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                                                                   Exhibit 10.5

                            ADVANCED POWER TECHNOLOGY

                    CHANGE TO EMPLOYMENT AGREEMENT AMENDMENT
                                  DATED 3/5/86



This change to the employment agreement amendment dated March 5, 1986
(attached), by and between Advanced Power Technology, Inc. ("Company") and John
Hess, VP Marketing and Discrete Product Operations ("Employee").

CHANGE:
FROM: Should the Agreement terminate upon the happenings of any of the events
defined in subparagraphs 2.1.a, 2.1.b, 2.1.c, 2.1.d, 2.1.f, the Company will pay
the Employee a severance pay equal to three months of salary upon termination,
in the event Employee would not have secured alternate employment. Should
Employee secure alternate employment earlier than three months after
termination, then the prorata temporaris portion of the severance pay paid to
the employee would become reimbursable to the Company.

TO: (f) Unilaterally by the Company without cause, in which event (Section 2.2
to the contrary notwithstanding) the Company will continue to pay Employee the
full amount due as salary for a period of thirty days following notice of
termination.

This change is made effective as of July 10, 2000.





                                       By:              /s/ John Hess
                                            ------------------------------------
                                            John Hess, VP Marketing & Discrete
                                            Product Operations

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                         ADVANCED POWER TECHNOLOGY, INC.

                              EMPLOYMENT AGREEMENT
                       (MANAGEMENT & TECHNICAL PERSONNEL)

         THIS EMPLOYMENT AGREEMENT is made and entered into this 6TH day of
November, 1985, by and between ADVANCED POWER TECHNOLOGY, INC., an Oregon
corporation ("Company") and John I. Hess, an individual ("Employee").

         WHEREAS, Company desires to employ Employee upon the terms and
conditions hereinafter set forth, and Employee desires to be so employed;

         NOW, THEREFORE, in consideration of the mutual promises contained
herein, Company and Employee agree as follows:

         1.       Employment

         Company hereby employs Employee as Vice-President of Operations of
Company with the powers and duties consistent with such position, and Employee
hereby accepts such employment, on the terms and conditions hereinafter set
forth. Employee, subject to the control of the Management of Company, agrees to
diligently utilize his or her best efforts to further the interests of the
Company and to discharge those responsibilities and duties required for the
planning, development, operation, promotion and advancement of the Company, and
such other duties as Company may require.

         2.       TERM AND TERMINATION

         2.1      This Agreement shall terminate upon the happening of any of
         the following events:

                  (a) By mutual agreement between Company and Employee;

                  (b) Unilaterally by Employee without cause;

                  (c) Upon the death of Employee;

                  (d) Upon the good faith determination of the Chief Executive
                  officer of Company that Employee has become so physically or
                  mentally disabled as to be incapable of satisfactorily
                  performing his or her duties hereunder for a period of ninety
                  (90) consecutive days, such determination

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                                                                              2

                  based upon a certificate as to such physical or mental
                  disability issued by a licensed physician and/or psychiatrist
                  (as the case may be) employed by Company; or

                  (e) For cause, that is to say only upon Employee's conviction
                  of a felony, commission of any material act of dishonesty
                  against Company, material breach of this Agreement by
                  Employee, or misconduct by Employee having a substantial
                  adverse effect on the business of Company.

                  (f) Without cause, in which event (Section 2.2 to the contrary
                  notwithstanding) Company will continue to pay Employee the
                  full amount due as salary for a period of thirty days
                  following notice of termination.

         2.2      In the event that this Agreement is terminated pursuant to
         Paragraph 2.1, neither Company nor Employee shall have any remaining
         duties or obligations hereunder, except that Company shall pay to
         Employee, or his or her representatives, such compensation as is due
         pursuant to Sub-Section 2.1(f) and Section 3. The provisions of
         Sections 4-9 shall survive termination.

