SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

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

                   AMENDMENT NO. 1 ON FORM 10-K/A TO FORM 10-K

    (mark one)
    [ X ] Annual Report Pursuant to Section 13 or 15(d) of the Securities
          Exchange Act of 1934 for the fiscal year ended January 3, 1998
    [   ] Transition Report Pursuant to Section 13 or 15(d) of the
          Securities Exchange Act of 1934

                          Commission file number 1-8002

                           THERMO ELECTRON CORPORATION
             (Exact name of Registrant as specified in its charter)
    Delaware                                                       04-2209186
    (State or other jurisdiction of                          (I.R.S. Employer
    incorporation or organization)                        Identification No.)

    81 Wyman Street, P.O. Box 9046
    Waltham, Massachusetts                                         02254-9046
    (Address of principal executive offices)                       (Zip Code)
       Registrant's telephone number, including area code: (781) 622-1000
           Securities registered pursuant to Section 12(b) of the Act:

          Title of each class       Name of each exchange on which registered
    ------------------------------- -----------------------------------------
    Common Stock, $1.00 par value            New York Stock Exchange
    Preferred Stock Purchase Rights

           Securities registered pursuant to Section 12(g) of the Act:
                                      None

    Indicate by check mark whether the Registrant (1) has filed all reports
    required to be filed by Section 13 or 15(d) of the Securities Exchange
    Act of 1934 during the preceding 12 months, and (2) has been subject to
    the filing requirements for at least the past 90 days. Yes [ X ] No [   ]
    Indicate by check mark if disclosure of delinquent filers pursuant to
    Item 405 of Regulation S-K is not contained herein, and will not be
    contained, to the best of the Registrant's knowledge, in definitive proxy
    or information statements incorporated by reference into Part III of this
    Form 10-K or any amendment to this Form 10-K. [ X ]

    The aggregate market value of the voting stock held by nonaffiliates of
    the Registrant as of January 30, 1998, was approximately $6,089,611,000.

    As of January 30, 1998, the Registrant had 159,173,807 shares of Common
    Stock outstanding.
                       DOCUMENTS INCORPORATED BY REFERENCE

    Portions of the Registrant's Annual Report to Shareholders for the year
    ended January 3, 1998, are incorporated by reference into Parts I and II.

    Portions of the Registrant's definitive Proxy Statement for the Annual
    Meeting of Shareholders to be held on June 2, 1998, are incorporated by
    reference into Part III.
PAGE

                                                                  FORM 10-K/A
                           THERMO ELECTRON CORPORATION
   Item 1.  Business
            --------

            (a) General Development of Business
                -------------------------------

            See attached.

            (c) Description of Business
                -----------------------

                (i) Principal Products and Services
                    -------------------------------

                    See attached.

   Item 14. Exhibits, Financial Statement Schedules, and Reports on Form 8-K
            ----------------------------------------------------------------

            (c) Exhibits
                --------

                13  Annual Report to Shareholders for the year ended January
                    3, 1998 (only those portions incorporated herein by
                    reference).

                23  Consent of Arthur Andersen LLP.






















                                        2PAGE

                                                                  FORM 10-K/A

    Item 1. Business
            --------

    (a) General Development of Business
        -------------------------------

        Thermo Electron Corporation and its subsidiaries (the Company or the
    Registrant) develop, manufacture, and market analytical and monitoring
    instruments; biomedical products including heart-assist devices,
    respiratory-care equipment, and mammography systems; paper recycling and
    papermaking equipment; alternative-energy systems; industrial process
    equipment; and other specialized products. The Company also provides a
    range of services that include industrial outsourcing, particularly in
    environmental-liability management, laboratory analysis, and
    metallurgical processing; and conducts advanced-technology research and
    development. The Company performs its business through divisions and
    wholly owned subsidiaries, as well as majority-owned subsidiaries that
    are partially owned by the public or by private investors.

