SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                   -------------------------------------------


                                    FORM 8-K


                                 CURRENT REPORT

                       Pursuant to Section 13 or 15(d) of
                       the Securities Exchange Act of 1934



                                 Date of Report
                       (Date of earliest event reported):

                                February 24, 1999

                    ----------------------------------------


                             THERMOTREX CORPORATION
             (Exact name of Registrant as specified in its charter)


Delaware                        1-10791                          52-1711436
(State or other               (Commission                   (I.R.S. Employer
jurisdiction of               File Number)               Identification Number)
incorporation or
organization)


10455 Pacific Center Court
San Diego, California                                                 92121 
(Address of principal executive offices)                           (Zip Code)


                                (619) 646-5300
                         (Registrant's telephone number
                              including area code)



<PAGE>









Item 5.     Other Events

      On February 24, 1999, the Registrant issued a press release announcing the
resignation of its chairman and chief executive officer, Gary S. Weinstein. Anne
Pol, a senior vice president of Thermo Electron  Corporation,  the  Registrant's
parent corporation, will serve as interim president of the Registrant, pending a
permanent replacement.  John T. Keiser, chief operating officer,  biomedical and
new technologies, of Thermo Electron Corporation, has been appointed chairman of
the Registrant.


Item 7.     Financial Statements, Pro Forma Financial Information and Exhibits

      (a)    Financial Statements of Business Acquired: not
            applicable.

      (b)   Pro Forma Financial Information: not applicable.

      (c)   Exhibits: not applicable.






<PAGE>




                                    SIGNATURE



      Pursuant to the  requirements of the Securities  Exchange Act of 1934, the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned, thereunto duly authorized, on this 24th day of February, 1999.



                                          THERMOTREX CORPORATION


                                          By: /s/ Theo Melas-Kyriazi
                                             Theo Melas-Kyriazi
                                             Chief Financial Officer
[{"type": "8-K", "sequence": "1", "description": "FORM 8-K", "secsgml_size_bytes": 2706}]
{"company-data": {"conformed-name": "THERMOTREX CORP", "cik": "0000875316", "assigned-sic": "3844", "irs-number": "521711436", "state-of-incorporation": "DE", "fiscal-year-end": "0930"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-10791", "film-number": "99548765"}, "business-address": {"street1": "10455 PACIFIC CENTER COURT", "city": "SAN DIEGO", "state": "CA", "zip": "92121-4339", "phone": "6196465300"}, "mail-address": {"street1": "81 WYMAN STREET", "city": "WALTHAM", "state": "MA", "zip": "02254"}, "former-company": {"former-conformed-name": "THERMO ELECTRON TECHNOLOGIES CORP/DE", "date-changed": "19600201"}}
SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                   -------------------------------------------

                                    FORM 8-K

                                 CURRENT REPORT

                       Pursuant to Section 13 or 15(d) of
                       the Securities Exchange Act of 1934

                                 Date of Report
                       (Date of earliest event reported):

                                February 24, 1999

                    ----------------------------------------

                             THERMOTREX CORPORATION
             (Exact name of Registrant as specified in its charter)

Delaware                        1-10791                          52-1711436
(State or other               (Commission                   (I.R.S. Employer
jurisdiction of               File Number)               Identification Number)
incorporation or
organization)

10455 Pacific Center Court
San Diego, California                                                 92121 
(Address of principal executive offices)                           (Zip Code)

                                (619) 646-5300
                         (Registrant's telephone number
                              including area code)
Item 5.     Other Events

      On February 24, 1999, the Registrant issued a press release announcing the
resignation of its chairman and chief executive officer, Gary S. Weinstein. Anne
Pol, a senior vice president of Thermo Electron  Corporation,  the  Registrant's
parent corporation, will serve as interim president of the Registrant, pending a
permanent replacement.  John T. Keiser, chief operating officer,  biomedical and
new technologies, of Thermo Electron Corporation, has been appointed chairman of
the Registrant.

Item 7.     Financial Statements, Pro Forma Financial Information and Exhibits

      (a)    Financial Statements of Business Acquired: not
            applicable.

      (b)   Pro Forma Financial Information: not applicable.

      (c)   Exhibits: not applicable.
SIGNATURE

      Pursuant to the  requirements of the Securities  Exchange Act of 1934, the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned, thereunto duly authorized, on this 24th day of February, 1999.

                                          THERMOTREX CORPORATION

                                          By: /s/ Theo Melas-Kyriazi
                                             Theo Melas-Kyriazi
                                             Chief Financial Officer