         2.3      This Agreement shall not be terminated by any:

                  (a) Merger, whether Company is or is not the surviving
                  corporation; or

                  (b) Transfer of all or substantially all of the assets of
                  Company; or

                  (c) Voluntary or involuntary dissolution or liquidation of
                  Company; or

                  (d) Consolidation to which Company is a party.

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                                                                             3

                  In the event of any such merger, transfer of assets,
         dissolution, liquidation, or consolidation, the surviving corporation
         or transferee, as the case may be, shall be bound by and shall have the
         benefits of this Agreement, and Company shall take all action to ensure
         that such corporation or transferee is bound by the provisions of this
         Agreement.

         3.       COMPENSATION

         3.1      As the total consideration for the services which Employee
         agrees to render hereunder, Employee is entitled to the following:

                  (a) Beginning on October 22, 1985, an annual base salary of $
                  75,000 , subject to increase at the discretion of Company, in
                  accordance with the regular and ordinary payment practices of
                  Company. All payroll payments shall be subject to deduction of
                  payroll taxes and related deductions as required by law.

                  (b) Participation in all plans or programs sponsored by
                  Company for employees in general, including without limitation
                  participation in any group health plan, medical reimbursement
                  plan and life insurance plan, pension and profit sharing plan.

                  (c) Reimbursement of any and all reasonable and documented
                  expenses incurred by Employee from time to time in the
                  performance of his or her duties hereunder, including without
                  limitation entertainment expenses and air fare, taxi,
                  automobile, and other traveling expenses.

                  (d) after six (6) months of continuous employment, Employee
                  shall be eligible for five (5) working days of paid vacation;
                  after twelve (12) months of continuous employment, Employee
                  shall be eligible for ten (10) working days of paid vacation;
                  thereafter, Employee shall be eligible for ten (10) working
                  days of paid vacation upon the completion of each successive
                  twelve (12) month period of continuous employment . Paid
                  vacation is noncumulative and must be taken during the twelve
                  (12) months following accrual.

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                                                                             4


                  (e) Such other fringe benefits as Company, in its sole
                  discretion, may from time to time provide.

         3.2      Subject to the limitations contained in Paragraph 2.1, if
         Employee shall be absent on account of personal injuries or physical or
         mental illness, Employee shall continue to receive all payments
         provided in this Agreement; provided, however, that any such payments
         may, at the sole option of Company, be reduced by any amount that
         Employee receives for the period covered by such payments as disability
         compensation under insurance policies maintained by Company or under
         governmental programs.

         3.3      Company shall have the right to deduct from the compensation
         due to Employee hereunder any and all sums required for social security
         and withholding taxes and for any other federal, state, or local tax or
         charge which may be in effect or hereafter enacted or required as a
         charge on the compensation of Employee.

         3.4      Employee shall pay relocation expenses paid by Company if he
         or she voluntarily terminates employment within one year from date of
         employment.

         4.       NON-DISCLOSURE

                  Employee shall not disclose or use in any way, either during
his or her employment with Company or thereafter, except as required in the
course of his or her employment with Company, any confidential business or
technical information or trade secret acquired during his or her employment by
Company, whether or not conceived of, discovered, developed or prepared by
Employee, including without limitation any formulae, patterns, inventions,
procedures, processes, plans, devices, products, operations, techniques,
know-how, specifications, data, compilations of information, customer lists,
records, financing or production methods, costs, employees, and information
concerning specific customer requirements, preferences, practices and methods of
doing business, all of which are exclusive and valuable property of Company.