        A key element in the Company's growth has been its ability to
    commercialize innovative products and services emanating from research
    and development activities conducted by the Company's various
    subsidiaries. The Company's strategy has been to identify business
    opportunities arising from social, economic, and regulatory issues, and
    to seek a leading market share through the application of proprietary
    technology. As part of this strategy, the Company continues to focus on
    the acquisition of complementary businesses that can be integrated into
    its existing core businesses to leverage access to new markets.

        The Company believes that maintaining an entrepreneurial atmosphere
    is essential to its continued growth and development. To preserve this
    atmosphere, the Company has adopted a strategy of spinning out certain of
    its businesses into separate subsidiaries and having these subsidiaries
    sell a minority interest to outside investors. The Company believes that
    this strategy provides additional motivation and incentives for the
    management of the subsidiaries through the establishment of subsidiary-
    level stock option incentive programs, as well as capital to support the
    subsidiaries' growth. The Company's wholly and majority-owned
    subsidiaries are provided with centralized corporate development,
    administrative, financial, and other services that would not be available
    to many independent companies of similar size. As of April 2, 1998, the
    Company had 28 subsidiaries that have sold minority equity interests, 23
    of which are publicly traded and 5 of which are privately held.

        The Company is a Delaware corporation and was incorporated in 1956.
    The Company completed its initial public offering in 1967 and was listed
    on the New York Stock Exchange in 1980.

    Forward-looking Statements

        Forward-looking statements, within the meaning of Section 21E of the
    Securities Exchange Act of 1934, are made throughout this Annual Report
    on Form 10-K. For this purpose, any statements contained herein that are
    not statements of historical fact may be deemed to be forward-looking
    statements. Without limiting the foregoing, the words "believes,"
    "anticipates," "plans," "expects," "seeks," "estimates," and similar

                                        3PAGE

                                                                  FORM 10-K/A

    expressions are intended to identify forward-looking statements. There
    are a number of important factors that could cause the results of the
    Company to differ materially from those indicated by such forward-looking
    statements, including those detailed under the heading "Forward-looking
    Statements" in the Registrant's 1997 Annual Report to Shareholders, which
    statements are incorporated herein by reference.













                                        4PAGE

                                                                  FORM 10-K/A

    Item 1. Business
            --------

    (c) Description of Business
        -----------------------

        (i) Principal Products and Services
            -------------------------------

    Instruments

        The Company, through its Thermo Instrument Systems Inc. subsidiary,
    is a worldwide leader in the development, manufacture, and marketing of
    instruments used to identify complex chemical compounds, toxic metals,
    and other elements in a broad range of liquids, solids, and gases, as
    well as to analyze air pollution and radioactivity. Thermo Instrument
    also provides instruments that control, monitor, image, inspect, and
    measure various industrial processes and life sciences phenomena.

        Thermo Instrument historically has expanded both through the
    acquisition of companies and product lines and through the internal
    development of new products and technologies. During the past several
    years, Thermo Instrument has completed a number of complementary
    acquisitions that have provided additional technologies, specialized
    manufacturing or product-development expertise, and broader capabilities
    in marketing and distribution.

        For example, in March 1997, Thermo Instrument acquired 95% of Life
    Sciences International PLC, a London Stock Exchange-listed company.
    Subsequently, Thermo Instrument acquired the remaining shares of Life
    Sciences' capital stock. Life Sciences manufactures laboratory science
    equipment, appliances, instruments, consumables, and reagents for the
    research, clinical, and industrial markets.

        In March 1996, Thermo Instrument completed the acquisition of a
    substantial portion of the businesses constituting the Scientific
    Instruments Division of Fisons plc, a wholly owned subsidiary of
    Rhone-Poulenc Rorer Inc. These businesses substantially added to Thermo
    Instrument's research, development, manufacture, and sale of analytical
    instruments to industrial and research laboratories worldwide. Certain of
    the Fisons businesses were since sold by Thermo Instrument to a number of
    its public subsidiaries that have complementary technologies and markets.

