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                                                                EXHIBIT 10.2

[COMERICA LOGO]

                                                VARIABLE RATE-INSTALLMENT NOTE

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AMOUNT         NOTE DATE             MATURITY DATE        TAX IDENTIFICATION #
$500,000.00     SEPTEMBER 1, 1996    OCTOBER 1, 2000      95-4070595
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For Value Received, the undersigned promise(s) to pay to the order of COMERICA
                                                                      --------
BANK-CALIFORNIA ("Bank"), at any office of the Bank in the State of California,
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FIVE HUNDRED THOUSAND AND NO/100  Dollars (U.S.) in installments of $10,417.00
---------------------------------                                   ------------
each [ ] INCLUSIVE OF [X] PLUS Interest on the unpaid balance from the date of
this Note at a per annum rate equal to the Bank's base rate from time to time
in effect PLUS  1.250  % per annum until maturity, whether by acceleration or
          ----- ------
otherwise, or until Default, as later defined, and after that at a default rate
equal to the rate of interest otherwise prevailing under this Note plus 3% per
annum (but in no event in excess of the maximum rate permitted by law).
Interest shall be calculated for the actual number of days the principal is
outstanding on the basis of a 360 day year if this Note evidences a business or
commercial loan or a 365 day year if a consumer loan. The Bank's "base rate" is
that annual rate of interest so designated by the Bank and which is changed by
the Bank from time to time. Interest rate changes will be effective for
Interest computation purposes as and when the Bank's base rate changes.
Installments of principal and accrued interest due under this Note shall be
payable on the 1ST day of each  MONTH   , commencing   NOVEMBER 1, 1996  , and
               ---            ---------              --------------------
the entire remaining unpaid balance of principal and accrued interest shall be
payable on the Maturity Date set forth above. If the frequency of principal and
interest installments is not otherwise specified, installments of principal and
interest due under this Note shall be payable monthly on the first day of each
month. 

In the event the periodic installments set forth above are inclusive of
interest, these installments are calculated at an assumed fixed interest rate
and an assumed amortization term. The amortization term ends on  OCTOBER 1, 2000
                                                                ----------------
(if left blank, the amortization terms ends on the Maturity Date). In the
event this Note evidences a business or commercial loan and the Bank's base
rate changes, the Bank, at its sole option, may from time to time recalculate
the periodic installment amount so that the remaining periodic installments
will fully amortize the remaining loan balance within the remaining
amortization term in equal installments at the interest rate then being charged
under this Note. THE UNDERSIGNED AGREE(S) TO PAY THE PERIODIC INSTALLMENTS AS
THEY MAY BE RECALCULATED BY THE BANK, AT THE BANK'S SOLE OPTION, FROM TIME TO
TIME AND ACKNOWLEDGE(S) THAT A RECALCULATION SHALL NOT AFFECT THE MATURITY DATE
OR THE OTHER TERMS AND PROVISIONS OF THIS NOTE. If this Note or any installment
under this Note shall become payable on a day other than a day on which the Bank
is open for business, this payment may be extended to the next succeeding
business day and interest shall be payable at the rate specified in this Note
during this extension. Any payments of principal in excess of the installment
payments required under this Note need not be accepted by the Bank (except as
required under applicable law), but if accepted shall apply to the installments
last falling due. A late installment charge equal to 5% of each late
installment may be charged on any installment payment not received by the Bank
within 10 calendar days after the installment due date, but acceptance of
payment of this charge shall not waive any default under this Note.

This Note and any other indebtedness and liabilities of any kind of the
undersigned (or any of them) to the Bank, and any and all modifications,
renewals or extensions of it, whether joint or several, contingent or absolute,
now existing or later arising, and however evidenced (collectively
"Indebtedness") are  secured by and the Bank is granted a security interest in
all items deposited in any account of any of the undersigned with the Bank and
by all proceeds of these items (cash or otherwise), all account balances of any
of the undersigned from time to time with the Bank, by all property of any of
the undersigned from time to time in the possession of the Bank and by any
other collateral, rights and properties described in each and every deed of
trust, mortgage, security agreement, pledge, assignment and other agreement
which has been, or will at any time(s) later be, executed by any (or all) of
the undersigned to or for the benefit of the Bank (collectively "Collateral").
Notwithstanding the above, (i) to the extent that any portion of the
indebtedness is a consumer loan, that portion shall not be secured by any deed
of trust or mortgage on or other security interest in any of the undersigned's
principal dwelling or in any of the undersigned's real property which is not a
purchase money security interest as to that portion, unless expressly provided
to the contrary in another place, or (ii) if the undersigned (or any of them)
has (have) given or give(s) Bank a deed of trust or mortgage covering real
property, that deed of trust or mortgage shall not secure this Note or any
other indebtedness of the undersigned (or any of them), unless expressly
provided to the contrary in another place.

