EXHIBIT 10(N)

                 SECOND AMENDMENT TO SECOND AMENDED AND RESTATED

                       REVOLVING CREDIT SECURITY AGREEMENT

         This Second  Amendment to Second Amended and Restated  Revolving Credit
and Security Agreement (the "Amendment") is made this 5th day of December, 2006,
by and among COMPUDYNE CORPORATION, a Nevada corporation ("CompuDyne"), TIBURON,
INC., a Virginia  corporation  (formerly  known as  Compudyne - Public  Safety &
Justice,  Inc., a Virginia  corporation)  ("Tiburon"),  NORMENT  SECURITY GROUP,
INC., a Delaware  corporation  ("Norment"),  NORSHIELD  CORPORATION,  an Alabama
corporation  ("Norshield"),  FIBER  SENSYS,  LLC, a Delaware  limited  liability
company ("Fiber"),  COMPUDYNE - INTEGRATED ELECTRONICS DIVISION, LLC, a Delaware
limited liability company ("CompuDyne  Integrated"),  CORRLOGIC, LLC, a Delaware
limited  liability  company  ("CorrLogic"),   XANALYS  CORPORATION,  a  Delaware
corporation  ("Xanalys"),  and SIGNAMI DCS,  LLC, a Delaware  limited  liability
company ("Signami") (CompuDyne,  Tiburon, Norment,  Norshield,  Fiber, CompuDyne
Integrated,  CorrLogic, Xanalys and Signami, each a "Borrower", and collectively
"Borrowers"), the financial institutions which are now or which hereafter become
a party hereto (collectively, the "Lenders" and individually a "Lender") and PNC
BANK, NATIONAL ASSOCIATION ("PNC"), as agent for Lenders (PNC, in such capacity,
the "Agent").

                                   BACKGROUND

         A. On December 19, 2005,  Borrowers,  Lenders and Agent  entered  into,
inter alia, a certain Second Amended and Restated  Revolving Credit and Security
Agreement  (as same has been or may be  amended,  modified,  renewed,  extended,
replaced,  or substituted from time to time, the "Loan  Agreement"),  to reflect
certain financing  arrangements  between the parties thereto. The Loan Agreement
and all other  documents  executed  in  connection  therewith  are  collectively
referred to as the "Existing  Financing  Agreements." All capitalized  terms not
otherwise  defined  herein shall have the meaning  ascribed  thereto in the Loan
Agreement.  In the case of a direct conflict  between the provisions of the Loan
Agreement and the  provisions of this  Amendment,  the  provisions  hereof shall
prevail.

         B. The  Borrowers  have  requested  and the Agent and the Lenders  have
agreed to modify the Loan Agreement.

         C. The parties have agreed, subject to the terms and conditions of this
Amendment, to modify and amend the Loan Agreement.

NOW THEREFORE,  WITH THE FOREGOING BACKGROUND HEREINAFTER DEEMED INCORPORATED BY
REFERENCE  HEREIN AND MADE PART  HEREOF,  THE PARTIES  HERETO,  INTENDING  TO BE
LEGALLY BOUND, PROMISE AND AGREE AS FOLLOWS:
                  Amendment to Loan Agreement. Upon the Effective Date, the Loan
Agreement  shall be amended by deleting the  definition of  "Revolving  Interest
Rate" and replacing same as follows:

                  "REVOLVING  INTEREST  RATE"  SHALL MEAN AN  INTEREST  RATE PER
ANNUM EQUAL TO (A) THE  ALTERNATE  BASE RATE WITH RESPECT TO DOMESTIC RATE LOANS
AND (B) THE SUM OF THE EURODOLLAR  RATE PLUS TWO PERCENT (2.00%) WITH RESPECT TO
EURODOLLAR RATE LOANS.
                  Omnibus  Amendment  to Loan  Agreement  and  Other  Documents.
Borrowers hereby confirm and acknowledge that any and all references in the Loan
Agreement and the Other  Documents to Compudyne - Public Safety & Justice,  Inc.
shall mean and include Tiburon, Inc., a Virginia corporation.

                  Reaffirmation. Each Borrower hereby:

                       reaffirms all representations and warranties made to
Agent  and  Lenders  under  the Loan  Agreement  and all of the  other  Existing
Financing  Agreements and confirms that all are true and correct in all material
respects  as of the date hereof  (except to the extent any such  representations
and  warranties  specifically  relate to a  different  date,  in which case such
representations  and  warranties  shall  be true  and  correct  in all  material
respects on and as of such other specific date);

                       reaffirms  all of the  covenants  contained in the Loan
Agreement,  covenants to abide thereby until all Advances, Obligations and other
liabilities  of  Borrowers  to Agent and  Lenders  under the Loan  Agreement  of
whatever nature and whenever  incurred,  are satisfied  and/or released by Agent
and Lenders; and

                       Except as  modified by the terms  hereof,  all of the
other terms and conditions of the Loan Agreement,  as amended,  and all other of
the Existing  Financing  Agreements are hereby  reaffirmed and shall continue in
full force and effect as therein written.