        Thermo Instrument adopted the Company's spinout strategy in an effort
    to more clearly focus its many instrumentation technologies on specific
    niche markets. To date, Thermo Instrument has completed initial public
    offerings of ThermoSpectra Corporation, ThermoQuest Corporation, Thermo
    Optek Corporation, Thermo BioAnalysis Corporation, Metrika Systems
    Corporation, Thermo Vision Corporation, and ONIX Systems Inc. Thermo
    Instrument's subsidiaries are outlined below:

        ThermoSpectra develops, manufactures, and markets precision imaging
    and inspection, temperature-control, and test and measurement
    instruments. These instruments are generally combined with proprietary
    operations and analysis software to provide industrial and research
    customers with integrated systems that address their specific needs.

                                        5PAGE

                                                                  FORM 10-K/A

        ThermoQuest is a leading provider of mass spectrometers, liquid
    chromatographs, and gas chromatographs for the pharmaceutical,
    environmental, and industrial marketplaces. These analytical instruments
    are used in the quantitative and qualitative chemical analysis of organic
    and inorganic compounds at ultratrace levels of detection. ThermoQuest
    also supplies scientific equipment for the preparation and preservation
    of chemical samples, and consumables for the chromatography industry.

        Thermo Optek is a worldwide leader in the development, manufacture,
    and marketing of analytical instruments that use a range of light- and
    energy-based techniques. Thermo Optek's instruments are used in the
    quantitative and qualitative chemical analysis of elements and molecular
    compounds in a variety of solids, liquids, and gases.

        Thermo BioAnalysis develops, manufactures, and markets instruments,
    consumables, and information-management systems used in biochemical
    research and production, as well as in clinical diagnostics. Thermo
    BioAnalysis focuses on three principal product areas: life sciences
    instrumentation and consumables, information-management systems, and
    health physics instrumentation.

        Metrika Systems manufactures process optimization systems that
    provide on-line, real-time analysis of the elemental composition of bulk
    raw materials in basic-materials production processes, including coal,
    cement, and minerals. In addition, Metrika Systems manufactures
    industrial gauging and process-control instruments and systems used
    principally by manufacturers of finished web materials, such as sheet
    metal, rubber, and plastic foils, to measure and control parameters such
    as thickness and coating weight of such materials.

        Thermo Vision, which became a public subsidiary of Thermo Instrument
    in December 1997, designs, manufactures, and markets a diverse array of
    photonics (light-based) products, including optical components, imaging
    sensors and systems, lasers, optically based instruments, opto-
    electronics, and fiber optics. These products are used in applications
    including medical diagnostics, semiconductor production, X-ray imaging,
    physics research, and telecommunications.

        ONIX Systems, which became a public subsidiary of Thermo Instrument
    in March 1998, designs, develops, markets, and services sophisticated
    field measurement instruments and on-line sensors for process-control
    industries, particularly oil and gas. Systems provide real-time data
    collection, analysis, and local control functions regarding the flow,
    level, density, or composition of a particular material.

        Thermo Instrument also has wholly owned businesses, including the
    Life Sciences Clinical Instrument Division, which provides an array of
    clinical laboratory equipment and consumables, and Thermo Monitoring
    Instruments, which produces instruments and complete systems for
    detecting and monitoring environmental pollutants from industrial and
    mobile sources, and for detecting radioactive contamination.

                                        6PAGE

                                                                  FORM 10-K/A

    Alternative-energy Systems

        The Company's Alternative-energy Systems segment includes the
    operation of independent (non-utility) power plants that operate using
    environmentally sound fuels and technologies, the development of
    engineered clean fuels, and the manufacture and sale of biopesticides.
    This segment also includes the manufacture, sale, and servicing of
    intelligent traffic-control systems, industrial refrigeration equipment;
    natural gas engines; packaged cooling and cogeneration systems; and steam
    turbines and compressors.

