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                                                                   EXHIBIT 10.23
[BANK OF AMERICA LOGO]

                                PROMISSORY NOTE

BORROWER: Trio-Tech International         LENDER: Bank of America, N.A.
          KTS Incorporated                        CLSC-Commercial Banking (LA)
          14731 Califa Street                     CA9-703-11-11
          Van Nuys, CA 91411                      333 South Beaudry Avenue,
                                                  11th Floor
                                                  Los Angeles, CA 90017-1486

PRINCIPAL AMOUNT: $3000,000.00                  DATE OF NOTE: SEPTEMBER 20, 2002

PROMISE TO PAY. Trio-Tech International and KTS Incorporated ("Borrower")
jointly and severally promise to pay to Bank of America, N.A. ("Lender"), or
order, in lawful money of the United States of America, the principal amount of
Three Hundred Thousand & 00/100 Dollars ($300,000.00) or so much as may be
outstanding, together with interest on the unpaid outstanding principal balance
of each advance. Interest shall be calculated from the date of each advance
until repayment of each advance.

PAYMENT. Borrower will pay this loan in one payment of all outstanding principal
plus all accrued unpaid interest on October 1, 2003. In addition, Borrower will
pay regular monthly payments of all accrued unpaid interest due as of each
payment date, beginning October 1, 2002, with all subsequent interest payments
to be due on the same day of each month after that. Unless otherwise agreed or
required by applicable law, payments will be applied first to any unpaid
collection costs and any late charges, then to any unpaid interest, and any
remaining amount to principal. The annual interest rate for this Note is
computed on a 365/360 basis; that is, by applying the ratio of the annual
interest rate over a year of 360 days, multiplied by the outstanding principal
balance, multiplied by the actual number of days the principal balance is
outstanding. Borrower will pay Lender at Lender's address shown above or at such
other place as Lender may designate in writing.

VARIABLE INTEREST RATE. The interest rate on this Note is subject to change from
time to time based on changes in an index which is the rate of interest publicly
announced from time to time by the Lender as its Prime Rate. The Prime Rate is
set by the Lender based on various factors, including the Lender's costs and
desired return, general economic conditions and other factors, and is used as a
reference point for pricing some loans. The Lender may price loans to its
customers at, above, or below the Prime Rate. Any change in the Prime Rate shall
take effect at the opening of business on the day specified in the public
announcement of a change in the Lender's Prime Rate (the "Index"). The Index is
not necessarily the lowest rate charged by Lender on its loans and is set by
Lender in its sole discretion. If the Index becomes unavailable during the term
of this loan, Lender may designate a substitute Index after notifying Borrower.
Lender will tell Borrower the current Index rate upon Borrower's request. The
interest rate change will not occur more often than each date of such change in
the index. Borrower understands that Lender may make loans based on other rates
as well. The interest rate to be applied to the unpaid principal balance of this
Note will be at a rate of 0.500 percentage points over the Index. NOTICE: Under
no circumstances will the interest rate on this Note be more than the maximum
rate allowed by applicable law.

PREPAYMENT. Borrower may pay without penalty all or a portion of the amount owed
earlier than it is due. Early payments will not, unless agreed to by Lender in
writing, relieve Borrower of Borrower's obligation to continue to make payments
of accrued unpaid interest. Rather, early payments will reduce the principal
balance due. Borrower agrees not to send Lender payments marked "paid in full,"
"without recourse", or similar language. If Borrower sends such a payment,
Lender may accept it without losing any of Lender's rights under this Note, and
Borrower will remain obligated to pay any further amount owed to Lender. All
written communications concerning disputed amounts, including any check or other
payment instrument that indicates that the payment constitutes "payment in full"
of the amount owed or that is tendered with other conditions or limitations or
as full satisfaction of a disputed amount must be mailed or delivered to: Bank
of America, N.A., CA9-703-11-11, 333 South Beaudry Avenue, 11th Floor Los
Angeles, CA 90017-1486.

LATE CHARGE. If a payment is 15 days or more late. Borrower will be charged
4.000% of the unpaid portion of the regularly scheduled payment.

INTEREST AFTER DEFAULT. Upon Borrower's failure to pay all amounts declared due
pursuant to this section, including failure to pay upon final maturity, Lender,
at its option, may, if permitted under applicable law, increase the variable
interest rate on this Note to 6,500 percentage points over the Index.

