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                                                                 Exhibit 4.2

                               PERCEPTRONICS, INC.

                                     BY-LAWS

                                    ARTICLE I

                                  STOCKHOLDERS

         Section 1. ANNUAL MEETING. An annual meeting of the Stockholders,
for the election of directors and for the transaction of such other business
as may properly come before the meeting, shall be held at such place, on such
date, and at such time as the Board of Directors shall each year fix, which
date shall be within thirteen months subsequent to the later of the date of
Incorporation or the last annual meeting of stockholders.

         Section 2. SPECIAL MEETINGS. Special meetings of stockholders may be
called by the Board of Directors, the Chairman of the Board of Directors or
the President of the Corporation and shall be called by the Secretary of the
Corporation at the request in writing of holders of not less than 10% of the
total voting power of all outstanding securities of the Corporation then
entitled to vote. Such request shall state the purpose or purposes of the
proposed meeting.

         Section 3. NOTICE OF MEETINGS. Written notice of the place, date,
and time of all meetings of the stockholders and, in the case of a special
meeting, the purpose or purposes for which the meeting is called, shall be
given, not less than ten nor more than sixty (60) days before the date on
which the meeting is to be held, to a stockholder entitled to vote at such
meeting. except as otherwise provided herein or required by law (meaning,
here and hereinafter, as required from time to time by the Delaware General
Corporation Law or the Certificate of Incorporation of the Corporation).

         When a meeting is adjourned to another place, date or time, written
notice need not be given of the adjourned meeting if the place, date and time
thereof are announced at the meeting at which the adjournment is taken;
provided, however, that if the date of any adjourned meeting is more than
thirty (30) days after the date for which the meeting was originally noticed,
or if a new record date is fixed for the adjourned meeting, written notice of
the place, date, and time of the adjourned meeting shall be given in
conformity herewith. At any adjourned meeting, any business may be transacted
which might have been transacted at the original meeting.

         Section 4. QUORUM. At any meeting of the Stockholders, the holders
of a majority of all of the shares of the stock entitled to vote at the
meeting, present in person or by proxy, shall constitute a quorum for all
purposes, unless or except to the extent that the presence of a larger number
may be required by law.

         If a quorum shall fail to attend any meeting, the chairman of the
meeting or the holders of

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a majority of the shares of stock entitled to vote who are present, in person
or by proxy, may adjourn the meeting to another place, date or time.

         If a notice of any adjourned special meeting of stockholders is sent
to all stockholders entitled to vote thereat, stating that it will be held
with those present constituting a quorum, then except as otherwise required
by law, those present at such adjourned meeting shall constitute a quorum,
and all matters shall be determined by a majority of the votes cast at such
meeting.

         Section 5. ORGANIZATION. The Chairman of the Board or, in his or her
absence, the Chief Executive Officer of the Corporation or, in his or her
absence, such person as may be chosen by the holders of a majority of the
shares entitled to vote who are present, in person or by proxy, shall call to
order any meeting of the stockholders and act as chairman of the meeting. In
the absence of the Secretary of the Corporation, the secretary of the meeting
shall be such person as the chairman appoints.

         Section 6. CONDUCT OF BUSINESS. The chairman of any meeting of
stockholders shall determine the order of business and the procedure at the
meeting, including such regulation of the manner of voting and the conduct of
discussion as seem to him or her in order.

         Section 7. ACTION BY CONSENT. Unless otherwise restricted by the
Certificate of Incorporation, any action required to be taken at any annual
or special meeting of stockholders, or any action which may be taken at any
annual or special meeting of stockholders, may be taken without a meeting,
without prior notice and without a vote, if a consent in writing, setting
forth the action so taken, shall be signed by the holders of outstanding
securities of the Corporation having not less than the minimum number of
votes that would be necessary to authorize or take such action at a meeting
at which all securities entitled to vote thereon were present and voted.
Prompt notice of the taking of the Corporate action without a meeting by less
than unanimous written consent shall be given to those stockholders who have
not consented in writing.

         Section 8. PROXIES AND VOTING. At any meeting of the stockholders,
every stockholder entitled to vote may vote in person or by proxy authorized
by an instrument in writing filed in accordance with the procedure
established for the meeting.