If the undersigned (or any of them) or any guarantor under a guaranty of all or
part of the indebtedness ("guarantor") (a) fail(s) to pay this Note or any of
the indebtedness when due, by maturity, acceleration or otherwise, or fail(s) to
pay any indebtedness owing on a demand basis upon demand; or (b) fail(s) to
comply with any of the terms or provisions of any agreement between the
undersigned (or any of them) or any guarantor and the Bank; or (c) become(s)
insolvent or the subject of a voluntary or involuntary proceeding in bankruptcy,
or a reorganization, arrangement or creditor composition proceeding, (if a
business entity) cease(s) doing business as a going concern, (if a natural
person) die(s) or become(s) incompetent, (if a partnership) dissolve(s) or any
general partner of it dies, becomes incompetent or becomes the subject of a
bankruptcy proceeding or (if a corporation or a limited liability company) is
the subject of a dissolution, merger or consolidation; or (d) if any warranty or
representation made by any of the undersigned or any guarantor in connection
with this Note or any of the indebtedness shall be discovered to be untrue or
incomplete; or (e) if there is any termination, notice of termination, or breach
of any guaranty, pledge, collateral assignment or subordination agreement
relating to all or any part of the indebtedness; or (f) if there is any failure
by any of the undersigned or any guarantor to pay when due any of its
indebtedness (other than to the Bank) or in the observance or performance of any
term, covenant or condition in any document evidencing, securing or relating to
such indebtedness; or (g) if the Bank deems itself insecure, believing that the
prospect of payment of this Note or any of the indebtedness is impaired or shall
fear deterioration, removal or waste of any of the Collateral; or (h) if there
is filed or issued a levy or writ of attachment or garnishment or other like
judicial process upon the undersigned (or any of them) or any guarantor or any
of the Collateral, including without limit, any accounts of the undersigned (or
any of them) or any guarantor with the Bank, then the Bank, upon the occurrence
of any of these events (each a "Default"), may at its option and without prior
notice to the undersigned (or any of them), declare any or all of the
indebtedness to be immediately due and payable (notwithstanding any provisions
contained in the evidence thereof to the contrary), sell or liquidate all or any
portion of the Collateral, set off against the indebtedness any amounts owing by
the Bank to the undersigned (or any of them), charge interest at the default
rate provided in the document evidencing the relevant indebtedness and exercise
any one or more of the rights and remedies granted to the Bank by any agreement
with the undersigned (or any of them) or given to it under applicable law. In
addition, if this Note is secured by a deed of trust or mortgage covering real
property, then the trustor or mortgagor shall not mortgage or pledge the
mortgaged premises as security for any other indebtedness or obligations. This
Note, together with all other indebtedness secured by said deed of trust or
mortgage, shall become due and payable immediately, without notice, at the
option of the Bank, (a) if said trustor or mortgagor shall mortgage or pledge
the mortgaged premises for any other indebtedness or obligations or shall
convey, assign or transfer the mortgaged premises by deed, installment sale
contract or other instrument, or (b) if the title to the mortgaged premises
shall become vested in any other person or party in any manner whatsoever, or
(c) if there is any disposition (through one or more transaction(s)) of legal or
beneficial title to a controlling interest of said trustor or mortgagor. All
payments under this Note shall be in immediately available United States funds,
without setoff or counterclaim.

If this Note if signed by two or more parties (whether by all as makers or by
one or more as an accommodation party or otherwise), the obligations and
undertakings under this Note shall be that of all and any two or more jointly
and also of each severally. This Note shall bind the undersigned, and the
undersigned's respective heirs, personal representatives, successors and
assigns. 

The undersigned waive(s) presentment, demand, protest, notice of dishonor,
notice of demand or intent to demand, notice of acceleration or intent to
accelerate, and all other notices and agree(s) that no extension or indulgence
to the undersigned (or any of them) or release, substitution or nonenforcement
of any security, or release or substitution of any of the undersigned, any
guarantor or any other party, whether with or without notice, shall affect the
obligations of any of the undersigned. The undersigned waive(s) all defenses or
right to discharge available under Section 3-605 of the California Uniform
Commercial Code and waive(s) all other suretyship defenses or right to
discharge. The undersigned agree(s) that the Bank has the right to sell, assign,
or grant participations, or any interest, in any or all of the indebtedness, and
that, in connection with this right, but without limiting its ability to make
other disclosures to the full extent allowable, the Bank may disclose all
documents and information which the Bank now or later has relating to the
undersigned or the indebtedness. The undersigned agree(s) that the Bank may
provide information relating to this Note or to the undersigned to the Bank's
parent, affiliates, subsidiaries and service providers.
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The undersigned agree(s) to reimburse the holder or owner of this Note for any
and all costs and expenses (including without limit, court costs, legal
expenses and reasonable attorney fees, whether inside or outside counsel is
used, whether or not suit is instituted and, if suit is instituted, whether at
the trial court level, appellate level, in a bankruptcy, probate or
administrative proceeding or otherwise) incurred in collecting or attempting to
collect this Note or incurred in any other matter or proceeding relating to
this Note.

