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                                                              EXHIBIT 10.142

[LOGO]                        SILICON VALLEY BANK             

                             ANTIDILUTION AGREEMENT



ISSUER:          ALPHA MICROSYSTEMS
ADDRESS:         3511 WEST SUNFLOWER
                 SANTA ANA, CALIFORNIA  92704

DATE:            JULY 10, 1995



THIS AGREEMENT is entered into as of the above date by and between SILICON
VALLEY BANK ("Purchaser"), whose address is 3000 Lakeside Drive, Santa Clara,
California  95054-2895, and the above Company, whose address is set forth
above.

                                    RECITALS

 A.   Concurrently with the execution of this Antidilution Agreement, the
Purchaser is purchasing from the Company a Warrant to Purchase Stock (the
"Warrant") pursuant to which Purchaser has the right to acquire from the
Company the Shares (as defined in the Warrant).

 B.   By this Antidilution Agreement, the Purchaser and the Company desire to
set forth the adjustment in the number of Shares issuable upon exercise of the
Warrant as a result of a Diluting Issuance (as defined in Exhibit A to the
Warrant).

 C.   Capitalized terms used herein shall have the same meaning as set forth in
the Warrant.

 NOW, THEREFORE, in consideration of the mutual promises, covenants and
conditions hereinafter set forth, the parties hereto mutually agree as follows:

 1.   DEFINITIONS.  As used in this Antidilution Agreement, the following terms
      have the following respective meanings:

 (a)  "Option" means any right, option, or warrant to subscribe for, purchase,
or otherwise acquire common stock or Convertible Securities.

 (b)  "Convertible Securities" means any evidences of indebtedness, shares of
stock, or other securities directly or indirectly convertible into or
exchangeable for common stock.

 (c)  "Issue" means to grant, issue, sell, assume, or fix a record date for
determining persons entitled to receive, any security (including Options),
whichever of the foregoing is the first to occur.

 (d)  "Additional Common Shares" means all common stock (including reissued
shares) issued (or deemed to be issued pursuant to Section 2) after the date of
the Warrant.  Additional Common Shares does not include, however, any common
stock issued in a transaction described in Sections 2.1 and 2.2 of the Warrant;
any common stock Issued upon conversion of preferred stock outstanding on the 
date of the Warrant; the Shares; or common stock Issued as incentive or in a 
nonfinancing transaction to employees, officers, directors, or consultants to 
the Company.

 (e)  The shares of common stock ultimately Issuable upon exercise of an Option
(including the shares of common stock ultimately Issuable upon conversion or
exercise of a Convertible Security Issuable pursuant to an Option) are deemed
to be Issued when the Option is Issued.  The shares of common stock ultimately
Issuable upon conversion or exercise of a Convertible Security (other than a
Convertible Security Issued pursuant to an Option) shall be deemed Issued upon
Issuance of the Convertible Security.

 2.   DEEMED ISSUANCE OF ADDITIONAL COMMON SHARES.  The shares of common stock
ultimately Issuable upon exercise of an Option (including the shares of common
stock ultimately Issuable upon conversion or exercise of a Convertible Security
Issuable pursuant to an Option) are deemed to be Issued when the Option is
Issued.  The shares of common stock ultimately Issuable upon conversion or
exercise of a Convertible Security (other than a Convertible Security Issued
pursuant to an Option) shall be deemed Issued upon Issuance of the Convertible
Security.  The maximum amount of common stock Issuable is determined without
regard to any future





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SILICON VALLEY BANK                                      ANTIDILUTION AGREEMENT


adjustments permitted under the instrument creating the Options or Convertible
Securities.

 3.   ADJUSTMENT OF WARRANT PRICE FOR DILUTING ISSUANCES.

 3.1  RATCHET ADJUSTMENT.  If the Company issues Additional Common Shares
after the date of the Warrant and the consideration per Additional Common Share
(determined pursuant to Section 9) is less than the Warrant Price in effect
immediately before such Issue, the Warrant Price shall be reduced to the lesser
of:

 (a)  the amount of such consideration per Additional Common Share; or

 (b)  if the Company's common stock is traded on a national securities exchange
or the National Association of Securities Dealers Automated Quotation System,
the last reported bid or sale price of the Company's common stock on the first
trading day following a public announcement of the Issuance.

 3.2  ADJUSTMENT OF NUMBER OF SHARES.  Upon each adjustment of the Warrant
Price, the number of Shares issuable upon exercise of the Warrant shall be
increased to equal the quotient obtained by dividing (a) the product resulting
from multiplying (i) the number of Shares issuable upon exercise of the Warrant
and (ii) the Warrant Price, in each case as in effect immediately before such
adjustment, by (b) the adjusted Warrant Price.

 3.3  SECURITIES DEEMED OUTSTANDING.  For the purpose of this Section 3, all
securities issuable upon exercise of any outstanding Convertible Securities or
Options, warrants, or other rights to acquire securities of the Company shall
be deemed to be outstanding.

 4.   NO ADJUSTMENT FOR ISSUANCES FOLLOWING DEEMED ISSUANCES.  No adjustment to
the Warrant Price shall be made upon the exercise of Options or conversion of
Convertible Securities.

