Exhibit 10.3

                                THIRD AMENDMENT TO 
                            LOAN AND SECURITY AGREEMENT

        THIS THIRD AMENDMENT TO LOAN AND SECURITY AGREEMENT this "First 
Amendment") is dated as of May 31, 1997 and is entered into between 
SCIENTIFIC TECHNOLOGIES INCORPORATED, an Oregon corporation doing business 
in California as Oregon Scientific Technologies (the "Borrower"), and BANK 
OF THE WEST, a California banking corporation (the "Bank").

RECITALS:

        A.      Borrower and Bank have entered into that certain Loan and 
Security Agreement dated November 29, 1994 as amended by that certain First 
Amendment to the Loan and Security Agreement dated as of May 31, 1995 and 
that certain Second Amendment to the Loan and Security Agreement dated as 
of May 31, 1996 (collectively, the "Loan Agreement") and that certain 
Equipment Purchase Line Note dated December 6, 1994 (the "Equipment 
Purchase Line Note");

        B.      Borrower and Bank intend to further amend the Loan Agreement as 
provided by this First Amendment.

AMENDMENT:

        NOW, THEREFORE, Borrower and Bank hereby agree as follows:

        1.      This Third Amendment shall modify and, to the extent 
inconsistent with, amend the Loan Agreement and/or the Equipment Purchase 
line Note.  Any capitalized term not specifically defined herein shall have 
the meaning ascribed to it in the Loan Agreement.

        2.      The last sentence of Section 3.1(a) of the Loan Agreement is 
hereby deleted in its entirety and is replaced with the following:

For the purpose of this Agreement, "Draw Period" shall mean the 
period between the date of this Loan and Security Agreement and the 
earlier of: (i) May 31, 1998 or (ii) the date on which the aggregate 
of all advances made pursuant to this Section 3.1 equals Five Hundred 
Thousand and 00/100 Dollars ($500,000.00).

        3.      The last sentence of Section 3.3(b) of the Loan Agreement is 
hereby deleted in its entirety and is replaced with the following:

        For the purpose of this Agreement, the "Interim Maturity Date" shall 
mean May 31, 1998.

        4.      The last sentence of Section 3.3(c) of the Loan Agreement is 
hereby deleted in its entirety and is replaced with the following:

        For the purpose of this Agreement, the "Term Maturity Date" shall 
mean May 31, 1998.

        5.      The second sentence of the first paragraph of Section 4.1 of 
the Loan Agreement is hereby deleted in its entirety and is replaced with 
the following:

Borrower's right to obtain advances under Section 2.1 and to enter 
into foreign exchange contracts under the FX Facility provided by 
Section 14.1 shall remain in full force and effect until May 31, 
1998, and shall continue on a month-to-month basis thereafter until 
terminated by either party on thirty (30) days prior written notice 
to the other.

        6.      The last sentence of the fourth paragraph of the Equipment 
Purchase Line Note is hereby deleted in its entirety and is replaced with 
the following:

        For the purpose of this Note, the "Interim Maturity Date" shall mean 
May 31, 1998.

        7.      The last sentence of the fifth paragraph of the Equipment 
Purchase Line Note is hereby deleted in its entirety and is replaced with 
the following:

        For the purpose of this Note, the "Term Maturity Date" shall mean May 
31, 1998.

        8.      Concurrently with the execution of this Third Amendment, 
Borrower shall pay to Bank a fee in an annual amount equal to Six Thousand 
Five Hundred Dollars ($6,500.00), which fee shall represent an 
unconditional and nonrefundable payment to Bank in consideration of Bank's 
agreement to enter into this First Amendment.

        9.      Bank's duties to extend and renew the Obligations and to make 
advances in accordance with this Third Amendment shall be subject to (i) 
there being no outstanding and uncured details under the Loan Agreement, 
the Equipment Purchase Line or any other obligation owing by borrower to 
Bank and (ii) the satisfaction of each of the conditions precedent set 
forth in Article 6 of the Loan Agreement, each of which is incorporated 
herein by this reference.

        10.     Except as amended by this Third Amendment, all of the terms and 
conditions of the Loan Agreement (and each and every document or instrument 
executed and delivered in connection therewith) is and shall remain in full 
force and effect.


        11.     Except as amended by this Third Amendment, Borrower hereby 
ratifies, reaffirms, and remakes as of the date hereof each and every 
representation and warranty contained in the Loan Agreement, the Equipment 
Purchase Line Note, or in any document executed and delivered in connection 
therewith.

        IN WITNESS WHEREOF, Borrower has executed and delivered this Third 
Amendment to Bank on the date first above written at Walnut Creek, 
California.

"BORROWER"

SCIENTIFIC TECHNOLOGIES INCORPORATED,
an Oregon corporation doing business in 
California as
Oregon Scientific Technologies

By: s/l Joseph J. Lazzara               

Its: President & CEO                    

        IN WITNESS WHEREOF, Bank hereby accepts this Third Amendment to be 
effective as of the date first above written in Walnut Creek, California.

"BANK"

BANK OF THE WEST,
a California banking corporation

By: s/l R. W. Hansen                    

Its: Vice President