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                                                                   EXHIBIT 10.10

              WAIVER AND THIRD AMENDMENT TO PARTICIPATION AGREEMENT

         This Waiver and Third Amendment to Participation Agreement (this "Third
Amendment"), dated as of February 24, 2000, is entered into among REMEC, INC., a
California corporation, as Lessee; UNION BANK OF CALIFORNIA, N.A., not in its
individual capacity except as expressly stated herein but solely as Certificate
Trustee; the Persons named on Schedule I-A of the Participation Agreement
(together with their respective permitted successors, assigns and transferees),
as Certificate Purchasers; the Persons listed on Schedule I-B of the
Participation Agreement (together with their respective permitted successors,
assigns and transferees), as Lenders; and UNION BANK OF CALIFORNIA, N.A., as
Agent.

                              W I T N E S S E T H:

         WHEREAS, Lessee, Lessor, Agent, the Certificate Purchasers and the
Lenders have entered into that certain Participation Agreement, dated as of
August 25, 1998 (as amended by those certain First and Second Amendments to
Participation Agreement, dated as of September 29, 1998 and September 21, 1999,
respectively, the "Participation Agreement") (capitalized terms used herein
without definition shall have the meanings ascribed to them in Appendix 1 to the
Participation Agreement, except as modified pursuant to Section 3 below); and

         WHEREAS, the parties hereto desire to enter into this Third Amendment
in order to amend the Participation Agreement and Appendix 1 thereto to modify
certain terms in those documents with respect to the matters provided for in
this Third Amendment.

         NOW, THEREFORE, in consideration of the foregoing premises, the mutual
terms and conditions herein contained, and for other good and valuable
consideration the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

         Section 1. Waiver. Lessor, Agent and each of the Participants hereby
(a) waive, for the fiscal quarter of Lessee ended October 31, 1999, and only for
such fiscal quarter, compliance with (i) the Funded Debt to EBITDA ratio
requirement set forth in Section 5.11 of the Participation Agreement, (ii) the
restrictions on loans or advances to Affiliates and Subsidiaries set forth in
Section 5.19 of the Participation Agreement, and (iii) the limitation on
quarterly losses set forth in Section 5.23 of the Participation Agreement, and
(b) agree that such noncompliance shall not constitute a Lease Default or a
Lease Event of Default. The waiver here given is specific to the covenants, and
for the fiscal quarter of Lessee, referred to above and shall not operate as a
waiver of compliance by Lessee with any other covenants set forth in the
Participation Agreement, or with the covenants set forth above for any other
fiscal quarter of Lessee.

         Section 2. Modifications to Participation Agreement. The parties hereto
amend the Participation Agreement as follows and all references to the words
"Participation Agreement" shall hereinafter refer to the Participation Agreement
as amended by this Section 2 and by Section 3 below:

                 2.1 Section 2.15 of the Participation Agreement is amended and
restatedin its entirety to read as follows:

                  SECTION 2.15. Collateralization. Lessee shall at all times
         cause its obligations under the Lessee Guarantee to be collateralized
         to the extent and in the manner provided in this Section 2.15.

                           (a) Lessee shall cause its obligations under the
         Lessee Guarantee to be collateralized with Liquid Assets which
         constitute Permitted Investments and have an aggregate Current Value of
         not less than the Lease Balance until such time as Lessee has delivered
         to

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                  Agent on behalf of Lessor and each of the Participants a
                  quarterly or annual financial statement of Lessee as required
                  by Section 5.6(a) or Section 5.6(b) of the Participation
                  Agreement, as the case may be, which reflects that (i) as at
                  the end of each of the four (4) consecutive fiscal quarters of
                  Lessee most recently ended, Lessee has maintained (A) a
                  Tangible Net Worth of not less than the sum of (1) One Hundred
                  Sixty-five Million Dollars ($165,000,000), (2) ninety percent
                  (90%) of Lessee's net profit after taxes for each fiscal
                  quarter of Lessee ending after October 31, 1999 and on or
                  before the date of computation, and (3) one hundred percent
                  (100%) of the net proceeds of any equity securities issued by
                  Lessee on or after November 1, 1999, (B) a ratio of Funded
                  Debt to EBITDA of not more than 1.5:1.0, (C) a ratio of cash,
                  accounts receivable and marketable securities to current
                  liabilities of not less than 1.5:1.0, as such terms are
                  defined by GAAP, and (D) a ratio of EBITDA, plus Rent and all
                  operating and capital lease payments, for the twelve (12)
                  month period preceding the date of calculation to Fixed
                  Charges of not less than 2.0:1.0, and (ii) for each of the
                  four (4) consecutive fiscal quarters of Lessee most recently
                  ended, Lessee has achieved an operating profit of not less
                  than Two Million Two Hundred Fifty Thousand Dollars
                  ($2,250,000).

                           (b) From and after Lessee's delivery to Agent of the
                  financial statement referred to in Section 2.15(a), Lessee
                  shall cause its obligations under the Lessee Guarantee to be
                  collateralized with Liquid Assets which constitute Permitted
                  Investments and have an aggregate Current Value of not less
                  than Six Million Dollars ($6,000,000).

