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                                                                   EXHIBIT 10.16

                                 PROMISSORY NOTE


$12,997,444                                                        April 1, 1997
                                                             Anaheim, California


         FOR VALUE RECEIVED, ATL Products, Inc., a Delaware corporation (the
"Borrower"), promises to pay to the order of Odetics, Inc., a Delaware
corporation (the "Lender"), at Anaheim, California, or at such other place as
the holder of this Note may from time to time designate in writing, the
principal amount of $12,997,444.00 dollars, with interest on the principal
amount from the date of disbursement of the principal amount at the rate per
annum set forth in this Note, to be paid as set forth in this Note.

         The principal amount of this Note shall bear interest at the rate per
annum equal to Lender's cost of borrowing from the lesser of either of Lender's
primary banks, or Lender's principal bank, as the case may be during the term of
the Note, but shall not exceed the maximum rate of interest permitted by
applicable law.

         The Borrower shall pay the principal amount of this Note and interest
in sixteen (16) equal quarterly installments at the end of each calendar quarter
commencing June 30, 1997 and continuing until all principal and interest have
been fully paid. Each payment of principal shall be accompanied by a payment
equal to all interest accrued on the outstanding principal amount of the Note.

         The Borrower shall have the right to prepay the principal sum of this
Note, or any part thereof or interest thereon, at any time without penalty or
prepayment charge.

         Both principal and interest shall be paid by Borrower in lawful money
of the United States of America in cash or in the form of a cashier's or
certified check.

         If the Borrower shall default in the timely making of any payment of
principal and/or interest due hereunder and if the same remains unpaid for
fifteen (15) days following receipt by Borrower of written notice of such
default the Lender may declare the entire remaining indebtedness owing
hereunder, including any accrued interest, to become immediately due and
payable.

         Notwithstanding anything to the contrary in this Note, the total
liability of the Borrower for payments in the nature of interest shall not
exceed the limits applicable to this Note, if any, imposed by the usury laws, if
any, of the United States of America or the State of California. If any payment
in the nature of interest made by the Borrower or received by the holder of this
Note is determined to be in excess of any limit applicable to this Note imposed
by such usury laws, then the amount of such excess shall constitute and be
considered a payment of principal, not interest, and such amount shall be
applied to reduce the principal sum so that the total liability of the Borrower
for payments in the nature of interest does not exceed the


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applicable limits, if any, imposed by such usury laws. In the event and to the
extent such excess amount of interest exceeds the outstanding unpaid principal
balance hereunder, any such excess amount shall be immediately returned to
Borrower by Lender.

         No delay or omission on the part of the Lender hereof in exercising any
right hereunder shall operate as a waiver of such right or of any other right
under this Note.

         Neither this Note nor any term hereof may be waived, amended,
discharged, modified, changed, or terminated orally, nor shall any waiver of any
provision hereof be effective except by an instrument in writing signed by
Borrower and the Lender thereof.

         Whenever used herein, the words "Borrower" and "Lender" shall be deemed
to include their respective heirs, personal representatives, successors and
assigns.

         All notices to be given under this Note shall be deemed served upon
receipt by the addressee or, if mailed, upon the expiration of seventy-two (72)
hours after deposit in the United States Postal Service, certified mail, postage
prepaid, addressed to the address of Borrower or Lender as hereinafter set
forth:

         Borrower's Address:                 2801 Kelvin Avenue
                                             Irvine, California 92715
                                             Attention:  Chief Executive Officer

         Lender's Address:                   1515 South Manchester Avenue
                                             Anaheim, California 92802-2907
                                             Attention:  Chief Executive Officer

         This Note may from time to time be extended or renewed, with or without
notice to Borrower or any guarantor hereon and any related right may be waived,
exchanged, surrendered or otherwise dealt with, all without affecting the
liability of Borrower or any guarantor hereon.

         There are no oral agreements between the Lender and the Borrower
relating to this Note. If any provision of this Note is held to be invalid or
unenforceable, it shall not affect the validity and enforceability of the other
provisions of this Note. This Note has been executed and delivered in the State
of California and is to be governed by and construed according to the laws
thereof.


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         IN WITNESS WHEREOF, the Borrower has executed this Note as of the date
first hereinabove written.


                                               ATL Products, Inc.


                                               By:  /s/ Kevin C. Daly
                                                    ---------------------------
                                                    Kevin C. Daly, Ph.D.
                                                    Chief Executive Officer


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