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                                                                  "EXHIBIT 10.1"


                               EIGHTH AMENDMENT TO
                           LOAN AND SECURITY AGREEMENT


This Amendment is made effective as of the 9th day of April, 2003, by and among
HEI, Inc., a Minnesota corporation ("HEI"), Cross Technology, Inc., a Minnesota
corporation ("Cross" and, together with HEI, the "Borrower"), and LaSalle
Business Credit, LLC, a Delaware limited liability company successor by merger
to LaSalle Business Credit, Inc., a Delaware corporation (the "Lender").

                                    Recitals

HEI and the Lender have entered into that certain Loan and Security Agreement
dated as of July 31, 2000, as amended (collectively, the "Loan Agreement") to
which Cross is also a party as a Borrower.

HEI may request certain advances from the Lender from time to time pursuant to
the Loan Agreement, and the Lender has previously made capital expenditure
loans, term loans, machinery and equipment loans, and has made available letters
of credit, to or for the benefit of HEI pursuant to the terms of the Loan
Agreement.

The revolving loan advances under the Loan Agreement are evidenced by HEI's
amended and restated revolving note dated December 1, 2002, in the maximum
principal amount of $3,000,000 and payable to the order of the Lender (the
"Revolving Note"). The capital expenditure loans and term loans made under the
Loan Agreement have been repaid in full.

All indebtedness of HEI to the Lender is secured pursuant to the terms of the
Loan Agreement and all Other Agreements as defined therein.

NOW, THEREFORE, in consideration of the premises and of the mutual covenants and
agreements herein contained, it is agreed as follows:

1. Terms used in this Amendment which are defined in the Loan Agreement shall
have the same meanings as defined therein, unless otherwise defined herein.

2. The Loan Agreement is hereby amended as follows:

     (a)  Section 14(n)(iv) of the Loan Agreement is hereby amended by deleting
          said Section in its entirety and replacing the same with the
          following:

          "(iv) Liabilities to Tangible Net Worth Ratio. Borrower shall
          maintain, on an aggregate basis with all Subsidiaries of Borrower, a
          ratio of (A) Liabilities (provided, however, that for purposes of this
          Section 14(n)(iv),

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          Liabilities shall include amounts owed to LaSalle, its parents,
          affiliates or subsidiaries, or any other Person), other than
          subordinated debt, to (B) Tangible Net Worth, as of the end of each
          fiscal quarter, of not less than 0.75 to 1.0."

3. The Borrower has provided the Lender with certain information indicating a
violation by the Borrower of the covenant set forth at Section 14(n)(iv) of the
Loan Agreement relating to Year to Date Net Loss, with respect to the Borrower's
fiscal quarter ended March 1, 2003, and has requested that the Lender waive such
violation. The Borrower's violation of the covenant set forth in Section
14(n)(iv) described above constitutes an Event of Default under the Loan
Agreement, absent an appropriate waiver. The Lender hereby waives the Event of
Default, which is the result of the covenant violation specifically described
above. Except for the specific waiver set forth in the immediately preceding
sentence, the Lender is not waiving any Default, Event of Default, covenant,
violation, or breach of the Loan Agreement or any of the Other Agreements,
whether or not known to the Lender and whether or not existing on the date
hereof or any other event, circumstance or condition which with the giving of
notice or the passage of time, or both, would constitute a Default, Event of
Default, violation or breach of the Loan Agreement or any of the Other
Agreements. Lender specifically reserves the right to exercise any and all
rights and remedies available to it under the Loan Agreement and the documents
related thereto in the event of a Default or an Event of Default at any time in
the future. Without limiting the foregoing, Lender expects that the Borrower
will maintain compliance with all its covenants under and relating to the Loan
Agreement, including the covenant regarding Tangible Net Worth, [Jim, do we
still need all the following covenants in this sections if they no longer
apply?]the covenant regarding Interest Coverage Ratio, the covenant regarding
Debt Service Coverage Ratio and the newly effective covenant relating to the
ratio of Liabilities to Tangible Net Worth, and Lender will closely monitor the
same in the future to ascertain such continued compliance. The failure or
forbearance by Lender to exercise any of its rights or remedies at any time
shall not constitute a waiver of any such rights or remedies.

4. The Lender has been informed of the acquisition by HEI, Inc. of certain
assets (the "Acquisition") pursuant to that certain Asset Purchase Agreement
dated January 24, 2003 by and between HEI, Inc. and Colorado MEDtech, Inc. (the
"Purchase Agreement"). The Lender hereby consents to the Acquisition, in
accordance with and pursuant to the Purchase Agreement.