                           (c) The collateralization required by this Section
                  2.15 shall operate to reduce the Applicable Margin as and to
                  the extent provided in the definition of such term which is
                  set forth in Appendix 1 to the Participation Agreement.

                  2.2 Section 5.8 of the Participation Agreement is amended and
restated in its entirety to read as follows:

                  SECTION 5.8. Tangible Net Worth. Lessee will at all times
         maintain a Tangible Net Worth of not less than the sum of (a) One
         Hundred Sixty-five Million Dollars ($165,000,000), (b) ninety percent
         (90%) of Lessee's net profit after taxes for each fiscal quarter of
         Lessee ending after October 31, 1999 and on or before the date of
         computation, and (c) one hundred percent (100%) of the net proceeds of
         any equity securities issued by Lessee on or after November 1, 1999.

                  2.3 Section 5.9 of the Participation Agreement is hereby
deleted in its entirety.

                  2.4 Section 5.11 of the Participation Agreement is amended and
restated in its entirety to read as follows:

                  SECTION 5.11. Funded Debt to EBITDA. Lessee will maintain a
         ratio of Funded Debt to EBITDA of not more than (a) as at the end of
         the fiscal quarter of Lessee ending January 31, 2000, 2.50:1.00, (b) as
         at the end of the fiscal quarter of Lessee ending April 30, 2000,
         2.00:1.00, and (c) as at the end of the fiscal quarter of Lessee ending
         July 31, 2000, and at all times thereafter, 1.5:1.0.

                  2.5 The second sentence of Section 5.18 of the Participation
Agreement is hereby amended to read as follows:

         Lessee will not, and will not permit any Subsidiary to, borrow any
         money, become contingently liable to borrow money, or enter any
         agreement to directly or indirectly obtain borrowed money, except
         pursuant to agreements made with UBOC, except for loans and other
         borrowings secured by liens permitted by Section 5.2 and except for
         obligations incurred by AirTech under the foreign exchange and shipside
         bond facilities of AirTech referred to in Section 5.19(a)(iv).

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                  2.6 Section 5.19 of the Participation Agreement is amended and
restated in its entirety to read as follows:

                  SECTION 5.19. Loans, Advances and Guaranties. Lessee will not,
         and will not permit any Subsidiary to, except in the ordinary course of
         business as currently conducted, make any loans or advances, become a
         guarantor or surety, pledge its credit or properties in any manner or
         extend credit; provided, however, that (a) Lessee may (i) make loans or
         advances to its Affiliates or Subsidiaries, (ii) make a loan to
         SkyOnline Inc. (formerly known as Direct-to-Phone International, Inc.)
         ("SkyOnline") in a principal amount not to exceed Five Million Dollars
         ($5,000,000), (iii) guarantee the obligations of AirTech referred to in
         Section 5.19(b), and (iv) guarantee the obligations of AirTech to
         Lloyds Bank arising under the foreign exchange facility in an amount
         not to exceed Five Hundred Thousand Pounds Sterling (GBP500,000) and
         the shipside bond facility in an amount not to exceed One Hundred
         Thousand Pounds Sterling (GBP100,000) which are presently provided to
         AirTech by Lloyds Bank, and (b) AirTech may (i) provide E-Plus
         Mobilfunk GmbH with a contract performance bond in an amount not to
         exceed One Million Seven Hundred Fifty Thousand German Marks
         (DM1,750,000) and with an expiry of not later than June 30, 2000, and
         (ii) provide Bouygues Telecom SA with a contract performance bond in an
         amount not to exceed Four Million Seven Hundred Thousand French Francs
         (FF4,700,000) and with an expiry of not later than December 31, 2000.

                  2.7 Section 5.20(b) of the Participation Agreement is amended
and restated in its entirety to read as follows:

         (b) Lessee's purchase of preferred stock in SkyOnline in the amount of
    Four Million Six Hundred Thousand Dollars ($4,600,000).

                  2.8 Section 5.23 of the Participation Agreement is amended and
restated in its entirety to read as follows:

                  SECTION 5.23. Profitability. Lessee will not (a) incur a
         cumulative net loss for any two or more consecutive fiscal quarters
         (commencing with the two fiscal quarter period of Lessee ending April
         30, 2000), and (b) incur a net loss for any fiscal year (commencing
         with the fiscal year of Lessee ending January 31, 2001).

