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                                                                    EXHIBIT 4.17


                          THIRD SUPPLEMENTAL INDENTURE

        This Third Supplemental Indenture, effective as of April 30, 1998 (the
"Supplemental Indenture"), is entered into by and between The Cerplex Group,
Inc. (f/k/a Aurora Electronics, Inc.), a corporation organized and existing
under the laws of the State of Delaware (the "Company"), and Chase Manhattan
Trust Company, National Association (the "Successor Trustee"), in order to
supplement and amend that certain Indenture, dated as of April 15, 1986, by and
between the Company and MTrust Corp., N.A., as Predecessor Trustee, as
supplemented by the First Supplemental Indenture dated as of December 1, 1987,
and the Second Supplemental Indenture dated as of November 30, 1992, each
relating to the 7-3/4% Convertible Subordinated Debentures due 2001, and as
further amended by a Tripartite Agreement dated as of January 17, 1990
appointing the Successor Trustee (collectively, the "Indenture"). Terms used
herein which are not separately defined shall have the meanings assigned to them
in the Indenture.

        WHEREAS, Section 11.01 of the Indenture provides that, without the
consent of the Debentureholders, the Company and the Successor Trustee may enter
into indentures supplemental to the Indenture to cure any ambiguity or to
correct or supplement any provision contained in the Indenture, provided such
action does not adversely affect the interests of the Debentureholders;

        WHEREAS, effective April 30, 1998, Aurora Electronics, Inc. changed its
name to The Cerplex Group, Inc.; and

        WHEREAS, the Company and the Successor Trustee desire to correct and
supplement the Indenture solely for the purposes of reflecting such name change
and clarifying that the company will remain obligated for the due and punctual
performance of all the terms, conditions and covenants of the Indenture;

        NOW, THEREFORE, BE IT RESOLVED, for and in consideration of the mutual
covenants contained herein, the parties hereto, for themselves and the benefit
of the Debentureholders without preference, priority or distinction among them,
agree as follows:

        1. For all purposes on or subsequent to April 30, 1998, all references
to Aurora Electronics, Inc. or Aurora as a party to the Indenture are hereby
deleted and replaced by The Cerplex Group, Inc. or Cerplex.

        2. The definition of Company contained in Section 1.02 of Article One of
the Indenture is hereby amended and shall read in its entirety as follows:

                "Company: The term "Company" shall mean The Cerplex Group, Inc.
        (formerly known as Aurora Electronics, Inc.), a Delaware corporation,
        and, subject to the provisions of Article Thirteen, shall also include
        its successors and assigns."


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        3. The Company remains obligated for the due and punctual payment of the
principal of and interest on all the Debentures and the due and punctual
performance and observance of all the covenants and conditions of the Indenture
to be performed or observed by the Company.

        4. Upon request of any party to this Supplemental Indenture, the other
party to this Supplemental Indenture shall execute and deliver such further
instruments and do such further acts as may reasonably be necessary or advisable
to more effectually carry out the purpose of this Supplemental Indenture.

        5. Except as supplemented hereby, the Indenture remains in full force
and effect in accordance with its terms.

        6. This Supplemental Indenture may be executed in one or more
counterparts, each of which when so executed shall be deemed to be an original,
but all such counterparts together shall constitute one and the same instrument.










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        IN WITNESS WHEREOF, the undersigned have executed this Supplemental
Indenture to be effective as of April 30, 1998.

ATTEST:                                    THE CERPLEX GROUP, INC.



By: /s/ Phil Pietrowski                    By: /s/ Steven L. Korby
    ------------------------------             --------------------------------
Name:  Phil Pietrowski,                    Name:  Steven L. Korby
Title: Assistant Secretary                 Title: Executive Vice President


ATTEST:                                    CHASE MANHATTAN TRUST         
                                               COMPANY, NATIONAL ASSOCIATION,
By:                                        as Successor Trustee to Mellon
    ------------------------------             Bank, F.S.B.,
                                           as Successor Trustee to KeyBank
                                               National Association,
                                           as Successor Trustee to Society 
                                               National Bank, 
                                           as Successor Trustee




                                           By:
                                               --------------------------------

                                           Name:
                                                 ------------------------------

                                           Title:
                                                  -----------------------------






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