EXHIBIT 5



                                                July 24, 1996

        Securities and Exchange Commission
        450 Fifth Street, N.W.
        Judiciary Plaza
        Washington, D.C.  02549

             Re:  Registration Statement Relating to 200,000 Shares of
        the Common Stock,
                    $ .01 par value, of Thermo Voltek  Corp.             
                                              

        Ladies and Gentlemen:

             I am General Counsel to Thermo Voltek  Corp., a Delaware
        corporation (the "Company"), and have acted as counsel in
        connection with the registration under the Securities Act of
        1933, as amended (the "Act"), on the Registration Statement on
        Form S-8 (the "Registration Statement"), of 200,000 shares of the
        Company's Common Stock, $.01 par value per share (the "Shares"),
        issuable under the Company's Equity Incentive Plan (the "Plan").

             I have reviewed the corporate proceedings taken by the
        Company with respect to the authorization of the issuance of the
        Shares.  I have also examined and relied upon originals or
        copies, certified or otherwise authenticated to my satisfaction,
        of all corporate records, documents, agreements or other
        instruments of the Company and have made all investigations of
        law and have discussed with the Company's representatives all
        questions of fact that I have deemed necessary or appropriate.

             I have not made an independent review of the laws of any
        state or jurisdiction other than the Commonwealth of
        Massachusetts, the General Corporation Law of the State of
        Delaware and the federal securities laws of the United States of
        America.  Accordingly, I express no opinion as to the laws of any
        state or jurisdiction other than the laws of the Commonwealth of
        Massachusetts, the General Corporation Law of the State of
        Delaware and the federal securities laws of the United States of
        America.
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             Based upon and subject to the foregoing, I am of the opinion
        that the Shares issuable under the Plan have been duly authorized
        and, when issued upon receipt of consideration therefor and in
        accordance with the terms and conditions of the Plan, will be
        legally issued, fully paid and non-assessable.

             Pursuant to the requirements of the Act, I hereby consent to
        the filing of this opinion with the Securities and Exchange
        Commission in connection with the Registration Statement.

                                                  Very truly yours,



                                                  /s/ Seth H. Hoogasian
                                                  Seth H. Hoogasian