        Through its Thermo Ecotek Corporation subsidiary, the Company
    designs, develops, owns, and operates independent (non-utility) electric
    power-generation facilities that use environmentally responsible fuels,
    including agricultural and wood wastes, referred to as "biomass." Thermo
    Ecotek currently operates seven biomass facilities. Its facilities are
    developed and operated through joint ventures or limited partnerships in
    which it has a majority interest, or through wholly owned subsidiaries.

        Thermo Ecotek intends to pursue development of biomass and other
    power-generation projects both in the U.S. and overseas. In 1996, Thermo
    Ecotek formed a joint venture in Italy to develop, own, and operate
    biomass-fueled electric power facilities, and in January 1997, announced
    a joint agreement to expand two district energy centers in the Czech
    Republic. In the U.S., where the Company believes that utility
    deregulation may present opportunities for updating aging plants, Thermo
    Ecotek signed a $9.5 million agreement in November 1997 to purchase two
    deregulated plants in southern California for possible refurbishing and
    repowering.

        Thermo Ecotek is expanding beyond power generation into other
    products and processes that protect the environment. In August 1995,
    Thermo Ecotek, through two wholly owned subsidiaries, entered into a
    Limited Partnership Agreement with KFx Wyoming, Inc., a subsidiary of KFx
    Inc., to develop, construct, and operate a coal-beneficiation plant in
    Gillette, Wyoming. The facility employs patented "clean coal" technology
    to remove excess moisture and increase energy from subbituminous coal
    extracted from Wyoming's Powder River Basin.

        In May 1996, Thermo Ecotek entered the biopesticide business by
    acquiring the assets, subject to certain liabilities, of the biopesticide
    division of W.R. Grace & Co. (renamed Thermo Trilogy), which develops,
    manufactures, and markets environmentally friendly products for
    agricultural pest control. In January 1997, Thermo Trilogy acquired the
    assets of biosys, inc., a producer of pheromone, neem/azadiractin,
    nematodes, and virus-based biopesticide products, as well as
    disease-resistant sugar cane, and in November 1997, purchased the Bt
    biopesticide product line of Novartis AG.

        The Company, through its Thermo Power Corporation subsidiary,
    manufactures, markets, and services intelligent traffic-control systems,
    industrial refrigeration equipment, engines for vehicular and stationary
    applications, natural gas-fueled commercial cooling and cogeneration
    systems, and, through its privately held ThermoLyte Corporation

                                        7PAGE

                                                                  FORM 10-K/A

    subsidiary, is developing a line of gas-powered lighting products for
    commercialization.

        In November 1997, Thermo Power completed a cash tender offer for Peek
    plc, based in the U.K. Through Peek, the Company offers a range of
    intelligent traffic-control systems for urban traffic control, motorway
    management, and public transportation management in cities worldwide.
    Systems include traffic-signal synchronization systems to minimize
    congestion, variable message systems to advise drivers of accidents or
    construction, video systems to provide real-time analysis of traffic
    flows at intersections and on highways, as well as automatic
    toll-collection systems. Peek also has developed high-resolution video
    equipment to aid police officers in monitoring traffic violations.

        Through its industrial refrigeration business, Thermo Power supplies
    standard and custom-designed industrial refrigeration systems used
    primarily by the food-processing, petrochemical, and pharmaceutical
    industries. Thermo Power is also a supplier of both remanufactured and
    new commercial cooling equipment for sale or rental. The commercial
    cooling equipment is used primarily in institutions and commercial
    buildings, as well as by service contractors.

        Thermo Power also develops, manufactures, markets, and services
    gasoline engines for recreational boats, propane and gasoline engines for
    lift trucks, and natural gas engines for vehicles and stationary
    industrial applications; and designs, develops, markets, and services
    packaged cooling and cogeneration systems fueled principally by natural
    gas.

        The Company's Alternative-energy Systems segment also includes a
    U.K.-based manufacturer of steam turbines and compressors.