         Each stockholder shall have one vote for every share of stock
entitled to vote which is registered in his or her name on the record date
for the meeting, except as otherwise provided herein or required by law.

         Every stockholder complying with this Section 8 and entitled to vote
at any election of directors may cumulate such stockholder's votes and give
one candidate a number of votes equal to the number of directors to be
elected multiplied by the number of votes to which the stockholder's shares
are normally entitled, or distribute the stockholder's votes on the same
principle among as many candidates as the shareholder thinks fit. No
stockholder shall be entitled to cumulate votes (i.e., cast for any candidate
a number of votes greater than the number of votes which such stockholder
normally is entitled to cast) unless such candidate or

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candidate's names have been placed in nomination prior to the voting and the
stockholder has given notice at the meeting prior to the voting of the
stockholder's intention to cumulate the stockholder's votes. If any one
stockholder has given such notice, all stockholders may cumulate their votes
for candidates in nomination.

         All voting, except in the election of directors or where otherwise
required by law, may be by a voice vote; provided, however, that upon demand
therefor by a stockholder entitled to vote or his or her proxy, a stock vote
shall be taken. All elections of directors and every stock vote shall be
taken by ballots, each of which shall state the name of the stockholder or
proxy voting and such other information as may be required under the
procedure established for the meeting. Every vote taken by ballots shall be
counted by an inspector or inspectors appointed by the chairman of the
meeting.

         All elections shall be determined by a plurality of the votes cast
and, except as otherwise required by law, all other matters shall be
determined by a majority of the votes cast.

         Section 9. STOCK LIST. A complete list of stockholders entitled to
vote at any meeting of stockholders, arranged in alphabetical order for each
class of stock and showing the address of each such stockholder and the
number of shares registered in his or her name, shall be open to the
examination of any such stockholder, for any purpose germane to the meeting,
during ordinary business hours for a period of at least ten (10) days prior
to the meeting, either at a place within the city where the meeting is to be
hold, which place shall be specified in the notice of the meeting, or if not
so specified, at the place where the meeting is to be held.

         The stock list shall also be kept at the place of the meeting during
the whole time thereof and shall be open to the examination of any such
stockholder who is present. This list shall presumptively determine the
identity of the stockholders entitled to vote at the meeting and the number
of shares held by each of them.

                                  ARTICLE II
                             BOARD OF DIRECTORS

         Section 1. NUMBER AND TERM OF OFFICE. The number of directors of the
Corporation shall not be less than five (5) nor more than nine (9) until
changed by amendment of the Certificate of Incorporation or by a by-law
amending this Section 1 duty adopted by holders of a majority of the
outstanding shares entitled to vote or by the Board of Directors. The exact
number of directors shall be fixed from time to time within the limits
specified in the Certificate of Incorporation or in this Section 1, by a
by-law or amendment thereof duly adopted by the stockholders or by the Board
of Directors. Subject to the foregoing provisions for changing the number of
directors, the number of directors of this Corporation has been fixed at slx
(6).

         All directors shall hold office until their respective successors
are duly elected and qualified or until a director's earlier death,
resignation or removal.

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         Section 2. VACANCIES AND NEWLY CREATED DIRECTORSHIPS. Subject to the
rights of the holders of any series of Preferred Stock then outstanding,
newly created directorships resulting from any increase in the authorized
number of directors or any vacancies in the Board of Directors resulting from
death, resignation, retirement, disqualification, removal from office or
other cause may be filled by a majority vote of the directors then in office,
though less than a quorum, or by a sole remaining director, and a director so
chosen shall hold office until such director's successor has been duly
elected and qualified or until such director's earlier death, resignation or
removal. No decrease in the number of directors constituting the Board of
Directors shall shorten the term of any incumbent director.

         Section 3. REMOVAL. Any director or the entire Board of Directors
may be removed, with or without cause, at any time by the affirmative vote of
the holders of not less than a majority of the total voting power of all
outstanding securities of the corporation entitled to vote; provided,
however, if less than the entire board of directors is to be removed, no
director may be removed without cause if the votes cast against his removal
would be sufficient to elect him if then cumulatively voted at an election of
the entire Board of Directors.

