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                                                                    Exhibit 4.62

April 14, 2003

Speedcom Wireless Corporation
7020 Professional Parkway East
Sarasota, Florida 34240

     RE: Letter Loan Agreement

Ladies and Gentlemen:

     1. Loan. This letter when fully executed will constitute a loan agreement
(the "Agreement") between SDS Merchant Fund, L.P. (the "Lender"), and Speedcom
Wireless Corporation, a Delaware corporation (the "Borrower"), pursuant to which
the Lender, on the terms and conditions provided herein, shall agree to make one
or more loans to or for the benefit of the Borrower hereunder (the "Loan"),
provided the aggregate principal amount of the Loan shall not exceed One Hundred
Thousand Dollars ($100,000.00). The day on which the Lender makes the Loan is
referred to herein as the "Closing Date." The Lender's obligation to make the
Loan is subject to the Borrower's fulfillment of each of the applicable
conditions set forth in Section 4 hereof.

     2. Loan Documents.

          a. Note. The Loan shall be evidenced by a promissory note issued to
the Lender in the principal amount of the Loan in the form attached hereto as
Exhibit A (together with any replacements and substitutes therefor, the "Note").
The principal amount of the Loan and interest thereon, calculated at the rate of
15% per annum as provided in the Note, shall be payable as set forth more
particularly therein.

          b. Security Agreement. The Loan shall be secured by a continuing
security interest in all of the property and assets of the Borrower pursuant to
the terms of a security agreement in the form attached hereto as Exhibit B (the
"Security Agreement").

          c. This Agreement, the Note, the Security Agreement and each other
document which evidences and/or secures the Loan are hereinafter collectively
referred to as the "Loan Documents."

     3. Term and Termination. Subject to Section 6 hereof, the aggregate
principal amount of the outstanding Note and all accrued and unpaid interest
thereon and other sums owing hereunder and thereunder shall be due and payable
on the earlier (the "Maturity Date") of: (i) December 31, 2003, or (ii) the
acceleration of the obligations as contemplated by this Agreement. The Maturity
Date may be extended as agreed upon in writing between the parties.

     4. Conditions Precedent.

          a. Documents to be Delivered. The obligation of the Lender to make the
Loan is subject to the due execution and delivery by the Borrower (or the
Borrower causing the

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due execution and delivery) to the Lender of each of the following (all
documents to be in form and substance satisfactory to the Lender and its
counsel):

               i. This Agreement, the Note, the Security Agreement and each
other instrument, agreement and document to be executed and/or delivered
pursuant to this Agreement and/or the instruments, agreements and documents
referred to in this Agreement.

               ii. A certified copy of the resolutions of the Board of Directors
(or if the Board of Directors takes action by unanimous written consent, a copy
of such unanimous written consent containing all of the signatures of the
members of the Board of Directors) of the Borrower, dated as of the Closing
Date, authorizing the execution, delivery and performance of the Loan Documents.

               iii. A certificate, dated as of the Closing Date, signed by an
executive officer of the Borrower to the effect that the representations and
warranties set forth in Section 5 of this Agreement are true and correct as of
the Closing Date.

               iv. The Borrower shall have filed all UCC financing statements in
form and substance satisfactory to the Lender at the appropriate offices to
create a valid and perfected security interest in the Collateral (as defined in
the Security Agreement).

          b. Absence of Certain Events. The occurrence of a Material Adverse
Effect (as defined below) shall not have occurred or be occurring as of the
Closing Date.

