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                                                                 EXHIBIT 10.28.1

THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE UNITED
STATES SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND SUCH
SECURITIES MAY NOT BE OFFERED, SOLD, PLEDGED OR OTHERWISE TRANSFERRED EXCEPT
PURSUANT TO AN EXEMPTION FROM THE REGISTRATION REQUIREMENTS UNDER THE SECURITIES
ACT, AS CONFIRMED IN AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY, AND IN
EACH CASE IN ACCORDANCE WITH ANY OTHER APPLICABLE LAW.


                        LEAP WIRELESS INTERNATIONAL, INC.

                                 PROMISSORY NOTE


$86,501,769                                                San Diego, California
                                                                   April 6, 2001

        FOR VALUE RECEIVED, the undersigned, Leap Wireless International, Inc.,
a Delaware corporation ("Maker"), promises to pay to Century Personal Access
Network, Inc., a Louisiana corporation ("Holder"), on or prior to April 6, 2002
(the "Maturity Date") the principal sum of $86,501,769 (Eighty-Six Million Five
Hundred One Thousand Seven Hundred Sixty-Nine Dollars) in such coin or currency
of the United States of America as at the time of payment shall be legal tender
for the payment of public and private debts, and to pay interest, as hereinafter
provided. On the Maturity Date, Maker shall pay to Holder in full the entire
outstanding principal balance and all accrued and unpaid interest. All payments
shall be applied first to accrued interest and then to the principal balance.
Payments will be made at the office of Maker in lawful money of the United
States of America. All references to dollars are to U.S. dollars.

        SECTION 1. CERTAIN DEFINITIONS. As used in this Note, unless the context
otherwise requires:

        Note means this Promissory Note.

        Purchase Agreement means the Amended and Restated Agreement for Purchase
and Sale of Licenses entered into effective as of November 3, 2000 by and among
Maker, MVI Corp., an Oregon corporation, Century Personal Access Network, Inc.,
a Louisiana corporation, Wisconsin RSA#7, Limited Partnership, a Wisconsin
limited partnership and CenturyTel, Inc. a Louisiana corporation.

        Security Agreement means the Share Pledge Agreement dated as of April 6,
2001 by and between Maker and Holder.

        Vendor Financing Agreements means the vendor financing agreements or
similar credit agreements between Maker and/or its subsidiaries, on the one
hand, and any of Lucent

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Technologies, Inc., Nortel Networks, Inc. and Ericsson Wireless Communications,
Inc. or their respective successors and assigns, on the other hand.

        SECTION 2. INTEREST. Interest shall accrue on the outstanding principal
balance of the Note at the rate of ten percent (10%) per annum, compounded
quarterly. Interest shall be payable in arrears with respect to the outstanding
principal balance on each payment date set forth in Section 3 and on the
Maturity Date. Interest on this Note will be calculated on the basis of a
365-day year and paid for the actual number of days elapsed.

        SECTION 3. PREPAYMENTS.

        (a) Mandatory Prepayments. This Note shall be required to be prepaid by
Maker in accordance with the following schedule:

                        $50,195,458 ($48,032,914 principal plus $2,162,544 in
        accrued interest) on or prior to July 6, 2001;

                        $13,784,673 ($12,822,952 in principal plus $961,721 in
        accrued interest) on or prior to October 6, 2001;

                        $13,464,100 ($12,822,952 in principal plus $641,148 in
        accrued interest) on or prior to January 6, 2002; and

                        the remaining principal amount plus accrued interest on
        or prior to the Maturity Date.

        (b) Optional Prepayment. The Maker may prepay the Note in whole or in
part at any time without premium or penalty.

        SECTION 4. SECURITY. This Note is secured in accordance with the terms
of the Security Agreement.

        SECTION 5. REGISTERED HOLDER. Maker may deem and treat the person in
whose name this Note is registered as the Holder and owner of this Note for the
purpose of receiving payments and for all other purposes, and Maker will not be
affected by any notice to the contrary.

        SECTION 6. OFFICE OF MAKER. So long as any principal of this Note
remains outstanding, this Note may be presented for payment as provided in this
Note at 10307 Pacific Center Court, San Diego, California 92121, Attention:
Chief Executive Officer, unless and until Maker shall designate and maintain
some other office for such purposes and deliver written notice thereof to
Holder.

        SECTION 7. DEFAULT. If Maker fails to pay principal or pay interest
within two (2) business days of when due, or any outstanding indebtedness is
accelerated by the applicable lender or lenders under the Vendor Financing
Agreements, or if Maker fails to perform the terms of the



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Security Agreement or suspends or discontinues its business or makes an
assignment for the benefit of creditors or a composition with creditors or files
a petition in bankruptcy or becomes insolvent or is adjudicated insolvent or
bankrupt or petitions or applies to any tribunal for the appointment of any
receiver, liquidator, or trustee for it or for any substantial part of its
property or assets or commences any proceedings under any bankruptcy,
reorganization, arrangement, readjustment of debt, receivership, dissolution, or
liquidation law or statute of any jurisdiction or there shall be commenced
against Maker any such proceeding which shall remain undismissed for a period of
sixty (60) calendar days or more, or any order, judgment or decree approving the
petition in any such proceeding shall be entered or Maker allows any such
appointment to continue undischarged or unstayed for a period of sixty (60)
calendar days or more or takes any action for the purpose of effecting any of
the foregoing; then an event of default will have occurred. Whenever an event of
default occurs and continues, without any action on the part of Holder, the
entire unpaid balance of this Note shall become immediately due and payable, and
upon such event, Holder may exercise any and all remedies available to it under
this Note, the Security Agreement or otherwise available at law or in equity.

