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                                                                   EXHIBIT 10.86

Mr. Philip Frey, Jr.
Chairman
Microsemi Corporation
2830 S. Fairview Street
Santa Ana, California 92704

Dear Phil:

        Re: Transition and Consulting Agreement

The purpose of this letter is to confirm a formal arrangement between Microsemi
Corporation (MSC) and your transition from your role as Chairman, Chief
Executive Officer and President of MSC to your continuing role as the Chairman
of the Board of Directors (BOD) and new role as a Consultant to MSC.

Also this letter restates, amends and supersedes the version of this letter as
previously signed on, before or about December 18, 2000.

As discussed with the BOD you will retire December 18, 2000, but continue to
support MSC in a consulting role.  The following items outline the specific
terms and conditions that are applicable regarding this transition and your
services as a consultant to MSC.

1.  The consulting period shall be from December 18, 2000, and shall continue
    until, December 17, 2001.

2.  In your consulting role, you shall provide consulting services as specified
    in writing by the BOD, or its designee. These assignments may cover a
    variety of projects, but will focus primarily on strategic planning,
    business acquisitions, disposition of certain assets and interface with key
    military and aerospace accounts. As a consultant, you are an independent
    contractor, responsible for the means and manner of your performance of
    these consulting services.

3.  MSC agrees to pay you the sum of Twenty Five Thousand Dollars ($ 25,000) per
    month during the consulting period under this agreement.

4.  At the date you retire you will receive pay out of all accrued vacation
    (1,574 hours) and Three Hundred and Ten Thousand Eight Hundred and Eighteen
    Dollars ($310,818) as payment of your Executive Performance Bonus for your
    fiscal year 2000 performance.

5.  Based on your December 18, 2000 retirement date, you will receive the
    initial payment of benefits from the Microsemi Corporation Supplemental
    Executive Retirement Plan of One Hundred Sixteen Thousand Five Hundred and
    Fifty Six Dollars and ninety-six Cents ($116,556.96) on February 1, 2001.

6.  MSC will provide you medical, dental and life insurance coverage during the
    consulting period of this Agreement through the company's benefits plan. You
    will not be eligible to participate in other benefit, bonus or compensations
    plans except as provided by your role on the Board of Directors and by your
    participation in the Microsemi Corporation Supplemental Executive Retirement
    Plan.
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7.  As part of the medical benefits commitment made by the BOD, the company will
    provide you a Medicare Supplemental Insurance policy effective January 1,
    2002. This is a lifetime benefit in recognition of your long service and
    significant contributions as Chairman, President and CEO.

8.  As part of this Agreement Microsemi Corporation agrees to pay the $34,000
    premium for your existing life insurance policy for a period of twelve
    months starting with the date of your retirement.

9.  It is understood you will be taking some personal time during this
    transition and may not be available for consulting assignments during the
    last two weeks of December and possibly some time in January.

10. All of the stock options granted to you through December 2000 will continue
    to vest until their expiration as provided in your stock option agreements,
    and to the extent that each such option agreement is vested or hereafter
    vests, it shall remain exercisable for a period ending on the earlier to
    occur of (a) the first anniversary of your death or (b) the latest
    expiration date specified in the option agreement (generally five years from
    the date of grant).

11. The Board of Directors will approve a resolution awarding you options for
    Ten Thousand (10,000) shares of MSC stock upon your retirement. The Board
    will also award you options for Five Thousand (5,000) shares of Microsemi
    Corporation stock annually, starting in 2002 as part of the recognition for
    your service and as long as you continue to serve as Chairman. Your service
    as Chairman will also include a Fifteen Thousand-Dollar ($15,000) quarterly
    retainer.

12. MSC shall pay you a $1,000 per month car allowance during the consulting
    period and reimburse you for reasonable expenses that are incurred as a
    result of the work performed by you outside of the Santa Ana, California
    area.

13. Payments made under this Agreement shall be at a rate commensurate with the
    value of the services or expenses described herein. These payments shall not
    include any amount, which will be used improperly by you to influence the
    actions of another person on MSC's behalf.