 5.   ADJUSTMENT FOLLOWING CHANGES IN TERMS OF OPTIONS OR CONVERTIBLE
SECURITIES.  If the consideration payable to, or the amount of common stock
Issuable by, the Company increases or decreases, respectively, pursuant to the
terms of any outstanding Options or Convertible Securities, the Warrant Price
shall be recomputed to reflect such increase or decrease.  The recomputation
shall be made as of the time of the Issuance of the Options or Convertible
Securities.  Any changes in the Warrant Price that occurred after such Issuance
because other Additional Common Shares were Issued or deemed Issued shall also
be recomputed.

 6.   RECOMPUTATION UPON EXPIRATION OF OPTIONS OR CONVERTIBLE SECURITIES.  The
Warrant Price computed upon the original Issue of any Options or Convertible
Securities, and any subsequent adjustments based thereon, shall be recomputed
when any Options or rights of conversion under Convertible Securities expire
without having been exercised.  In the case of Convertible Securities or
Options for common stock, the Warrant Price shall be recomputed as if the only
Additional Common Shares Issued were the shares of common stock actually Issued
upon the exercise of such securities, if any, and as if the only consideration
received therefor was the consideration actually received upon the Issue,
exercise or conversion of the Options or Convertible Securities.  In the case
of Options for Convertible Securities, the Warrant Price shall be recomputed as
if the only Convertible Securities Issued were the Convertible Securities
actually Issued upon the exercise thereof, if any, and as if the only
consideration received therefor was the consideration actually received by the
Company (determined pursuant to Section 9), if any, upon the Issue of the
Options for the Convertible Securities.

 7.   LIMIT ON READJUSTMENTS.  No readjustment of the Warrant Price pursuant to
Sections 5 or 6 shall increase the Warrant Price more than the amount of any
decrease made in respect of the Issue of any Options or Convertible Securities.

 8.   30 DAY OPTIONS.  In the case of any Options that expire by their terms
not more than 30 days after the date of Issue thereof, no adjustment of the
Warrant Price shall be made until the expiration or exercise of all such
Options.

 9.   COMPUTATION OF CONSIDERATION.  The consideration received by the Company
for the Issue of any Additional Common Shares shall be computed as follows:

 (a)  Cash shall be valued at the amount of cash received by the Corporation,
excluding amounts paid or payable for accrued interest or accrued dividends.

 (b)  Property.  Property other than cash shall be computed at the fair market
value thereof at the time of the Issue as determined in good faith by the Board
of Directors of the Company.

 (c)  Mixed Consideration.  The consideration for Additional common Shares
Issued together with other property of the Company for consideration that
covers both shall be determined in good faith by the Board of Directors.

 (d)  Options and Convertible Securities.  The consideration per Additional
Common Share for Options and Convertible Securities shall be determined by
dividing:

 (i)  the total amount, if any, received or receivable by the Company for the
Issue of the Options or Convertible Securities, plus the minimum amount of
additional consideration (as set forth in the instruments relating thereto,
without regard to any provision contained therein for a subsequent adjustment
of such consideration) payable to the Company upon exercise of the Options or
conversion of the Convertible Securities, by

 (ii) the maximum amount of common stock (as set forth in the instruments
relating thereto, without regard to any provision contained therein for a
subsequent adjustment of


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SILICON VALLEY BANK                                      ANTIDILUTION AGREEMENT


such number) ultimately Issuable upon the exercise of such Options or the
conversion of such Convertible Securities.

 10.   GENERAL.

 10.1  GOVERNING LAW.  This Antidilution Agreement shall be governed in all
respects by the laws of the State of California as such laws are applied to
agreements between California residents entered into and to be performed
entirely within California.

 10.2  SUCCESSORS AND ASSIGNS.  Except as otherwise expressly provided herein,
the provisions hereof shall inure to the benefit of, and be binding upon, the
successors, assigns, heirs, executors and administrators of the parties hereto.

 10.3  ENTIRE AGREEMENT.  Except as set forth below, this Antidilution Agreement
and the other documents delivered pursuant hereto constitute the full and
entire understanding and agreement between the parties with regard to the
subjects hereof and thereof.

 10.4  NOTICES. ETC.  All notices and other communications required or permitted
hereunder shall be in writing and shall be mailed by first class mail, postage
prepaid, certified or registered mail, return receipt requested, addressed (a)
if to Purchaser at Purchaser's address as set forth in the heading to this
Agreement, or at such other address as Purchaser shall have furnished to the
Company in writing, or (b) if to the Company, at the Company's address set
forth in the heading to this Agreement, or at such other address as the Company
shall have furnished to the Purchaser in writing.

 10.5  SEVERABILITY.  In case any provision of this Antidilution Agreement shall
be invalid, illegal, or unenforceable, the validity, legality and
enforceability of the remaining provisions of this Antidilution Agreement shall
not in any way be affected or impaired thereby.

 10.6  TITLES AND SUBTITLES.  The titles of the sections and subsections of this
Agreement are for convenience of reference only and are not to be considered in
construing this Antidilution Agreement.

 10.7  COUNTERPARTS.  This Antidilution Agreement may be executed in any number
of counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

 COMPANY:

         ALPHA MICROSYSTEMS




         BY  DOUGLAS J. TULLIO
             ---------------------------------
             PRESIDENT OR VICE PRESIDENT



         BY  JOHN F. GLADE
             ---------------------------------
             SECRETARY OR ASS'T SECRETARY



 PURCHASER:

         SILICON VALLEY BANK




         BY  TERRY BESS
             ---------------------------------
         TITLE  VICE PRESIDENT
                ------------------------------








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