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                                                                   EXHIBIT 10.11


                       SIXTH AMENDMENT TO CREDIT AGREEMENT

         This Amendment ("Amendment") is made as of the 30th day of June, 2000,
by and between Electronic Tele-Communications, Inc. (the "Borrower") and Bank
One, Wisconsin (the "Lender").

         WHEREAS, the Borrower and the Lender entered into a Credit Agreement
dated May 17, 1989, as amended (the "Credit Agreement"); and

         WHEREAS, the parties hereto desire to amend the Credit Agreement as set
forth below:

         NOW, THEREFORE, the parties hereto agree as follows:

         1.       Capitalized terms not defined herein shall have the meaning
                  ascribed in the Credit Agreement.

         2.       Amendments. The Credit Agreement is amended as follows:

                  2.1      Section 1.15 is hereby amended by deleting "June 30,
                           2000" and inserting "June 30, 2003" in its place.

                  2.2      Section 2.2 is hereby amended by deleting "$25,000"
                           and inserting "$100,000.00" in its place.

                  2.3      Section 2.6 (a) is hereby amended by deleting "an
                           annual rate equal to the Reference Rate" and
                           inserting "an annual rate equal to the Reference Rate
                           -.50% " in its place.

                  2.4      Section 2.6 (b) is hereby amended by deleting "plus
                           two percentage points" and inserting "plus 1.85%" in
                           its place.

                  2.5      Section 6.8 is hereby amended and restated to read as
                           follows:

                           Permit the minimum Consolidated Tangible Net Worth,
                           at all times, to be less than $4,787,000.00.

                  2.6      Section 6.12 is hereby amended by deleting "15%" and
                           inserting "12.50%" in its place.

         3. The Borrower represents and warrants that (a) the representations
and warranties contained in the Credit Agreement are true and correct in all
material respects as of the date of this Amendment, (b) no condition, act or
event which could constitute an Event of Default under the Credit Agreement
exists, and (c) no condition, event, act or omission has occurred, which, with
the giving of notice or passage of time, would constitute an Event of Default
under the Credit Agreement.

         4. The Borrower agrees to pay all fees and out-of-pocket disbursements
incurred by the Lender in connection with this Amendment, including legal fees
incurred by the Lender in the preparation, consummation, administration and
enforcement of this Amendment.

         5. This Amendment shall become effective only after it is fully
executed by the Borrower and the Lender. Except as amended by this Amendment,
the Credit Agreement shall remain in full force and effect in accordance with
its terms.


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         6. This Amendment is a modification only and not a novation. Except for
the above-quoted modification(s), the Credit Agreement, any agreement or
security document, and all the terms and conditions thereof, shall be and remain
in full force and effect with the changes herein deemed to be incorporated
therein. This Amendment is to be considered attached to the Credit Agreement and
made a part thereof. This Amendment shall not release or affect the liability of
any guarantor, surety or endorser of the Credit Agreement or release any owner
of collateral securing the Credit Agreement. The validity, priority and
enforceability of the Credit Agreement shall not be impaired hereby. To the
extent that any provision of this Amendment conflicts with any term or condition
set forth in the Credit Agreement, or any agreement or security document
executed in conjunction therewith, the provisions of this Amendment shall
supersede and control. Borrower acknowledges that as of the date of this
Amendment it has no offsets with respect to all amounts owed by Borrower to
Lender and Borrower waives and releases all claims which it may have against
Lender arising under the Credit Agreement on or prior to the date of this
Amendment.

         7. The Borrower acknowledges and agrees that this Amendment is limited
to the terms outlined above, and shall not be construed as an amendment of any
other terms or provisions of the Credit Agreement; The Borrower hereby
specifically ratifies and affirms the terms and provisions of the Credit
Agreement. Borrower releases Lender from any and all claims which may have
arisen, known or unknown, in connection with the Credit Agreement on or prior to
the date hereof. This Amendment shall not establish a course of dealing or be
construed as evidence of any willingness on the Lender's part to grant other or
future amendments, should any be requested.

IN WITNESS WHEREOF, the parties have entered into this Amendment as of the day
and year first above written.

BANK ONE, WISCONSIN                        ELECTRONIC TELE-COMMUNICATIONS, INC.



By: /s/ Terry R. Sutter                    By: /s/ Dean W. Danner
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    Terry R. Sutter, Vice President            Dean W. Danner, President