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                                                                    EXHIBIT 4.18

             SECOND AMENDMENT TO CANADIAN REVOLVING CREDIT AGREEMENT

      THIS SECOND AMENDMENT TO CANADIAN REVOLVING CREDIT AGREEMENT dated as of
June 24, 2005 (this "AMENDMENT") by and among EMS TECHNOLOGIES CANADA, LTD., a
corporation incorporated under the laws of Canada (the "BORROWER"), EMS
TECHNOLOGIES, INC., a Georgia corporation (the "PARENT"), the Lenders listed on
the signature pages hereof and BANK OF AMERICA, NATIONAL ASSOCIATION (CANADA
BRANCH), as Canadian Administrative Agent (the "AGENT").

      WHEREAS, the Borrower, EMS, the Lenders and the Agent are parties to that
certain Canadian Revolving Credit Agreement dated as of December 10, 2004, as
amended by an amending agreement dated as of February 11, 2005 (the "CREDIT
AGREEMENT"); and

      WHEREAS, the Borrower, the Lenders and the Agent desire to amend the
Credit Agreement in certain respects on the terms and conditions contained
herein;

      NOW THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged by the parties hereto, the parties
hereto hereby agree as follows:

      Section 1. Amendments to Definitions in Credit Agreement.

Section 1.1 of the Credit Agreement is hereby amended by deleting the defined
term "LETTER OF CREDIT", and substituting in lieu thereof the following:

            "`LETTER OF CREDIT' shall mean any standby letter of credit or
      documentary letter of credit issued pursuant to Section 2.22 by the
      Issuing Bank for the account of the Borrower pursuant to the LC
      Commitment."

      Section 2. Amendments to Letter of Credit Provision Terms.

      (a) The Credit Agreement is hereby amended by deleting Section 2.22(a)
thereof in its entirety and substituting the following therefor: "

            "(a) During the Availability Period, the Issuing Bank, in reliance
            upon the agreements of the other Lenders pursuant to Section
            2.22(d), agrees to issue, at the request of the Borrower, Letters of
            Credit for the account of the Borrower on the terms and conditions
            hereinafter set forth; provided, that (i) each Letter of Credit
            shall be a standby letter of credit or a documentary letter of
            credit which shall expire, in the case of a standby letter of credit
            no later than the date that is three years (or such later date
            agreed by the Issuing Bank) after the date of issuance of such
            Letter of Credit (or in the case of any renewal or extension
            thereof, one year after such renewal or extension), or in the case
            of a documentary letter of credit 180 days (or such later date
            agreed by the Issuing Bank) after the issuance of such Letter of
            Credit, provided that if, in either case, the date of expiry is a
            date that is beyond five Business Days prior to the Commitment
            Termination

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            Date, the provisions of Section 2.22(g) shall apply; (ii) each
            Letter of Credit shall be in such currencies as the Issuing Lender
            will from time to time permit in a stated amount of at least the
            Canadian Dollar Equivalent of $50,000 (or such other amounts as
            agreed with the Issuing Bank); and (iii) the Borrower may not
            request any Letter of Credit, if, after giving effect to such
            issuance (A) the aggregate LC Exposure would exceed the LC
            Commitment or (B) thereafter the aggregate LC Exposure, plus the
            aggregate outstanding Swingline Loans, plus the aggregate
            outstanding Revolving Loans of all Lenders would exceed
            U.S.$32,500,000. Upon the issuance of each Letter of Credit, each
            Lender shall be deemed to, and hereby irrevocably and
            unconditionally agrees to, purchase from the Issuing Bank without
            recourse a participation in such Letter of Credit equal to such
            Lender's Pro Rata Share of the aggregate amount available to be
            drawn under such Letter of Credit. Each issuance of a Letter of
            Credit shall be deemed to utilize the Revolving Commitment of each
            Lender by an amount equal to the amount of such participation."

      (b) The Credit Agreement is hereby amended by deleting Section 2.22(g)
thereof in its entirety and substituting the following therefor:

