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                                                                    EXHIBIT 10.1

                       SEVENTH AMENDMENT AND FOURTH WAIVER

     SEVENTH AMENDMENT AND FOURTH WAIVER, dated as of April 30, 2002 (this
"Amendment"), to and under the Amended and Restated Credit and Guarantee
Agreement, dated as of July 27, 2000 (as heretofore amended, supplemented or
otherwise modified, the "Credit Agreement"), among SMTC Corporation
("Holdings"), HTM Holdings, Inc. (the "U.S. Borrower"), SMTC Manufacturing
Corporation of Canada (the "Canadian Borrower"; together with the U.S. Borrower,
the "Borrowers"), the several banks and other financial institutions or entities
from time to time parties thereto (the "Lenders"), Lehman Brothers Inc., as
advisor, lead arranger and book manager, The Bank of Nova Scotia, as syndication
agent, Lehman Commercial Paper Inc., as general administrative agent (in such
capacity, the "General Administrative Agent"), The Bank of Nova Scotia, as
Canadian administrative agent, Lehman Commercial Paper Inc., as collateral
monitoring agent, and General Electric Capital Corporation, as documentation
agent.

                              W I T N E S S E T H:
                              - - - - - - - - - -

     WHEREAS, Holdings and the Borrowers requested that the Lenders agree to
amend certain of the provisions of the Credit Agreement upon the terms and
subject to the conditions set forth below; and

     WHEREAS, the Required Lenders have consented to the requested amendments in
the manner set forth below;

     NOW, THEREFORE, in consideration of the premises and the material covenants
herein contained, the parties hereto hereby agree as follows:

     1. Defined Terms. Terms used herein and defined in the Credit Agreement are
used herein as therein defined.

     2. Waiver of Defaults or Events of Default. The Lenders hereby waive the
Defaults and Events of Default arising by reason of (a) the failure of Holdings
and the Borrowers to comply with the provisions of Sections 10.14(c) and (d) of
the Credit Agreement for any period prior to the Effective Date (as defined
below) with respect to the accounts listed on Schedule A hereof, (b) any
representation and warranty made by any Borrower, in connection with any
extension of credit under the Credit Agreement prior to the Effective Date, to
the effect that no Default or Event of Default had occurred by reason of the
failure of Holdings and the Borrowers to comply with the provisions of Sections
10.14(c) and (d) of the Credit Agreement with respect to the accounts listed on
Schedule A hereof or (c) any failure of Holdings or any Borrower to give notice
under the Credit Agreement of the failure of Holdings and the Borrowers to
comply with the provisions of Sections 10.14(c) and (d) of the Credit Agreement
with respect to the accounts listed on Schedule A hereof; provided that the
foregoing waiver is conditioned upon Holdings and the Borrowers being in
compliance with Sections 10.14(c) and (d) of the Credit Agreement on or before
May 10, 2002.

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     3. Amendment to Section 11.1(f) to the Credit Agreement (Maximum
Outstanding Extensions of Credit). Section 11.1(f) is hereby amended by:

          (a) amending paragraph (i) thereof by deleting each reference therein
     to "Schedule 11.1(f)" and inserting in lieu thereof a reference to
     "Schedule 11.1(f)(i)";

          (b) amending paragraph (ii) thereof by deleting such paragraph in its
     entirety and inserting in lieu thereof the following:

               "(ii) On any day (other than the last day) of any month set forth
          on Schedule 11.1(f)(ii), permit the Total Revolving Extensions of
          Credit to exceed the lesser of (A) the Borrowing Base in effect on
          such day and (B) the amount set forth on Schedule 11.1(f)(ii) for the
          last day of such month."; and

          (c) amending paragraph (iii) thereof by adding at the end of clause
     (A) therein immediately before the comma therein "(other than any such
     Event of Default that has been waived (whether by waiver under or amendment
     to this Agreement) by the Lenders pursuant to Section 15.1)".

     4. Amendment to Section 11.1(g) of the Credit Agreement (Minimum
Availability Test). Section 11.1(g) of the Credit Agreement is hereby amended by
deleting "$20,000,000" therein and inserting in lieu thereof "the amount set
forth opposite the last day of such month on Schedule 11.1(g)".

     5. Amendment to Section 11.8 of the Credit Agreement (Limitation on
Investments). Section 11.8(n) of the Credit Agreement is hereby amended by
adding at the end thereof the following: "provided that no additional loans
shall be permitted pursuant to this clause (n) on and after April 30, 2002;".

     6. Amendment to Section 11.10 of the Credit Agreement (Limitation on
Transactions with Affiliates). Section 11.10 of the Credit Agreement is hereby
amended by deleting clause (viii) in the second sentence thereof and
substituting in lieu thereof the following: "(viii) payments for services
rendered or loans to employees or consultants which are approved by the Board of
Directors of Holdings in good faith, provided that no additional loans shall be
permitted pursuant to this clause (viii) on and after April 30, 2002,".

     7. Amendment to Schedule 11.1(e) to the Credit Agreement (Minimum
Cumulative Consolidated EBITDA). Schedule 11.1(e) to the Credit Agreement is
hereby amended by replacing such schedule in its entirety with a new Schedule
11.1(e) in the form attached to this Amendment as Annex A.

     8. Amendment to Schedule 11.1(f) to the Credit Agreement (Maximum
Outstanding Extensions of Credit). Schedule 11.1(f) to the Credit Agreement is
hereby deleted in its entirety.