DEFAULT. Each of the following shall constitute an event of default ("Event of
Default") under this Note:

         PAYMENT DEFAULT. Borrower fails to make any payment when due under this
         Note.

         OTHER DEFAULTS. Borrower falls to comply with or to perform any other
         term, obligation, covenant or condition contained in this Note or in
         any of the related documents or to comply with or to perform any term,
         obligation, covenant or condition contained in any other agreement
         between Lender and Borrower.

         DEFAULT IN FAVOR OF THIRD PARTIES. Borrower of any Grantor defaults
         under any loan, extension of credit, security agreement, purchase or
         sales agreement, or any other agreement, in favor of any other creditor
         or person that may materially affect any of Borrower's property of
         Borrower's ability to repay this Note or perform Borrower's obligations
         under this Note or any of the related documents.

         FALSE STATEMENTS. Any warranty, representation or statement made or
         furnished to Lender by Borrower or on Borrower's behalf under this Note
         or the related documents is false or misleading in any material
         respect, either now or at the time made or furnished or becomes false
         or misleading at any time thereafter.

         INSOLVENCY. The dissolution or termination of Borrower's existence as a
         going business, the insolvency of Borrower, the appointment of a
         receiver for any part of Borrower's property, any assignment for the
         benefit of creditors, any type of creditor workout, or the commencement
         of any proceeding under any bankruptcy or insolvency laws by or against
         Borrower.

         CREDITOR OR FORFEITURE PROCEEDINGS. Commencement of foreclosure or
         forfeiture proceedings, whether by judicial proceeding, self-help,
         repossession or any other method, by any creditor of Borrower or by any
         governmental agency against any collateral securing the loan. This
         includes a garnishment of any of Borrower's accounts, including deposit
         accounts, with Lender. However, this Event of Default shall not apply
         if there is a good faith dispute by Borrower as to the validity or
         reasonableness of the claim which is the basis of the creditor or
         forfeiture proceeding and if Borrower gives Lender written notice of
         the creditor or forfeiture proceeding and deposits with Lender monies
         or a surety bond for the creditor or forfeiture proceeding, in an
         amount determined by Lender, in its sole discretion, as being an
         adequate reserve or bond for the dispute.

         EVENTS AFFECTING GUARANTOR. Any of the preceding events occurs with
         respect to any guarantor, endorser, surety, or accommodation party of
         any of the indebtedness or any guarantor, endorser, surety, or
         accommodation party dies or becomes incompetent, or revokes or disputes
         the validity of, or liability under, any guaranty of the indebtedness
         evidenced by this Note.

         CHANGE IN OWNERSHIP. Any change in ownership of twenty-five percent
         (25%) or more of the common stock of Borrower.

         ADVERSE CHANGE. A material adverse change occurs in Borrower's
         financial condition, or Lender believes the prospect of payment or


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                                 PROMISSORY NOTE
                                   (CONTINUED)                            PAGE 2

     performance of this Note is impaired.

LENDER'S RIGHTS. Upon default, Lender may declare the entire unpaid principal
balance on this Note and all accrued unpaid interest immediately due, and then
Borrower will pay that amount.

ATTORNEYS' FEES; EXPENSES. Lender may hire or pay someone else to help collect
this Note if Borrower does not pay. Borrower will pay Lender that amount. This
includes, subject to any limits under applicable law, Lender's attorneys' fees
and  Lender's legal expenses, whether or not there is a lawsuit, including
attorneys' fees, expenses or bankruptcy proceedings (including efforts to
modify or vacale any automatic stay or injunction), and appeals. Borrower also
will pay any court costs, in addition to all other sums provided by law.

JURY WAIVER. LENDER AND BORROWER HEREBY WALVE THE RIGHT TO ANY JURY TRIAL IN ANY
ACTION, PROCEEDING, OR COUNTERCLAIM BROUGHT BY EITHER LENDER OR BORROWER AGAINST
THE OTHER.

GOVERNING LAW. THIS NOTE WILL BE GOVERNED BY, CONSTRUED AND ENFORCED IN
ACCORDANCE WITH FEDERAL LAW AND THE LAWS OF THE STATE OF CALIFORNIA. THIS NOTE
HAS BEEN ACCEPTED BY LENDER IN THE STATE OF CALIFORNIA.

CHOICE OF VENUE. If there is a lawsuit, Borrower agrees upon Lender's request to
submit to the jurisdiction of the courts of any County, State of California.

