Wegener Corporation    Exhibit 4.5

                                                                  August 4, 1998

Wegener Communications, Inc.
11350 Technology Circle
Duluth, Georgia  30155

     RE:  FIRST AMENDMENT

Gentlemen:

     WEGENER  COMMUNICATIONS,  INC.,  a  Georgia  corporation  ("Borrower")  and
LaSalle National Bank, a national banking association ("Bank") have entered into
that  certain  Loan and  Security  Agreement  dated June 5, 1996 (the  "Security
Agreement").  From time to time thereafter,  Borrower and Bank may have executed
various  amendments (each an "Amendment" and  collectively the  "Amendments") to
the Security  Agreement (the Security  Agreement and the Amendments  hereinafter
are referred to, collectively, as the "Agreement"). Borrower and Bank now desire
to further  amend the  Agreement  as provided  herein,  subject to the terms and
conditions hereinafter set forth.

     NOW,  THEREFORE,  in  consideration of the foregoing  recitals,  the mutual
covenants  and   agreements  set  forth  herein  and  other  good  and  valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto hereby agree as follows:

     1.   The Agreement hereby is amended as follows:

     (a)  Paragraph (1) of Exhibit A of the Agreement is deleted in its entirety
and the following is substituted in its place:

          (1)  LOAN LIMITS: Bank may, in its sole discretion,  advance an amount
               up to the sum of the following sublimits (the "Loan Limit"):

               (a)  Subject  to  subparagraph  (4)(a) of this  Exhibit  A, up to
                    eighty  percent  (80%)  of the  face  amount  (less  maximum
                    discounts,  credits and allowances  which may be taken by or
                    granted  to  Account  Debtors in  connection  therewith)  of
                    Borrower's Eligible Accounts; plus

               (b)  Subject  to  subparagraph  (4)(b) of this  Exhibit  A, up to
                    eighty  percent  (80%)  of the  face  amount  (less  maximum
                    discounts,  credits and allowances  which may be taken

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Wegener Communications, Inc.                                 Wegener Corporation
August 4, 1998                                                       Exhibit 4.5
Page 2

                    by or granted to Account Debtors in connection therewith) of
                    Borrower's  Eligible  Accounts or Five Hundred  Thousand and
                    No/100 Dollars ($500,000.00), whichever is less; plus

               (c)  Subject  to  subparagraph  (5)(a) of this  Exhibit  A, up to
                    twenty  percent  (20%) of the  lower  of the cost or  market
                    value of Borrower's Eligible Inventory; plus

               (d)  Subject  to  subparagraph  (5)(b) of this  Exhibit  A, up to
                    twenty  percent  (20%) of the  lower  of the cost or  market
                    value of Borrower's Eligible Inventory; plus

               (e)  Subject  to  subparagraph  (5)(c) of this  Exhibit  A, up to
                    forty percent (40%) of the lower of the cost or market value
                    of Borrower's Eligible Inventory; plus

               (f)  Subject  to  subparagraph  (5)(d) of this  Exhibit  A, up to
                    fifty percent (50%) of the lower of the cost or market value
                    of Borrower's Eligible Inventory; plus

               (g)  Subject  to  subparagraph  (2)(a) of this  Exhibit  A, up to
                    eighty  percent (80%) of the purchase price of the Equipment
                    purchased  with such  advances  (exclusive  of sales  taxes,
                    delivery  charges  and other  "soft"  costs  related to such
                    purchases),  to be used  by  Borrower  from  time to time to
                    purchase new  Equipment,  or One Million and No/100  Dollars
                    ($1,000,000.00),  whichever is less; provided, that prior to
                    any advance under this subparagraph,  Borrower shall furnish
                    to Bank an invoice and  acceptance  letter for the Equipment
                    being  purchased and shall have executed such  documents and
                    taken  such other  actions  as Bank shall  require to assure
                    that Bank has a first  perfected  security  interest in such
                    Equipment;  and further  provided,  that each advance  under
                    this subparagraph shall equal or exceed One Hundred Thousand
                    and No/100  Dollars  ($100,000.00)  and may be made not more
                    frequently than quarterly; plus

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Wegener Communications, Inc.                                 Wegener Corporation
August 4, 1998                                                       Exhibit 4.5
Page 3

               (h)  Subject  to  subparagraph  (2)(b) of this  Exhibit  A, up to
                    seventy   percent   (70%)  of  the  fair  market  value  (as
                    determined  by an  appraiser  acceptable  to  Bank)  of that
                    certain real property  described in subparagraph  (14)(a) of
                    this  Exhibit A or One Million  Five  Hundred  Thousand  and
                    No/100 Dollars ($1,500,000.00), whichever is less; minus

