<PAGE>

                                                                   Exhibit 10.30


                               FIRST AMENDMENT TO
                              EMPLOYMENT AGREEMENT

THIS FIRST AMENDMENT TO EMPLOYMENT AGREEMENT (this "Amendment"), dated this
11th day of June, 2001, is made and entered into by and between Packard
BioScience Company, a Delaware corporation (the "Company"), and Emery G. Olcott
(the "Executive").

WHEREAS, the Company and the Executive entered into an employment agreement,
dated March 4, 1997 (the "Employment Agreement"); and

WHEREAS, the Company and Executive desire to amend the Employment Agreement to
extend the term of the Employment Agreement as set forth herein.

NOW, THEREFORE, in consideration of the mutual promises contained herein, and
for other good and valuable consideration the receipt and sufficiency of which
are hereby acknowledged, the Company and Executive hereby amend the Employment
Agreement as follows:

1.    Section 1 of the Employment Agreement is hereby deleted in its entirety
      and is hereby replaced with the following:

            1. EMPLOYMENT PERIOD. The Company shall employ the Employee, and the
            Employee shall serve the Company, on the terms and conditions set
            forth in this Agreement for the period commencing on the date
            hereof, and ending on the second anniversary hereof (the "Employment
            Period"); provided, however, that commencing on the date one year
            after the date of this Employment Agreement (the "Initial Renewal
            Date"), and on the first day of each calendar month thereafter (each
            such date and the Initial Renewal Date shall be hereinafter referred
            to as a "Renewal Date"), unless previously terminated, the
            Employment Period shall be automatically extended so as to terminate
            twenty-five (25) calendar months after such Renewal Date, unless at
            least sixty days prior to the Renewal Date the Company shall give
            notice to the Executive that the Employment Period shall not be so
            extended."

2.    The EXHIBIT A attached hereto is hereby added to the Employment
      Agreement as EXHIBIT A thereto.

3.    Section 8(c)(ii) of the Employment Agreement is hereby deleted in its
      entirety and replaced with the following:
<PAGE>


            "(ii) "Competitive Activity" means any competitor identified on
            EXHIBIT A."

4.    Except as specifically amended hereby, the Employment Agreement shall
      remain in full force and effect.

5.    The Company and the Executive acknowledge that this Agreement supersedes
      any other agreement between them with respect to the subject matter
      hereof, and that this Amendment shall be incorporated into and shall form
      an integral part of the Employment Agreement.

6.    This Amendment may be executed in several counterparts, each of which
      shall be deemed an original, and said counterparts shall constitute but
      one and the same instrument.

IN WITNESS WHEREOF, the Executive has executed this Amendment and, pursuant to
the authorization of its Board of Directors, the Company has caused this
Amendment to be executed on its behalf, all as of the date first above written.


EXECUTIVE

/s/ Emery G. Olcott
---------------------------------
Emery G. Olcott


PACKARD BIOSCIENCE COMPANY


/s/ Ben D. Kaplan
----------------------------------
Ben D. Kaplan, Chief Financial Officer