FIFTH  AMENDMENT  AND WAIVER  dated as of  September  23, 1997 to the  Revolving
Credit Loan Agreement  dated January 31, 1995, as amended by the FIRST AMENDMENT
dated as of August 3, 1995, the SECOND AMENDMENT AND WAIVER dated as of November
10, 1995, and AMENDMENT OF REVOLVING  CREDIT LOAN  AGREEMENT  dated December 27,
1995 and the  FOURTH  AMENDMENT  AND  WAIVER  dated as of May 2, 1997 (the "Loan
Agreement") among TII INTERNATIONAL,  INC., a Delaware  corporation with offices
located at 1385 Akron  Street  Copiague,  New York 11726 (the  "Borrower"),  TII
INDUSTRIES,  INC.,  a Delaware  corporation  with  offices at 1385 Akron  Street
Copiague,  New York 11726  ("Industries") and THE CHASE MANHATTAN BANK (formerly
known as Chemical  Bank), a New York State banking  corporation  with offices at
395 North Service Road, Suite 302, Melville,  New York 11747 (the "Bank") and to
the Master Lease  Purchase  Agreement  Number 00009 dated  January 12, 1996,  as
amended by a letter dated February 1, 1996 (collectively, the "Lease Agreement")
by and between the Borrower and CHASE EQUIPMENT LEASING, INC. (formerly known as
ChemLease Worldwide, Inc.) ("Leasing"). Capitalized terms used but not otherwise
defined herein shall have the meanings set forth in the Loan Agreement.

WHEREAS,  the Lease Agreement provides that the financial covenants contained in
any credit  facility  provided  by the Bank to the  Borrower  shall apply to the
Lease Agreement as continuing covenants; and

WHEREAS,  the Borrower and  Industries  have  requested and the Bank and Leasing
have each agreed,  subject to the terms and  conditions of this FIFTH  AMENDMENT
AND WAIVER,  to amend and waive  compliance with certain  provisions of the Loan
Agreement  and the Lease  Agreement (by  incorporation)  to reflect the requests
made by the Borrower to the Bank and Leasing in the manner hereafter set forth;

NOW, THEREFORE,  in consideration of the premises and of other good and valuable
consideration,  the receipt and sufficiency of which is hereby acknowledged, the
parties hereto agree as follows:

     1.   Waiver of Article  VII.  Negative  Covenants.  Section  7.09.  Capital
          Expenditures.

          Compliance  with Section 7.09 of the Loan  Agreement is hereby  waived
          for the  fiscal  year ended June 30,  1997 to permit the  Borrower  to
          incur  consolidated  capital  expenditures  in excess  of  $3,500,000,
          provided,  however,  that  consolidated  capital  expenditures did not
          exceed $4,850,000 for the fiscal year ended June 27, 1997.

     2.   Waiver of Article VII. Negative Covenants.  Section 7.13. Tangible Net
          Worth.

          Compliance with Section 7.13 of the Loan Agreement,  as amended by the
          Amendment of Revolving  Credit Loan Agreement dated December 27, 1995,
          is hereby waived for the fiscal year ended June 27, 1997 to permit the
          Consolidated  Tangible Net Worth of Industries and its Subsidiaries to
          fall below $34,000,000,  provided, however, that Consolidated Tangible
          Net Worth did not fall below $31,700,000 for such fiscal year end.

     3.   Amendment to Article VII. Negative  Covenants.  Section 7.13. Tangible
          Net Worth.

          Section  7.13 of the Loan  Agreement,  as amended by the  Amendment of
          Revolving  Credit Loan  Agreement  dated  December 27, 1995, is hereby
          further  amended by replacing the Periods and Amounts therein with the
          following:

                   "Period                           Amount

                   6/27/97 - 6/25/98                 $31,200,000
                   6/26/98 - 6/24/99                 $33,700,000

          and for each comparable fiscal period  thereafter  commencing with the
          fiscal year ending 6/25/99 through the day before the following fiscal
          year end  date,  the sum of the  prior  year's  required  Consolidated
          Tangible Net Worth plus $2,000,000."




     4.   Waiver of Article VII. Negative Covenants.  Section 7.16. Consolidated
          Net Loss.

          Compliance with Section 7.16 of the Loan Agreement is hereby waived to
          permit the  Borrower to incur a  Consolidated  Net Loss for the Fiscal
          Quarters  ended March 28, 1997 and June 27, 1997,  provided,  however,
          that such  losses  did not  exceed  $2,326,000  and  $200,000  for the
          respective fiscal periods.

     5.   Waiver of Article VII. Negative Covenants.  Section 7.17. Debt Service
          Ratio.

          Compliance  with Section 7.17 of the Loan  Agreement is hereby  waived
          for the Fiscal  Quarter ended June 27, 1997 to permit the Debt Service
          Ratio to be less than 1.35 to 1.0, provided,  however, that such ratio
          did not fall below 0.05 to 1.0 for such period.

     6.   Waiver of Article VI. Affirmative  Covenants.  Section 6.01. Corporate
          Existence, Solvency, Properties, Etc.

          Compliance with Section 6.01 of the Loan Agreement is hereby waived to
          permit TII-Ditel, Inc. (formerly known as Ditel, Inc.) to be insolvent
          as of the Fiscal Year ended June 30, 1997.

          Compliance  with Section 6.01 of the Loan  Agreement is hereby further
          waived to permit the  dissolution  of TII  Industries NC, Inc. and TII
          Electronics, Inc.

     7.   Amendment  to  Article  VI.  Affirmative   Covenants.   Section  6.01.
          Corporate Existence, Solvency, Properties, Etc.