         Section 3. Modifications to Appendix 1. The parties hereto hereby amend
Appendix 1 to the Participation Agreement as follows, and all references to
"Appendix 1" or "Appendix 1 to the Participation Agreement" or "Appendix 1 to
that certain Participation Agreement. . ." (and whether or not identifying the
parties thereto) shall hereinafter refer to Appendix 1 as amended hereby:

                  3.1 The final two (2) sentences of the definition of the term
"Applicable Margin" are hereby amended and restated as follows:

         Notwithstanding the foregoing, for any day during an Interest Period
         with respect to the portion of the outstanding principal amount of the
         Loans which, on such day, are collateralized pursuant to the Pledge
         Agreement with Liquid Assets which constitute Permitted Investments,
         the Applicable Margin for such day shall be 0.75% (75 basis points).
         For purposes of the foregoing sentence (a) the portion of the
         outstanding principal amount of the Loans which is so collateralized
         shall be determined by multiplying (i) the aggregate outstanding
         principal amount of the Loans by (ii) a fraction, the numerator of
         which is the Current Value (as defined in the Pledge Agreement) of the
         Liquid Assets which have so been pledged and the denominator of which
         is the Lease Balance, and (b) the portion of the outstanding principal
         amount of any given Lender's Loan which is so collateralized shall be
         determined by multiplying (i) the outstanding principal amount of such
         Lender's Loan by (ii) the fraction more particularly described in
         clause (a)(ii) of this sentence.

                  3.2 The definition of the term "Custodial Agreement" is hereby
deleted in its entirety.

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                  3.3 The definition of the term "Operative Documents" is hereby
amended by adding to the end of such definition the phrase ", including without
limitation, the Pledge Agreement."

                  3.4 A definition of the term "Pledge Agreement" is hereby
added immediately following the definition of the term "Plan", said definition
to read as follows:

                  "Pledge Agreement" shall mean a Security Agreement (Investment
         Securities) by Lessee in favor of Agent (both individually and as
         Agent), the Certificate Purchasers, the Lenders and each of their
         respective successors and assigns, in form and substance satisfactory
         to Agent and the Participants, under which Lessee pledges Liquid Assets
         as collateral for Lessee's obligations under the Lessee Guarantee.

         Section 4. Representations and Warranties. Lessee represents and
warrants to each of the other parties hereto that each of the representations
and warranties of Lessee contained in the Participation Agreement and in each
other Operative Document is true and correct in all material respects on the
date hereof, with the same effect as though made on and as of such date and, for
purposes of this paragraph, all references in such representations and
warranties to the "Operative Documents" shall be deemed to include this Third
Amendment.

         Section 5. Effectiveness. This Third Amendment shall become effective
on the date on which Agent, on behalf of itself, Lessor and each of the
Participants, shall have received the following, each in form and substance
satisfactory to Agent, Lessor and each of the Participants:

         (a) This Third Amendment, duly executed by each of the parties hereto;

         (b) The Pledge Agreement, dated the date of this Third Amendment, duly
executed by Lessee;

         (c) Evidence that all steps necessary in the opinion of Agent to
perfect the security interest granted by Lessee pursuant to the Pledge Agreement
have been duly taken; and

         (d) Such other documents and agreements as Agent or any Participant may
reasonably require to effectuate the intent and purpose of this Third Amendment
and to establish the accuracy and completeness of the representations and
warranties, and compliance with the terms and conditions, contained in this
Third Amendment, the Participation Agreement and the other documents,
instruments and agreements entered into in connection herewith and therewith.

         Section 6. Applicable Law. THIS THIRD AMENDMENT HAS BEEN DELIVERED IN,
AND SHALL IN ALL RESPECTS BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE
LAWS OF, THE STATE OF CALIFORNIA, WITHOUT REGARD TO CONFLICTS OF LAW PRINCIPLES
OF SUCH STATE.

         Section 7. Counterparts. This Third Amendment may be executed in any
number of counterparts and by different parties hereto on separate counterparts,
each executed counterpart constituting an original but all together one
agreement.

         Section 8. Direction to Trustee. By signing this Third Amendment, the
Participants authorize and direct Union Bank of California, N.A., as Certificate
Trustee, and Union Bank of California, N.A., as Agent, to sign this Third
Amendment.

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         IN WITNESS WHEREOF, the parties hereto have caused this Third Amendment
to be executed and delivered as of the date first above written.

Lessee:                  REMEC, INC., a California corporation, as Lessee

                         By:______________________________________
                         Name Printed: Mike McDonald
                         Title: Chief Financial Officer

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Certificate Trustee:     UNION BANK OF CALIFORNIA, N.A., not in its individual
                         capacity except as expressly stated herein, but solely
                         as Certificate Trustee

                         By:____________________________________
                         Name Printed: Andrew R. Ball
                         Title: Vice President

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Agent:            UNION BANK OF CALIFORNIA, N.A., not in its individual capacity
                  except as expressly stated herein, but solely as Agent

                  By:____________________________________
                  Name Printed: Rick Young
                  Title: Vice President

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Certificate Purchaser:  BANKERS COMMERCIAL CORPORATION, as Certificate Purchaser


                        By:____________________________________
                        Name Printed: Lance B. Markowitz
                        Title: President

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Lender:           UNION BANK OF CALIFORNIA, N.A., not in its individual capacity
                  except as expressly stated herein, but solely as Lender

                  By:____________________________________
                  Name Printed: Rick Young
                  Title: Vice President

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