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                                                                             5

         5.       ASSIGNMENT OF PROPRIETARY INTERESTS

                  Employee hereby assigns and transfers to Company his or her
entire right, title and interest in and to any and all inventions, improvements,
processes, sketches, methods of production, designs, discoveries, ideas (whether
or not shown or described in writing) or services (collectively, "inventions"),
whether or not patentable, which are made, conceived or first reduced to
practice by Employee with Company's equipment, supplies, facilities, or trade
secrets and on Company's time, or which relates to the business of Company or
Company's actual or anticipated research or business development or which
results frorn any work performed by the Employee for Company. Employee agrees
that Company shall have the right to keep such inventions as trade secrets. To
permit Company to claim rights to which it may be entitled, the Employee agrees
to promptly disclose to Company in confidence all inventions which the Employee
makes, conceives or first reduces to practice during the course of his or her
employment or within one year after termination thereof if such inventions
relate to a product, process or service upon which Employee worked during the
period of his or her employment by Company, and all patent or copyright
applications filed by the Employee within a year after termination of this
Agreement. Both during and after the period of employment with Company, Employee
shall further assist Company in obtaining patents or copyrights on all
inventions deemed patentable or copyrightable by Company in the United States
and in all foreign countries, and shall execute all documents and do all things
necessary to obtain letters patent and/or copyrights, to vest Company with full
and extensive title thereto, and to protect Company's rights against
infringement by others. Employee further agrees that any patent application
filed within a year after termination of his or her employment on an invention
for which the Employee was partially or totally responsible shall be presumed to
relate to an invention made during the term of the Employee's employment unless
the Employee can provide evidence to the contrary.

         6.       TANGIBLE ITEMS AS PROPERTY OF COMPANY

                  Excluding any personal property owned by Employee prior to the
date hereof, all files, records, documents, drawings, plans, specifications,
manuals, books, forms, receipts, notes, reports, memoranda, studies, data,

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                                                                             6


calculations, recordings, catalogues, compilations of information,
correspondence and all copies, abstracts and summaries of the foregoing,
instruments, tools and equipment and all other physical items related to the
business of Company, other than a merely personal item of a general professional
nature, whether of a public nature or not, and whether prepared by Employee or
not, are and shall remain the exclusive property of Company and shall not be
removed from the premises of Company under any circumstances whatsoever without
the prior written consent of Company, and the same shall be promptly returned to
Company by Employee on the expiration or termination of his or her employment
with Company or at any time prior thereto upon the request of Company.

         7.       SOLICITATION OF CUSTOMERS AND EMPLOYEES

                  Both during and within one year after the period of
employment, Employee shall not in any way attempt to interfere with the business
of Company and, shall not call on, solicit, interfere with or attempt to entice
away, either directly or indirectly, any employee or customer of Company with
whom he or she became acquainted during his or her employment with Company,
either for his or her own benefit or purposes or for the benefit or purposes of
any other person, partnership, corporation, firm, association or other business
organization, entity or enterprise.

         8.       INJUNCTIVE RELIEF

                  Employee hereby acknowledges and agrees that it would be
difficult to fully compensate Company for damages resulting from the breach or
threatened breach of Sections 4, 5, 6, 7 or 8 of this Agreement and,
accordingly, that Company shall be entitled to temporary and injunctive relief,
including temporary restraining orders, preliminary injunctions and permanent
injunctions, to enforce such Sections without the necessity of proving actual
damages therewith. This provision with respect to injunctive relief shall not,
however, diminish Company's right to claim and recover damages.


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                                                                             7


         9.       INDEMNIFICATION

                  Company shall, to the maximum extent permitted by law,
indemnify and hold Employee harmless against expenses, including reasonable
attorney's fees, judgments, fines, settlements, and other amounts actually and
reasonably incurred in connection with any proceeding arising by reason of
Employee's employment with Company if Employee, in incurring the above expenses,
acted in good faith and in a manner Employee believed to be in the best
interests of Company, and, in the case of a criminal proceeding, had no
reasonable cause to believe Employee's conduct was unlawful.

         10.      COPIES OF AGREEMENT

                  Employee authorizes Company to send a copy of this Agreement
to any and all future employers which he or she may have, and to any and all
persons, firms, and corporations, with whom he or she may become affiliated in a
business or commercial enterprise, and to inform any and all such employers,
persons, firms or corporations that Company intends to exercise its legal rights
should Employee breach the terms of this Agreement or should another party
induce a breach of Employee's part.

