EXHIBIT 4.6

                                                                  EXECUTION COPY

               SHARED TECHNOLOGIES FAIRCHILD COMMUNICATIONS CORP.,
                                     Company

                       SHARED TECHNOLOGIES FAIRCHILD, INC.
                              VARIOUS SUBSIDIARIES
                     FINANCIAL PLACE COMMUNICATIONS COMPANY
                                 VSI CORPORATION
                                   Guarantors


               12-1/4% Senior Subordinated Discount Notes Due 2006



                          First Supplemental Indenture
                           Dated as of March 13, 1996

                                       to

                       Indenture Dated as of March 1, 1996





                    UNITED STATES TRUST COMPANY OF NEW YORK,
                                     Trustee





     FIRST SUPPLEMENTAL INDENTURE dated as of March 13, 1996 by and among SHARED
TECHNOLOGIES  FAIRCHILD   COMMUNICATIONS  CORP.,  a  Delaware  corporation  (the
"Company"), SHARED TECHNOLOGIES FAIRCHILD INC., a Delaware corporation ("STFI"),
various  subsidiaries  of the Company  listed on the signature  page hereto (the
"Subsidiary Guarantors" and, with STFI, the "STFC Guarantors"), VSI CORPORATION,
a Delaware  Corporation  ("VSI"),  FINANCIAL PLACE  COMMUNICATIONS  COMPANY,  an
Illinois  general  partnership  ("FPCC") and UNITED  STATES  TRUST  COMPANY (the
"Trustee").  Capitalized terms used herein but not defined herein shall have the
meaning ascribed thereto in the Indenture.


     WHEREAS,  the  Company,  the  Subsidiary  Guarantors,  STFI and the Trustee
entered into an Indenture (the "Original  Indenture")  dated as of March 1, 1996
for the benefit of the other  parties  and for the equal and ratable  benefit of
the Holders of the Company's 12-1/4% Senior Subordinated Discount Notes Due 2006
(the "Initial Notes") and, if and when issued pursuant to a registered  exchange
for Initial Notes, the Company's 12-1/4% Senior Subordinated  Discount Notes Due
2006 (the  "Exchange  Notes")  and,  if and when  issued  pursuant  to a private
exchange for Initial Notes, the Company's 12-1/4% Senior  Subordinated  Discount
Notes Due 2006 (the  "Private  Exchange  Notes" and,  together with the Exchange
Notes  and  the  Initial  Notes,  the  "Notes").   The  Original   Indenture  as
supplemented by this First Supplemental  Indenture is hereinafter referred to as
the "Indenture".

     WHEREAS,  Section 9.01 of the Original Indenture provides that the Company,
the STFC  Guarantors  and the Trustee may amend the Original  Indenture  without
notice to or  consent of any  Noteholder  (as  defined  in  Section  1.01 of the
Indenture).

     WHEREAS,  VSI, FPCC, the Company,  STFI and the Subsidiary  Guarantors have
agreed that VSI will become a Subsidiary  Guarantor and FPCC will become an STFC
Guarantor under the Indenture.

     WHEREAS,  all things necessary to make this First Supplemental  Indenture a
valid indenture supplemental to the Original Indenture have been done.

     NOW,  THEREFORE,  in  consideration  of the premises and mutual  agreements
contained herein and for other good and valuable  consideration,  the receipt of
which are hereby acknowledged, the parties hereto agree as follows:



                                    ARTICLE I

     SECTION 1.1  Agreement  to be  Bound.  VSI  hereby  agrees to be bound as a
Subsidiary Guarantor,  and FPCC agrees to be bound as an STFC Guarantor,  by the
terms and provisions of the Original Indenture, including without limitation the
terms and provisions contained in Article 11 thereof.

     SECTION 1.2 STFC  Guarantors.  VSI shall for all  purposes be a  Subsidiary
Guarantor  under the Indenture and shall  exercise  every right and power of the
other  Subsidiary  Guarantors  with the same effect as if it had been named as a
Subsidiary  Guarantor  under  the  Original  Indenture  and FPCC  shall  for all
purposed be an STFC Guarantor under the Indenture and shall exercise every right
and power of the other STFC  Guarantors  with the same  effect as if it had been
named as an STFC Guarantor under the Original Indenture.  Except as specifically
modified herein, the Original Indenture is in all respect ratified and confirmed
and shall remain in full force and effect in accordance with its terms.

