AMENDMENT AND WAIVER TO COMMERCIAL LOAN AGREEMENT AND LOAN DOCUMENTS

Exhibit 10.8

AMENDMENT AND WAIVER

TO

COMMERCIAL LOAN AGREEMENT AND LOAN DOCUMENTS

THIS AMENDMENT AND WAIVER TO COMMERCIAL LOAN AGREEMENT AND LOAN DOCUMENTS (this “Amendment”), made effective as of June 26, 2009 (the “Effective Date”), is by and among RBS CITIZENS NATIONAL ASSOCIATION, a national banking association and successor by merger to Citizens Bank New Hampshire with a place of business at 875 Elm Street, Manchester, New Hampshire 03101 (the “Bank”); MICRONETICS, INC., a Delaware corporation with an executive office at 26 Hampshire Drive, Hudson, New Hampshire 03051 (the “Borrower”); MICROWAVE & VIDEO SYSTEMS, INC., a Connecticut corporation with an executive office at 160B Shelton Road, Monroe, Connecticut 06468, MICROWAVE CONCEPTS, INC., and STEALTH MICROWAVE, INC., each a Delaware corporation, and all with an executive office at 26 Hampshire Drive, Hudson, New Hampshire 03051; and MICA MICROWAVE CORPORATION, a Delaware corporation with an executive office at 1096 Mellon Avenue, Manteca, California 95337 and formerly known as “Del Merger Subsidiary, Inc.” (individually, a “Guarantor”, and collectively, the “Guarantors”).

R E C I T A L S :

WHEREAS, the Bank has extended to the Borrower certain credit facilities consisting of a revolving line of credit loan in the principal amount of up to Five Million Dollars ($5,000,000.00) (the “Revolving Line of Credit Loan”), and a term loan in the original principal amount of Six Million Five Hundred Thousand Dollars ($6,500,000.00) (the “Term Loan”), all pursuant to a certain Commercial Loan Agreement dated March 30, 2007 by and among the Bank, the Borrower and the Guarantors, as amended to date (the “Loan Agreement”) and the Loan Documents as defined therein;

WHEREAS, the Borrower would be in default in the performance of certain of its obligations under the Loan Agreement in that it has violated its financial covenants under Sections III. A. (i.e., Debt Service Coverage) and B. (i.e., ratio of Total Funded Debt to EBITDA) of Schedule B of the Loan Agreement for the fiscal quarter ending March 31, 2009 (collectively, the “Covenant Defaults”); and

WHEREAS, the Bank, at the request of the Borrower and the Guarantors, has agreed to (i) waive the Covenant Defaults, (ii) suspend the testing of the financial covenants under Sections III. A. and B. of Schedule B of the Loan Agreement until the fiscal quarter ending March 31, 2010, and (iii) amend said financial covenants in certain respects, all upon and subject to the terms and conditions of this Amendment. Capitalized terms not otherwise defined herein shall have the meanings ascribed to them in the Loan Agreement.

NOW, THEREFORE, in consideration of the foregoing premises and the mutual covenants, agreements and promises contained herein, and other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the parties agree as follows:

1. Waiver of Covenant Defaults . The Bank hereby acknowledges the Borrower’s Covenant Defaults under the Loan Agreement as of the fiscal quarter ending March 31, 2009. The Bank hereby waives the Covenant Defaults by the Borrower solely as of the fiscal quarter ending March 31, 2009 (the “Waiver”). The Waiver applies only to Borrower’s compliance with the financial covenants under Sections III. A. and B. of Schedule B of the Loan Agreement as of the Fiscal Quarter ending March 31, 2009. The Bank does not waive compliance by the Borrower with any of its other covenants under the Loan Agreement or Loan Documents or for any other dates or for any other periods.