         Section 4. REGULAR MEETINGS. Regular meetings of the Board of
Directors shall be held at place or places, on such date or dates, and at
such time or times as shall have been established by the Board of Directors
and publicized among all directors. A notice of each regular meeting shall
not be required.

         Section 5. SPECIAL MEETINGS. Special meetings of the Board of
Directors may be called by one-third of the directors then in office (rounded
up to the nearest whole number) or by the chief executive officer and shall
be held at such place, on such date, and at such time as they or he or she
shall fix. Notice of the place, date, and time of each such special meeting
shall be given each director by whom it is not waived by mailing written
notice not less than live (5) days before the meeting or by telegraphing,
telexing or otherwise actually delivering the same not less than twenty- four
(24) hours before the meeting. Unless otherwise indicated in the notice
hereof, any and all business may be transacted at a special meeting.

         Section 6. QUORUM. At any meeting of the Board of Directors, a
majority of the total number of authorized directors shall constitute a
quorum for all purposes. If a quorum shall fail to attend any meeting, a
majority of those present may adjourn the meeting to another place, date, or
time, without further notice or waiver thereof.

         Section 7. PARTICIPATION IN MEETINGS BY CONFERENCE TELEPHONE.
Members of the Board of Directors, or of any committee thereof, may
participate in a meeting of such Board or committee by means of conference
telephone or similar communications equipment by means of which all persons
participating in the meeting can hear each other and such participation shall
constitute presence in person at such meeting.

         Section 8. CONDUCT OF BUSINESS; ACTION BY CONSENT. At any meeting of
the Board of Directors, business shall be transacted in such order and manner as
the Board may from time to

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time determine, and all matters shall be determined by the vote of a majority
of the directors present, except as otherwise provided herein or required by
law. Action may be taken by the Board of Directors without a meeting if all
members thereof consent thereto in writing, and the writing or writings are
filed with the minutes of proceedings of the Board of Directors.

         Section 9. POWERS. The Board of Directors may, except as otherwise
required by law, exercise all such powers and do all such acts and things as
may be exercised or done by the Corporation, including, without limiting the
generality of the foregoing, the unqualified power:

         (1)      To declare dividends from time to time in accordance with law;

         (2)      To purchase or otherwise acquire any property, rights or
privileges on such terms as it shall determine;

         (3)      To authorize the creation, making and issuance, in such
form as it may determine, of written obligations of every kind, negotiable or
non-negotiable, secured or unsecured, and to do all things necessary in
connection therewith;

         (4)      To remove any officer of the Corporation with or without
cause, and from time to time devolve the powers and duties of any officer
upon any other person for the time being;

         (5)      To confer upon any officer of the Corporation the power to
appoint, remove and suspend subordinate officers, employees and agents;

         (6)      To adopt from time to time such stock, option, stock
purchase, bonus or other compensation plans for directors, officers,
employees and agents of the Corporation and its subsidiaries as it may
determine;

         (7)      To adopt from time to time such insurance, retirement, and
other benefit plans for directors, officers, employees and agents of the
Corporation and its subsidiaries as it may determine; and

         (8)      To adopt from time to time regulations, not inconsistent
with these by-laws, for the management of the Corporation's business and
affairs.

         Section 10. COMPENSATION OF DIRECTORS. Directors, as such, may receive,
pursuant to resolution of the Board of Directors, fixed fees and other
compensation for their services as directors, including, without limitation,
their services as members of committees of the Board of Directors.

         Section 11. COMMITTEES OF THE BOARD OF DIRECTORS. The Board of
Directors may from time to time designate committees of the Board, with such
lawfully delegable powers and duties as it thereby confers, to serve at the
pleasure of the Board and shall, for those committees and any others provided
for herein, elect a director or directors to serve as the member or members,

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designating, if it desires, other directors as alternate members who may
replace any absent or disqualified member at any meeting of the committee.
Any committee so designated may exercise the power and authority of the Board
of Directors to declare a dividend, to authorize the issuance of stock or to
adopt a certificate of ownership and merger pursuant to Section 253 of the
Delaware General Corporation Law if the resolution which designates the
committee or a supplemental resolution of the Board of Directors shall so
provide. In the absence or disqualification of any member of any committee
and any alternate member in his place, the member or members of the committee
present at the meeting and not disqualified from voting, whether or not he or
she or they constitute a quorum, may by unanimous vote appoint another member
of the Board of Directors to act at the meeting in the place of the absent or
disqualified member.