               (i)  Such  reserve as Bank  elects,  in its sole  discretion,  to
                    establish from time to time;

                    provided,  that the aggregate  amount of Loans made pursuant
                    to subparagraphs  (1)(c),  (1)(d), (1)(e) and (1)(f) of this
                    Exhibit A shall in no event  exceed Two  Million  and No/100
                    Dollars ($2,000,000.00);

                    further  provided,  that the aggregate  amount of Loans made
                    pursuant to subparagraphs (1)(a),  (1)(b),  (1)(c),  (1)(d),
                    (1)(e),  (1)(f)  and  (1)(g)  of this  Exhibit A shall in no
                    event exceed Eight Million Five Hundred  Thousand and No/100
                    Dollars ($8,500,000.00); and

                    further provided,  that the aggregate Loan Limit shall in no
                    event    exceed   TEN    MILLION    AND    NO/100    DOLLARS
                    ($10,000,000.00),  except as such amount may be increased or
                    decreased  by Bank,  in its sole  discretion,  from  time to
                    time.

     (b)  Paragraph  (2) of  Exhibit A of the  Agreement  is  amended to add the
following provision:

          (b)  The availability described in subparagraph (1)(h) of this Exhibit
               A shall be curtailed monthly by an amount sufficient  (assuming a
               like curtailment each month) to reduce said  availability to zero
               at the end of  thirty-five  (35)  months.  Each such  curtailment
               shall  automatically  occur on the thirtieth (30th) day following
               the  date  of  disbursement  under  subparagraph  (1)(h)  of this
               Exhibit A and on the  corresponding  day of each month thereafter
               until  the  earliest  to  occur  of (i) the  date on  which  said
               availability  shall be reduced in full;  (ii) the date upon which
               demand  for

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Wegener Communications, Inc.                                 Wegener Corporation
August 4, 1998                                                       Exhibit 4.5
Page 4

               repayment  is made by Bank;  and (iii) the date upon  which  this
               Agreement terminates pursuant to the provisions of Paragraph 9 of
               the Agreement.

     (c)  Paragraph (6) of Exhibit A of the Agreement is deleted in its entirety
and the following is substituted in its place:

          (6)  INTEREST  RATE:  (I) All Loans  made  pursuant  to  subparagraphs
               (1)(a),  (1)(b),  (1)(c),  (1)(d),  (1)(e), (1)(f), and (1)(g) of
               this Exhibit A shall bear interest at Bank's  publicly  announced
               prime rate  (which is not  intended  to be Bank's  lowest or most
               favorable  rate in  effect  at any time)  (the  "Prime  Rate") in
               effect from time to time.  Interest  shall be payable on the last
               business day of each month, in arrears. Each rate of interest set
               forth herein  shall  increase or decrease  with each  increase of
               decrease in the Prime Rate,  effective on the  effective  date of
               each such change in the Prime  Rate.  Upon the  occurrence  of an
               Event of Default  and the  continuance  thereof,  each Loan shall
               bear interest at the rate of two percent (2%) per annum in excess
               of the interest rate otherwise  payable  thereon,  which interest
               shall be payable on demand;  and (II) all Loans made  pursuant to
               subparagraph  (1)(h) of this Exhibit A shall bear interest at the
               fixed  rate of 250 basis  points  per annum in excess of the five
               (5) year Treasury Rate in effect at the time of  disbursement  of
               the  Loans  under  subparagraph  (1)(h)  of this  Exhibit  A. All
               interest shall be calculated upon the basis of a 360-day year.

     (d)  Paragraph (7) of Exhibit A of the Agreement is deleted in its entirety
and the following is substituted in its place:

          (7)  FEES AND CHARGES:

               (a)  FACILITIES FEES: With respect to the first Five Million Five
                    Hundred Thousand and No/100 Dollars ($5,500,000.00) of loans
                    and advances made pursuant to subparagraphs (1)(a),  (1)(b),
                    (1)(c),  (1)(d),  (1)(e), (1)(f), and (1)(g) of this Exhibit
                    A, Borrower shall pay to Bank an annual facilities fee equal
                    to one percent (1%) of Five  Million  Five Hundred  Thousand
                    and No/100 Dollars ($5,500,000.00), payable and earned as of

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Wegener Communications, Inc.                                 Wegener Corporation
August 4, 1998                                                       Exhibit 4.5
Page 5

