FIRST AMENDMENT TO AMENDED AND RESTATED REVOLVING CREDIT AND SECURITY AGREEMENT

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                                                                   Exhibit 10.20

            FIRST AMENDMENT TO AMENDED AND RESTATED REVOLVING CREDIT
                             AND SECURITY AGREEMENT

THIS First Amendment to Amended and Restated Revolving Credit and Security
Agreement (this "Amendment") amends that certain Amended and Restated Revolving
Credit and Security Agreement dated as of November 28, 2006 (the "Agreement")
between TRANSACT TECHNOLOGIES INCORPORATED (the "Borrower"), and TD Banknorth
N.A., a national banking association (the "Bank") (collectively, the Agreement
and this Amendment and any further or other amendment shall be referred to as
the "Credit Agreement") is made and entered into as of the 30th day of
September, 2007 by and between the Borrower and the Bank. Capitalized terms used
herein but not defined shall have the meanings assigned to them in the Credit
Agreement.

1.    AMENDMENT TO CREDIT AGREEMENT. In consideration of mutual covenants herein
     contained and for other good and valuable consideration, the receipt and
     sufficiency of which are hereby acknowledged, the Borrower and the Bank do
     hereby amend the Credit Agreement as follows:

          a.    Section 7.1 of the Credit Agreement is amended in its entirety to
               read as follows:

          7.1 Operating Cash Flow to Total Debt Service Ratio. Borrower shall,
          maintain a ratio of Operating Cash Flow for the preceding four fiscal
          quarters plus the applicable Permitted Add Back as provided below to
          Total Debt Service at the end of each fiscal quarter of not less than
          1.25 to 1.00.

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<CAPTION>
Period Ending                                          Permitted Add Back
-------------                                           ------------------
<S>                                                    <C>
Fiscal Quarter Ending September 30, 2007               not to exceed $1,750,000
Fiscal Quarter Ending December 31, 2007                not to exceed $4,500,000
Fiscal Quarter Ending March 31, 2008                   not to exceed $4,500,000
Fiscal Quarter Ending June 30, 2008                    not to exceed $5,000,000
Fiscal Quarter Ending September 30, 2008               not to exceed $2,250,000
All Fiscal Quarters Ending after September 30, 2008    $0.00
</TABLE>

          b.    Exhibit 1 is amended by amending and restating the following in
               its entirety:

               "Operating Cash Flow" means EBITDA less cash taxes paid or
               distributions to shareholders of any nature, less unfinanced
               Capital Expenditures; provided that for the