        SECTION 8. INFORMATION. For so long as any indebtedness remains
outstanding under this Note, Maker shall provide to Holder Maker's quarterly
consolidated financial statements not later than forty-five (45) days after the
end of each calendar quarter, and annual audited consolidated financial
statements not later than ninety (90) days after the end of each calendar year.
In addition, Maker shall furnish to Holder such other financial information
concerning Maker as is required to be provided to the lenders under the Vendor
Financing Agreements. In the event Maker provides or receives a notice of
default under any of the Vendor Financing Agreements to or from the lenders
thereunder, Maker shall promptly deliver a copy of each of such notice to
Holder.

        SECTION 9. GENERAL TERMS.

        9.1 Collection. Should any indebtedness evidenced by this Note be
collected by action at law, or in bankruptcy, receivership, or other court
proceedings, or should this Note be placed in the hands of attorneys for
collection after default, Maker agrees to pay, upon demand by Holder, in
addition to principal and interest and other sums, if any, due and payable
hereon, court costs and reasonable attorneys' fees and other reasonable
collection charges. Should Maker be required to bring any action to enforce its
rights under this Note or the Security Agreement, it shall be entitled to an
award of its court costs and reasonable attorneys' fees in such action.

        9.2 No Waiver.

        (a) None of the provisions of this Note, and none of Holder's rights or
remedies on account of any past or future defaults, will be deemed to have been
waived by Holder's acceptance of any past due amount or by any indulgence
granted by Holder to any maker, surety, guarantor or endorser of this Note.

        (b) Maker hereby waives presentment for payment, protest, notice of
protest and notice of nonpayment, and all pleas of division and discussion.
Maker agrees that the release of



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any collateral directly or indirectly securing repayment hereof shall not have
the effect of releasing the Maker, who shall remain liable to Holder, or of
releasing any other collateral that is not expressly released by Holder. Maker
additionally agrees that Holder's acceptance of payment other than in accordance
with the terms of this Note, or Holder's subsequent agreement to extend or
modify such repayment terms, or Holder's failure or delay in exercising any
rights or remedies granted to Holder, shall likewise not have the effect of
releasing Maker from its obligations to Holder, or of releasing any collateral
that directly or indirectly secures repayment hereof. In addition, any failure
or delay on the part of Holder to exercise any of the rights and remedies
granted to Holder shall not have the effect of waiving any of Holder's rights
and remedies. Any partial exercise of any rights and/or remedies granted to
Holder shall furthermore not be construed as a waiver of any other rights and
remedies, it being Maker's intent and agreement that Holder's rights and
remedies shall be cumulative in nature. Maker further agrees that, should any
event of default occur or exist under this Note, any waiver or forbearance on
the part of Holder to pursue the rights and remedies available to Holder, shall
be binding upon Holder only to the extent that Holder specifically agrees to any
such waiver or forbearance in writing. A waiver or forbearance on the part of
Holder as to one event of default shall not be construed as a waiver or
forbearance as to any other event of default.

        9.3 Successors and Assigns Liable. Maker's obligations and agreements
under this Note shall be binding upon Maker's successors, heirs, legatees,
devisees, administrators, executors and assigns. The rights and remedies granted
to Holder under this Note shall inure to the benefit of Holder's successors and
assigns, as well as to any subsequent holder or holders of this Note.

        9.4 Severability. If any provision of the Note is held to be invalid,
illegal or unenforceable by any court, that provision shall be deleted from this
Note and the balance of this Note shall be interpreted as if the deleted
provision never existed.

        9.5 Governing Law. This Note shall be governed by and construed in
accordance with the laws of the State of Delaware.

        9.6 Notices. Any notice to Maker provided for in this Note will be
addressed to it in care of its Secretary, at its principal executive offices in
San Diego, California, and any notice to Holder will be addressed to its address
on file with Maker or to such other address as either may designate to the other
in writing. Any notice shall be deemed to be duly given if and when enclosed in
a properly sealed envelope and addressed as stated above and deposited, postage
prepaid, in a post office or branch post office regularly maintained by the
United States Government. In lieu of giving notice by mail as aforesaid, any
written notice under this Note may be given to Holder by personal delivery or
via facsimile.

        9.7 Waiver of Trial by Jury. To the extent permitted by applicable law,
Maker and Holder hereby waive trial by jury in any litigation in any court with
respect to, in connection with, or arising out of the Purchase Agreement,
Security Agreement or Note, or any document related to the Purchase Agreement,
Security Agreement or Note or the validity, protection, interpretation,
collection or enforcement of the Purchase Agreement, Security Agreement or



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Note. Maker and Holder agree that this provision is a specific and material
aspect of the Note and acknowledges that Holder would not enter into the
Purchase Agreement if this section were not part of the Purchase Agreement,
Security Agreement and Note.

        IN WITNESS WHEREOF, Maker has caused this Note to be signed in its name
by its duly authorized officer and attested by its secretary or an assistant
secretary.

Dated:  April 6, 2001
                                            LEAP WIRELESS INTERNATIONAL, INC.,
                                            a Delaware corporation



                                            By: /s/ JAMES E. HOFFMANN
                                               ---------------------------------

                                            Its: Senior Vice President, General
                                                 Counsel & Secretary
                                                --------------------------------

ATTEST:

 /s/ JAMES E. HOFFMANN
--------------------------------
Secretary



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