14. To the extent required by law, you shall have the rights under the
    Consolidated Omnibus Budget Reconciliation Act ("COBRA"), or any successor
    statute.

15. Excise Taxes. You will be financially responsible for any taxes imposed on
    you on account of payments by MSC to you; provided, however, that if all or
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    any portion of the amounts payable to you or on your behalf under this
    letter agreement or otherwise are subject to the excise tax imposed by
    Section 4999 of the Internal Revenue Code of 1986, as amended (or similar
    state tax and/or assessment), the Company shall pay you an amount necessary
    to place you in the same after-tax position as you would have been had no
    such excise tax been imposed. The amount payable pursuant to the preceding
    sentence shall be grossed-up to the extent necessary to pay income and
    excise taxes due on such amount. The determination of the amount of any such
    tax indemnity shall initially be made by the independent accounting firm
    then employed by the Company. If at a later date it is determined (pursuant
    to final regulations or published rulings of the IRS, final judgment of a
    court of competent jurisdiction or otherwise) that the amount of excise
    taxes payable by you is greater than the amount initially so determined,
    then the Company (or its successor) shall pay you an amount equal to the sum
    of (1) such additional excise taxes, (2) any interest, fines and penalties
    resulting from such underpayment, plus (3) a gross-up amount necessary to
    reimburse you for any income, excise or other taxes payable by you with
    respect to the amounts specified in (1) and (2) above, and the reimbursement
    provided by this clause (3).

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16. Indemnification. For at least ten (10) years following the date of your
    retirement, you shall continue to be indemnified under the Company's
    Certificate of Incorporation and Bylaws at least to the same extent
    indemnification was available prior to the date of retirement and permitted
    by law, and you shall be insured under the directors' and officers'
    liability insurance, the fiduciary liability insurance and the professional
    liability insurance policies that are the same as, or provide coverage at
    least equivalent to, those applicable or made available by the Company to
    the then members of senior management of the Company. Independent of such
    provision, if at any time you are made, or threatened to be made, a party to
    any legal action or proceeding, whether civil or criminal, by reason of the
    fact that you are or were a director or officer of the Company or serves or
    served any other corporation or entity fifty percent (50%) or more owned or
    controlled by the Company in any capacity at the Company's request, you
    shall be indemnified by the Company, and the Company shall pay your related
    expenses when and as incurred, all to the full extent permitted by law.

17. You shall deliver to MSC detailed reports and documentation if requested by
    the BOD or its designee. Your reports to MSC should disclose all work or
    services completed to date during the course of your assigned projects and
    shall be supported by appropriate documentation, such as graphs, computer
    programs, formulae, sketches, drawings, summaries and the like.

18. The liaison and general administration of this Agreement shall be through
    the BOD or its designee.

19. You shall maintain confidential and secret all MSC information which has
    been or may be disclosed to you as being confidential or secret in
    character, and you shall not disclose this information to any other person,
    firm or corporation. You shall also maintain as confidential MSC's "know-
    how" and future plans relating to the fields of endeavor in which you
    perform your services as part of this Agreement. The terms of this section
    shall survive indefinitely after any termination of the consulting period.

20. You represent and warrant that no part of the payment of any sums due and
    payable under this Agreement will in any way be paid or distributed to MSC
    or its subsidiaries and affiliates, or any of the directors, officers,
    employees or agents thereof.

21. The consulting period shall continue and is irrevocable during the initial
    term specified above. However, if the consulting period is extended, MSC may
    terminate this Agreement for its convenience upon ninety days (90) prior
    written notice. In such event, MSC's sole obligation shall be to pay you for
    any authorized work performed prior to the end of such notice period in the
    amounts as set forth in paragraphs 3, 6 and 12 above.