     5. Representations and Warranties. To induce the Lender to make the Loan,
the Borrower hereby represents and warrants to the Lender that at and as of the
date hereof:

          a. The Borrower has been duly incorporated and is validly existing and
in good standing under the laws of the state of Delaware, with full corporate
power and authority to own, lease and operate its properties and to conduct its
business as currently conducted. The Borrower is duly qualified as a foreign
entity to do business and is in good standing in every jurisdiction in which its
ownership of property or the nature of the business conducted by it makes such
qualification necessary and where the failure so to qualify would have a
Material Adverse Effect. "Material Adverse Effect" means any material adverse
effect on the ability of the Borrower to perform its obligations hereunder or on
the business, operations, properties, prospects or financial condition of the
Borrower.

          b. Each of the Loan Documents has been duly authorized, validly
executed and delivered on behalf of the Borrower and is a valid and binding
obligation of the Borrower enforceable against the Borrower in accordance with
its terms, subject to limitations on enforcement by general principles of equity
and by bankruptcy or other laws affecting the enforcement of creditors' rights
generally, and the Borrower has full power and authority to execute and deliver
this Agreement and the Loan Documents and to perform its obligations hereunder
and thereunder.

          c. The execution, delivery and performance of this Agreement and the
Loan Documents will not (i) conflict with or result in a breach of or a default
under any of the terms or provisions of, (A) the Borrower's certificate of
incorporation or by-laws, or (B) any material provision of any indenture,
mortgage, deed of trust or other material agreement or instrument to which the
Borrower is a party or by which it or any of its material properties or assets
is bound,

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(ii) result in a violation of any material provision of any law, statute, rule,
regulation, or any existing applicable decree, judgment or order by any court,
Federal or state regulatory body, administrative agency, or other governmental
body having jurisdiction over the Borrower, or any of its material properties or
assets or (iii) result in the creation or imposition of any material lien,
charge or encumbrance upon any material property or assets of the Borrower or
any of its subsidiaries pursuant to the terms of any agreement or instrument to
which any of them is a party or by which any of them may be bound or to which
any of their property or any of them is subject.

          d. No consent, approval or authorization of or designation,
declaration or filing with any governmental authority on the part of the
Borrower is required in connection with the valid execution and delivery of this
Agreement or the Loan Documents.

All representations and warranties made by the Borrower under or in connection
with this Agreement shall survive the making of the Loan and issuance and
delivery of the Note to the Lender, notwithstanding any investigation made by
the Lender or on the Lender's behalf. All statements contained in any
certificate or financial statement delivered by the Borrower to the Lender under
this Agreement or any other Loan Document shall constitute representations and
warranties made by the Borrower hereunder.

     6. Events of Default; Remedies. Upon the occurrence of any of the following
(each, an "Event of Default"):

          a. the Borrower shall fail to make the payment of any amount of any
principal outstanding after the date such payment shall become due and payable
hereunder; or

          b. the Borrower shall fail to make any payment of interest after the
date such interest shall become due and payable hereunder; or

          c. any representation, warranty, covenant or certification made by the
Borrower herein, in the Note, any other Loan Document or in any certificate or
financial statement shall prove to have been false or incorrect or breached in a
material respect on the date as of which made; or

          d. the Borrower or any of its subsidiaries shall (i) default in any
payment of any amount or amounts of principal of or interest on any indebtedness
for borrowed money (the "Indebtedness") (other than the Indebtedness hereunder)
the aggregate principal amount of which Indebtedness of all such persons is in
excess of $100,000, whether such Indebtedness now exists or shall hereinafter be
created, and such default entitles the holder thereof to declare such
indebtedness to be due and payable, and such indebtedness has not been
discharged in full or such acceleration has not been stayed, rescinded or
annulled within twelve (12) business days of such acceleration, or (ii) default
in the observance or performance of any other agreement or condition relating to
any Indebtedness in excess of $100,000 or contained in any instrument or
agreement evidencing, securing or relating thereto, or any other event shall
occur or condition exist, the effect of which default or other event or
condition is to cause, or to permit the holder or holders or beneficiary or
beneficiaries of such Indebtedness to cause with the giving of notice if
required, such Indebtedness to become due prior to its stated maturity; or

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          e. A judgment or order for the payment of money shall be rendered
against the Borrower or any subsidiary in excess of $100,000 in the aggregate
(net of any applicable insurance coverage) for all such judgments or orders
against all such persons (treating any deductibles, self insurance or retention
as not so covered) that shall not be discharged, and all such judgments and
orders remain outstanding, and there shall be any period of thirty (30)
consecutive days following entry of the judgment or order in excess of $100,000
or the judgment or order which causes the aggregate amount described above to
exceed $100,000 during which a stay of enforcement of such judgment or order, by
reason of a pending appeal or otherwise, shall not be in effect; or

          f. the Borrower shall (i) apply for or consent to the appointment of,
or the taking of possession by, a receiver, custodian, trustee or liquidator of
itself or of all or a substantial part of its property or assets, (ii) admit in
writing its inability to pay its debts as such debts become due, (iii) make a
general assignment for the benefit of its creditors, (iv) commence a voluntary
case under the Bankruptcy Code or under the comparable laws of any jurisdiction
(foreign or domestic), (v) file a petition seeking to take advantage of any
bankruptcy, insolvency, moratorium, reorganization or other similar law
affecting the enforcement of creditors' rights generally, (vi) acquiesce in
writing to any petition filed against it in an involuntary case under the
Bankruptcy Code or under the comparable laws of any jurisdiction (foreign or
domestic), or (vii) take any action under the laws of any jurisdiction (foreign
or domestic) analogous to any of the foregoing; or

          g. a proceeding or case shall be commenced in respect of the Borrower
or any of it's subsidiaries without its application or consent, in any court of
competent jurisdiction, seeking (i) the liquidation, reorganization, moratorium,
dissolution, winding up, or composition or readjustment of its debts, (ii) the
appointment of a trustee, receiver, custodian, liquidator or the like of it or
of all or any substantial part of its assets or (iii) similar relief in respect
of it under any law providing for the relief of debtors, and such proceeding or
case described in clause (i), (ii) or (iii) shall continue undismissed, or
unstayed and in effect, for a period of thirty (30) consecutive days or any
order for relief shall be entered in an involuntary case under the Bankruptcy
Code or under the comparable laws of any jurisdiction (foreign or domestic)
against the Borrower or any of its subsidiaries or action under the laws of any
jurisdiction (foreign or domestic) analogous to any of the foregoing shall be
taken with respect to the Borrower or any of its subsidiaries and shall continue
undismissed, or unstayed and in effect for a period of thirty (30) consecutive
days; or

          h. The occurrence of any event which has a Material Adverse Effect.

     THEN, the Lender may, at its election and without demand or notice of any
kind, which are hereby waived, declare the unpaid balance of the Note, and
accrued interest thereon, immediately due and payable, proceed to collect the
same, and exercise any and all other rights, powers and remedies given it by
this Agreement, the Note and the other Loan Documents or otherwise at law or in
equity.

     7. Miscellaneous.

          a. The representations and warranties of the Borrower contained herein
shall survive the making of the Loan and shall remain effective until all
indebtedness contemplated hereby shall have been paid by the Borrower in full.

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          b. This Agreement shall be governed by and construed in accordance
with the laws of the State of New York without giving effect to the choice of
law provisions. This Agreement shall not be interpreted or construed with any
presumption against the party causing this Agreement to be drafted.

          c. Each of the Borrower and the Lender (i) hereby irrevocably submits
to the jurisdiction of the United States District Court sitting in the Southern
District of New York and the courts of the State of New York located in New York
county for the purposes of any suit, action or proceeding arising out of or
relating to this Agreement or the Loan Documents and (ii) hereby waives, and
agrees not to assert in any such suit, action or proceeding, any claim that it
is not personally subject to the jurisdiction of such court, that the suit,
action or proceeding is brought in an inconvenient forum or that the venue of
the suit, action or proceeding is improper. Each of the Borrower and the Lender
consents to process being served in any such suit, action or proceeding by
mailing a copy thereof to such party at the address set forth in Section 7(j)
below and agrees that such service shall constitute good and sufficient service
of process and notice thereof. Nothing in this Section 7(c) shall affect or
limit any right to serve process in any other manner permitted by law.

          d. Any forbearance, failure, or delay by the Lender in exercising any
right, power, or remedy shall not preclude the further exercise thereof, and all
of the Lender's rights, powers, and remedies shall continue in full force and
effect until specifically waived in writing by the Lender.

          e. This Agreement may be executed in two or more counterparts, all of
which shall be considered one and the same agreement and shall become effective
when counterparts have been signed by each party and delivered to the other
party.

          f. The headings of this Agreement are for convenience of reference and
shall not form part of, or affect the interpretation of, this Agreement.

          g. If any provision of this Agreement shall be invalid or
unenforceable in any jurisdiction, such invalidity or unenforceability shall not
affect the validity or enforceability of the remainder of this Agreement or the
validity or enforceability of this Agreement in any other jurisdiction.

          h. The Borrower shall reimburse the Lender, on demand, for all
reasonable fees and costs incurred by the Lender (including reasonable fees and
costs of the Lender's counsel) in connection with the enforcement of the
Lender's rights and remedies thereunder.

          i. This Agreement and the instruments referenced herein contain the
entire understanding of the parties with respect to the matters covered herein
and therein. No provision of this Agreement may be waived or amended other than
by an instrument in writing signed by the party to be charged with enforcement.

          j. Any notices, demands or waivers required or permitted to be given
under the terms of this Agreement shall be in writing and shall be sent by
certified or registered mail (return receipt requested) or delivered personally
or by courier (including a recognized overnight delivery service) or by
facsimile and shall be effective five (5) days after being placed in the mail,
if mailed, or upon receipt, if delivered personally or by courier, or by
facsimile (if received

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during normal business hours), in each case to the address of the party to
receive such notice, demand or waiver as set forth below:

               If to the Borrower:

                    Speedcom Wireless Corporation
                    7020 Professional Parkway East
                    Sarasota, Florida 34240
                    Attention: Sara Byrne, Secretary
                    Fax No.: (941) 907-2394

               If to the Lender:

                    SDS Merchant Fund, L.P.
                    c/o SDS Capital Partners, LLC
                    53 Forest Avenue, 2nd Floor
                    Old Greenwich, CT 06870
                    Attention: Steve Derby
                    Fax No.: (203) 967-5851

               with a copy to:

                    Jenkens & Gilchrist Parker Chapin LLP
                    The Chrysler Building
                    405 Lexington Avenue
                    New York, New York 10174
                    Attention: Christopher S. Auguste
                    Tel. No.: (212) 704-6000
                    Fax No.: (212) 704-6288

     Each party shall provide notice to the other party of any change in
address, such notice to become effective upon receipt.

          k. This Agreement shall be binding upon and inure to the benefit of
the parties and their successors and assigns. The Borrower shall not assign this
Agreement or any rights or obligations hereunder without the prior written
consent of the Lender. Notwithstanding the foregoing, the Lender may assign its
rights hereunder to any other person or entity without the consent of the
Borrower.

          l. This Agreement is intended for the benefit of the parties hereto
and their respective permitted successors and assigns, and is not for the
benefit of, nor may any provision hereof be enforced by, any other person.

          m. All remedies of the Lender (i) are cumulative and concurrent, (ii)
shall not be exhausted by any exercise thereof, but may be exercised as often as
occasion therefor may occur, and (iii) shall not be construed to be waived or
released by the Lender's delay in exercising, or failure to exercise, them or
any of them at any time it may be entitled to do so.

                            [Signature Page Follows]

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     By executing the appropriate signature line below, the Borrower, intending
to be legally bound hereby, agrees to the terms and conditions of this Agreement
as of the date hereof.

                                              Very truly yours,

                                              SDS MERCHANT FUND, L.P.


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


SPEEDCOM WIRELESS CORPORATION


By:
    ------------------------------
    Name: Michael Sternberg
    Title: Chief Executive Officer

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                                    Exhibit A
                                  Form of Note

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                                    Exhibit B
                           Form of Security Agreement

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