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                                  EXHIBIT 10dd

              AMENDMENT NO. 2 TO AND WAIVER OF AMENDED AND RESTATED
                     REVOLVING CREDIT AND SECURITY AGREEMENT


         AMENDMENT NO. 2 AND WAIVER dated as of April 16, 2001, by and among
MARLTON TECHNOLOGIES, INC., a New Jersey corporation ("Marlton"), and certain
subsidiaries executing this Amendment as Borrowers (together with Marlton,
collectively, the "Borrowers") and FIRST UNION NATIONAL BANK, a national banking
association, as Bank (the "Bank") and as Agent (the "Agent").

         WHEREAS, the Borrowers, the Agent and the Banks entered into a certain
Amended and Restated Revolving Credit and Security Agreement dated as of January
21, 2000 (as amended on the date hereof and hereafter, the "Credit Agreement");
capitalized terms not otherwise defined herein having the meanings set forth in
the Credit Agreement; and

         WHEREAS, the parties wish to amend certain provisions of the Credit
Agreement;

         NOW THEREFORE, in consideration of the mutual agreements herein
contained, the parties hereto, intending to be legally bound, hereby agree as
follows, effective on the date first above written.

         1. Facility Amount. The "Background" section of the Credit Agreement
shall be amended to reduce the amount of the Facility from $30 million to $25
million and to eliminate any reference to a possible increase in the Facility to
$35 million.

         2. Definitions. Section 1.1 shall be amended as follows:

(a)  "Applicable Margin" shall be amended in full as follows:


       "Applicable Margin" means, in accordance with the table and text below:


                                              Applicable Margin:


       If the ratio of Funded                 LIBOR Loans and         Base
       Debt to EBITDA is:                     Letter of Credit Fees:  Rate Loans
       -----------------                      ---------------------   ----------

       higher than 2.50:1 (it being                  2.75%              0.75%
       acknowledged that the maximum
       permitted ratio of Funded Debt to
       EBITDA may never exceed
       the amount permitted under
       Section 6.25)

       2.50:1 or lower, but higher than 2.25:1       2.25%              0.25%

       2.25:1 or lower                               2.00%              0.00%


                  The calculation of the Applicable Margin pursuant to the above
                  tables shall be made quarterly, based upon the Interim
                  Financial Statements or Financial Statements, as applicable,
                  of MTI and its Subsidiaries as at the last day of each such
                  fiscal quarter and for the fiscal period then ended. In the
                  event that the Applicable Margin changes, such change shall
                  become effective for Eurodollar Loans then existing or
                  thereafter made, as of the first day of the fiscal quarter
                  immediately following the date on which such financial
                  statements are delivered to the


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                Agent. In the event that such financial statements are not
                delivered to the Agent on or before the date required under
                this Agreement, the Applicable Margin shall be calculated as
                if the Funded Debt to EBITDA is greater than 2.50:1, effective
                upon the last day of the fiscal quarter to which such
                financial statements relate, and until such financial
                statements are delivered showing that the Borrowers are
                entitled to a lower rate hereunder.

(b)  The definition of "Maturity Date" shall be amended to read in full as
     follows:

                "Maturity Date" means, unless the Loans are earlier
                accelerated pursuant to Section 7.2., the date which is the
                fourth (4th) anniversary of the Closing Date.

(c)  "Revolving Credit Commitment" shall be amended to read in full as follows:

                "Revolving Credit Commitment" means $25,000,000, as such
                amount may be reduced pursuant to Section 2.1(D) hereof.

                3. Revolving Credit Commitment. Section 2.1 shall be amended
       to delete Section 2.1(B) and subsection (B) shall be intentionally
       blank.

                4. Loans, Investment and Contingent Liabilities. Section
       6.13(B)(4) shall be deleted.

                5. Restriction on Acquisitions; Mergers; Corporate Structure.
       Section 6.16(A)(iii) and Section 6.16(B) shall be deleted.

                6. Minimum Net Worth. Section 6.24 shall be amended to read in
       full as follows:

                SECTION 6.24 Minimum Net Worth. MTI will maintain at the end
                of each fiscal quarter, commencing the fiscal quarter ending
                June 30, 2001, consolidated Net Worth in an amount not less
                than $28,000,000 plus 50% of MTI's cumulative consolidated net
                income for the fiscal year ending December 31, 2001 and each
                fiscal year thereafter. For purposes of determining the
                required minimum as aforesaid (a) cumulative consolidated net
                income shall include consolidated net income for entire fiscal
                years only and shall be determined by reference to the
                financial statements delivered under Section 6.1, and (b) a
                consolidated net loss during any period shall be deemed to be
                consolidated net income in the amount of zero.

