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Exhibit 10.13 - Promissory Note for $500,000 dated September 27, 2004.

                                 PROMISSORY NOTE
$500,000                                                           Sept 27, 2004

FOR VALUE RECEIVED, Amistar Corporation, a California corporation ("MAKER"),
hereby unconditionally promises to pay to the order of Gordon S. Marshall, an
individual ("LENDER"), in lawful money of the United States of America and in
immediately available funds, the principal sum of Five hundred Thousand
($500,000) (the "PRINCIPAL AMOUNT"), together with accrued and unpaid interest
thereon, each due and payable on the dates and in the manner set forth below.

1)       INTEREST RATE. Subject to the terms hereof, the rate of interest shall
         be seven percent (7.0%) per annum (the "INTEREST RATE"). Interest shall
         be calculated on the basis of a 360-day year for the actual number of
         days elapsed.

2)       PAYMENT SCHEDULE. Subject to Sections 3 and 6 below, Maker shall pay
         the principal and interest in accordance with the payment schedule set
         forth below. All payments shall be applied first to any charges due
         hereunder, then to accrued interest, and then to the principal balance.

         a)       No amounts shall be due or payable prior to December 31, 2004.

         b)       The entire outstanding Principal Amount and all accrued
                  interest shall be due and payable in full on December 31, 2004
                  (the "MATURITY DATE").

3)       PREPAYMENTS.

         (a)      This Note may be prepaid in whole or in part at any time
                  without premium or penalty.

         (b)      All amounts outstanding under this Note shall be prepaid in
                  full immediately prior to (i) Maker's dissolution or
                  liquidation, or (ii) the acquisition by a third party of all
                  or substantially all of Maker's capital stock, equity
                  interests or assets.

         (c)      The Prepayment shall be exercised by written notice. Such
                  notice shall identify the Principal Amount ("PREPAYMENT
                  PRINCIPAL") and the interest ("PREPAYMENT INTEREST" and,
                  together with the Prepayment Principal, the "PREPAYMENT
                  AMOUNT") outstanding under this Note and shall notify Maker of
                  the time, place and date for settlement of such repayment,
                  which shall be scheduled by Lender within fifteen (15) days
                  following the date of such notice.

4)       PLACE OF PAYMENT. All amounts payable hereunder shall be made at the
         place of payment specified in writing by Lender.

5)       SUBORDINATION This note shall be subordinated to Makers obligations in
         that certain Reimbursement Agreement, Dated as of October 1, 1995, as
         amended (the "Reimbursement Agreement").



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6)       DEFAULT. Each of the following events shall be an "EVENT OF DEFAULT"
         hereunder:

         (a)      Maker fails to pay timely any of the principal, interest or
                  other amounts due under this Note on the date the same become
                  due and payable;

         (b)      Maker files any petition or commences any case or other
                  proceeding with respect thereto for relief under any
                  bankruptcy, reorganization, arrangement, insolvency,
                  readjustment of debt, liquidation or moratorium law or any
                  other law for the relief of, or relating to, debtors, now or
                  hereafter in effect, or makes any assignment for the benefit
                  of creditors, or admits in writing its inability to pay or
                  generally fails to pay its debts as they mature or become due,
                  or Maker dissolves or ceases to continue to exist, or takes
                  any corporate action in furtherance of any of the foregoing;
                  or

         (c)      an involuntary petition is filed or any case or other
                  proceeding is commenced against Maker (unless such petition is
                  dismissed or discharged within sixty (60) days) under any
                  bankruptcy, reorganization, arrangement, insolvency,
                  adjustment of debt, liquidation or moratorium statute now or
                  hereafter in effect, or a custodian, receiver, trustee,
                  liquidator, assignee for the benefit of creditors (or other
                  similar official) is applied for or appointed for Maker or is
                  applied for or appointed to take possession, custody or
                  control of any property of Maker.

