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                                                                   Exhibit 10.13

                                    FORM OF
            AMENDMENT NO. 3 TO INTERCARRIER ROAMER SERVICE AGREEMENT

     AMENDMENT NO. 3 TO INTERCARRIER ROAMER SERVICE AGREEMENT ("Amendment No.
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3") dated as of April 4, 2002, by and between AT&T Wireless Services, Inc., a
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Delaware corporation, on behalf of itself and its Affiliates (as hereinafter
defined) (individually and collectively, "AT&T") for the markets listed on
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Schedule 1 to the Roamer Agreement (as hereinafter defined), and Triton PCS
Operating Company L.L.C., a Delaware limited liability company, on behalf of
itself and its Affiliates (individually and collectively, the "Company") for the
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markets listed on Schedule 2 to the Roamer Agreement. Certain capitalized terms
used herein and not otherwise defined have the meaning assigned to such terms in
the Roamer Agreement.

     WHEREAS, AT&T and the Company are party to that certain Intercarrier Roamer
Service Agreement, dated as of February 4, 1998, as amended (the "Roamer
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Agreement"), pursuant to which each of AT&T and the Company made arrangements to
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facilitate the provision of, among other things, voice and voice-related mobile
wireless radio telephone service to the customers of the other Party, while such
customers are using the wireless radio telephone facilities of such Party, and
set forth certain roaming charges in respect thereof;

     WHEREAS AT&T Wireless PCS LLC (an Affiliate of AT&T, "AT&T PCS"), Triton
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PCS License Company L.L.C. (an Affiliate of the Company, "Triton License
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Company") and Triton PCS Holdings, Inc. (an Affiliate of the Company) are
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parties to that certain Exchange and Acquisition Agreement, dated as of November
15, 2001 (the "Exchange and Acquisition Agreement"), pursuant to which, among
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other things, effective upon the closing of the transactions contemplated by the
Exchange and Acquisition Agreement (the "Exchange and Acquisition Closing"),
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Triton License Company will acquire from AT&T PCS a 20 MHz A Block PCS license
covering the entirety of Bulloch and Screven Counties, Georgia (the "Assigned
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Atlanta License"), as more fully described, and upon the terms set forth,
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therein; and

     WHEREAS, pursuant to the Exchange and Acquisition Agreement it was agreed,
and the Company and AT&T PCS desire, that, effective upon the Exchange and
Acquisition Closing (which is occurring as of the date hereof), Schedule 2 and
Exhibit A to the Roamer Agreement be amended to include Bulloch and Screven
Counties, Georgia.

     NOW THEREFORE, in consideration of the mutual promises and covenants herein
contained and for other good and valuable consideration the receipt and
sufficiency of which is hereby acknowledged, the parties hereby agree as
follows:

     1. Amendments. From and after the date hereof, without any further action
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on the part of the parties hereto, the following amendment to the Roamer
Agreement shall be effective and in full force and effect:

     (i) Schedule 2 to the Roamer Agreement shall be amended to include Bulloch
and Screven Counties, Georgia in the Triton market for the Savannah, Georgia BTA
set forth in Item IV therein.

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     2. Severability of Provisions. Any provision of this Amendment No. 3 which
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is prohibited or unenforceable in any jurisdiction shall, as to such
jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions hereof or
affecting the validity or remaining provisions hereof or affecting the validity
or enforceability of such provision in any other jurisdiction.

     3. Agreement to Remain in Full Force and Effect. This Amendment No. 3 shall
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be deemed to be an amendment to the Roamer Agreement. All references to the
Roamer Agreement in any other agreements or documents shall on and after the
date hereof be deemed to refer to the Roamer Agreement as amended hereby. Except
as amended hereby, the Roamer Agreement shall remain in full force and effect
and is hereby ratified, adopted and confirmed in all respects.

     4. Heading. The headings in this Amendment No. 3 are inserted for
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convenience and identification only and are not intended to describe, interpret,
define or limit the scope, extent or intent of this Amendment No. 3 or any
provision thereof.

     5. Counterparts. This Agreement may be executed in counterparts, each of
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which shall be deemed an original, but all of whichtogether shall constitute one
and the same Agreement.

     6. Governing Law. The laws of the State of New York, except those
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pertaining to choice of law, arbitration of disputes and those pertaining to the
time limits for bringing an action that conflicts within the terms of the
Dispute Resolution provision set forth in Section 14.6 of the Roamer Agreement,
shall govern all other substantive matters pertaining to the interpretation and
enforcement and the other terms of this Amendment No. 3 with respect to any
Dispute.

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