          Section 6.01 of the Loan  Agreement is hereby  amended by deleting the
          phrase "and further  provided that Ditel,  Inc. may be insolvent  from
          the Closing  Date through  January 31, 1996,  at which time it must be
          solvent and  continue to be solvent"  and  substituting  therefor  the
          following:

               "and further provided that TII-Ditel,  Inc. may be insolvent from
               the Closing Date  through July 1, 1998,  at which time it must be
               solvent and continue to be solvent."

     8.   Amendment to Article VI. Affirmative Covenants.

          Article VI of the Loan  Agreement is hereby amended by the addition of
          the following Section:

          "Section  6.15. TII-Ditel, Inc.   Not later than 60 days from the date
          hereof,  Industries  shall  provide  the Bank with all of the  capital
          stock of TII-Ditel, Inc. owned by Industries,  (which shall constitute
          not less than 99.6% of the  outstanding  capital  stock of  TII-Ditel,
          Inc.),  together with executed but undated stock powers,  stock pledge
          agreement,  legal opinion,  and such other corporate  documentation as
          shall be required by the Bank."

     9.   Waiver of Article VII. Negative Covenants. Section 7.01. Indebtedness.

          Compliance with Section 7.01 of the Loan Agreement is hereby waived to
          permit the  Borrower  to enter into a certain  Master  Lease  Purchase
          Agreement  dated  January 12, 1996 by and  between  the  Borrower  and
          ChemLease  Worldwide,  Inc.  (now  known as Chase  Equipment  Leasing,
          Inc.).

     10.  Other Waivers - Loan Agreement.

          (a) Compliance  with the Loan Agreement is hereby waived to permit the
          restatement of Industries' charter documents prior to the date hereof;
          and

          (b) Compliance  with the Loan Agreement is hereby waived to permit the
          change of name of the  corporation  formerly  known as Ditel,  Inc. to
          TII-Ditel, Inc.






     11.  Waiver of Article VI. Affirmative Covenants. Section 6.11. Notices.

          Compliance with Section 6.11 of the Loan Agreement is hereby waived to
          permit  the  Borrower's  failure  to  promptly  notify the Bank of the
          occurrence of the breaches, defaults or Events of Default described in
          paragraphs 1 through 6 above.

     12.  Waivers - Lease Agreement.

          The  Bank's  waivers  of  compliance  with  the  financial   covenants
          described  above granted in this FIFTH AMENDMENT AND WAIVER are hereby
          granted by Leasing with respect to the Borrower's  compliance with the
          terms and provisions of the Lease Agreement.

This FIFTH  AMENDMENT  AND WAIVER shall be construed  and enforced in accordance
with the laws of the State of New York.

Except as expressly  amended or waived hereby,  the Loan Agreement and the Lease
Agreement  shall remain in full force and effect in accordance with the original
terms  thereof.  This FIFTH  AMENDMENT  AND WAIVER  herein  contained is limited
specifically to the matters set forth above and does not constitute  directly or
by  implication  a  waiver  or  amendment  of any  other  provision  of the Loan
Agreement  or the Lease  Agreement  or any  breach,  default or Event of Default
which  may occur or may have  occurred  under  the Loan  Agreement  or the Lease
Agreement.

The Company and  Industries  hereby  represent  and warrant  that,  after giving
effect to this FIFTH AMENDMENT AND WAIVER, no Event of Default or default exists
under the Loan Agreement, the Lease Agreement or any other related documents.

This FIFTH  AMENDMENT AND WAIVER may be executed in any number of  counterparts,
each of  which  shall  constitute  an  original  but all of  which,  when  taken
together,  shall  constitute  but one FIFTH  AMENDMENT  AND  WAIVER.  This FIFTH
AMENDMENT  AND WAIVER shall become  effective  when duly  executed  counterparts
hereof which,  when taken  together,  bear the signatures of each of the parties
hereto shall have been delivered to the Bank and Leasing.

IN WITNESS WHEREOF, the Borrower,  Industries,  the Bank and Leasing have caused
this FIFTH  AMENDMENT  AND WAIVER to be duly  executed by their duly  authorized
officers all as of the day and year first above written.

TII INTERNATIONAL, INC.                       TII INDUSTRIES, INC.


By: /s/ Paul Sebetic                          By: /s/ Paul Sebetic
   --------------------------                    --------------------------
      Name: Paul Sebetic                             Name: Paul Sebetic
      Title: Vice President                          Title: Vice President



THE CHASE MANHATTAN BANK                      CHASE EQUIPMENT LEASING, INC.


By: /s/ Christopher Zimmerman                 By:
   --------------------------                    --------------------------
      Name: Christopher Zimmerman                    Name:
      Title: Vice President                          Title: 







                                     CONSENT

The  undersigned,  as Guarantors of the obligations of TII  International,  Inc.
hereby consent to the execution and delivery by TII International,  Inc. and TII
Industries, Inc. of this FIFTH AMENDMENT AND WAIVER and hereby confirm that they
remain  fully  bound by the terms of the Joint and  Several  Guaranty of Payment
dated January 31, 1995 to which they are a party.

TII INDUSTRIES, INC.                          TII CORPORATION


By: /s/ Paul Sebetic                          By: /s/ Paul Sebetic
   --------------------------                    --------------------------
      Name: Paul Sebetic                             Name: Paul Sebetic
      Title: Vice President                          Title: Vice President


TII-DITEL, INC.                               TELECOMMUNICATIONS
                                              INDUSTRIES, INC.


By: /s/ Paul Sebetic                          By: /s/ Paul Sebetic
   --------------------------                    --------------------------
      Name: Paul Sebetic                             Name: Paul Sebetic
      Title: Vice President                          Title: Vice President

                                              TII DOMINICANA, INC.


                                              By: /s/ Paul Sebetic
                                                 --------------------------
                                                     Name: Paul Sebetic
                                                     Title: Vice President