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                                                                   EXHIBIT 10.33

                                                                       Exhibit A
                                                                       ---------

                                PROMISSORY NOTE


THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED,
AND MAY NOT BE TRANSFERRED, SOLD, OFFERED FOR SALE, HYPOTHECATED OR OTHERWISE
DISPOSED OF IN THE ABSENCE OF AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO
THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.


$________________                                                 June __, 1999


     FOR VALUE RECEIVED, the undersigned, Advanced Radio Telecom Corp., a
Delaware corporation (the "Borrower"), hereby promises to pay to ____________
(the "Lender"), or order, on the Maturity Date (as defined below), the principal
sum of $___________, together with interest at a rate of eleven percent (11%)
per annum on the aggregate principal amount of the Note from time to time
unpaid, which interest shall accrue daily but not compound.  The Maturity Date
shall be the first to occur of (i) the Final Maturity Date (as defined in the
Preferred Stock Purchase Agreement dated as of June __, 1999, as from time to
time in effect, by and among the Borrower, the Lender and the other parties
thereto (the "Agreement")) and (ii) the date the Lender or the Borrower
terminates the Agreement pursuant to Section 6 thereof.

     This Note evidences borrowings under, and is entitled to the benefits of,
and is subject to the provisions of the Agreement.  The principal of this Note
may be prepaid without penalty in whole or from time to time in part.  All
payments made under this Note shall be made by wire transfer of immediately
available funds in accordance with the instructions contained in the Agreement,
as amended by the Lender in writing from time to time.

     If the Borrower shall default in the payment of any principal of or accrued
interest on this Note when the same is due and payable, the Borrower agrees to
pay, to the extent permitted by law, interest on such defaulted amount at the
rate of fourteen percent (14%) per annum until all amounts due hereunder are
paid in full.

     In the event that (a) the Borrower (i) voluntarily files for protection
under any bankruptcy or insolvency law, or appoints or consents to the
appointment of a receiver or makes a general assignment for the benefit of
creditors or (ii) has filed against it any petition commencing an involuntary
case under any bankruptcy or insolvency law and such case is not dismissed
within sixty (60) days of such filing or (b) obligations of the Borrower under
either
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(i) the Indenture dated as of February 6, 1997 between the Borrower and
The Bank of New York, as Trustee or (ii) obligations of the Borrower with
respect to money borrowed under the Credit Agreement dated September 17, 1998
between the Borrower and Lucent Technologies, Inc. ("Lucent") and the Working
Capital Credit Agreement dated September 17, 1998 between the Borrower and
Lucent (collectively, the "Lucent Loan") are accelerated and such acceleration
is not withdrawn (each of the above events, an "Event of Default"), then the
Lender may by notice in writing to the Borrower declare all or any part of the
unpaid principal of this Note, together with accrued interest thereon, due and
payable (unless pursuant to clause (a), in which case the entire unpaid
principal of this Note, together with accrued interest thereon, shall
automatically become immediately due and payable) and the Lender shall have the
right to enforce this Note by exercise of the rights and remedies granted to it
by applicable law.  No failure by the Lender to take action with respect to any
Event of Default hereunder shall affect its subsequent rights to take action
with respect to the same or any other Event of Default.  In the event of any
Event of Default the Borrower agrees to pay all reasonable costs of collection,
including reasonable attorneys' fees, to the extent allowed by law.

     If any Event of Default occurs hereunder, the Lender may protect and
enforce its rights by suit in equity, action at law and/or other appropriate
proceeding for specific performance of this Note.

     This Note shall be governed by and construed in accordance with the laws
(other than the conflict of laws rules) of the State of New York.

     The Borrower hereby waives presentment, demand, notice, protest and all
other demands and notices in connection with the delivery, acceptance,
performance and enforcement of this Note, except as specifically otherwise
provided in the Agreement, and assents to extensions of time of payment,
forbearance or other indulgence without notice.

     Acceptance by the Lender of any payment hereunder which is less than
payment in full of all amounts due and payable at the time of such payments
shall not constitute a waiver of the right to demand payment in full at that
time or any subsequent time.  No modification or waiver of any provision of this
Note, nor any departure therefrom, shall in any event be effective unless the
same shall be in a written instrument signed by the Lender and then such waiver
or consent shall be effective only in the specific instance and for the specific
purpose given.

     This Note is one of the several notes in an aggregate principal amount of
$50,000,000 (together, the "Bridge Notes") made by the Borrower in favor of the
Lender and the other parties to the Agreement pursuant to Section 1.3 of the
Agreement.  All action in connection with the enforcement of, or the exercise of
any remedies in respect of, the Bridge Notes shall be taken only by two-thirds
in interest of the holders of the Bridge Notes, and all such actions shall be
binding on all of the holders of the Bridge Notes.

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     This Note may be amended upon the written consent of the Borrower and the
Lender.

[SEAL]                        ADVANCED RADIO TELECOM CORP.


                              By
                                ---------------------------------
                                  Title:

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