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                                                                   EXHIBIT 10.12

                      SEVENTH AMENDMENT TO CREDIT AGREEMENT

         This Amendment ("Amendment") is made as of the 14th day of November,
2000, by and between Electronic Tele-Communications, Inc. ("ETC") and Bank One,
Wisconsin (f/k/a Bank One, Milwaukee, National Association, successor by merger
to Bank One, Waukesha) (the "Bank").

         WHEREAS, ETC and the Bank 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.  The following definitions are added to section 1 in the proper
             alphabetical sequence:

               "BORROWING BASE" means the sum of (i) 80% of Qualified
         Accounts, (ii) 25% of Qualified Equipment plus (iii) 50% of Qualified
         Inventory.

               "QUALIFIED ACCOUNTS" means an account owing to ETC (a) which
         arose out of the performance of services by ETC, or from a bona-fide
         sale or lease of goods which have been delivered or shipped to the
         account debtor and for which ETC has genuine invoices, shipping
         documents or receipts; (b) which is not more than 90 days past due the
         original date of the relevant invoice and which original due date is
         not more than 30 days after the earlier of delivery of goods,
         performance of services, date of billing or date of such invoice; (c)
         which is owned by ETC free and clear of all encumbrances and security
         interests, except the first priority, validly perfected security
         interest of the Bank; (d) which is enforceable against the account
         debtor without setoff, credit, allowance or discount, except discount
         for prompt payment, for the amounts shown on certificates furnished by
         ETC to the Bank; (e) which, together with the transactions out of which
         it arose, complies with all applicable laws and regulations; (f) as to
         which ETC has no knowledge of anything which might cause the account
         debtor to be unable to pay the account; (g) as to which the account
         debtor has not disputed his liability or returned or threatened to
         return the goods; (h) the existence and amount of which have been
         certified to the Bank by ETC in the manner specified in Section 5.16;
         (i) by an account debt which is not more than 120 days past due in the
         payment of any other amount owed ETC; (j) by an account debtor other
         than an Affiliate and who is located in the United States;

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         and (k) as to which the Bank has not notified ETC that the account or
         account debtor is unsatisfactory. Any Qualified Account which ceases to
         meet any of the foregoing requirements shall cease to be a Qualified
         Account at such time.

               "QUALIFIED EQUIPMENT" means all goods used or bought of ETC (a)
         which are owned by ETC free and clear of all encumbrances and security
         interests except the first priority, validly perfected security
         interest of the Bank; (b) the existence, location, amount and lower of
         cost or wholesale market value of which have been certified to in a
         manner satisfactory to the Bank by an officer of ETC in the manner
         specified in Section 5.16; (c) which is of good merchantable quality,
         free from any defect and is not obsolete, damaged or unsaleable; and
         (d) as to which the Bank has not notified ETC that the particular type
         or item of equipment is unsatisfactory. Any Qualified Equipment which
         ceases to meet any of the foregoing requirements shall cease to be
         Qualified Equipment at such time.

               "QUALIFIED INVENTORY" means finished goods, work-in-process or
         raw material inventory of ETC (a) which is owned by ETC free and clear
         of all encumbrances and security interests except the first priority,
         validly perfected security interest of the Bank; (b) the existence,
         location, amount and lower of cost or wholesale market value of which
         have been certified to in a manner satisfactory to the Bank by an
         officer of ETC in the manner specified in Section 5.16; (c) which is of
         good merchantable quality, free from any defect and is not obsolete,
         damaged or unsaleable; (d) the creation or production of which was done
         in compliance with the Federal Fair Labor Standards Act and the rules
         and regulations thereunder; and (e) as to which the Bank has not
         notified the ETC that the particular type or item of inventory is
         unsatisfactory. Any Qualified Inventory which ceases to meet any of the
         foregoing requirements shall cease to be Qualified Inventory at such
         time.

         3.    Section 2, the section bearing the heading "The Credit
         Facilities" of the Credit Agreement is hereby amended by inserting the
         following paragraph:

               2.5   BORROWING BASE. The unpaid principal balance of the
               Revolving Note shall never exceed, and ETC shall immediately make
               such payments on the Revolving Note as are necessary in order
               that the outstanding balance of the Revolving Note never exceeds
               the Borrowing Base.

         4.    Section 5, the section bearing the heading "Affirmative
         Covenants" of the Credit Agreement is hereby amended by inserting the
         following covenant:

               5.16   BORROWING BASE CERTIFICATE. Furnish to Lender within 30
               days after the end of each month, a

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               borrowing base certificate, in form and detail satisfactory to
               Bank, along with such supporting documentation as Bank may
               request, including without limitation, an accounts receivable
               aging report and/or list or schedule of ETC's accounts
               receivable, equipment and inventory.

         5.    ETC 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.

         6.    ETC agrees to pay all fees and out-of-pocket disbursements
incurred by the Bank in connection with this Amendment, including legal fees
incurred by the Bank in the preparation, consummation, administration and
enforcement of this Amendment.

         7.    This Amendment shall become effective only after it is fully
executed by ETC and the Bank and the Bank shall have received from ETC the fully
executed Waiver Letter dated November 14, 2000, regarding the September 30, 2000
violation of section 6.8 of the Credit Agreement. Except as amended by this
Amendment, the Credit Agreement shall remain in full force and effect in
accordance with its terms.

         8.    This Amendment is a modification only and not a novation. Except
for the above-quoted modifications, 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. ETC acknowledges that as of the date of this Amendment it
has no offsets with respect to all amounts owed by ETC to Bank and ETC waives
and releases all claims which it may have against Bank arising under the Credit
Agreement on or prior to the date of this Amendment.

         9.    ETC 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; ETC hereby specifically ratifies
and affirms the terms and provisions of the Credit Agreement. ETC releases Bank
from


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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 Bank'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
     --------------------------              -----------------------------
     Terry R. Sutter                         Dean W. Danner
     Vice President                          President