    Paper Recycling

        The Company designs, manufactures, and sells paper recycling and
    papermaking equipment and accessory products, and electroplating and
    aqueous cleaning systems.

        Through its Thermo Fibertek Inc. subsidiary, the Company is a leading
    designer and manufacturer of processing machinery, accessories, and
    water-management systems for the paper and paper recycling industries.
    Thermo Fibertek's custom-engineered systems remove debris, impurities,
    and ink from wastepaper, and process it into a fiber mix used to produce
    recycled paper. Thermo Fibertek's principal products include
    custom-engineered systems and equipment for the preparation of wastepaper
    for conversion into recycled paper, accessory equipment and related
    consumables important to the efficient operation of papermaking machines,
    and water-management systems essential for draining, purifying, and
    recycling process water.

        In May 1997, Thermo Fibertek acquired the majority of the assets,
    subject to certain liabilities, of the stock-preparation business of
    Black Clawson Company and certain of its affiliates. In August 1997, the
    Company acquired the remaining assets of the stock-preparation business

                                        8PAGE

                                                                  FORM 10-K/A

    of Black Clawson Company and such affiliates. This business, renamed
    Thermo Black Clawson, is a leading supplier of recycling equipment used
    in processing fiber for the manufacture of "brown paper," such as that
    used for corrugated boxes.

        In September 1996, Thermo Fibergen Inc. became a majority-owned,
    public subsidiary of Thermo Fibertek. Thermo Fibergen is developing and
    commercializing equipment and systems to recover materials from
    papermaking sludge generated by plants that produce virgin and recycled
    pulp and paper. Thermo Fibergen's GranTek Inc. subsidiary uses a patented
    process to convert papermaking sludge into granules that are used for
    applications including carriers for agricultural chemicals, oil and
    grease absorption, and catbox filler.

        Through a wholly owned subsidiary, the Company also manufactures
    electroplating systems and related waste-treatment equipment and
    accessories, as well as aqueous systems for cleaning metal parts without
    using ozone-damaging solvents.

    Biomedical Products

        The Company's Biomedical Products segment comprises a number of
    diverse medical products businesses, both wholly and publicly owned, that
    supply a wide range of medical systems and devices for diagnostic
    imaging, cardiovascular support, respiratory care, neurodiagnostics,
    sleep analysis, wireless patient monitoring, and blood management. The
    Company's biomedical products are provided to hospitals, clinics,
    universities, private-practice medical offices, and medical research
    facilities.

        Its wholly owned Thermo Biomedical group includes Bear Medical
    Systems, the business of which was acquired from Allied Healthcare
    Products, Inc. in October 1997. Bear Medical designs, manufactures, and
    markets respiratory products, primarily ventilators.

        Also part of the Company's Thermo Biomedical group are SensorMedics
    Corporation, a leading provider of systems for pulmonary function
    diagnosis and a producer of respiratory gas analyzers, physiological
    testing equipment, and automated sleep-analysis systems; and Medical Data
    Electronics, a manufacturer of patient-monitoring systems. Both companies
    were acquired in 1996.

        Nicolet Biomedical Inc., another wholly owned subsidiary of the
    Company, is a leading manufacturer of biomedical instruments for
    assessing muscle, nerve, sleep, hearing, and brain blood-flow disorders,
    various neurologic disorders, and for related work in clinical
    neurophysiology. In September 1997, Nicolet acquired IMEX Medical
    Systems, Inc., a leading manufacturer of products used to evaluate
    peripheral vascular disease, as well as products to detect fetal
    heartbeat. This subsidiary is now called Nicolet Vascular Inc.

        Another wholly owned subsidiary, Bird Medical Technologies, Inc.,
    develops, manufactures, and sells respiratory-care equipment and
    accessories and infection-control products to hospitals, subacute-care

                                        9PAGE

                                                                  FORM 10-K/A

    facilities, outpatient surgical centers, doctors, dentists, the military,
    and to other manufacturers.