                7. Senior Funded Debt to EBITDA Ratio. Section 6.25 shall be
       deleted.

                8. Funded Debt to EBITDA Ratio. Sections 6.26 and 6.27 shall
       be renumbered and shall be referred to as Sections 6.25 and 6.26,
       respectively, and Section 6.25 shall read in full as follows:

                SECTION 6.25 Funded Debt to EBITDA Ratio. The Borrowers will
                not permit the ratio of Funded Debt, determined as of the last
                day of each period of four consecutive fiscal quarters of MTI,
                to EBITDA for such period, to be greater than: 3.25:1.00 at
                June 30, 2001 and at September 30, 2001: 3.00:1.00 at December
                31, 2001; and 2.75:1.00 thereafter.

                9. Waivers. The Agent and the Banks hereby waive compliance by
         the Borrowers with Section 6.24 Minimum Net Worth and Section 6.25 (as
         renumbered above Funded Debt to EBITDA ratio for the fiscal quarters
         ending December 31, 2000 and March 31, 2001.


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                10. Representations and Covenants. The Borrowers hereby
       represent, warrant and certify that, assuming the effectiveness of
       Paragraph 9 of this Amendment: (a) all representations and warranties
       contained in the Credit Agreement, including without limitation the
       schedules thereto (updated as attached hereto), are true, correct and
       complete on and as of the date hereof, (b) all covenants and agreements
       made in the Credit Agreement have been complied with and fulfilled, (c)
       no Default or Event of Default is in existence on the date hereof, and
       (d) this Amendment has been duly authorized, executed and delivered by
       each Borrower and is the legal, valid and binding obligation of each of
       the Borrowers, enforceable in accordance with its terms.

                11. Ratification. Other than as specifically set forth herein,
       the Borrowers hereby ratify and confirm the Credit Agreement and all
       instruments and agreements relating thereto, and confirm that (a) all
       of the foregoing remain in full force and effect, (b) each of the
       foregoing is enforceable against the Borrowers in accordance with its
       terms, and (c) Borrowers have no defenses to its obligations or claims
       relative to the Credit Agreement.

                12. Miscellaneous. Article IX of the Credit Agreement is
       incorporated herein by reference and shall apply to this Amendment.
       Execution of this Amendment shall not constitute an agreement by the
       Agent or any Bank to execute any other amendment, waiver or
       modification of the Credit Agreement. References to the Credit
       Agreement in any document relating thereto shall be deemed to include
       this Amendment. This Amendment may be executed in counterparts.

                13. Effectiveness. This Amendment and Waiver shall be
       effective when (a) the Agent has received a Ten Thousand Dollar
       ($10,000) amendment fee and (b) the parties have each received a fully
       executed copy of this Amendment and Waiver.

                14. Excluded Charges. For the purposes of determining compliance
       with the covenants set forth in Sections 6.25 and 6.26 (as renumbered
       above) of the Agreement (but not for the purposes of the definition of
       "Applicable Margin") for the fiscal quarters ending on December 31, 2000,
       March 31, 2001, June 30, 2001 and September 30, 2001 (but not
       thereafter), EBITDA shall be calculated without taking into account an
       aggregate of One Million Dollars ($1,000,000) (but no more) of charges
       recorded in the fiscal quarter ended December 31, 2000.

IN WITNESS WHEREOF, Borrowers, the Agent and the Banks have caused this
Amendment to be duly executed and delivered as of the date and year first above
written.


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                                    MARLTON TECHNOLOGIES, INC.

                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg
                                        Title: Chief Executive Officer


                                    SPARKS EXHIBITS HOLDING CORPORATION

                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg


                                    SPARKS EXHIBITS & ENVIRONMENTS CORP.

                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg


                                    SPARKS EXHIBITS & ENVIRONMENTS, LTD.

                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg


                                    SPARKS EXHIBITS & ENVIRONMENTS, INC.

                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg


                                    SPARKS EXHIBITS & ENVIRONMENTS, INCORPORATED

                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg


                                    SPARKS SCENIC LTD.

                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg


                                    SPARKS PRODUCTIONS LTD.

                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg

                                    DMS STORE FIXTURES LLC


                                    By: /s/ Robert B. Ginsburg
                                        ----------------------------------------
                                        Name: Robert B. Ginsburg



                                    FIRST UNION NATIONAL BANK, as Bank and as
                                    Agent

                                    By: /s/ Julie Reed
                                       -----------------------------------------
                                       Name:  Julie Reed
                                       Title: Senior Vice President


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