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                                                                   Exhibit 10.4
                                PROMISSORY NOTE

$7,000,000                                                      August 10, 2000


        FOR VALUE RECEIVED, the undersigned, LOGIX COMMUNICATIONS
CORPORATION, an Oklahoma corporation ("Borrower"), hereby promises to pay to
the order of DOBSON CC LIMITED PARTNERSHIP, an Oklahoma limited partnership
("Lender"), at 13439 N. Broadway Extension, Suite 200, Oklahoma City,
Oklahoma 73114, the lesser of (i) Seven Million Dollars and no/100
($7,000,000.00) and (ii) the aggregate amount of funds disbursed by Lender to
Borrower and outstanding and unpaid on such date, together with accrued and
unpaid interest thereon (the "Loan").

        The outstanding principal balance of the Loan and accrued interest
thereon shall bear interest at a rate per annum equal to the lesser of (i)
the Maximum Rate (as hereafter defined); or (ii) the "Prime Rate" as
hereafter defined, plus two percent (2.0 %).  Interest shall be computed in
arrears based on a three hundred sixty (360) day year counting the actual
number of days elapsed.

        The "Prime Rate" as used herein shall be the per annum interest rate
announced publicly by the management of Bank of America, N.A. (the "Bank") or
its successor as the Bank's base rate on commercial loans being made, or to
be made, by the Bank in Oklahoma City, Oklahoma as the same may be changed
from time to time.

        Regardless of any provision contained in this Note, Lender shall
never be entitled to contract for, charge, take, reserve, receive, or apply,
as interest on the Loan, or any part thereof, any amount in excess of the
maximum non-usurious rate of interest which, under applicable law, Lender is
permitted to contract for, charge, take reserve, or receive on the Loan
("Maximum Rate"), and if Lender does so, then such excess shall be deemed a
partial prepayment of principal and treated hereunder as such and any
remaining excess shall be refunded to Borrower.  Lender shall not, to the
extent permitted by law, be subject to any penalties provided by any laws for
contracting for charging, taking, reserving, or receiving interest in excess
of the Maximum Rate.

        Interest only shall be payable in quarterly installments beginning
September 30, 2000, and ending December 31, 2001.  Principal shall be paid in
twelve (12) equal quarterly installments beginning March 31, 2002.  All such
principal payments shall include accrued and unpaid interest.  All principal
and accrued interest shall be payable on December 31, 2004.

        The term "Default" means the occurrence of any one or more of the
following events:

        (a)  Failure to pay the interest, principal or any other obligation
under this Note when the same becomes due (whether by its terms, by
acceleration, or otherwise).

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        (b)  If Borrower or Logix Communications Enterprises, Inc. ("Parent")
(i) voluntarily seeks, consents to, or acquiesces in the benefit of any
Debtor Relief Law, OTHER THAN as a creditor or claimant, or (ii) becomes a
party to or is made the subject of any proceeding provided for by any Debtor
Relief Law, OTHER THAN as a creditor or claimant, that could suspend or
otherwise adversely affect the Rights of Lender granted in this Note (UNLESS,
in the event such proceeding is involuntary, the petition instituting same is
dismissed within 30 days after its filing).

        (c) If a default occurs under Parent's 12 1/4% Senior Notes due 2008,
issued by Parent pursuant to an Indenture dated as of June 12, 1998, between
Dobson Wireline, Inc., as issuer, and United States Trust Company of New
York, as trustee.

        (d)  If Borrower or Parent fails to pay when due (after lapse of any
applicable grace periods) any debt (OTHER THAN this Note) in excess
(individually or collectively) of $1,000,000

        (e)  If a default occurs under any other obligation of Borrower or
Parent to Lender.

        (f)  If Borrower or Parent fails, within 60days after entry, to pay,
bond, or otherwise discharge any judgment or order for the payment of money
in excess of $1,000,000 or any warrant of attachment, sequestration, or
similar proceeding against any of Borrower or Parent's assets having a value
(individually or collectively) of $1,000,000 or more which is not stayed on
appeal.