     SECTION 1.3  Execution of Supplemental  Indenture.  This First Supplemental
Indenture is executed and shall be construed as an indenture supplemental to the
Original  Indenture  and,  as  provided in the  Original  Indenture,  this First
Supplemental  Indenture  forms  a  part  thereof.  The  Original  Indenture,  as
supplemented  and  amended  by  this  First  Supplemental  Indenture,  is in all
respects  hereby  adopted,  ratified and confirmed.  Except as herein  expressly
otherwise defined,  the use of the terms and expressions herein is in accordance
with the definitions, uses and constructions contained in the Indenture.


                                   ARTICLE II

                                  Miscellaneous

     SECTION 2.1 Governing Law. This First Supplemental  Indenture and the Notes
shall be governed by, and construed in accordance with, the laws of the State of
New York but without giving effect to applicable  principles of conflicts of law
to the extent that the application of the laws of another  jurisdiction would be
required thereby.

     SECTION 2.2  Successors.  All  agreements  of  the  Company  and  the  STFC
Guarantors  in the  Indenture  and the Notes and  Guaranties  shall  bind  their
respective successors. All agreements of the Trustee in the Indenture shall bind
its successors.

     SECTION 2.3  Multiple Originals.  The parties may sign any number of copies
of this First Supplemental Indenture. Each signed copy shall be an original, but
all of 

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them together  represent the same agreement.  One signed copy is enough to prove
this First Supplemental Indenture.

     SECTION 2.4   Table  of   Contents;   Headings.   The  table  of  contents,
cross-reference  sheet and  headings of the  Articles and Sections of this First
Supplemental Indenture have been inserted for convenience of reference only, are
not intended to be considered a part hereof and shall not modify or restrict any
of the terms or provisions hereof.

     SECTION 2.5. Responsibility for Recitals, etc. The recitals herein shall be
taken as the statements of VSI, the Company, STFI and the Subsidiary Guarantors,
and the Trustee  assumes no  responsibility  for the  correctness  thereof.  The
Trustee makes no representations as to the validity or sufficiency of this First
Supplemental Indenture.

     IN WITNESS WHEREOF,  the parties hereto have caused this First Supplemental
Indenture to be duly executed, all as of the date first written above.



                                          SHARED TECHNOLOGIES FAIRCHILD 
                                          COMMUNICATIONSECORP.,

                                          by: /s/ Vincent DiVincenzo
                                             ------------------------
                                             Name:  Vincent DiVincenzo
                                             Title:  Treasurer


                                          SHARED TECHNOLOGIES FAIRCHILD INC.,
                                          as Guarantor,

                                          by: /s/ Vincent DiVincenzo
                                             ------------------------
                                             Name:  Vincent DiVincenzo
                                             Title:  Treasurer


                                          MULTI-TENANT SERVICES, INC.,
                                          as Guarantor,

                                          by: /s/ Vincent DiVincenzo
                                             ------------------------
                                             Name:  Vincent DiVincenzo
                                             Title:  Treasurer


                                          VSI CORPORATION,
                                          as Guarantor,

                                          by: /s/ Vincent DiVincenzo
                                             ------------------------
                                             Name:  Vincent DiVincenzo
                                             Title:  Treasurer

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                                          BOSTON TELECOMMUNICATIONS
                                          GROUP, INC.,
                                          as Guarantor,

                                          by: /s/ Vincent DiVincenzo
                                             ------------------------
                                             Name:  Vincent DiVincenzo
                                             Title:  Treasurer


                                          OFFICE TELEPHONE MANAGEMENT,
                                          as Guarantor,

                                          by: /s/ Vincent DiVincenzo
                                             ------------------------
                                             Name:  Vincent DiVincenzo
                                             Title:  Treasurer


                                          STI INTERNATIONAL, INC.,
                                          as Guarantor,

                                          by: /s/ Vincent DiVincenzo
                                             ------------------------
                                             Name:  Vincent DiVincenzo
                                             Title:  Treasurer


                                          FINANCIAL PLACE COMMUNICATIONS
                                          COMPANY,
                                          as Guarantor,

                                          by SHARED TECHNOLOGIES
                                             FAIRCHILD INC.,
                                             General Partner,

                                          by: /s/ Vincent DiVincenzo
                                             ------------------------
                                             Name:  Vincent DiVincenzo
                                             Title:  Treasurer


                                          UNITED STATES TRUST COMPANY OF 
                                          NEW YORK,

                                          by: /s/ Gerard V. Ganey
                                             ------------------------
                                             Name: Gerard V. Ganey
                                             Title: Senior Vice President

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