         Each committee may determine the procedural rules for meeting and
conducting its business and shall act in accordance therewith, except as
otherwise provided herein or required by law. Adequate provision shall be
made for notice to members of all meetings; one-third of the authorized
members shall constitute a quorum unless the committee shall consist of one
or two members, in which event one member shall constitute a quorum; and all
matters shall be determined by a majority vote of the members present. Action
may be taken by any committee without a meeting if all members thereof
consent thereto in writing, and the writing or writings are filed with the
minutes of the proceedings of such committee.

                              ARTICLE III

                               OFFICERS

         Section 1. GENERALLY. The officers of the Corporation shall consist
of a Chairman of the Board and/or a Chief Executive Officer, President, one
or more vice Presidents, a Secretary, a Chief Financial Officer and such
other offices as may from time to time be appointed by the Board of
Directors. Officers shall be elected by the Board of Directors, which shall
consider that subject at its first meeting after every annual meeting of
stockholders. Each officer shall hold office until his or her successor is
elected and qualified or until his or her earlier resignation or removal. Any
number of offices may be held by the same person.

         Section 2. CHAIRMAN OF THE BOARD. The Chairman of the Board shall
preside at all meetings of stockholders and of the Board of Directors. The
Board at its discretion may designate the Chairman of the Board as chief
executive officer of the Corporation, in which event the Chairman of the
Board shall be charged with and shall have the discretion and supervision of
all its business and operations.

         Section 3. CHIEF EXECUTIVE OFFICER. The Chief Executive Officer of the
Corporation shall have general supervision, direction and control of the
business of the Company and shall, in the absence of the Chairman of the Board,
perform the duties of the Chairman of the Board. The Chief Executive Officer
shall have such other powers and duties as may be prescribed by the Board of
Directors or these by-laws.

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         Section 4.  PRESIDENT. The President of the Corporation shall
be the chief operation officer of the Corporation and shall have
responsibility for the day-to-day operation and management of the business of
the Corporation. The President shall have such other powers and duties as may
be prescribed by the Board of Directors or these by-laws.

         Section 5.  VICE PRESIDENT. Each Vice President shall have such
powers and duties as may be delegated to him or her by the Board of
Directors. One Vice President shall be designated by the Board to perform the
duties and exercise the powers of the President in the event of the
President's absence or disability.

         Section 6.  CHIEF FINANCIAL OFFICER. The Chief Financial Officer
shall have the responsibility for maintaining the financial records of the
Corporation and shall have custody of all monies and securities of the
Corporation. He or she shall make such disbursements of the funds of the
Corporation as are authorized and shall render from time to time an account
of all such transactions and of the financial condition of the Corporation.
The Chief Financial Officer shall also perform such other duties as the Board
of Directors may from time to time prescribe.

         Section 7.  SECRETARY. The Secretary shall issue all authorized
notices for, and shall keep minutes of, all meetings of the stockholders and
the Board of Directors. He or she shall have charge of the corporate books
and shall perform such other duties as the Board of Directors may from time
to time prescribe.

         Section 8.  DELEGATION OF AUTHORITY.  The Board of Directors may from
time to time delegate the powers or duties of any officer to any other
officers or agents, notwithstanding any provision thereof.

         Section 9.  REMOVAL. Any officer of the Corporation may be removed at
any time, with or without cause, by the Board of Directors.

         Section 10. ACTION WITH RESPECT TO SECURITIES OF OTHER CORPORATIONS.
Unless otherwise directed by the Board of Directors, the Chairman of the
Board or the Chief Executive Officer or any officer of the Corporation
authorized by them shall have the power to vote and otherwise act on behalf
of the Corporation, in person or by proxy, at any meeting of stockholders of
or with respect to any action of stockholders of any other corporation in
which this Corporation may hold securities and otherwise to exercise any and
all rights and powers which this Corporation may possess by reason of its
ownership of securities in such other corporation.