            "(g) If either (i) any Event of Default shall occur and be
            continuing, on the Business Day that the Borrower receives notice
            from the Funding Agent or the Required Lenders demanding the deposit
            of cash collateral pursuant to this paragraph, or (ii) if Letters of
            Credit have been issued pursuant to Section 2.22(a) with expiry
            dates beyond five Business days prior to the Commitment Termination
            Date, then not later than 30 days prior to the Commitment
            Termination Date, the Borrower shall deposit in an account with the
            Funding Agent, in the name of the Funding Agent and for the benefit
            of the Lenders, an amount in cash equal to 105% of the LC Exposure
            as of such date plus any accrued and unpaid interest thereon;
            provided, that the obligation to deposit such cash collateral shall
            become effective immediately, and such deposit shall become
            immediately due and payable, without demand or notice of any kind,
            upon the occurrence of any Event of Default with respect to the
            Borrower described in subsection (g) or (h) of Section 8.1. Such
            deposit shall be held by the Funding Agent as collateral in an
            interest-bearing account (which account shall be chosen in the
            reasonable discretion of the Funding Agent and at the Borrower's
            risk and expense) for the payment and performance of the obligations
            of the Borrower under this Agreement. The Funding Agent shall have
            exclusive dominion and control, including the exclusive right of
            withdrawal, over such account. Interest and profits on such
            investments shall accumulate in such account. Moneys in such account
            shall be applied by the Funding Agent to reimburse the Issuing Bank
            for LC Disbursements for which it had not been reimbursed and to the
            extent not so applied, shall be held for the satisfaction of the
            reimbursement obligations of the Borrower for the LC Exposure at
            such time or, if the maturity of the Loans has been accelerated,
            with the consent of the Required Lenders, be applied to satisfy
            other obligations of the Borrower under this Agreement. If the
            Borrower is required to provide an amount of cash collateral
            hereunder as a result of the occurrence of an Event of Default, such
            amount (to the extent not so applied as

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            aforesaid) shall be returned to the Borrower within three Business
            Days after all Events of Default have been cured or waived."

      (c) The Credit Agreement is hereby amended by adding the following
provision as a new Section 2.22(j):

            "(j) The Issuing Bank shall not be under any obligation to issue any
            Letter of Credit if any order, judgment or decree of any
            Governmental Authority or arbitrator shall by its terms purport to
            enjoin or restrain the Issuing Bank from issuing such Letter of
            Credit, or any Applicable Law or any request or directive (whether
            or not having the force of law) from any Governmental Authority with
            jurisdiction over the Issuing Bank shall prohibit, or request that
            the Issuing Bank refrain from, the issuance of letters of credit
            generally or such Letter of Credit in particular or shall impose
            upon the Issuing Bank with respect to such Letter of Credit any
            restriction, reserve or capital requirement (for which the Issuing
            Bank is not otherwise compensated hereunder) not in effect on the
            Closing Date, or shall impose upon the Issuing Bank any unreimbursed
            loss, cost or expense which was not applicable on the Closing Date
            and which the Issuing Bank in good faith deems material to it, or if
            the issuance of such Letter of Credit would violate one or more
            policies of the Issuing Bank"

      (d) The Credit Agreement is hereby amended by deleting the last paragraph
of Section 2.22 thereof in its entirety and substituting the following therefor:

            Unless otherwise expressly agreed by the Issuing Bank and the
            Borrower when a Letter of Credit is issued and subject to applicable
            laws, performance under Letters of Credit by the Issuing Bank, its
            correspondents, and the beneficiaries thereof will be governed, in
            the case of standby letters of credit, by the rules of the
            "International Standby Practices 1998" (ISP98) (or such later
            revision as may be published by the Institute of International
            Banking Law & Practice on any date any Letter of Credit may be
            issued) and in the case of documentary letters of credit by the
            rules of the "ICC Uniform Customs and Practice for Documentary
            Credits UCP 500" and in each case to the extent not inconsistent
            therewith, the governing law of this Agreement set forth in Section
            10.5.

      Section 3. Effectiveness of Amendment. The effectiveness of this Amendment
is subject to the truth and accuracy of the representations set forth in Section
4 and Section 5 below and receipt by the Agent of each of the following, each of
which shall be in form and substance satisfactory to the Agent:

      (a) Counterparts of this Amendment duly executed by the Borrower, each
Guarantor, the Agent and the Lenders; and

      (b) Such other documents, agreements, instruments, certificates or other
confirmations as the Agent may request.

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      Section 4. Representations of the Borrower. The Borrower represents and
warrants to the Agent and the Lenders that:

      (a) Corporate Power and Authority. The Borrower has the corporate power
and authority to execute, deliver and perform the terms and provisions of the
Credit Agreement, as amended by this Amendment, and has taken all necessary
corporate action to authorize the execution, delivery and performance by it of
this Amendment. The Borrower has duly executed and delivered this Amendment, and
this Amendment constitutes its legal, valid and binding obligation enforceable
in accordance with its terms, except to the extent that the enforceability
thereof may be limited by applicable bankruptcy, insolvency, reorganization,
moratorium or other similar laws generally affecting creditors' rights and by
equitable principles (regardless of whether enforcement is sought in equity or
at law).

