Exhibit 10(a)


                                  AMENDMENT TO
                    AMENDED AND RESTATED EMPLOYMENT AGREEMENT

     Amendment  ("Amendment")  dated as of August 31,  2000 to the  Amended  and
Restated  Employment  Agreement  ("Employment  Agreement"),  entered  into as of
January 1, 1998, by and between Merrimac Industries,  Inc. ("Company") and Mason
N. Carter ("Executive").

     WHEREAS,  the  Company  and  the  Executive  entered  into  the  Employment
Agreement; and

     WHEREAS,  the Board of Directors of the Company and the Executive  agree to
amend the Employment Agreement as set forth herein;

     NOW,  THEREFOR,  in  consideration  of the premises set forth  herein,  the
mutuality and sufficiency of which are hereby acknowledged, the parties agree as
follows:

     1. Section 2 of the Employment  Agreement is hereby amended and restated by
deleting the phrase "this  Agreement  will  commence on the date hereof and will
end on December 31, 2002 (the "Initial Term"), and will automatically  renew for
successive twelve month periods  commencing  January 1, 2003" and replacing with
the following:

     "this  Agreement  will commence on the date hereof and will end on December
31, 2007 (the  'Initial  Term'),  and will  automatically  renew for  successive
twelve month periods commencing January 1, 2008."

     2. Section 5 of the Employment  Agreement is hereby amended by adding a new
Section 5(g) to the end of existing Section 5(f) as follows:

     "5(g)  Provided  the  Executive's  employment  with  the  Company  has  not
terminated  for  Cause or by  resignation,  on the 31st day of August of each of
2001, 2002, 2003, 2004 and 2005 ('Bonus Date'),  the Executive shall be entitled
to receive, on each Bonus Date, a special bonus ('Special Bonus') which shall be
payable  in the form of  forgiveness  of a portion of the  principal  of and the
interest on the Promissory Note (the 'Note'), dated August 31, 2000, executed by
the Executive to the order of the Company,  the form of which is attached hereto
as Appendix A. Each annual Special Bonus shall be in the sum of (i) $56,000 plus
(ii) an amount  equal to the accrued and unpaid  interest on the Note during the
twelve month period ending on the Bonus Date.  Notwithstanding the foregoing, in
the event the Executive's  employment  shall  terminate by reason of death,  his
personal representative may elect to accelerate the forgiveness of the Note into
a single  lump sum and if by reason  of  disability  each  Special  Bonus  shall
continue to be payable on the dates set forth above.  It shall be a condition to
the  payment  of  each  Special   Bonus  that  the  Executive  or  his  personal
representative shall deliver a good check in the amount of any withholding taxes
due in respect thereof."

     3. Capitalized terms not otherwise defined in this Amendment shall have the
meanings indicated in the Employment Agreement.

     4. This Amendment may be executed in any number of counterparts and each of
such  counterparts  shall for all purposes be deemed to be an original,  and all
such counterparts shall together constitute but one and the same instrument.

     5. This Amendment shall be effective as of the date hereof,  and, except as
amended  hereby,  all of the terms and  provisions of the  Employment  Agreement
shall remain in full force and effect.


     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
and year first above written.

                                         MERRIMAC INDUSTRIES, INC.

                                         By:   /s/ Robert V. Condon
                                               --------------------
                                               Name: Robert V. Condon
                                               Title:  Vice President, Finance

                                               /s/ Mason N. Carter
                                               -------------------
                                                   Mason N. Carter
<PAGE>


                                                                   Appendix A

                                PROMISSORY NOTE



U.S. $280,000                                        West Caldwell, New Jersey
                                                               August 31, 2000

     FOR VALUE  RECEIVED,  MASON N.  CARTER  ("Payor"),  hereby  unconditionally
promises to pay, in accordance  with the terms of this  promissory  note (as the
same may be amended from time to time, this "Promissory  Note"), to the order of
MERRIMAC  INDUSTRIES,  INC., a New Jersey  corporation,  or its  successors  and
assigns  ("Note  Holder"),  in lawful  money of the United  States of America in
immediately  available  funds,  on August 31, 2005 and in such account,  at such
place,  or to such party as Note Holder may designate in writing,  the principal
amount of Two  Hundred  Eighty  Thousand  Dollars  (U.S.  $280,000).  Payor also
unconditionally  promises to pay  interest  annually  in arrears  (as  specified
below) on the unpaid  principal  amount of this Promissory Note outstanding from
time to time at a variable rate equal to the rate  announced  publicly from time
to time during such period by Note  Holder's  primary  lending bank  (currently,
Summit  Bancorp)  as its prime rate (with  changes in the  interest  rate hereon
being effective on the date of each announced change in such prime rate.

     Interest on the unpaid principal amount of this Promissory Note outstanding
from time to time shall  accrue from the date hereof and shall be paid  annually
in arrears on the 31st day of August of each of 2001, 2002, 2003, 2004 and 2005.

     Payor may, at his option, prepay all or, from time to time, any part of the
unpaid principal balance of this Promissory Note, together with interest accrued
thereon, without payment of any premium or penalty.

     Payor hereby  waives  presentment,  demand,  notice,  protest and all other
demands and notices in connection  with the delivery,  acceptance,  performance,
default or enforcement of this Promissory Note.

     If Payor's employment with Note Holder is terminated by reason of cause (as
defined in the Amended and Restated Employment Agreement, dated January 1, 1998,
between Payor and Note Holder) or resignation,  then Note Holder, at its option,
by  written  notice to Payor may  declare  the entire  principal  amount of this
Promissory Note to be due and payable,  together with accrued interest  thereon,
without other notice,  demand,  presentment or protest,  all of which are hereby
waived by Payor.

     Payor shall not assign this Promissory  Note or his  obligations  hereunder
without the prior written consent of Note Holder.  This Promissory Note shall be
binding upon Payor and his  permitted  assigns and shall inure to the benefit of
Note Holder and its successors and assigns.

     This  Promissory  Note has been  executed and delivered in the State of New
Jersey and shall be governed by, and  construed  and  interpreted  in accordance
with,  the internal laws of the State of New Jersey without giving effect to any
conflicts  of  laws  provisions  of  such  State.  Payor  hereby  expressly  and
irrevocably agrees and consents that any suit, action, or proceeding arising out
of or relating to this Promissory Note may be instituted in any State.


                                                          /s/ Mason N. Carter
                                                          -------------------
                                                              Mason N. Carter