                              ARTICLE IV

                                STOCK

         Section 1. CERTIFICATES OF STOCK. Each stockholder shall be entitled to
a certificate signed by, or in the name of the Corporation by, the Chairman of
the Board , the President or a

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Vice President, and by the Secretary or an Assistant Secretary, or the Chief
Financial Officer, certifying the number of shares owned by him or her. Any
of or all the signatures on the certificate may be facsimile.

         Section 2. TRANSFERS OF STOCK. Transfers of stock shall be made only
upon the transfer books of the Corporation kept at an office of the Corporation
or by transfer agents designated to transfer shares of the stock of the
Corporation. Except where a certificate is issued in accordance with Section 4
of Article V of these by-laws, an outstanding certificate for the number of
shares involved shall be surrendered for cancellation before a new certificate
is issued therefor.

         Section 3. RECORD DATE. The Board of Directors may fix a record date
which shall not be more than sixty nor fewer than ten days before the date of
any meeting of stockholders, nor more than sixty days prior to the time for
the other action hereinafter described, as of which there shall be determined
the stockholders who are entitled: to notice of or to vote at any meeting of
stockholders or any adjournment thereof; to express consent to corporate
action in writing without a meeting; to receive payment of any dividend or
other distribution or allotment of any rights; or to exercise any rights with
respect to any change, conversion or exchange of stock or with respect to any
other lawful action.

         Section 4. LOST, STOLEN OR DESTROYED CERTIFICATES. In the event of
the loss, theft or destruction of any certificate of stock, another may be
issued in its place pursuant to such regulations as the Board of Directors
may establish concerning proof of such loss, theft or destruction and
concerning the giving of a satisfactory bond or bonds of indemnity.

         Section 5. REGULATIONS.  The issue, transfer, conversion and
registration of certificates of stock shall be governed by such other
regulations as the Board of Directors may establish.

                               ARTICLE V

                                NOTICES

         Section 1. NOTICES. Except as otherwise specifically provided herein
or required by law, all notices required to be given to any stockholder,
director, officer, employee or agent shall be in writing and may in every
instance be effectively given by hand delivery to the recipient hereof, by
depositing such notice in the mails, postage paid, or by sending such notice
by prepaid telegram, telex, rapifax or mailgram. Any such notice shall be
addressed to such stockholder, director, officer, employee or agent at his or
her last known address as the same appears on the books of the Corporation.
The time when such notice is received by such stockholder, director, officer,
employee or agent, or by any person accepting such notice on behalf of such
person, if hand delivered, or dispatched, if delivered through the mails or
by telegram, telex, rapifax or mailgram, shall be the time of the giving of
the notice.

         Section 2. WAIVERS. A written waiver of any notice, signed by a
stockholder, director, officer, employee or agent, whether before or after
the time the event for which notice is

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to be given, shall be deemed equivalent to the notice required to be given to
such stockholder, director, officer, employee or agent. Neither the business
nor the purpose of any meeting need be specified in such a waiver.

                              ARTICLE V

                            MISCELLANEOUS

         Section 1. FACSIMILE SIGNATURES. In addition to the provisions for
use of facsimile signatures elsewhere specifically authorized in these
by-laws, facsimile signatures elsewhere specifically authorized in these
by-laws, facsimile signatures of any officer or officers of the Corporation
may be used whenever and as authorized by the Board of Directors or a
committee thereof.

         Section 2. CORPORATE SEAL. The Board of Directors may provide a
suitable seal, containing the name of the Corporation, which seal shall be in
the charge of the Secretary. If and when so directed by the Board of
Directors or a committee thereof, duplicates of the seal may be kept and used
by the Chief Financial Officer or by an Assistant Secretary or Controller.

         Section 3. RELIANCE UPON BOOKS, REPORTS AND RECORDS. Each director,
each member of any committee designated by the Board of Directors, and each
officer of the Corporation shall, in the performance of his duties, be fully
protected in relying in good faith upon the books of account or other records
of the Corporation, including reports made to the Corporation by any of its
officers, by an independently certified public accountant, or by an appraiser
selected with reasonable care.