RIGHT OF SETOFF. To the extent permitted by applicable law, Lender reserves a
right of setoff in all Borrower's accounts with Lender (whether checking,
savings, or some other account). This includes all accounts Borrower holds
jointly with someone else and all accounts Borrower may open in the future.
However, this does not include any IRA or Keogh accounts, or any trust
accounts for which setoff would be prohibited by law. Borrower authorizes
Lender, to the extent permitted by applicable law, to charge or setoff all sums
owing on the indebtedness against any and all such accounts.

LINE OF CREDIT. This Note evidences a revolving line of credit. Advances under
this Note, as well as directions or payment from Borrower's accounts, may be
requested orally or in writing by Borrower or by an authorized person. Lender
may, but need not, require that all oral requests be confirmed in writing.
Borrower agrees to be liable for all sums either: (A) advanced in accordance
with the instructions of an authorized person or (B) credited to any of
Borrower's accounts with Lender. The unpaid principal balance owing on this Note
at any time may be evidenced by endorsements on this Note or by Lender's
internal records, including daily computer print-outs. Lender will have no
obligation to advance funds under this note if: (A) Borrower or any guarantor is
in default under the terms of this Note or any agreement that Borrower or any
guarantor has with Lender, including any agreement made in connection with the
signing of this Note; (B) Borrower or any guarantor ceases doing business or is
insolvent; (C) any guarantor seeks, claims or otherwise attempts to limit,
modify or revoke such guarantor's guarantee of this Note or any other loan with
Lender; or (D) Borrower has applied funds provided pursuant to this Note for
purposes other than those authorized by Lender.

ARBITRATION. (a) This paragraph concerns the resolution of any controversies or
claims between the parties, whether arising in contract, tort or by statute,
including but not limited to controversies or claims that arise out of or relate
to: (i) this agreement (including any renewals, extensions or modifications); or
(ii) any document related to this agreement; (collectively a "Claim").

(b) At the request of any party to this agreement, any Claim shall be resolved
by binding arbitration in accordance with the Federal Arbitration Act (Title 9,
U. S. Code) (the "Act"). The Act will apply even though this agreement provides
that it is governed by the law of a specified state.

(c) Arbitration proceedings will be determined in accordance with the Act, the
applicable rules and procedures for the arbitration of disputes of JAMS or any
successor thereof ("JAMS"), and the terms of this paragraph. In the event of any
inconsistency, the terms of this paragraph shall control.

(d) The arbitration shall be administered by JAMS and conducted, unless
otherwise required by law, in any U. S. state where real or tangible personal
property collateral for this credit is located or if there is no such
collateral, in the state specified in the governing law section of this
agreement. All Claims stall be determined by one arbitrator; however, if Claims
exceed $5,000,000, upon the request of any party, the Claims shall be decided by
three arbitrators. All arbitration headings shall commence within 90 days of the
demand for arbitration and close within 90 days of commencement and the award of
the arbitrator(s) shall be issued within 30 days of the close of the hearing.
However, the arbitrator(s), upon a showing of good cause, may extend the
commencement of the hearing for up to an additional 60 days. The arbitrator(s)
shall provide a concise written statement of reasons for the award. The
arbitration award may be submitted to any court having jurisdiction to be
confirmed and enforced.

(e) The arbitraton(s) will have the authority to decide whether any Claim is
barred by the statute of limitations and. if so, to dismiss the arbitration on
that basis. For purposes of the application of the statute of limitations, the
service on JAMS under applicable JAMS rules of a notice of Claim is the
equivalent of the filing of a lawsuit. Any dispute concerning this arbitration
provision or whether a Claim is arbitratable shall be determined by the
arbitrator(s). The arbitrator(s) shall have the power to award legal fees
pursuant to the terms of this agreement.

(f) This paragraph does not limit the right of any party to: (i) exercise
self-help remedies, such as but not limited to, setoff; (ii) initiale judicial
or nonjudicial foreclosure against any real or personal property collateral;
(iii) exercise any judicial or power of sale rights, or (iv) act in a court of
law to obtain an interim remedy, such as but not limited to, injunctive relief,
writ of possession or appointment of a receiver, or additional or supplementary
remedies.