7)       REMEDIES. Upon the occurrence and during the continuance of an Event of
         Default hereunder and subject to the subordination provisions
         in Section 5:

         i)       all unpaid principal, accrued interest and other amounts owing
                  hereunder shall, at the option of Lender (and, in the case of
                  an Event of Default pursuant to Section 6(b) or (c) above,
                  automatically) be immediately due, payable and collectible by
                  Lender pursuant to applicable law; and

         ii)      Lender may exercise any and all rights and remedies it may
                  have under this Note and/or under applicable law.

         iii)     All rights and remedies shall be cumulative and not exclusive.
                  The failure of Lender to exercise all or any of its rights,
                  remedies, powers or privileges hereunder or any other
                  agreement or applicable law in any instance shall not
                  constitute a waiver thereof in that or any other instance.

8)       EXPENSES. If the payment of principal or interest of this Note is not
         paid when due, an Event of Default shall have occurred, or Maker
         otherwise breaches its obligations under this Note, Maker shall pay
         reasonable attorneys' fees to Lender together with reasonable costs and
         expenses of collection, including, without limitation, any attorneys'
         fees, costs and expenses relating to any proceedings with respect to
         the bankruptcy, reorganization, insolvency, readjustment of debt,
         dissolution or liquidation of Maker or any party to any agreement or
         instrument securing this Note.


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9)       MAXIMUM RATE. All agreements which either are now or which shall become
         agreements between Maker and the holder of this Note are hereby
         expressly limited so that in no contingency or event whatever, whether
         by reason of deferment or advancement of the indebtedness represented
         by this Note, acceleration of the maturity date of this Note, or
         otherwise, shall the amount paid or agreed to be paid to the holder of
         this Note for the use, forbearance or detention of the indebtedness
         evidenced hereby exceed the maximum amount of interest permissible
         under applicable law. If at any time, from any circumstance whatsoever,
         fulfillment of any provision of this Note or any other agreement
         between Maker and the holder hereof, shall result in or involve
         payments or performance which would exceed the maximum legal interest
         rate, then, IPSO FACTO, the obligation to be fulfilled shall be reduced
         so as not to exceed said maximum legal interest rate.

10)      WAIVER. Maker, for itself and its legal representatives, successors and
         assigns, hereby expressly waives demand, presentment, notice of
         dishonor, protest and notice of protest, and all other demands and
         notices in connection with the delivery, acceptance, performance,
         default or enforcement of this Note and agrees that any extension,
         renewal or postponement of the time of payment or any other indulgence
         to, or release of any person now or hereafter obligated for the payment
         of this Note shall not affect Maker's liability hereunder.


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         IN WITNESS WHEREOF, this Note has been duly executed as of the date
first set forth above.

                                MAKER:

                                Amistar Corporation, a California Corporation

                                By:    /s/ Gregory Leiser

                                Name:  Gregory Leiser

                                Title: Vice President Finance and CFO
ATTEST:

By:    /s/ Linda Flanagan

Name:  Linda Flanagan

Title: Accounting staff


Statements contained in this release, which are not purely historical, are
forward-looking statements within the meaning of the Private Securities
Litigation Reform Act of 1995 and are subject to risks and uncertainties such as
those described in the Company's Annual Report on Form 10-K. Actual results may
differ materially from anticipated results.

Amistar Corporation provides industrial automation solutions and
contract-manufacturing services. The Company designs, develops, manufactures,
markets and services a variety of automated equipment used to assemble
electronic components and product identification media to printed circuit boards
and other assemblies. In addition, the Company provides design and manufacturing
resources to create customized factory automation equipment and other products
according to customers' specification in a broad range of industries. The
Company also provides contract-manufacturing services to companies who outsource
the manufacturing of their electronic products. Through its subsidiary, ddn
Corporation, the Company provides automated point-of-sale machines that control
the dispensing of securely stored items such as consumer products, developed
photographs, medications and finished prescriptions to retail customers.

Additional information about Amistar is available at www.amistar.com and ddn
Corporation at www.ddncorp.com


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