         Section 4. FISCAL YEAR.  The fiscal year of the Corporation shall be
as fixed by the Board of Directors.

         Section 5. TIME PERIODS. In applying any provision of these by-laws
which require that an act be done or not done a specified number of days
prior to an event or that an act be done during a period of a specified
number of days prior to an event, calendar days shall be used, the day of the
doing of the act shall be excluded, and the day of the event shall be
included.

                              ARTICLE VII

                  INDEMNIFICATION OF DIRECTORS AND OFFICERS

         Section 1. RIGHT TO INDEMNIFICATION. Each person who was or is made
a party or is threatened to be made a party to or is involved in any action,
suit or proceeding, whether civil, criminal, administrative or investigative
("proceeding"), by reason of the fact that he or she or a person of whom he
or she is the legal representative, is or was a director, officer or employee
of the Corporation or is or was serving at the request of the Corporation as
a director, officer or employee of another corporation, or of a partnership,
joint venture, trust or other enterprise,

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including service with respect to employee benefit plans, whether the basis
of such proceeding is alleged action in an official capacity as a director,
officer or employee or in any other capacity while serving as a director,
officer or employee, shall be indemnified and held harmless by the
Corporation to the fullest extent authorized by Delaware Law as the same
exists or may hereafter be amended (but, in the case of any such amendment,
only to the extent that such amendment permits the Corporation to provide
broader indemnification rights than said Law permitted the Corporation to
provide prior to such amendment) against all expenses, liability and loss
(including attorneys' fees, judgments, fines, ERISA excise taxes or
penalties, amounts paid or to be paid in settlement and amounts expended in
seeking indemnification granted to such person under applicable law, this
by-law or any agreement with the Corporation) reasonably incurred or suffered
by such person in connection therewith and such indemnification shall
continue as to a person who has ceased to be a director, officer or employee
and shall inure to the benefit of his or her heirs, executors and
administrators; provided however, that, except as provided in Section 2 of
this Article VII, the Corporation shall indemnify any such person seeking
indemnity in connection with an action, suit or proceeding (or part thereof)
initiated by such person only if such action, suit or proceeding (or part
thereof) was authorized by the Board of Directors of the Corporation. Such
right shall be a contract right and shall include the right to be paid by the
Corporation expenses incurred in defending any such proceeding in advance of
its final disposition; provided, however, that, if the Delaware General
Corporation Law then so requires, the payment of such expenses incurred by a
director or officer of the Corporation in his or her capacity as a director
or officer (and not in any other capacity in which service was or is rendered
by such person while a director or officer, including, without limitation,
service to an employee benefit plan) in advance of the final disposition of
such proceeding, shall be made only upon delivery to the Corporation of an
undertaking, by or on behalf of such director or officer, to repay all
amounts so advanced if it should be determined ultimately that such director
or officer is not entitled to be indemnified under this Section or otherwise.

         Section 2. RIGHT OF CLAIMANT TO BRING SUIT. If a claim under Section
1 is not paid in full by the Corporation within thirty (30) days after a
written claim has been received by the Corporation, the claimant may at any
time thereafter bring suite against the Corporation to recover the unpaid
amount of the claim and, if such suite is not frivolous or brought in bad
faith, the claimant shall be entitled to be paid also the expense of
prosecuting such claim. It shall be a defense to any such action (other than
an action brought to enforce a claim for expenses incurred in defending any
proceeding in advance of its final disposition where the required
undertaking, if any, has been tendered to this Corporation) that the claimant
has not met the standards of conduct which make it permissible under the
Delaware General Corporation Law for the Corporation to indemnify the
claimant for the amount claimed, but the burden of proving such defense shall
be on Corporation. Neither the failure of the Corporation (including its
Board of Directors, independent legal counsel, or its stockholders) to have
made a determination prior to the commencement of such action that
indemnification of the claimant is proper in the circumstances because he or
she has met the applicable standard of conduct set forth in the Delaware
General Corporation Law, nor an actual determination by the Corporation
(including its Board of Directors, independent legal counsel, or its
stockholders) that the claimant has not met such applicable standard conduct,
shall be a defense to the action or create a presumption that the

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claimant has not met the applicable standard of conduct.