        Thermo Cardiosystems Inc., a public subsidiary of Thermedics Inc.,
    has developed an implantable left ventricular-assist system (LVAS) called
    HeartMate(TM) that, when implanted alongside the natural heart, is
    designed to take over the pumping function of the left ventricle for
    patients whose hearts are too damaged or diseased to produce adequate
    blood flow. Thermo Cardiosystems has two versions of the LVAS: a
    pneumatic (or air-driven) system that can be controlled by either a
    bedside console or portable unit, and an electric system that features an
    internal electric motor powered by an external battery-pack worn by the
    patient.

        The air-driven HeartMate system has received both the European
    Conformity Mark and U.S. Food and Drug Administration (FDA) approval for
    commercial sale. The electric version of the LVAS, which also holds the
    CE Mark, is currently awaiting commercial approval by the FDA for use as
    a bridge to transplant. In Europe, the device is used both as a bridge to
    transplant and as an alternative to medical therapy.

        In December 1996, Thermo Cardiosystems acquired the business of
    Nimbus Medical, Inc., a research and development organization involved
    for more than 20 years in technology for ventricular-assist devices and
    total artificial hearts, including high-speed rotary blood pumps, which
    are relatively small and could potentially provide cardiac support in
    small adults and children.

        Also part of Thermo Cardiosystems is International Technidyne
    Corporation, a leading manufacturer of hemostasis-management products,
    including blood coagulation-monitoring instruments, and a supplier of
    skin-incision devices used to draw small blood samples precisely and with
    minimal discomfort.

        Trex Medical Corporation, a public subsidiary of ThermoTrex
    Corporation, designs, manufactures, and markets a range of medical
    imaging systems. It is the world's leading manufacturer of mammography
    equipment and minimally invasive digital breast-biopsy systems. Trex
    Medical also provides general-purpose and specialty radiographic systems,
    such as those used in the diagnosis and treatment of coronary artery
    disease and other vascular conditions.

        In early December, Trex Medical submitted a 510(k) application to the
    FDA seeking clearance to market its digital imaging system for
    mammography. The Company believes that an advantage of digital imaging is
    that radiologists can manipulate and enhance image quality to scrutinize
    subtle differences that may otherwise go undetected on film-based X-rays.
    If the FDA approves the digital imaging system for mammography
    applications, Trex Medical plans to develop its digital technology for
    use in certain of its other products.

        ThermoLase Corporation, also a public subsidiary of ThermoTrex,
    operates a network of spas that offer its patented SoftLight(R)
    hair-removal system, for which it received FDA clearance in April 1995.

                                       10PAGE

                                                                  FORM 10-K/A

    The SoftLight system uses a low-energy dermatology laser in combination
    with a lotion to remove hair. ThermoLase submitted a 510(k) application
    for its laser-based skin-retexturing system, based on data from clinical
    trials.

        ThermoLase currently has 14 Spa Thira locations in the U.S., with 3
    spas outside the U.S.: in Paris, France; Lugano, Switzerland; and Dubai,
    U.A.E. To complement its Spa Thira salons, ThermoLase has commenced a
    program to license the SoftLight hair-removal process to physicians for
    use in their practices. ThermoLase has established a number of joint
    ventures and other physician-licensing arrangements to market its
    SoftLight processes internationally.

        ThermoLase also manufactures and markets personal care products sold
    through department stores, salons, and spas, including the lotion that is
    used in the SoftLight hair-removal process.

        Trex Communications Corporation, a majority-owned, privately held
    subsidiary of ThermoTrex, is developing laser communications technology
    designed to transmit very large amounts of data quickly, and also designs
    and markets interactive information and voice-response systems, as well
    as automated calling equipment.

    Industrial Outsourcing

        Through its Thermo TerraTech Inc. subsidiary, the Company provides
    outsourcing services, primarily in environmental-liability management and
    infrastructure planning and design, with specialization in the areas of
    municipal and industrial water quality management, bridge and highway
    construction and reconstruction, and natural resource management. Thermo
    TerraTech also offers comprehensive environmental testing and analysis
    through a national network of laboratories serving the pharmaceutical,
    food, and environmental industries.