(g) The filing of a court action is not intended to constitute a waiver of the
right of any party, including the suing party, thereafter to require submittal
of the Claim to arbitraton

(h) The procedure described above will not apply it the Claim, at the time of
the proposed submission to arbitration, arises from or relates to an obligation
to the Lender secured by real property located in California. In this case, all
of the parties to this agreement must consent to submission of the Claim to
arbitration. If both parties do not consent to arbitration, the Claim will be
resolved as follows: The parties will designate a referee (or a panel of
referees) selected under the auspices of JAMS in the same manner as arbitrators
are selected in JAMS administered proceedings. The designated referee(s) will be
appointed by a court as provided in California Code of Civil Procedure Section
638 and the following related sections. The referee (or presiding referee of the
panel) will be an active attorney or a retired judge. The award that results
from the decision of the referee(s) will be entered as a judgment in the court
that appointed the referee, in accordance with the provisions of California Code
of Civil Procedure Sections 644 and 645.

ADDITIONAL DEFAULTS.

Each of the Following shall constitute an event of default ("Event of Default")
under this Note:

EVENT OF DEFAULT UNDER RELATED DOCUMENTS. A default or event of default occurs
under the terms of any promissory note, guaranty, pledge agreement, security
agreement or other agreement or instrument executed by Borrower or any
guarantor, pledgor, accommodation party or other obligor in connection with or
relating to this Note.

JUDGMENT. The entry of a judgment against any Borrower or guarantor, pledgor,
accommodation party or other obligor which Lender deems to be of a material
nature, in Lender's sole discretion.

DEFAULT BY AFFILIATES. Any affiliate of Borrower defaults under any loan,
extension of credit, security agreement, purchase or sales agreement, or any
other agreement, in favor of Lender or any other creditor.
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                                 PROMISSORY NOTE
                                   (CONTINUED)                            PAGE 3

ADVERSE GOVERNMENT ACTION. Any governmental authority (including, without
limitation, any nation, state or other political subdivision thereof, any
central bank, and any entity exercising executive, legislative, judicial,
regulatory or administrative functions, and any corporation or other entity
owned or controlled by any of the foregoing) takes or institutes action, which,
in the opinion of Lender, will adversely affect Borrower's financial condition
or ability to pay or perform Borrower's obligations under this Note or any
instrument or agreement required under, or executed in connection with, this
Note.

SALE OF NOTE ASSIGNMENT. Lender may sell or offer to sell this Note, together
with any and all documents guaranteeing, securing or executed in connection with
this Note, to one or more assignees without notice to or consent of Borrower.
Lender is hereby authorized to share any information it has pertaining to the
loan evidenced by this Note, including without limitation credit information on
the undersigned, any of its principals, or any guarantors of this Note, to any
such assignee or prospective assignee.

COUNTERPART SIGNATURES. This Note may be executed in any number of counterparts,
each of which when so executed shall be deemed to be an original and all of
which taken together shall constitute one and the same agreement.

PRE BILLING. If the Borrower and Lender elect to use pre-billing calculation,
for each payment date (the "Due Date") the amount of each payment debit will be
determined as follows: On the "Billing Date" Lender will prepare and mail to
Borrower an invoice of the amounts that will be due on that Due Date ("Billed
Amount"). (The "Billing Date" will be a date that is a specified number of
calendar days prior to the Due Date, which number of days will be mutually
agreed from time to time by Lender and Borrower.) The calculation of the Billed
Amount will be made on the assumption that no new extensions of credit or
payments will be made between the Billing Date and the Due Date, and that there
will be no changes in the applicable interest rate. On the Due Date Lender will
debit the Designated Account for the Billed Amount, regardless of the actual
amount due on that date ("Accrued Amount"). If the Due Date does not fail on a
Business Day, Lender shall debit the Designated Account on the first Business
Day following the Due Date. For purposes of this Agreement, "Business Day" means
a day other than Saturday, Sunday or other day on which commercial banks are
authorized to close or are in fact closed in the state where the Lender's
lending office is located. If the Billed Amount debited to the Designated
Account differs from the Accrued Amount, the difference will be treated as
follows: If the Billed Amount is less than the Accrued Amount, the Billed Amount
for the following Due Date will be increased by the amount of the underpayment.
Borrower will not be in default by reason of any such underpayment. If the
Billed Amount is more than the Accrued Amount, the Billed Amount for the
following Due Date will be decreased by the amount of the overpayment.
Regardless of any such difference, interest will continue to accrue based on the
actual amount of principal outstanding without compounding. Lender will not pay
interest on any overpayment.