         11.      SEVERABLE PROVISIONS

                  The provisions of this Agreement are severable and if any one
or more provisions may be determined to be illegal or otherwise unenforceable,
in whole or in part, the remaining provisions, and any partially unenforceable
provisions to the extent enforceable, shall nevertheless be binding and
enforceable.

         12.      BINDING AGREEMENT

                  This Agreement shall inure to the benefit of and shall be
binding upon Company, its successors and assigns.

         13.      CAPTIONS

                  The Section captions are inserted only as a matter of
convenience and reference and in no way define, limit or describe the scope of
this Agreement or the intent of any provisions hereof.

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         14.      ENTIRE AGREEMENT

                  This Agreement contains the entire agreement of the parties
relating to the subject matter hereof, and the parties hereto have made no
agreements, representations or warranties relating to the subject matter of this
Agreement that are not set forth herein. No modification of this Agreement shall
be valid unless made in writing and signed by the parties hereto.

         15.      GOVERNING LAW

                  This Agreement shall be governed and construed in accordance
with the laws of the State of Oregon.

         16.      NOTICES

                  Any notice or demand required or permitted to be given
hereunder shall be in writing and shall be deemed effective upon the personal
delivery thereof or, if mailed, forty-eight hours after having been deposited in
the United States mails, postage prepaid, and addressed to the party to whom it
is directed at the address set forth below:

                  If to Company:

                  ADVANCED POWER TECHNOLOGY, INC.
                  405 SW Columbia Street
                  Bend, Oregon  97702

                  With a copy to:

                  Thomas J. Poletti, Esq.
                  Freshmen, Marantz, Orlanski, Comsky & Deutsch
                  9100 Wilshire Blvd., Ste. 8-E
                  Beverly Hills, CA  90212

                  If to EMPLOYEE:

                  John I. Hess
                  60246 Woodside Road
                  Bend, Oregon  97702

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                                                                             9


Either party may change the address to which such notices are to be addressed by
giving the other party notice in the manner herein set forth.

                  IN WITNESS WHEREOF, the parties have executed this Agreement
on the day and year first written above.

                                  ADVANCED POWER TECHNOLOGY, INC. an Oregon
                                  corporation ("Company")


                               -------------------------------------------------
                               RU   /s/ Patrick Sireta     11.6.85
                                 -------------------------

                               Patrick Sireta
                               President and Chief Executive Officer




                                      /s/ John I. Hess          11/6/85
                               -------------------------------------------------
                               John I. Hess

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                            ADVANCED POWER TECHNOLOGY

                        AMENDMENT TO EMPLOYMENT AGREEMENT

This amendment to the employment agreement signed on November 6, 1985, is made
and entered into this 5th day of March 1986, by and between Advanced Power
Technology, Inc. an Oregon Corporation ("Company") and John Hess an individual
("Employee").

Whereas, Employee is an employee of Company upon the terms and conditions
defined in Employment Agreement signed on November 6, 1985.

Now, therefore, in consideration of the mutual promises contained herein,
Company and Employee agree as follows:

Should the Agreement terminate upon the happening of any of the events defined
in subparagraphs 2.1.a, 2.1.b, 2.1.c, 2.1.d, 2.1.f, the Company will pay
Employee a severance pay equal to three months of salary upon termination, in
the event Employee would not have secured alternate employment. Should Employee
secure alternate employment earlier than three months after termination, then
the prorata temporaris portion of the severance pay payed to the Employee would
become reimbursable to the Company.

This amendment is made effective as of March 5, 1986 and for a period of 12
months.

In witness whereof, the parties have executed this Amendment on the day and year
first written above.

                                     ADVANCED POWER TECHNOLOGY, INC.
                                     an Oregon Corporation "Company":


                                     By:       /s/ Patrick Sireta
                                        ----------------------------------------
                                           Patrick Sireta
                                           President & Chief Executive Officer


                                     Employee

                                      /s/ John Hess                    3/5/86
                                     -------------------------------------------
                                          John Hess