22. We agree to attempt to settle any dispute arising out of this Agreement, the
    execution thereof, or in connection therewith, through friendly consultation
    and negotiation in the spirit of mutual cooperation. However, if settlement
    cannot be reached within a reasonable time, then the dispute shall first be
    submitted to a mutually acceptable neutral advisor for Non-Binding
    Mediation. Neither of us shall unreasonably withhold acceptance of such
    advisor, and the party requesting such Mediation shall make the selection
    within thirty (30) days after written notice. Any disputes arising from this
    Agreement, which we cannot resolve in good faith within three (3) months of
    the date of the written request for Mediation, shall be submitted to an
    Arbitration Association consisting of retired judges for arbitration in
    accordance with its rules of procedure. The party seeking ADR as provided by
    this Agreement, agrees that the other party shall select the venue for such
    mediations and arbitration. We agree that the Arbitrator's award shall be
    final and binding upon us. During Arbitration, the terms and conditions of
    this Agreement shall be executed continuously by us except for matters in
    dispute. Each party shall be responsible for all costs associated with the
    preparation and representation by attorneys, or any other persons retained
    thereby, to assist in connection with

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    any such Alternative Dispute Resolution. However, all costs charged by the
    mutually agreed upon Alternative Dispute Resolution Entity, shall be equally
    shared by us.

23. This Agreement shall be binding upon and inure to the benefit of MSC's
    successors and assigns, and shall be binding upon and inure to the benefit
    of your heirs, legal representatives, successors and assigns.

24. The validity, construction and performance of this Agreement, and the legal
    relations between the parties shall be governed by and construed in
    accordance with the laws of the State of California.

25. This Agreement shall not be assignable by you without MSC's prior written
    consent, and any purported assignment not permitted hereunder including full
    or partial assignment or delegation to any agent or subcontractor, shall be
    deemed void. This Agreement may be modified only by an instrument in writing
    and signed by you and duly authorized representatives of MSC Board of
    Directors. This document constitutes the entire Agreement between us with
    respect to the subject matter hereof, and supersedes all previous
    communications, representations, understanding and agreements either oral or
    written, between the parties or any official or representative thereof. The
    Agreement dated November 17, 1997 between the Company and you concerning
    generally a termination of your employment and change in control is hereby
    specifically terminated by written agreement effective as of the date of
    your retirement, and thereafter the Agreement dated November 17, 1997 shall
    be of no force or effect whatsoever.

26. In the event any court of competent jurisdiction determines that a
    particular provision of this Agreement is unenforceable and/or contrary to
    law, this will not affect the validity and enforceability of the other
    provisions of this Agreement in such jurisdiction, or the validity and
    enforceability of this Agreement as a whole in any other jurisdiction.

27. MSC's obligations under this Agreement shall not constitute the personal
    obligations of its shareholders, or of it's directors, officers, employees,
    consultants, agents or invitees, and you shall look only to the assets of
    MSC for the satisfaction of any liability with respect to this Agreement,
    and shall not seek recourse against its shareholders, or against its
    directors, officers, employees, consultants, agents, or invitees, or against
    their personal assets for such satisfaction.

28. Separate Counsel. You have been invited and given opportunity to engage
    separate and independent counsel to review or negotiate this Agreement, and
    you have either done so or chosen not to engage counsel.

Phil, we would like to personally thank you for your support and your many years
of service to Microsemi Corporation, its customers, employees and shareholders.
The corporation's success in large measure is a function of your many years of
dedication, contribution and sacrifice.  Much of what Microsemi has accomplished
is a direct result of your efforts.  You move into your new roles with the very
best wishes from your colleagues, co-workers and the Board of Directors.

If you agree with the foregoing terms and conditions please so indicate by
signing and dating one copy hereof at the place provided and return to us for
our records.

Respectfully,

/S/  JAMES J. PETERSON                  /S/  JOSEPH M. SCHEER
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James J. Peterson                       Joseph M. Scheer
CEO and President                       Chairman, Compensation Committee

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CC:  John Holtrust, Corporate VP, Human Resources

                              AGREED AND ACCEPTED
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            By:   /S/  PHILIP FREY, JR.
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                  Philip Frey, Jr.


Date:   January 24, 2001

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