AUTOMATIC PAYMENTS. Borrower hereby authorizes Lender automatically to deduct
from Borrower's account numbered 14630-01929 the amount of any loan payment. If
the funds in the account are insufficient to cover any payment, Lender shall not
be obligated to advance funds to cover the payment. At any time and for any
reason, Borrower or Lender may voluntarily terminate Automatic Payments.

TERMINATION OF AUTOMATIC PAYMENTS. In the event that Borrower terminates the
Automatic Payment arrangement with Lender, Borrower agrees that the interest
rate under the Note will increase, at the discretion of the Lender, by one-half
percentage point (0.50%) per annum over the rate of interest stated in the Note,
and the amount of each interest installment will be increased accordingly. The
effective rate of interest under the Note shall not in any event exceed the
maximum rate permitted by law.

ADDITIONAL INTEREST AFTER DEFAULT. Upon any Event of Default under this Note,
Lender, at its option, may, if permitted under applicable law, increase the
interest rate on this Note to the interest rate specified in the paragraph above
entitled "Interest After Default".

CLOSING FEE. Borrower agrees to pay to Lender a loan fee in the amount of
$1,375.00. This fee is due at closing.

SUCCESSOR INTERESTS. The terms of this Note shall be binding upon Borrower, and
upon Borrower's heirs, personal representatives, successors and assigns, and
shall inure to the benefit of Lender and its successors and assigns.

GENERAL PROVISIONS. Lender may delay or forgo enforcing any of its rights or
remedies under this Note without losing them. Each Borrower understands and
agrees that, with or without notice to Borrower, Lender may with respect to any
other Borrower (a) make one or more additional secured or unsecured loans or
otherwise extend additional credit; (b) alter, compromise, renew, extend,
accelerate, or otherwise change one or more times the time for payment or other
terms any indebtedness, including increases and decreases of the rate of
interest on the indebtedness; (c) exchange, enforce, waive, subordinate, fail or
decide not to perfect, and release any security, with or without the
substitution of new collateral; (d) apply such security and direct the order or
manner of sale thereof, including without limitation, any non-judicial sale
permitted by the terms of the controlling security agreements, as Lender in its
discretion may determine; (e) release, substitute, agree not to sue, or deal
with any one or more of Borrower's sureties, endorsers, or other guarantors on
any terms or in any manner Lender may choose; and (f) determine how, when and
what application of payments and credits shall be made on any other indebtedness
owing by such other Borrower. Borrower and any other person who signs,
guarantees or endorses this Note, to the extent allowed by law, walve any
applicable statute of limitations, presentment, demand for payment, and notice
of dishonor. Upon any change in the terms of this Note, and unless otherwise
expressly stated in writing, no party who signs this Note, whether as maker,
guarantor, accommodation maker or endorser, shall be released from liability.
All such parties agree that Lender may renew or extend (repeatedly and for any
length of time) this loan or release any party or guarantor or collateral; or
impair, fail to realize upon or perfect Lender's security interest in the
collateral; and take any other action deemed necessary by Lender without the
consent of or notice to anyone. All such parties also agree that Lender may
modify this loan without the consent of or notice to anyone other than the party
with whom the modification is made. The obligations under this Note are joint
and several.
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                                PROMISSORY NOTE
                                  (CONTINUED)                             PAGE 4

PRIOR TO SIGNING THIS NOTE, EACH BORROWER READ AND UNDERSTOOD ALL THE PROVISIONS
OF THIS NOTE, INCLUDING THE VARIABLE INTEREST RATE PROVISIONS. EACH BORROWER
AGREES TO THE TERMS OF THE NOTE.

BORROWER ACKNOWLEDGES RECEIPT OF A COMPLETED COPY OF THIS PROMISSORY NOTE.

BORROWER:

TRIO-TECH INTERNATIONAL

By: /s/ A. Charles Wilson                       By: /s/ Siew Wai Yong
   -------------------------------------           -----------------------------
   A. Charles Wilson, Chairman of the              Siew Wai Yong, President/CEO
   Board of Trio-Tech International                of Trio-Tech International


KTS INCORPORATED

By: /s/ A. Charles Wilson                       By: /s/ Siew Wai Yong
   -------------------------------------           -----------------------------
   A. Charles Wilson, Chairman of the              Siew Wai Yong, President/CEO
   Board of KTS Incorporated                       of KTS Incorporated

                                   [ILLEGIBLE]