        Upon the occurrence of any event of Default and as often as any event
of Default shall occur, at the option of the holder, the entire indebtedness
evidenced hereby will become due, payable and collectible then or thereafter
as the holder may elect, regardless of the date of maturity hereof.  To the
extent permitted by applicable Law, notice of the exercise of such option is
hereby expressly waived.  Failure by the holder to exercise such option will
not constitute a waiver of the right to exercise the same in the event of any
subsequent default.

        The acceptance by the Lender of any payment which is less than the
total of all amounts due and payable at the time of such payment shall not
constitute a waiver of the right to exercise any of the foregoing remedies or
options at that time or any subsequent time, or nullify any prior exercise of
such remedy or option, without the express consent of the Lender.

        Any sum not paid when due will bear interest at the rate equal to the
lesser of (i) the Maximum Rate, or (ii) five percent (5%) in excess of the
Prime Rate, and such interest which has accrued will be paid at the time of
and as a condition precedent to the curing of any Default hereunder.  During
the existence of any such Default, the holder of this Note may apply payments
received on any amount due hereunder or under the terms of any instrument now
or hereafter evidencing or securing said indebtedness as said holder may
determine.

        The Borrower agrees that if, and as often as, this Note is placed in
the hands of an attorney for collection or to defend or enforce any of the
holder's rights hereunder or under any instrument securing payment of this
Note, the Borrower will pay to the holder its reasonable attorney's fees and
all court costs and other expenses incurred in connection therewith, whether
or not an action shall be instituted to enforce this Note.

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        This Note is issued by the Borrower and accepted by the holder hereof
pursuant to a lending transaction negotiated, consummated and to be performed
in the State of Oklahoma, this Note is to be construed according to the laws
of the State of Oklahoma.

        For the purpose of computing interest under this Note, payments of
all or any portion of the principal sum owing under this Note will not be
deemed to have been made until such payments are received by the holder of
this Note in collected funds.

        If any provision of this Note or the application thereof to any party
or encumbrance is held invalid or unenforceable, the remainder of this Note
and the application of such provision to other parties or circumstances shall
not be affected thereby, the provisions of this Note being severable in any
such instance.

        Each of the Borrower and Lender hereby irrevocably:  (i) submits and
consents, and waives any objection to personal jurisdiction in the State of
Oklahoma for the enforcement of this Note, and (ii) waives any and all
personal rights under the law of any state to object to jurisdiction in the
State of Oklahoma for the purposes of litigation to enforce this Note.  The
Borrower further consents to the venue of any state or federal court sitting
in Oklahoma County, Oklahoma in any action arising under this Note.
Initiating such proceeding or taking such action in any other state shall in
no event constitute a waiver of the agreement contained herein that the law
of the State of Oklahoma shall govern the rights and obligations of the
Borrower and the holder hereunder, or of the submission herein made by the
Borrower to personal jurisdiction within the State of Oklahoma.

        The makers, endorsers, sureties, guarantors and all other persons who
may become liable for all or any part of this obligation severally waive
presentment for payment, protest and notice of nonpayment and notice of
intention to demand payment of this Note.  Said parties consent to any
extension of time (whether one or more) of payment hereof, release of all or
any part of the security for the payment hereof and the release of any party
liable for payment of this obligation.  Any such extension of time or release
may be made at any time and from time to time without notice to any such
party and without discharging said party's liability hereunder.  SUCH PARTIES
FURTHER SEVERALLY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY AND EVERY ACTION OR
PROCEEDING OF ANY KIND OR NATURE UNDER OR BY REASON OF OR RELATING IN ANY WAY
TO THIS NOTE, THE CAPITAL CONTRIBUTION AGREEMENT OR ANY OF THE MATTERS
REFERRED TO HEREIN.

                                        LOGIX COMMUNICATIONS CORPORATION


                                        By:   /s/ Craig T. Sheetz
                                           ----------------------------------
                                                  Craig T. Sheetz
                                                  Executive Vice-President
                                                  and Chief Financial Officer

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