         Section 3. INSURANCE. The Corporation may maintain insurance to the
extent reasonably available, at its expense, to protect itself and any such
director, officer, employee or agent of the Corporation or another
corporation, partnership, joint venture, trust or other enterprise against
any such expense, liability or loss, whether or not the Corporation would
have the power to indemnify such person against such expense, liability or
loss under the Delaware General Corporation Law.

         Section 4. EFFECT OF AMENDMENT. Any amendment, repeal or
modification of any provision of this Article VII by the stockholders and the
directors of the Corporation shall not adversely affect any right or
protection of a director or officer of the Corporation existing at the time
of such amendment, repeal or modification.

                              ARTICLE VIII

                               AMENDMENTS

         The Board of Directors is expressly empowered to adopt, amend or
repeal By-Laws of the Corporation. Any adoption, amendment or repeal of
By-Laws of the Corporation by the Board of Directors shall require the
approval of a majority of the total number of authorized directors (whether
or not there exist any vacancies in previously authorized directorships at
the time any resolution providing for adoption, amendment or repeal is
presented to the Board). The stockholders shall also have power to adopt,
amend or repeal the By-Laws of the Corporation.

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                AMENDMENT TO THE BYLAWS OF PERCEPTRONICS, INC.
                          (A DELAWARE CORPORATION)


         The Bylaws of Perceptronics, Inc., & Delaware corporation, are hereby
amended to read as follows:

         1. Section 2 of Article I is amended to read in full as follows:

            "SECTION 2, SPECIAL MEETINGS. Special meetings of stockholders
            may be called by the Board of Directors, the Chairman of the
            Board of Directors or the President of the Corporation and
            shall be called by the Secretary of the Corporation at the
            request in writing of holders of not less than 10% of the
            total voting power of all outstanding securities of the
            corporation then entitled to vote. No request by a stockholder
            shall be deemed properly made unless the request contains the
            information required for a notice of stockholder business in
            accordance with Section 11 of this Article I."

         2. The following Sections 10 and 11 are hereby added to Article I of
 the Bylaws:

            "SECTION 10 - NOTIFICATION--OF NOMINATIONS. Subject to the
            rights of the holders of any one or more series of Preferred
            Stock then outstanding, nominations for the election of
            directors may be made by the Board of Directors or by any
            stockholder entitled to vote for the election of directors.
            Any stockholder entitled to vote for the election of directors
            at an annual meeting or a special meeting called for the
            purpose of electing directors may nominate persons for
            election as directors at such meeting only if written notice
            of such stockholder's intent to make such nomination is
            delivered to, or mailed, postage prepaid, and received by, the
            Secretary of the Corporation at the principal office of the
            Corporation not later than (i) in the case of an annual
            meeting, ninety days prior to the anniversary date of the
            immediately preceding annual meeting; provided, however, that
            in the case of the 1988 annual meeting, such notice must be
            delivered to

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<PAGE>

            or received by the Secretary of the Corporation not later than the
            close of business on the tenth day following the date on which the
            Company first makes public disclosure of the date of the annual
            meeting and (ii) in the case of a special meeting, the close of
            business on the seventh business day following the date on which
            the Corporation first makes public disclosure of the date of the
            special meeting. Each notice given by such stockholder shall
            set forth: (A) the name and address of the stockholder who
            intends to make the nomination and of the person or persons to
            be nominated; (B) a representation that the stockholder is a
            holder of record of stock of the Corporation entitled to vote
            at such meeting (or if the record date for such meeting is
            subsequent to the date required for such stockholder notice, a
            representation that the stockholder is a holder of record at
            the time of such notice and intends to be a holder of record
            on the record date for such meeting), setting forth the number
            and class of shares so held, and intends to appear in person
            or by Proxy at the meeting to nominate the person or persons
            specified in the notice; (C) a description of all arrangements
            or understandings between the stockholder and each nominee and
            any other person or persons (naming such person or persons)
            pursuant to which the nomination or nominations are to be made
            by the stockholder; (D) such other information regarding each
            nominee proposed by such stockholder as would have been
            required to be included in a proxy statement filed pursuant to
            the proxy rules of the Securities and Exchange Commission had
            each nominee been nominated, or intended to be nominated, by
            the Board of Directors; and (E) the consent of each nominee to
            serve as a director of the Corporation if so elected. The
            Chairman of the meeting shall, if the facts warrant, determine
            and declare to the meeting that a nomination was not made in
            accordance with the provisions of this Section 10; and, if the
            Chairman should so determine and declare, the defective
            nomination shall he disregarded."