The undersigned acknowledge(s) and agree(s) that there are no contrary
agreements, oral or written, establishing a term of this Note and agree(s) that
the terms and conditions of  this Note may not be amended, waived or modified
except in a writing signed by an officer of the Bank expressly stating that the
writing constitutes an amendment, waiver or modification of the terms of this
Note. As used in this Note, the word "undersigned" means, individually and
collectively, each maker, accommodation party, indorser and other party signing
this Note in a similar capacity. If any provision of this Note is unenforceable
in whole or part for any reason, the remaining provisions shall continue to be
effective. THIS NOTE IS MADE IN THE STATE OF CALIFORNIA AND SHALL BE GOVERNED
BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF
CALIFORNIA, WITHOUT REGARD TO CONFLICT OF LAWS PRINCIPLES.

THE MAXIMUM INTEREST RATE SHALL NOT EXCEED THE HIGHEST APPLICABLE USURY CEILING.

THE UNDERSIGNED AND THE BANK ACKNOWLEDGE THAT THE RIGHT TO TRIAL BY JURY IS A
CONSTITUTIONAL ONE, BUT THAT IT MAY BE WAIVED. EACH PARTY, AFTER CONSULTING (OR
HAVING HAD THE OPPORTUNITY TO CONSULT) WITH COUNSEL OF THEIR CHOICE, KNOWINGLY
AND VOLUNTARILY, AND FOR THEIR MUTUAL BENEFIT, WAIVES ANY RIGHT TO TRIAL BY
JURY IN THE EVENT OF LITIGATION REGARDING THE PERFORMANCE OR ENFORCEMENT OF, OR
IN ANY WAY RELATED TO, THIS NOTE OR THE INDEBTEDNESS.

THIS VARIABLE RATE-INSTALLMENT NOTE IS SUBJECT TO THE TERMS OF A REVOLVING
CREDIT AGREEMENT DATED OCTOBER 6, 1993 AND ANY AND ALL AMENDMENTS THEREOF
INCLUDING BUT NOT LIMITED TO THE 5TH AMENDMENT TO REVOLVING CREDIT LOAN
AGREEMENT DATED MARCH 21, 1996.

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<S>                                    <C>                                                 <C>
                                       For Corporations, Partnerships, Trust, or Estates   

PACIFIC PRECISION LABORATORIES, INC.      /s/ Robert S. Hash                                    President
------------------------------------   By: ---------------------------------------         Its: ----------------------------------- 
OBLIGOR NAME TYPED/PRINTED             SIGNATURE OF                                        TITLE


9207 ETON AVENUE                          /s/ Leo Yoffe                                         Executive V.P./C.O.O./C.F.O.
------------------------------------   By: ---------------------------------------         Its: ----------------------------------- 
STREET ADDRESS                         SIGNATURE OF                                        TITLE


CHATSWORTH                                /s/ Dennis E. Valentine                               Secretary
------------------------------------   By: ---------------------------------------         Its: ----------------------------------- 
CITY                                   SIGNATURE OF                                        TITLE


CA                    91311                                                                               
------------------------------------   By: ---------------------------------------         Its: ----------------------------------- 
STATE               ZIP CODE           SIGNATURE OF                                        TITLE


                                       For Individuals or Sole Proprietorships
                                       Name(s) of Obligor(s) (Type or Print):              Signature(s) of Obligor(s):

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

------------------------------------   -------------------------------------------         ----------------------------------------
STREET ADDRESS

------------------------------------   -------------------------------------------         ----------------------------------------
CITY 

------------------------------------   -------------------------------------------         ----------------------------------------
STATE               ZIP CODE

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<S>                                   <C>                           <C>                     <C>                     <C>
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                                                                 FOR BANK USE ONLY             CCAR #
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Loan Officer Initials                Loan Group Name                     Obligor(s) Name

   BROCK MULLINS                       METRO SAN FERNANDO                         PACIFIC PRECISION LABORATORIES, INC.
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Loan Officer I.D. No.                 Loan Group No.                 Obligor #                Note #                Amount

   48252                                95779                          5882057501                                   $500,000.00
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