2. Amendments to Loan Agreement .

(a) Section III.A.2 of the Loan Agreement shall be, and hereby is, deleted in its entirety and replaced with the following new Section II.A.2:

“2. Applicable Margin . The term “Applicable Margin” means the annual percentage rate to be added to the Bank’s prime rate to determine the Prime Rate under this Agreement and LIBOR to determine the LIBOR Rate under this Agreement. The Applicable Margin shall be 4.25% per annum with respect to the Revolving Line of Credit Loan, and 3.75% with respect to the Term Loan, until a determination is made otherwise in accordance with this Agreement based upon the ratio of Total Funded Debt to EBITDA as of the Fiscal Quarter ending March 31, 2010. The Applicable Margin for both the Revolving Line of Credit Loan and the Term Loan will be adjusted (up or down) on a quarterly basis as determined by Borrower’s Total Funded Debt to EBITDA ratio beginning with the Fiscal Quarter ending March 31, 2010. Adjustments in the Applicable Margin will be determined by reference to the following grid:

Within forty-five (45) days of the end of each Fiscal Quarter, beginning with the Fiscal Quarter ending March 31, 2010, of Borrower (provided that Borrower shall have ninety (90) days after the end of each Fiscal Year thereafter), Borrower shall (a) deliver to the Bank its Financial Statements covering such Fiscal Quarter (which shall be management prepared financial statements for purposes hereof), (b) deliver to the Bank the quarterly financial covenant compliance certificate of Borrower, and (c) certify to Bank the then Total Funded Debt to EBITDA ratio of Borrower and Borrower’s determination of Applicable Margin therefrom on such

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form as the Bank may from time to time specify. Borrower shall also provide to the Bank such other reasonable information as the Bank may request of Borrower to verify its determination of the Applicable Margin. As of the tenth (10th) Business Day after the Borrower’s delivery of all of the above-referenced items to the Bank, the Bank shall notify Borrower of its determination of the Applicable Margin. The new Applicable Margin as so determined by the Bank shall be effective as to all then outstanding LIBOR Advances and all new LIBOR Advances thereafter made, and such new Applicable Margin shall remain in effect through the next date upon which the determination of a new Applicable Margin becomes effective in accordance with the above provisions. Notwithstanding the foregoing, upon any Event of Default, the Applicable Margin with respect to the Revolving Line of Credit Loan shall be 4.25% and the Applicable Margin with respect to the Term Loan shall be 3.75%.”

(b) Section III.A.14 of the Loan Agreement shall be, and hereby is, deleted in its entirety and replaced with the following new Section III.A.14:

“14. Prime Rate . The term “Prime Rate” means the variable per annum rate of interest so designated from time to time by Bank as its prime rate plus the Applicable Margin. The Bank’s prime rate is a reference rate and does not necessarily represent the lowest or best rate being charged to any customer. Changes in the Prime Rate resulting from changes in the Bank’s prime rate shall take place immediately without notice or demand of any kind.”

(c) Section III.A.16 of the Loan Agreement shall be, and hereby is, added a new section of the Loan Agreement immediately after Section III.A.15 of the Loan Agreement:

“16. LIBOR Definitions for LIBOR Advantage Program . Revolving Credit Advances to the Borrower under the Bank’s automated sweep program shall bear interest under, and in accordance with, the Bank’s LIBOR Advantage Program. The Bank shall designate all Revolving Credit Advances which are subject to the LIBOR Advantage Program. Notwithstanding anything to the contrary in this Agreement, including the provisions of Section III.B. hereof regarding selection of interest rates, automatic Revolving Credit Advances to the Borrower under the Bank’s automated sweep program are subject to the provisions of the Bank’s LIBOR Advantage Program and do not require any notice from Borrower. Notwithstanding the definitions set forth in this Section III.A., solely for purposes of such Revolving Credit Advances under the LIBOR Advantage Program, the following definitions shall apply in lieu of the definitions provided for such terms set forth above in this Section III.A.:

“ Interest Payment Date ” means (a) as to any Prime Rate Advance, the first Business Day of each January, April, July, and October while such Advance is outstanding, and (b) as to any LIBOR Advance under the LIBOR Advantage Program, initially, June 26, 2009, and thereafter the day of each succeeding month which numerically corresponds to such date or, if a month does not contain a day that numerically corresponds to such date, the Interest Payment Date shall be the last day of such month.

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“ Interest Period ” means with respect to each LIBOR Advance under the LIBOR Advantage Program, the period commencing on (and including) June 26, 2009 (the “Start Date”) and ending on (but excluding) the date which numerically corresponds to such date one (1) month later, and thereafter, each one (1) month period ending on the day of such month that numerically corresponds to the Start Date. If an Interest Period with respect to a LIBOR Advance under the LIBOR Advantage Program i