        Thermo Remediation Inc., a public subsidiary of Thermo TerraTech, is
    a national provider of outsourcing services for environmental management,
    including industrial, nuclear, and soil remediation, as well as
    waste-fluids recycling, primarily helping clients manage problems
    associated with environmental compliance, waste management, and the
    cleanup of sites contaminated with organic or toxic wastes.

        The Randers Group Incorporated, also a public subsidiary of Thermo
    TerraTech, provides comprehensive engineering and outsourcing services in
    such areas as water and wastewater treatment, highway and bridge
    projects, process engineering, construction management, and operational
    services.

        A privately held subsidiary of Thermo TerraTech, Thermo EuroTech
    N.V., provides remediation and recycling services in Europe. The Company
    treats oil-based contaminated soils and recycles waste oil and oily waste
    streams. In February 1998, Thermo EuroTech acquired a controlling
    interest in an Irish environmental services company that provides
    comprehensive in-plant waste management and recycling services to
    high-tech manufacturing firms in that country.

                                       11PAGE

                                                                  FORM 10-K/A


        In addition, metallurgical heat-treating services are provided by a
    wholly owned subsidiary of the Company for customers in the automotive,
    aerospace, defense, and other industries. The Company also provides,
    through another wholly owned business, metallurgical fabrication
    services, principally on high-temperature materials, for customers in the
    aerospace, medical, electronics, and nuclear industries.

    Advanced Technologies

        The Company's Advanced Technologies segment includes basic and
    applied research and development, often sponsored by the U.S. government,
    that is conducted with a goal of identifying viable commercial
    opportunities for new ventures. A number of its subsidiaries also provide
    various instrument systems, developed primarily for product
    quality-assurance applications in industrial, food and beverage,
    pharmaceutical, and electronics markets.

        The Company's ThermoTrex subsidiary conducts sponsored research and
    development with the goal of commercializing new products based on
    advanced technologies developed in its laboratories. Sponsored research
    and development, conducted principally for the U.S. government, includes
    basic and applied research in communications, avionics, X-ray detection,
    signal processing, advanced-materials technology, and lasers.

        ThermoTrex is currently developing a number of additional
    technologies that it believes may have future commercial potential. These
    include a passive microwave camera intended to "see" through clouds and
    fog to enhance safety in aerial navigation, a space surveillance system
    designed to produce high-resolution images of low-earth-orbit satellites,
    a rapid optical beam steering laser radar system, and direct digital
    imaging systems for medical equipment to improve image quality for
    earlier and more accurate clinical diagnoses.

        The Company's Thermo Coleman Corporation subsidiary provides systems
    engineering, technology support and information-technology services and
    products. Thermo Coleman also provides defense- and environmental-systems
    engineering, integration and analysis services, and advanced technology
    research and development, primarily to the U.S. government. Using
    expertise gained from its government contract work, Thermo Coleman
    designs, develops, and commercializes services and products in areas such
    as information technology and sensor and measurement systems for
    customers in industries including healthcare, education, aircraft
    production, government, utilities, and entertainment.

        Thermo Sentron Inc., a public subsidiary of Thermedics, designs and
    manufactures high-speed precision-weighing and inspection equipment for
    packaging lines and industrial production. Thermo Sentron serves two
    principal markets, packaged goods and bulk materials, both of which use
    its products to meet quality and productivity objectives. Customers for
    Thermo Sentron's checkweighers are in the food-processing,
    pharmaceutical, mail-order, and other packaged-goods businesses. Thermo
    Sentron also sells metal detectors with a patented self-test feature that
    are used to inspect packaged products for metal contamination to

                                       12PAGE

                                                                  FORM 10-K/A

    food-processing and pharmaceutical companies. Its bulk-materials product
    line includes conveyor-belt scales, solid level-measurement and
    conveyor-monitoring systems, and sampling systems, all sold to customers
    in the mining and material-processing industries, as well as to electric
    utilities, chemical, and other manufacturing companies.