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     9. Addition of New Schedules to the Credit Agreement. The Credit Agreement
is hereby amended by adding Schedules 11.1(f)(i), 11.1(f)(ii) and 11.1(g)
thereto in the forms attached to this Amendment as Annexes B, C and D,
respectively.

     10. Effectiveness. This Amendment shall become effective on the date of
satisfaction of the following conditions precedent (the "Effective Date"):

          (a) The General Administrative Agent shall have received counterparts
     of this Amendment, duly executed and delivered by Holdings and each of the
     Borrowers.

          (b) The General Administrative Agent shall have received executed
     Lender Consent Letters, substantially in the form of Exhibit A hereto
     ("Lender Consent Letters"), from Lenders constituting the Required Lenders.

          (c) The General Administrative Agent shall have received an executed
     Acknowledgment and Consent (i) in the form set forth at the end of this
     Amendment, from each Loan Party other than the Borrowers and any Loan Party
     party to the Canadian Facility Guarantees (the "Canadian Guarantors") and
     (ii) in form and substance reasonably satisfactory to the Canadian
     Administrative Agent, from each Canadian Guarantor.

          (d) Holdings and the Warrant Agent (as defined in the Warrant
     Agreement) shall have executed and delivered an amendment to the Warrant
     Agreement in the form attached hereto as Annex E and the Warrants required
     to have been issued pursuant to such amendment on the Effective Date shall
     have been issued (whether or not certificates therefor have been
     delivered).

          (e) All corporate and other proceedings, and all documents,
     instruments and other legal matters in connection with the transactions
     contemplated by this Amendment shall be satisfactory in form and substance
     to the General Administrative Agent.

          (f) The Lenders and the General Administrative Agent shall have
     received all fees required to be paid, and all expenses for which invoices
     have been presented, on or before the Effective Date.

          (g) The General Administrative Agent shall have received from
     Holdings, for the account of each Lender, an amendment fee equal to such
     Lender's pro rata portion of $77,288.00.

     11. Representations and Warranties. After giving effect to the amendments
contained herein, on the Effective Date, Holdings and each of the Borrowers
hereby confirms, reaffirms and restates the representations and warranties set
forth in Section 8 of the Credit Agreement, except to the extent such
representations and warranties specifically relate to an earlier date, in which
case such representations and warranties shall be true and correct in all
material respects as of such earlier date; provided that each reference in such
Section 8 to "this Agreement" shall be deemed to be a reference both to this
Amendment and to the Credit Agreement as amended and modified by this Amendment.

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     12. Continuing Effect; No Other Amendments. Except as expressly amended
hereby, all of the terms and provisions of the Credit Agreement and the other
Loan Documents are and shall remain in full force and effect.

     13. No Default. No Default or Event of Default shall have occurred and be
continuing as of the Effective Date after giving effect to this Amendment.

     14. Counterparts. This Amendment may be executed in any number of
counterparts by the parties hereto, each of which shall be an original, and all
of which when taken together shall constitute one and the same instrument.
Delivery of an executed counterpart by facsimile transmission shall be effective
as delivery of a manually executed counterpart hereof.

     15. GOVERNING LAW. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.


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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered by their respective proper and duly authorized
officers as of the day and year first above written.


                             SMTC CORPORATION


                             By: /s/ Frank Burke
                                   ---------------
                                   Name:  Frank Burke
                                   Title:  Chief Financial Officer and Treasurer

                             HTM HOLDINGS, INC.


                             By: /s/ Frank Burke
                                 ---------------
                                   Name:  Frank Burke
                                   Title:  Authorized Signatory

                             SMTC MANUFACTURING CORPORATION OF CANADA


                             By: /s/ Frank Burke
                                 ---------------
                                   Name:  Frank Burke
                                   Title:    Authorized Signatory

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                             LEHMAN COMMERCIAL PAPER INC., as
                               General Administrative Agent

                             By: /s/ G. Andrew Keith
                                   -------------------
                                   Name:  G. Andrew Keith
                                   Title:    Authorized Signatory

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                           ACKNOWLEDGMENT AND CONSENT

     Each of the undersigned parties to the Amended and Restated Guarantee and
Collateral Agreement, dated as of July 27, 2000, as amended, supplemented or
otherwise modified from time to time, made by the undersigned in favor of Lehman
Commercial Paper Inc., as General Administrative Agent, for the benefit of the
Lenders, hereby (a) consents to the transactions contemplated by the Seventh
Amendment and Fourth Waiver to and under the Amended and Restated Credit and
Guarantee Agreement and (b) acknowledges and agrees that the guarantees and
grants of security interests contained in such Amended and Restated Guarantee
and Collateral Agreement and in the other Security Documents are, and shall
remain, in full force and effect after giving effect to the Seventh Amendment
and Fourth Waiver and all prior modifications to the Amended and Restated Credit
and Guarantee Agreement.

                                      SMTC MANUFACTURING CORPORATION OF
                                          CALIFORNIA
                                      SMTC MANUFACTURING CORPORATION OF
                                          COLORADO
                                      SMTC MANUFACTURING CORPORATION OF
                                          MASSACHUSETTS
                                      SMTC MANUFACTURING CORPORATION OF
                                          NORTH CAROLINA
                                      SMTC MANUFACTURING CORPORATION OF
                                          TEXAS
                                      SMTC MANUFACTURING CORPORATION OF
                                          WISCONSIN
                                      SMTC MEX HOLDINGS, INC.
                                      QUALTRON, INC.


                                      By: /s/ Frank Burke
                                         ----------------------------
                                         Name:  Frank Burke
                                         Title:   Authorized Signatory