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                             ARTICLES OF INCORPORATION           Exhibit 3.27.1

                                       OF

                                  COLTECH, INC.

         The undersigned natural person of the age of 18 years or more does
hereby adopt the following Articles of Incorporation for such corporation:

                                    ARTICLE I.
                                      NAME

         The name of this corporation is COLTECH, INC.

                                    ARTICLE II.
                                     DURATION

         The period of its duration shall be perpetual.

                                    ARTICLE III.
                                PURPOSE OR PURPOSES

         The purpose or purposes for which this corporation is organized are:

         (a)   To conduct a communications manufacturing, and consultant
business;

         (b)   To purchase, receive by way of gift, subscribe for, invest in,
and in all other ways acquire, import, lease, possess, maintain, handle on
consignment, own, hold for investment or otherwise use, enjoy, exercise,
operate, manage, conduct, perform, make, borrow, contract in respect of,
trade and deal in, sell, exchange, let, lend, export, mortgage, pledge, deed
in trust, hypothecate, encumber, transfer, assign, and in all other ways
dispose of, design, develop, invent, improve, equip, repair, alter,
fabricate, assemble, build, construct, operate, manufacture, plant,
cultivate, produce, market, and in all other ways (whether like or unlike any
of the foregoing), deal in and with property of every kind and character,
real, personal, or mixed, tangible or intangible, wherever situated and
however held, including, but not limited to, money, credits, chooses in
action, securities, stocks, bonds, warrants, script, certificates,
debentures, mortgages, notes, commercial paper, and other obligations and
evidences of indebtedness of any government or subdivision or agency thereof,
documents of title, and accompanying rights, and every other kind and
character of personal property, real property (improved or unimproved), and
the products and avails thereof, and every character of interest therein and
appurtenance thereto, including, but not limited thereto, mineral, oil, gas
and water rights, all or any part of any going business and its incidents,
franchises, subsidies, charters, concessions, grants, rights, powers, or
privileges, granted or conferred by any government or subdivision or agency
thereof, and any interest in respect thereof all of the powers, rights,
privileges, and immunities of individual owners or holders thereof;

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         (c)  To hire and employ agents, servants, and employees, to enter
into agreements of employment and collective bargaining agreements, and to
act as agent, contractor, factor, or otherwise, either alone or in company To
hire and with others;

         (d)  To promote or aid in any manner, financially or otherwise, any
person, firm, association, or corporation;

         (e)  (i) To let concessions to others to do any of the things that
this corporation is empowered to do, and to enter into, make, perform, and
carry out, contracts and arrangements of every kind and character with any
person, firm, association, or corporation, or any government or authority or
subdivision or agency thereof;

         (e)  (ii) This corporation cannot act as a trustee in any capacity;

         (e)  (iii) This corporation does not have a primary purpose for the
ownership of land but it shall have the secondary purpose for the ownership
of land-to,be used in connection with its business operation;

         (f)  To carry on any business whatsoever that this corporation may
deem proper or convenient in connection with any of the foregoing purposes or
otherwise, or that it may deem calculated, directly or indirectly, to improve
the interests of this corporation, and to have and to exercise all powers
conferred by the laws of the State of Texas on corporations formed under the
laws pursuant to which and under which this corporation is formed, as such
laws are now in effect or may at any time hereafter be amended, and to do any
and all things hereinabove set forth to the same extent and as fully as
natural persons might do or could do, either alone or in connection with
other persons, firms. associations, or corporations, and in any part of the
world.

         The foregoing statement of purposes shall be construed as a
statement of both purposes and powers, shall be liberally construed in aid of
the powers of this corporation, and the powers and purposes stated in each
clause shall, except where otherwise stated, he in nowise limited or
restricted by any term or provision of any other clause, and shall be
regarded not only as independent purposes, but the purposes and powers stated
shall be construed distributively as each object expressed, and the
enumeration as to specific powers shall not be construed as to limit in any
manner the aforesaid general powers, but are in furtherance of, and in
addition to and not in limitation of said gcneral powers.

                              ARTICLE IV.
                            CAPITALIZATION

         This corporation is authorized to issue only one class of shares of
stock. The total number of shares that this corporation is authorized to
issue is one thousand (1,000) shares of common stock. The aggregate par value
of the shares is One Thousand Dollars ($1,000.00) and the par value of each
share is Ten Cents ($.10). No distinction shall exist between the shares or
between the shareholders thereof.

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                                   ARTICLE V.
                               ISSUANCE OF SHARES

         This corporation will not commence business until it has received
for the issuance of its shares consideration of the value of One Thousand
Dollars ($1,000.00), consisting of money, labor done, or property actually
received, which sum is not less than One Thousand Dollars ($1,000.00).

                                  ARTICLE VI.
                               REGISTERED OFFICE

         The post office address of its initial registered office is 6202
Pineview Rd., Dallas, Texas 75248 and the name of its initial registered
agent at such address is COLE E. CUNNINGHAM.

                                  ARTICLE VII.
                                    DIRECTORS

         (a) The number of Director constituting the intial Board of
Directors is two, and the names and addresses of the persons who are to serve
as Directors until the first annual meeting of the shareholders or until
their successors are elected and qualified are:

         NAME:                                 ADDRESS:

         Cole E. Cunningham                    6202 Pineview Rd.
                                               Dallas, Texas 75248

         Joan L. Cunningham                    6202 Pineview Rd.
                                               Dallas, Texas 75248

         (b)  The number of Directors of this corporation set forth in clause
(a) of this Article VII, shall constitute the authorized number of Directors
until changed by an amendment of a bylaw duly adopted by the vote or written
consent of the holders of a majority of the then outstanding shares of stock
of this corporation.

                               ARTICLE VIII.
                               INCORPORATOR

         The name and address of the incorporator is:

         NAME:                                 ADDRESS:

         Ronald L. Hendricks                   1605 Cross Bend Road

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         IN WITNESS WHEREOF, for the purpose of forming this corporation
under the laws of the State of Texas, I, the undersigned, constituting the
incorporator of this corporation, have executed these Articles of
Incorporation this 14th day of May, 1982.

                                        /S/ RONALD L. HENDRICKS
                                        -------------------------------
                                        INCORPORATOR


STATE OF TEXAS

COUNTY OF DALLAS

         I, Nancy Moore, Notary Public, do hereby certify that on this 14th day
of May, 1982, personally appeared before me Ronald L. Hendricks, who being by me
sworn, declared that he is person who signed the foregoing document as the
incorporator, and that the statements made therein contained are true.


                                        /S/ NANCY MOORE
                                        -------------------------------
                                        NANCY MOORE, Notary Public
                                        in and for Dollas County, Texas


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