            "SECTION 11 - NOTIFICATION OF STOCKHOLDER BUSINESS. All

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<PAGE>

            business properly brought before any annual or special meeting
            of stockholders shall be transacted at such meeting. Business
            shall be deemed properly brought only if it is (i) specified
            in the notice of meeting (or any supplement thereto) given by
            or at the direction of the Board of Directors, (ii) otherwise
            properly brought before the meeting by or at the direction of
            the Board of Directors, or (iii) brought before the meeting by
            a stockholder of record entitled to vote at such meeting if
            written notice of such stockholder's intent to bring such
            business before such meeting is delivered to, or mailed,
            postage prepaid, and received by, the Secretary of the
            Corporation at the principal office of the Corporation not
            later than (i) in the case of an annual .meeting, ninety days
            prior to the anniversary date of the immediately preceding
            annual meeting; however, that in the case of the 1988 annual
            meeting, such notice must be delivered to or received by the
            Secretary of the Corporation not later than the close of
            business on the tenth day following the date on which the
            Company first makes public disclosure of the date of the
            annual meeting and (ii) in the case of a special meeting, the
            close of business on the seventh business day following the
            date on which the Corporation first makes public disclosure of
            the date of the special meeting. Each notice given by such
            stockholder shall set forth: (A) a brief description of the
            business desired to be brought before the meeting and the
            reasons for conducting such business at the meeting; (B) the
            name and address of the stockholder who intends to propose
            such business; (C) a representation that the stockholder is a
            holder of record of stock of the Corporation entitled to vote
            at such meeting (or if the record date for such meeting is
            subsequent to the date required for such stockholder notice, a
            representation that the stockholder is a holder of record at
            the time of such notice and intends to be a holder of record
            on the record date for such meeting), setting forth the number
            and class of shares so held, and intends to appear in person
            or by proxy at such meeting to propose such business; and (D)
            any material interest of the stockholder in such business. The
            Chairman of the meeting shall, if the facts

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<PAGE>

            warrant, determine and declare to the meeting that business was
            not properly brought before the meeting in accordance with the
            provisions of this Section 11; and, If the Chairman should so
            determine and declare, any such business not properly brought
            before the meeting shall not be transacted."

         The undersigned, being the duly elected and acting Secretary of
Perceptronics, Inc. hereby certifies that the foregoing amendments to the
Bylaws of Perceptronics, Inc. were duly approved by the Board of Directors at
a meeting held on July 27, 1988.

         IN WITNESS WHEREOF, the undersigned has hereunto subscribed her name
as of the 27th day of July, 1988.

                                             /s/ Sarah A. S. Goldberg
                                             -------------------------------
                                             Sarah A. S. Goldberg, Secretary


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<PAGE>

                          AMENDMENT TO THE BYLAWS
                                    OF
                            PERCEPTRONICS, INC.
                          (a Delaware corporation)


         The undersigned, being the duly elected and acting Secretary of
Perceptronics, Inc., hereby certifies that the following amendment to the
Bylaws of Perceptronics, Inc., a Delaware corporation, was duly adopted by
the Board of Directors at a meeting held on April 23, 1991.

         The first paragraph of Section 8, Article I of the Bylaws, as
amended, of Perceptronics, Inc. is hereby amended to read in full as follows:

            "Section 8. PROXIES AND VOTING.  At any meeting of the
            stockholders, any stockholder entitled to vote may vote in person
            or by proxy authorized in accordance with Section 212(c) of the
            Delaware General Corporation Law and filed with the Corporation in
            accordance with the procedure established for the meeting."

         IN WITNESS WHEREOF, the undersigned has hereunto subscribed her name
as of the 28 day of June, 1991.


                                       /s/ Sarah A. S. Goldberg
                                       -----------------------------------
                                        Sarah A.S. Goldberg, Secretary


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