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<PAGE>

                  Representations and Warranties.  Each Borrower hereby:

                       represents  and  warrants  that no Default or Event of
Default has  occurred  and is  continuing  under any of the  Existing  Financing
Agreements;

                       except as modified hereby,  represents and warrants that
it has the authority and legal right to execute, deliver and carry out the terms
of this  Amendment,  that such actions  were duly  authorized  by all  necessary
corporate or limited  liability  company action and that the officers  executing
this Amendment on its behalf were similarly  authorized and empowered,  and that
this   Amendment   does  not  contravene  any  provisions  of  its  articles  of
incorporation or by-laws, or certificate of formation or operating agreement, as
applicable,  or other  formation  documents,  or of any contract or agreement to
which it is a party or by which any of its properties are bound; and

                       represents and warrants that this Amendment and all
assignments,  instruments,  documents,  and agreements executed and delivered in
connection herewith, are valid, binding and enforceable in accordance with their
respective terms.

                  Conditions Precedent/Effectiveness  Conditions. This Amendment
shall be effective  upon  satisfaction  of the  following  conditions  precedent
("Effective  Date") (all documents to be in form and substance  satisfactory  to
Agent and Agent's counsel):

                       Agent shall have received this Amendment fully executed
by Borrowers; and

                       Agent shall have received such other agreements,
documents or information as requested by Agent in its sole discretion.

                  Further  Assurances.  Each Borrower  hereby agrees to take all
such  actions  and to  execute  and/or  deliver  to Agent and  Lenders  all such
documents,  assignments,  financing statements and other documents, as Agent and
Lenders may  reasonably  require from time to time, to effectuate  and implement
the purposes of this Amendment.

                  Payment of Expenses.  Borrowers  shall pay or reimburse  Agent
and Lenders for its reasonable  attorneys'  fees and expenses in connection with
the  preparation,  negotiation and execution of this Amendment and the documents
provided for herein or related hereto.

                  Confirmation   of   Obligations.    Borrowers'   confirm   and
acknowledge  that  as of the  close  of  business  on  November  27,  2006,  the
outstanding Obligations consist of (i) $0 of Revolving Advances, (ii) issued and
outstanding   Letters  of  Credit  in  the  Maximum   Undrawn  Amount  equal  to
$3,169,035.61  and (iii)  all  fees,  costs  and  expenses  incurred  to date in
connection with the Loan Agreement and the Other Loan Documents.

                  Miscellaneous.

                       Third Party Rights. No rights are intended  to be created
hereunder  for the benefit of any third party  donee,  creditor,  or  incidental
beneficiary.

                       Headings.  The  headings  of any  paragraph  of  this
Amendment  are for  convenience  only and  shall  not be used to  interpret  any
provision hereof.

                       Modifications.   No   modification   hereof   or  any
agreement  referred to herein shall be binding or enforceable  unless in writing
and signed on behalf of the party against whom enforcement is sought.

                       Governing Law. The terms and conditions of this Amendment
shall be governed by the laws of the Commonwealth of Pennsylvania.

                       Counterparts.  This  Amendment may be executed in any
number of counterparts and by facsimile, each of which when so executed shall be
deemed to be an original and all of which taken  together  shall  constitute one
and the same agreement.



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         IN WITNESS  WHEREOF,  the  parties  have caused  this  Amendment  to be
executed and  delivered by their duly  authorized  officers as of the date first
above written.

                                     COMPUDYNE CORPORATION

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:    Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Chief Financial Officer, Treasurer
                                           -------------------------------------

                                     TIBURON, INC.

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:     Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Treasurer,  Vice President
                                           -------------------------------------

                                     NORSHIELD CORPORATION

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:    Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Treasurer,  Vice President
                                           -------------------------------------

                                     FIBER SENSYS, LLC

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:    Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Treasurer,  Vice President
                                           -------------------------------------

                                     COMPUDYNE -
                                     INTEGRATED ELECTRONICS DIVISION, LLC

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:    Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Vice President
                                           -------------------------------------

     [Signature Page 1 of 2 (Second Amendment To Second Amended And Restated
                     Revolving Credit Security Agreement)]


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<PAGE>

                                     CORRLOGIC, LLC

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:    Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Treasurer,  Vice President
                                           -------------------------------------

                                     NORMENT SECURITY GROUP, INC.

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:    Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Treasurer,  Vice President
                                           -------------------------------------

                                     XANALYS CORPORATION

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:    Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Treasurer,  Vice President
                                           -------------------------------------

                                     SIGNAMI DCS, LLC

                                     By:      /s/ Geoffrey F. Feidelberg
                                        ----------------------------------------
                                     Name:    Geoffrey F. Feidelberg
                                          --------------------------------------
                                     Title:   Vice President
                                           -------------------------------------



                                     PNC BANK, NATIONAL ASSOCIATION,
                                     as Lender and as Agent

                                     By:      /s/ James P. Sierakowski
                                        ----------------------------------------
                                           James P. Sierakowski, Vice President





     [Signature Page 2 of 2 (Second Amendment To Second Amended And Restated
                     Revolving Credit Security Agreement)]




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