                    June 21,  1998 and on the same date of each year  thereafter
                    during the Original  Term and any Renewal Term. At such time
                    as the loans and  advances  made  pursuant to  subparagraphs
                    (1)(a),  (1)(b),  (1)(c), (1)(d), (1)(e), (1)(f), and (1)(g)
                    of Exhibit A exceed Five Million  Five Hundred  Thousand and
                    No/100 Dollars  ($5,500,000.00),  Borrower shall pay to Bank
                    and Bank shall  fully earn at the time of such  payment,  an
                    annual  facilities fee equal to three-fourths of one percent
                    (3/4ths  of  1%)  of  Three   Million  and  No/100   Dollars
                    ($3,000,000.00),  or a pro-rata amount thereof if paid after
                    June 21 of any  year  but  before  June 21 of the  following
                    year. Thereafter, Borrower shall pay to Bank, and Bank shall
                    fully  earn a fee  equal  to  three-fourths  of one  percent
                    (3/4ths  of  1%)  of  Three   Million  and  No/100   Dollars
                    ($3,000,000.00)  on  June  21st  of  each  year  during  the
                    Original  Term  and  any  Renewal  Term.   For  purposes  of
                    determining  whether  Borrower  has  received  any  advances
                    against the availability set forth in subparagraph (1)(h) of
                    this Exhibit A,  advances to Borrower  shall first be deemed
                    to  be  advanced  against  the  availability  set  forth  in
                    subparagraphs  (1)(h)  of this  Exhibit  A  (subject  to any
                    sublimits  contained  in  Paragraph  (1) of this  Exhibit A)
                    until the amount so advanced equals the  availability  under
                    that  paragraph,   and  then  to  the   availability   under
                    subparagraphs (1)(a), (1)(b), (1)(c), (1)(d), (1)(e), (1)(f)
                    and  (1)(g) of this  Exhibit  A  (subject  to any  sublimits
                    contained in Paragraph (1) of this Exhibit A).

               (b)  REAL ESTATE  CLOSING FEE:  Borrower shall pay to Bank a real
                    estate  closing fee equal to Seven Thousand Five Hundred and
                    No/100 Dollars ($7,500.00),  which fee shall be fully earned
                    by Bank and payable on the date of this Amendment.

     (e)  Paragraph  (7) of  Exhibit A of the  Agreement  is  amended to add the
following provision:

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Wegener Communications, Inc.                                 Wegener Corporation
August 4, 1998                                                       Exhibit 4.5
Page 6

          (7).(1)   ORIGINAL  TERM:  The date of the Original  Term set forth in
                    Paragraph 9 of the Agreement is deleted and the date of June
                    21, 2000 is substituted in its place.

     (f)  Paragraph  (11) of  Exhibit A of the  Agreement  is amended to add the
following provision:

          (11).(1)  YEAR 2000:  Borrower and its Subsidiaries  have reviewed the
                    areas within their  business and  operations  which could be
                    adversely  affected by, and have developed or are developing
                    a program  to  address  on a timely  basis,  the "Year  2000
                    Problem" (that is, the risk that computer  applications used
                    by Borrower and its  Subsidiaries may be unable to recognize
                    and  perform  properly  date-sensitive  functions  involving
                    certain dates prior to and any date on or after December 31,
                    1999), and have made related appropriate inquiry of material
                    suppliers  and  vendors.  Based on such review and  program,
                    Borrower believes that the "Year 2000 Problem" will not have
                    a  material  adverse  effect  on  its  business,  assets  or
                    condition, financial or otherwise. From time to time, at the
                    request of Bank, Borrower and its Subsidiaries shall provide
                    to Bank such  updated  information  or  documentation  as is
                    requested  regarding  the status of their efforts to address
                    the "Year 2000 Problem."

     2. This Amendment  shall not become  effective  until fully executed by all
parties hereto.

     3.  Except  as  expressly  amended  hereby  and by any  other  supplemental
documents or instruments  executed by either party hereto in order to effectuate
the transactions contemplated hereby, the Agreement and Exhibit A thereto hereby
are  ratified and  confirmed by the parties  hereto and remain in full force and
effect in accordance with the terms thereof.

                                        LASALLE NATIONAL BANK,
                                        A NATIONAL BANKING ASSOCIATION

                                        By: /s/ Philip F. Banka
                                           ---------------------
                                        Title: Vice President
                                               -----------------

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Wegener Communications, Inc.                                 Wegener Corporation
August 4, 1998                                                       Exhibit 4.5
Page 7

Accepted and agreed to this 26th day of August, 1998.

WEGENER COMMUNICATIONS, INC.

By: /s/ Robert A. Placek
    -------------------------
Title: Chairman and CEO
       ----------------------


Consented  and  agreed  to by the  following  guarantor  of the
obligations   of  WEGENER   COMMUNICATIONS,   INC.  to  LaSalle
National Bank.

WEGENER CORPORATION

By: /s/ Robert A. Placek
    -------------------------
Title: Chairman and CEO
       ----------------------

Date: August 26, 1998