        Thermedics Detection Inc., another public subsidiary of Thermedics,
    develops and manufactures high-speed on-line analysis systems used for
    product quality assurance in a variety of industrial processes, as well
    as for security. Thermedics Detection provides X-ray imaging systems that
    monitor a wide range of containers for fill volume, net volume, and
    package integrity, as well as systems that detect trace amounts of
    contaminants in refillable bottles, specifically for the beverage
    industry. For the beverage, food, cosmetic, and other industries,
    Thermedics Detection also makes instruments that use near-infrared
    spectroscopy to measure moisture and other product components, including
    fat, protein, solvents, and other substances in numerous consumer and
    industrial products. Thermedics Detection recently introduced an
    ultrahigh-speed gas chromatograph that permits manufacturers to conduct
    laboratory-quality analysis for near-on-line process-control
    applications.

        Thermo Voltek Corp., also a public subsidiary of Thermedics, designs,
    manufactures, and markets test instruments and a range of products
    related to power amplification, conversion, and quality. Thermo Voltek's
    power products are used in communications, broadcast, research, and
    medical imaging applications. Its test instruments allow manufacturers of
    electronic systems and integrated circuits to test for electromagnetic
    compatibility. On March 30, 1998, Thermedics approved a proposal to
    acquire, through a merger, all of the outstanding shares of common stock
    of Thermo Voltek that Thermedics does not own at a price of $7.00 per
    share in cash. The total transaction cost to Thermedics is estimated to
    be approximately $27 million, which includes approximately $5.25 million
    for the redemption of the outstanding Thermo Voltek 3 3/4 percent
    convertible subordinated debentures due 2000. The merger is contingent
    upon, among other things, the negotiation and execution of a definitive
    merger agreement; receipt by the Thermo Voltek board of directors of an
    opinion by an investment banking firm that Thermedics' offer is fair to
    Thermo Voltek shareholders (other than Thermedics and the Company) from a
    financial point of view; the approval of the Thermo Voltek board of
    directors upon recommendation of a special committee of its independent
    directors; and clearance by the Securities and Exchange Commission of the
    proxy materials regarding the proposed transaction. On March 31, 1998,
    two complaints naming the Company as a defendant, among others, regarding
    Thermedics' proposed acquisition of Thermo Voltek were filed in Delaware
    Chancery Court by two Thermo Voltek shareholders attempting to act on
    behalf of the other public shareholders of Thermo Voltek. The complaints
    allege, among other things, that the proposed price of $7.00 per share is
    unfair and grossly inadequate.  

        Through a wholly owned subsidiary, Thermedics manufactures
    electrode-based chemical-measurement products used in the agricultural,
    biomedical research, food processing, pharmaceutical, sewage treatment,
 
                                       13PAGE

                                                                  FORM 10-K/A

    and many other industries. In laboratories, manufacturing plants, and in
    the field, Thermedics' products permit these industries to determine the
    presence and amount of relevant chemicals. Thermedics also manufactures
    on-line process monitors used by power plants and semiconductor
    manufacturers to detect contaminants in high-purity water.


























                                       14
PAGE




                                                                  FORM 10-K/A
                           THERMO ELECTRON CORPORATION

                                   SIGNATURES

        Pursuant to the requirements of Section 13 or 15(d) of the Securities
    Exchange Act of 1934, the Registrant has duly caused this Amendment No. 1
    on Form 10-K/A to be signed on its behalf by the undersigned, thereunto
    duly authorized.

    Date: April 3, 1998
                                      THERMO ELECTRON CORPORATION


                                      By: Paul F. Kelleher
                                          --------------------------------
                                          Paul F. Kelleher
                                          Senior Vice President, Finance 
                                            and Administration