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                                  EXHIBIT 10bb

                     AMENDMENT NO. 1 TO AMENDED AND RESTATED
                     REVOLVING CREDIT AND SECURITY AGREEMENT


         AMENDMENT NO. 1 dated as of February 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. Excluded Reserves. For purposes of determining compliance with the
 covenants set forth hi Section 6.25, 6.26 and 6.27 of the Agreement and for
 purposes of the definition of "Applicable Margin," for the fiscal quarters
 ending on September 30, 2000, December 31, 2000, March 31, 2001 and June 30,
 2001 (but not thereafter), EBITDA shall be calculated without taking into
 account an aggregate of Two Million Dollars ($2,000,000) (but no more) recorded
 as accounts receivable and inventory reserves (the "Excluded Reserves") as of
 the fiscal quarter ended September 30, 2000; provided that, to the extent there
 is a decrease in or reversal of the Excluded Reserves, the resulting income
 shall not be taken into account for the above-referenced purposes.

          2.  "Applicable Margin." The definition of "Applicable Margin" shall
be amended to read in full as follows:

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


                                                           Applicable Margin:

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

Higher than 3.00:1 (it being                                2.75%         0.50%
acknowledged that the maximum
permitted ratio of Senior Funded Debt
to EBITDA may never exceed the
amount permitted under Section 6.25)

3.00:1 or lower, but higher than 2.50:1                     2.00%         0.00%

2.50:1 or lower, but higher than 2.00:1                     1.75%        -0.25%

Less than or equal to 2.00:1                                1.25%        -0.25%

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                  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 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 3.00:1, 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.

         3. Senior Funded Debt to EBITDA Ratio. Section 6.25 shall be amended to
 read in full as follows:

                  The Borrowers will not permit the ratio of Senior Funded Debt,
                  determined as of the last day (a "Measurement Date") of each
                  period of four consecutive fiscal quarters of MTI, to EBITDA
                  for such period to be greater than (a) 3.50:1.00 for each such
                  period ending on or prior to September 30, 2001, and (b)
                  thereafter, 3.25:1.0.

         4. Representations and Covenants. The Borrowers hereby represent,
 warrant and certify that, assuming the effectiveness of Paragraph 1 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.

         5. 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.

         6. 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 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.

         7.   Effectiveness. This Amendment shall be effective when (a) the
Agent has received a Fifty Thousand Dollar ($50,000) amendment fee and (b) the
parties have each received a fully executed copy of this Amendment.


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 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.


                                            MARLTON TECHNOLOGIES, INC.

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

                                            SPARKS EXHIBITS HOLDING CORPORATION

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

                                            SPARKS EXHIBITS & ENVIRONMENTS CORP.

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

                                            SPARKS EXHIBITS & ENVIRONMENTS, LTD.

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

                                            SPARKS EXHIBITS & ENVIRONMENTS, INC.

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

                                            SPARKS EXHIBITS & ENVIRONMENTS,
                                            INCORPORATED

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

                                            SPARK SCENIC LTD.

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

                                            DMS STORE FIXTURES LLC.

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

                                            FIRST UNION NATIONAL BANK,
                                            as Bank and as Agent

                                            By: /s/ John L. Thomas
                                                --------------------------------
                                                   Vice President


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                               Update to Schedules



ss.  5.4 MTI has provided to the Bank its Form 10-K for the period ended
     December 31, 1999, and its Form 10-Qs for the fiscal quarters ended March
     31, June 30, and September 30, 2000.

ss.  5.16 GE Capital Corporation capital lease for up to $ $725,000 incurred
     pursuant to Section 6.4 of the Agreement.




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