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                                                                    Exhibit 10.L


[ALPHA INDUSTRIES, INC. LETTERHEAD]


May 30, 2000


Jean Pierre Gillard
Alpha Industries, Inc.
20 Sylvan Road
Woburn, MA  01801


Re:  Separation Arrangement

Dear J.P.:

This letter is to confirm the separation arrangements that we have agreed on.
This letter implements the Severance Agreement between you and Alpha dated
December 11, 1998 (the "Agreement"), with certain changes noted below.

In consideration of your willingness to continue providing consulting services
after your separation and to be subject to a longer noncompetition period, Alpha
is willing to provide you with certain benefits provided for in the Agreement.
The full statement of this arrangement is set out below.

1.   Effective on May 31, 2000, you will move to part-time employee status and
     will cease to be an officer of the corporation. Your responsibilities will
     be as mutually agreed to between you and Alpha's Chief Executive Officer.

2.   You will continue to receive your full base salary, as currently set, paid
     weekly, subject to normal withholding. You will be eligible for medical and
     dental insurance coverage and for the deferred compensation plan, subject
     to the same terms, conditions and payments as active employees of Alpha,
     but you will not be eligible for any other employee benefits. You will
     continue to be eligible to receive stock options or other incentive
     compensation so long as you are an employee, but the decision to grant such
     options or compensation will be in the sole discretion of Alpha's CEO.

3.   Effective on May 31, 2000, all of your then outstanding Alpha stock
     options, whether or not by their terms then exercisable, will, subject to
     their other terms and conditions, become immediately exercisable and remain
     exercisable until May 30, 2001.

4.   You may elect to retire at any time after May 31, 2000, in which case you
     will become an independent consultant to Alpha, advising the company on
     business


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Jean Pierre Gillard
May 30, 2000
Page 2


     development, mergers and acquisitions, wireless markets and other areas
     within your expertise. Your activities and schedule will be as mutually
     agreed to between you and Alpha's Chief Executive Officer. This consulting
     arrangement will continue until May 30, 2002, unless otherwise mutually
     agreed to by you and Alpha's CEO. As a consultant, you will receive
     consulting fees for your availability and services equal to your current
     base salary, paid weekly. You will be reimbursed for your reasonable
     out-of-pocket expenses incurred in the performance of your consulting
     duties. You will be eligible for medical and dental insurance coverage and
     for the deferred compensation plan, subject to the same terms, conditions
     and payments as active employees of Alpha, but you will not be eligible for
     any other employee benefits.

5.   From the date of this letter until May 30, 2002 (the "Noncompete Period"),
     you will not, directly or indirectly, whether as owner, partner,
     shareholder, director, consultant, agent, employee, or otherwise, or
     through any person, engage in any employment, consulting or other activity
     which competes with the business of Alpha or any subsidiary or affiliate of
     Alpha (collectively, the "Company"). You acknowledge and agree that your
     direct or indirect participation in the conduct of such competing business
     alone or with any person will materially impair the business and prospects
     of Alpha. During the Noncompete Period, you will not (i) attempt to hire
     any director, officer, employee or agent of the Company, (ii) assist in
     such hiring by any other person, (iii) encourage any person to terminate
     his or her employment or business relationship with the Company, (iv)
     encourage any customer or supplier of the Company to terminate its
     relationship with the Company, or (v) obtain, or assist in obtaining, for
     your own benefit (other than indirectly as an employee of the Company) any
     customer of the Company. If any of the restrictions provided for in this
     Section 6 are adjudicated to be excessively broad as to scope, geographic
     area, time or otherwise, said restriction shall be reduced to the extent
     necessary to make the restriction reasonable and shall be binding on you as
     so reduced. Any provisions of this Section 6 not so reduced shall remain in
     full force and effect. You understand and acknowledge that the Company's
     remedies at law for breach of any of the restrictions in this Section are
     inadequate and that any such breach will cause irreparable harm to the
     Company. You therefore agree that in addition and as a supplement to such
     other rights and remedies as may exist in the Company's favor, the Company
     may apply to any court having jurisdiction to enforce the specific
     performance of the restrictions in this Section, and may apply for
     injunctive relief against any act which would violate those restrictions.

6.   Alpha agrees that you may provide consulting services to other companies,
     but only subject to your noncompetition obligations under section 5.


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Jean Pierre Gillard
May 30, 2000
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7.   This agreement contains the entire understanding of the parties concerning
     its subject matter. This agreement may be modified only by a written
     instrument executed by both parties. This agreement supersedes all prior
     agreements relating to your employment or severance, including without
     limitation the Severance Agreement dated December 11, 1998. This agreement
     will be governed by and construed in accordance with the laws of the
     Commonwealth of Massachusetts.

Please sign both copies of this letter and return one to me. If you have any
questions, please feel free to call me or Jim Nemiah.

Sincerely,


/s/ David J. Aldrich
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David J. Aldrich
President and CEO



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                                    AGREED TO:


                                    /s/ J. P. Gillard
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                                    Date:  5/30/00
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