      (b) No Violation. The execution, delivery or performance by the Borrower,
and compliance by the Borrower with the terms and provisions of this Amendment
(i) will not contravene any provision of any law, statute, rule or regulation or
any order, writ, injunction or decree of any court or Governmental Authority,
(ii) will not conflict with or result in any breach of any of the terms,
covenants, conditions or provisions of, or constitute a default under, or result
in the creation or imposition of (or the obligation to create or impose) any
Lien upon any of the property or assets of the Borrower or any of its
Subsidiaries pursuant to the terms of any indenture, mortgage, deed of trust,
credit agreement or loan agreement, or any other agreement, contract or
instrument, to which the Borrower or any of its Subsidiaries is a party or by
which it or any of its property or assets is bound or to which it may be subject
or (iii) will not violate any provision of the certificate or articles of
incorporation or by-laws (or equivalent organizational documents) of the
Borrower or any of its Subsidiaries.

      (c) Governmental Approvals. No order, consent, approval, license,
authorization or validation of, or filing, recording or registration with
(except for those that have otherwise been obtained or made on or prior to the
date of the effectiveness of this Amendment and which remain in full force and
effect on such date), or exemption by, any Governmental Authority, is required
to authorize, or is required in connection with, (i) the execution, delivery and
performance of this Amendment by the Borrower or any Subsidiary Loan Party or
(ii) the legality, validity, binding effect or enforceability of this Amendment
against the Borrower or any Subsidiary Loan Party.

      (d) No Default. No Default or Event of Default now exists or will exist
immediately after giving effect to this Amendment.

      Section 5. Reaffirmation of Representations. The Borrower hereby repeats
and reaffirms all representations and warranties made by it to the Agent and the
Lenders in the Credit Agreement and the other Loan Documents to which it is a
party on and as of the date hereof (and after giving effect to this Amendment)
with the same force and effect as if such representations and warranties were
set forth in this Amendment in full (except to the extent of changes resulting
from transactions contemplated or permitted by the Credit Agreement and to the
extent that such representations and warranties relate expressly to an earlier
date).

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      Section 6. References to the Credit Agreement. Each reference to the
Credit Agreement in any of the Loan Documents (including the Credit Agreement)
shall be deemed to be a reference to the Credit Agreement, as amended by this
Amendment.

      Section 7. Benefits. This Amendment shall be binding upon and shall inure
to the benefit of the parties hereto and their respective permitted successors
and assigns.

      Section 8. Expenses. The Borrower agrees to reimburse the Lenders and the
Agent on demand for all reasonable costs and expenses (including, without
limitation, attorneys' fees) incurred by such parties in negotiating,
documenting and consummating this Amendment, the other documents referred to
herein, and the transactions contemplated hereby and thereby.

      Section 9. GOVERNING LAW. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF
THE PARTIES HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE
LAWS OF THE PROVINCE OF ONTARIO AND THE LAWS OF CANADA APPLICABLE THEREIN.

      Section 10. Effect/Loan Document. Except as expressly herein amended, the
terms and conditions of the Credit Agreement and the other Loan Documents shall
remain in full force and effect. This Amendment shall be deemed to be a "Loan
Document" for all purposes under the Credit Agreement. The amendments herein
will apply to all currently issued and outstanding Letters of Credit, including
any renewals or extensions thereof.

      Section 11. Counterparts. This Amendment may be executed in any number of
counterparts, each of which shall be deemed to be an original and shall be
binding upon all parties, their successors and assigns.

      Section 12. Definitions. All capitalized terms not otherwise defined
herein are used herein with the respective definitions given them in the Credit
Agreement.

                         [SIGNATURES ON FOLLOWING PAGES]

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      IN WITNESS WHEREOF, the parties hereto have caused this Second Amendment
to Canadian Revolving Credit Agreement to be executed as of the date first above
written.

                                      EMS TECHNOLOGIES CANADA, LTD.

                                      By: ____________________________________
                                           Name:
                                           Title:

                                      EMS TECHNOLOGIES, INC.

                                      By: ____________________________________
                                           Name:
                                           Title:

                                      BANK OF AMERICA, NATIONAL
                                      ASSOCIATION, CANADA BRANCH, as
                                      Canadian Administrative Agent, as Issuing
                                      Bank, as Swingline Lender as a Lender

                                      By: ____________________________________
                                           Name:
                                           Title:

                                      GE CANADA FINANCE HOLDING
                                      COMPANY, in its capacity as a Lender

                                      By: ____________________________________
                                           Name:
                                           Title:

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The following entities hereby execute this Second Amendment to Canadian
Revolving Credit Agreement to indicate their consent thereto and to acknowledge
that the making and entering into of this Canadian Revolving Second Amendment to
Credit Agreement shall not terminate, limit or otherwise impair or affect any of
their respective obligations to the Agent, the Issuing Bank and/or the Lenders
under the Loan Documents.

EMS INVESTMENT HOLDINGS, INC.

By:  _________________________________

    Name:
    Title:

LXE INC.

By:  _________________________________

    Name:
    Title:

990834 ONTARIO INC.

By: __________________________________

    Name:
    Title: