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                         Exhibit 4(A)

SECOND AMENDMENT  TO LOAN AND SECURITY AGREEMENT AND LIMITED
                          WAIVER
                                 
This Second Amendment to Loan and Security Agreement ("Amendment") is dated 
as of February 24, 1997, and entered into by and among HELLER FINANCIAL, 
INC., as Agent ("Agent") and Lender ("Lender"), UNITEL VIDEO, INC.  
("Borrower") and R Squared, Inc. ("Corporate Guarantor").

     WHEREAS, Agent, Lender, Borrower and Corporate Guarantor have entered 
into a Loan and Security Agreement  (as amended, the "Agreement") dated 
December 12, 1995; and
     
     WHEREAS, certain Events of Default are in existence under the Agreement 
as set forth in (i) that certain letter from Agent to Borrower dated January 
2, 1997 and (ii) that certain letter from Agent to Borrower dated January 7, 
1997 (the "Existing Events of Default") and, as a result of such Events of 
Default, Agent and Lenders have, among things, commenced charging the Default 
Rate on the Obligations; and 

     WHEREAS, Borrower and Corporate Guarantor have requested that Agent and 
Requisite Lenders waive the Existing Events of Default; and

     WHEREAS, Borrower and Corporate Guarantor have requested that Agent and 
Requisite Lenders amend the Agreement to, among other things, defer the 
principal payment due date of Term Loan B from December 31, 1996 to February 
28, 1997, and Agent and Requisite Lenders have agreed to do so, subject to 
the following terms and conditions; and

     NOW THEREFORE, in consideration of the mutual conditions and agreements 
set forth in the Agreement and this Amendment, and other good and valuable 
consideration, the receipt and sufficiency of which are hereby acknowledged, 
the parties, intending to be legally bound, hereby agree as follows:

                      ARTICLE I. DEFINITIONS
                                 
     Section 1.01.  Definitions.  Capitalized terms used in this Amendment, 
to the extent not otherwise defined herein, shall have the same meanings as 
in the Agreement, as amended hereby.  
     

                                   ARTICLE II.  AMENDMENTS 
                                 
     Section 2.01.  Amendment to Subsection 2.1(A)(2) "Term Loan B".  
Subsection 2.1(A)(2) shall be, and the same is hereby amended by deleting the 
defined term "Scheduled Installment of Term Loan B" appearing in the second 
paragraph of said subsection in its entirety and substituting the following 
therefor:

                                 


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    "Scheduled Installment of Term Loan B" means the principal
    installment in an amount equal to $4,934,410.27, payable, subject
    to the provisions of subSection 2.4(B), on or before February 28,
    1997 or the earlier to occur of (i) the Termination Date or (ii)
    the acceleration of the Obligations in accordance with the
    provisions of subsection 8.3, at which time the entire unpaid
    principal amount thereof plus accrued interest thereon shall be
    due and payable.

    Section 2.02.  Amendment to Subsection 2.1(B) "Revolving Loan". 
Subsection 2.1(B) shall be, and the same is hereby amended by deleting the 
definition of "Maximum Revolving Loan Amount" appearing in paragraph (1) in 
its entirety and substituting the following therefor:

    "Maximum Revolving Loan Amount" means, as of any date of
    determination, the lesser of (a) the Revolving Loan Commitment
    minus (i) the Letter of Credit Reserve and (ii) the Special
    Reserve and (b) the Borrowing Base minus (i) the Letter of Credit
    Reserve and (ii) the Special Reserve.

    Section 2.03.  Amendment to Subsection 5.1(F) "Borrowing Base 
Certificates".  Subsection 5.1(F) shall be, and the same is hereby amended by 
deleting the first sentence of said subsection in its entirety and 
substituting the following therefor:

    "As early as possible each week, but in no event later than by
    12:00 (noon) (Chicago time) on the fifth Business Day of each
    Week, Borrower shall deliver to Agent a Borrowing Base
    Certificate updated to reflect the most recent sales and
    collections of Borrower and an assignment schedule of all
    Accounts created by Borrower for the prior week." 


                  ARTICLE III.  LIMITED WAIVER
                                 
    Agent and Lender hereby waive the Existing Events of Default (which 
waiver shall be deemed effective as of November 30, 1996), conditioned on the 
following: (i) that for the period between January 24, 1997 through January 
30, 1997, the outstanding principal amount of the Revolving Loan shall not 
exceed the Maximum Revolving Loan Amount by an amount greater than 
$545,781.50; (ii) for the period between January 31, 1997 through February 6, 
1997, the outstanding principal amount of the Revolving Loan shall not exceed 
the Maximum Revolving Loan Amount by an amount greater than $195,781.50; 
(iii) on and after February 7, 1997, the Maximum Revolving Loan Amount shall 
be greater than or equal to the outstanding principal amount of the Revolving 
Loan and (iv) for so long as the outstanding principal amount of the 
Revolving Loan exceeds the Maximum Revolving Loan Amount, (A) the Loans and 
all other Obligations shall bear interest at a rate equal to two percent (2%) 
plus the applicable Interest Rate and (B) Borrower may not request any LIBOR 
Rate Loans and Borrower may not convert any Base Rate Loans into LIBOR Rate 
Loans.  Borrower's compliance with the terms above, shall not be deemed to 
constitute a commitment by Agent or Lenders to provide advances under the 
Revolving Loan that exceed the Maximum Loan Amount.  This limited waiver 
shall not be 

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deemed to constitute a waiver of any other existing Events of Default or any 
future breach of the Agreement or any of the other Loan Documents (including, 
without limitation, any subsequent breach of the covenants described in the 
letters referenced above for any subsequent period). 

                                 
                    ARTICLE IV.  MISCELLANEOUS
                                 
    Section 4.01.  Conditions. The effectiveness of this Amendment is subject 
to the satisfaction of the following conditions precedent (unless 
specifically waived in writing by Agent and Requisite Lenders):
     
(a)  there shall have occurred no material adverse change in the
     business, operations, financial conditions, profits or prospects,
     or in the Collateral of the Borrower; 

(b)  Borrower and Corporate Guarantor shall have executed and
     delivered such other documents and instruments as Agent may
     require;

(c)  Borrower shall have paid to Agent, for the benefit of
     Lenders, a fee in the amount of $10,000, which fee shall have
     been fully earned upon payment. 

(d)  all corporate proceedings taken in connection with the
     transactions contemplated by this Amendment and all documents,
     instruments and other legal matters incident thereto shall be
     satisfactory to Agent and its legal counsel.

     Section 4.02  Ratification.  The terms and provisions set forth in this 
Amendment shall modify and supersede all inconsistent terms and provisions 
set forth in the Agreement and, except as expressly modified and superseded 
by this Amendment, the terms and provisions of the Agreement, are ratified 
and confirmed and shall continue in full force and effect.  

     Section 4.03  Corporate Action.  The execution, delivery and performance 
of this Amendment have been authorized by all requisite corporate action on 
the part of Borrower and Corporate Guarantor and will not violate the 
Articles of Incorporation or Bylaws of either Borrower or Corporate Guarantor.

     Section 4.04  Severability.  Any provision of this Amendment held by a 
court of competent jurisdiction to be invalid or unenforceable shall not 
impair or invalidate the remainder of this Amendment and the effect thereof 
shall be confined to the provision so held to be invalid or unenforceable.

     Section 4.05  Successors and Assigns.  This Amendment is binding upon 
and shall inure to the benefit of Agent, Lender, Borrower and Corporate 
Guarantor and their respective successors and assigns.

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     Section 4.06  Counterparts.  This Amendment may be executed in one or 
more counterparts, each of which when so executed shall be deemed to be an 
original, but all of which when taken together shall constitute one and the 
same instrument.

     IN WITNESS WHEREOF, the parties have executed this Amendment on the date 
first above written.
                         
                              HELLER FINANCIAL, INC.,
                              as Agent and Lender

                              By:  /s/ Jerome Sepich
                                 ------------------------
                              Title:    Vice President
     

                              UNITEL VIDEO, INC.,
                              as Borrower

                              By:  /s/ Barry Knepper
                                 -------------------------
                              Title:    CEO  

                              R SQUARED, INC.,
                              as Corporate Guarantor

                              By:  /s/ Barry Knepper 
                                 --------------------------
                              Title:    CEO 

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