5. The Borrower hereby agrees to exercise commercially reasonable efforts to
obtain sufficient alternative financing (debt, equity or otherwise) to enable
the Borrower to prepay all of the Loans in full, and to terminate the Loan
Agreement on or before June 30, 2003 (the "Target Date"). The Borrower hereby
agrees to pay to the Lender on July 1, 2003, a fully-earned, non-refundable
accommodation fee in the amount of $50,000.00, if all Loans are not paid in full
and the Loan Agreement is not terminated on or before the Target Date.

6. Except as otherwise provided in this Amendment, all of the terms and
conditions of the Loan Agreement shall remain in full force and effect and shall
apply to any advance thereunder.

7. This Amendment shall be effective as of the date hereof, upon receipt by the
Lender of (1) an executed original hereof, together with such resolutions and
other documents, instruments



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and agreements as the Lender may require, and (2) a fully-earned,
non-refundable amendment fee in an amount equal to $25,000.

8. The Borrower hereby represents and warrants to the Lender as follows:

     (a)  The Borrower has requisite power and authority to execute this
          Amendment and to perform all of its obligations hereunder, and this
          Amendment has been duly executed and delivered by the Borrower and
          constitutes the legal, valid and binding obligation of the Borrower,
          enforceable in accordance with its terms.

     (b)  The execution, delivery and performance by the Borrower of this
          Amendment have been duly authorized by all necessary corporate action
          and do not (i) require any authorization, consent or approval by any
          governmental department, commission, board, bureau, agency or
          instrumentality, domestic or foreign, (ii) violate any provision of
          any law, rule or regulation or of any order, writ, injunction or
          decree presently in effect, having applicability to the Borrower, or
          the articles of incorporation or by-laws of the Borrower, or (iii)
          result in a breach of or constitute a default under any indenture or
          loan Agreement or any other agreement, lease or instrument to which
          the Borrower is a party or by which it or its properties may be bound
          or affected, except that the consent of U.S. Bank National Association
          ("US Bank") is required under the Business Loan Agreement dated May
          24, 1999 with US Bank (the "US Bank Agreement") for any additional
          indebtedness incurred after the date of the US Bank Agreement.

     (c)  All of the representations and warranties contained in paragraph 13 of
          the Loan Agreement are correct on and as of the date hereof as though
          made on and as of such date, except to the extent that such
          representations and warranties relate solely to an earlier date, and
          except to the extent that such representations and warranties are
          incorrect as a result of a failure to obtain the above-described
          consent under the US Bank Agreement.

9. All references in the Loan Agreement to "this Agreement" shall be deemed to
refer to the Loan Agreement as amended hereby; and any and all references in the
Other Agreements to the Loan Agreement shall be deemed to refer to the Loan
Agreement as amended hereby.

10. The Borrower hereby absolutely and unconditionally releases and forever
discharges the Lender, and any and all participants, parent corporations,
subsidiary corporations, affiliated corporations, insurers, indemnitors,
successors and assigns thereof, together with all of the present and former
directors, officers, agents and employees of any of the foregoing, from any and
all claims, demands or causes of action of any kind, nature or description,
whether arising in law or equity or upon contract or tort or under any state or
federal law or otherwise, which the Borrower has had, now has or has made claim
to have against any such person for or by reason of any act, omission, matter,
cause or thing whatsoever arising from the beginning of time to and including
the date of this Amendment, whether such claims, demands and causes of action
are matured or unmatured or known or unknown.



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11. The Borrower hereby reaffirms its agreement under the Loan Agreement to pay
or reimburse the Lender on demand for all costs and expenses incurred by the
Lender in connection with the Loan Agreement, the Other Agreements and all other
documents contemplated thereby, including without limitation all reasonable fees
and disbursements of legal counsel. Without limiting the generality of the
foregoing, the Borrower specifically agrees to pay all fees and disbursements of
counsel to the Lender, for the services performed by such counsel in connection
with the preparation of this Amendment and the documents and instruments
incidental hereto. The Borrower hereby agrees that the Lender may, at any time
or from time to time in its sole discretion and without further authorization by
the Borrower, make a loan to the Borrower under the Loan Agreement, or apply the
proceeds of any loan, for the purpose of paying any such fees, disbursements,
costs and expenses.

12. This Amendment may be executed in any number of counterparts, each of which
when so executed and delivered shall be deemed an original and all of which
counterparts, taken together, shall constitute one and the same instrument.

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly
executed effective as of the day and year first above written.

                                      HEI, INC.


                                      By:
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                                      Its:
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                                      CROSS TECHNOLOGY, INC.


                                      By:
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                                      Its:
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                                      LASALLE BUSINESS CREDIT, LLC


                                      By:
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                                      Its:
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