shall mean and be a reference to the Revolving
                  Credit Agreement as amended hereby, and each reference to the
                  Revolving Credit Agreement in any other document, instrument
                  or agreement shall mean and be a reference to the Revolving
                  Credit Agreement as modified hereby.

         5.2      The Revolving Credit Agreement, as amended hereby, and all
                  other documents, instruments and agreements executed and/or
                  delivered in connection therewith, shall remain in full force
                  and effect, and are hereby ratified and confirmed.

         5.3      Except as expressly provided herein, the execution, delivery
                  and effectiveness of this Fifth Amendment shall not operate as
                  a waiver of any right, power or remedy of TDS, nor constitute
                  a waiver of any provision of the Revolving Credit Agreement or
                  any other documents, instruments and agreements executed
                  and/or delivered in connection therewith.

6.       GOVERNING LAW. This Fifth Amendment shall be governed by and construed
         in accordance with the other remaining terms of the Revolving Credit
         Agreement and the internal laws (as opposed to conflict of law
         provisions) of the State of Illinois.

7.       PARAGRAPH HEADINGS. The paragraph headings contained in this Fifth
         Amendment are and shall be without substance, meaning or content of any
         kind whatsoever and are not a part of the agreement among the parties
         hereto.


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8.       COUNTERPARTS. This Fifth Amendment may be executed in one or more
         counterparts, each of which shall be deemed an original, but all of
         which together shall constitute one and the same instrument.


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                  IN WITNESS WHEREOF, the parties hereto, by their duly
authorized representatives, have executed this Fifth Amendment to the Revolving
Credit Agreement, effective as of the date first written above.




TELEPHONE AND DATA SYSTEMS, INC.               AERIAL OPERATING COMPANY, INC.


By:      /S/ SANDRA L. HELTON                  By:      /S/ DONALD W. WARKENTIN
         ----------------------------------             -----------------------
Name:    Sandra L. Helton                      Name:    Donald W. Warkentin
Title:   Executive Vice President - Finance    Title:   President

The Guarantor hereby consents to the termination of Guarantor's unconditional
and irrevocable guarantee of the Company's obligations under the Revolving
Credit Agreement and the Notes issued thereunder, as set forth in Section 2 of
this Fifth Amendment.

AERIAL COMMUNICATIONS, INC.


By:      /S/ DONALD W. WARKENTIN
         -----------------------
Name:    Donald W. Warkentin
Title:   President