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                                                                    Exhibit 10.5

                            ASSIGNMENT AND ACCEPTANCE
                            -------------------------

                           Dated as of October 1, 1999

     Reference is made to the Amended and Restated Multicurrency Revolving
Credit and Term Loan Agreement, dated as of January 31, 1996 (as from time to
time amended and in effect, the "Credit Agreement"), by and among TERADYNE INC.
(the "Borrower"), the banking institutions referred to therein as Banks
(collectively, the "Banks"), and BANKBOSTON, N.A., a national banking
association, as agent (in such capacity, the "Agent") for the Banks. Capitalized
terms used herein and not otherwise defined shall have the meanings assigned to
such terms in the Credit Agreement.

     State Street Bank and Trust Company, N.A. (the "Assignor") and Citizens
Bank of Massachusetts (the "Assignee") hereby agree as follows:

     1. ASSIGNMENT. Subject to the terms and conditions of this Assignment and
Acceptance, the Assignor hereby sells and assigns to the Assignee, and the
Assignee hereby purchases and assumes without recourse to the Assignor, a 100%
interest in and to the rights, benefits, indemnities and obligations of the
Assignor under the Credit Agreement.

     2. ASSIGNOR'S REPRESENTATIONS. The Assignor (i) represents and warrants
that (A) it is legally authorized to enter into this Assignment and Acceptance,
and (B) immediately after giving effect to all assignments which have not yet
become effective, the Assignor's Commitment Percentage will be sufficient to
give effect to this Assignment and Acceptance, (ii) makes no representation or
warranty, express or implied, and assumes no responsibility with respect to any
statements, warranties or representations made in or in connection with the
Credit Agreement or any of the other Loan Documents or the execution, legality,
validity, enforceability, genuineness, sufficiency or value of the Credit
Agreement, any of the other Loan Documents or any other instrument or document
furnished pursuant thereto or the attachment, perfection or priority of any
security interest or mortgage, other than that it is the legal and beneficial
owner of the interest being assigned by it hereunder free and clear of any claim
or encumbrance; and (iii) makes no representation or warranty and assumes no
responsibility with respect to the financial condition of the Borrower or any of
its Subsidiaries or any other Person primarily or secondarily liable in respect
of any of the Obligations, or the performance or observance by the Borrower or
any of its Subsidiaries or any other Person primarily or secondarily liable in
respect of any of the Obligations of any of its obligations under the Credit
Agreement or any of the other Loan Documents or any other instrument or document
delivered or executed pursuant thereto.


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     3. ASSIGNEE'S REPRESENTATIONS. The Assignee (i) represents and warrants
that (A) it is duly and legally authorized to enter into this Assignment and
Acceptance, (B) the execution, delivery and performance of this Assignment and
Acceptance do not conflict with any provision of law or of the charter or
by-laws of the Assignee, or of any agreement binding on the Assignee, (C) all
acts, conditions and things required to be done and performed and to have
occurred prior to the execution, delivery and performance of this Assignment and
Acceptance, and to render the same the legal, valid and binding obligation of
the Assignee, enforceable against it in accordance with its terms, have been
done and performed and have occurred in due and strict compliance with all
applicable laws; (ii) confirms that it has received a copy of the Credit
Agreement, together with copies of the most recent financial statements
delivered pursuant thereto and such other documents and information as it has
deemed appropriate to make its own credit analysis and decision to enter into
this Assignment and Acceptance; (iii) agrees that it will, independently and
without reliance upon the Assignor, the Agent or any other Bank and based on
such documents and information as it shall deem appropriate at the time,
continue to make its own credit decisions in taking or not taking action under
the Credit Agreement; (iv) represents and warrants that it is an Eligible
Assignee; (v) appoints and authorizes the Agent to take such action as agent on
its behalf and to exercise such powers under the Credit Agreement and the other
Loan Documents as are delegated to the Agent by the terms thereof, together with
such powers as are reasonably incidental thereto; and (vi) agrees that it will
perform in accordance with their terms all the obligations which by the terms of
the Credit Agreement are required to be performed by it as a Bank.

     4. EFFECTIVE DATE. The effective date for this Assignment and Acceptance
shall be the date first set forth above (the "Effective Date"). Following the
execution of this Assignment and Acceptance and the consent of the Borrower
hereto having been obtained, each party hereto shall deliver its duly executed
counterpart hereof to the Agent for consent by the Agent and recording in the
Register by the Agent. Schedule 1 to the Credit Agreement shall thereupon be
replaced as of the Effective Date by the Schedule 1 annexed hereto.

     5. RIGHTS UNDER CREDIT AGREEMENT. Upon such acceptance and recording, from
and after the Effective Date, (i) the Assignee shall be a party to the Credit
Agreement and, to the extent provided in this Assignment and Acceptance, have
the rights and obligations of a Bank thereunder, and (ii) the Assignor shall,
with respect to that portion of its interest under the Credit Agreement assigned
hereunder, relinquish its rights and be released from its obligations under the
Credit Agreement; provided, however, that the Assignor shall retain its rights
to be indemnified pursuant to the Credit Agreement with respect to any claims or
actions arising prior to the Effective Date.

     6. PAYMENTS. Upon such acceptance of this Assignment and Acceptance by the
Agent and such recording, from and after the Effective Date, the Agent shall

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make all payments in respect of the rights and interests assigned hereby
(including payments of principal, interest, fees and other amounts) to the
Assignee. The Assignor and the Assignee shall make any appropriate adjustments
in payments for periods prior to the Effective Date by the Agent or with respect
to the making of this assignment directly between themselves. In addition, the
Agent hereby agrees to waive the recordation fee of $3,000 required by ss.12.3
of the Credit Agreement.

     7. GOVERNING LAW. THIS ASSIGNMENT AND ACCEPTANCE IS INTENDED TO TAKE EFFECT
AS A SEALED INSTRUMENT TO BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE
LAWS OF THE COMMONWEALTH OF MASSACHUSETTS (WITHOUT REFERENCE TO CONFLICT OF
LAWS).

     8. COUNTERPARTS. This Assignment and Acceptance may be executed in any
number of counterparts which shall together constitute but one and the same
agreement.

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     IN WITNESS WHEREOF, intending to be legally bound, each of the undersigned
has caused this Assignment and Acceptance to be executed on its behalf by its
officer thereunto duly authorized, as of the date first above written.

                                       STATE STREET BANK AND TRUST
                                       COMPANY, Assignor

                                       By:_____________________________________
                                               Name:
                                               Title:

                                       CITIZENS BANK OF
                                       MASSACHUSETTS, Assignee

                                       By:_____________________________________
                                               Name:
                                               Title:

CONSENTED TO:

TERADYNE INC.

By:_____________________________________
       Name:
       Title:

BANKBOSTON, as Agent

By:_____________________________________
       Name:
       Title:

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                                   SCHEDULE 1
                                   ----------

          Immediately following the Effective Date:

<TABLE>
<S>                                                                <C>
          Commitment of State Street Bank and Trust Company        $0
          Commitment of Citizens Bank of Massachusetts             $10,500,000
</TABLE>

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