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                                                                   EXHIBIT 10.16

                     DEVELOPMENTAL LICENSING AGREEMENT FOR A
                              DIELECTRIC RESONATOR

         This agreement (hereinafter "AGREEMENT") is entered into by and between
NATIONAL SCIENTIFIC CORPORATION (hereinafter "NSC"), a Texas corporation having
headquarters at 4455 East Camelback Road, Suite E-160, Phoenix, Arizona, USA
85018, and TEMEX, a subsidiary of TEKELEC Group, (hereinafter "TEMEX"), a French
Corporation having a worldwide headquarters at 29, avenue de la Baltique, 91 953
Les ULIS Cedex, FRANCE, and a United States headquarters at 3030 Deer Valley
Road, Phoenix, AZ 85027.

RECITALS

         WHEREAS, NSC owns certain rights, title, and interest in and to various
patents and patent applications concerning the subject matter of dielectric
resonators, as follows:

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------------------------
LICENSED TECHNOLOGY
--------------------------------------------------------------------------------------------------------------------
Patent or          Title                                       Inventor                 Date of Issue        Country
Application
number
--------------------------------------------------------------------------------------------------------------------
<S>                <C>                                         <C>                      <C>                  <C>
6,169,467          Dielectric Resonator Comprising A           El-Badawy Amien          2 January 2001       US
                   Dielectric Resonator Disk Having A Hole     El-Sharawy
--------------------------------------------------------------------------------------------------------------------
99925897.3         Dielectric Resonator                        El-Badawy Amien          (pending)            EP
                                                               El-Sharawy
--------------------------------------------------------------------------------------------------------------------
2000-555315        Dielectric Resonator                        El-Badawy Amien          (pending)            JP
                                                               El-Sharawy
--------------------------------------------------------------------------------------------------------------------
</TABLE>

(hereinafter "LICENSED TECHNOLOGY") and is willing to offer a limited
manufacturing license of the LICENSED TECHNOLOGY to TEMEX for the purpose of
producing samples for the use of potential customer evaluation and proving
technology claims of the LICENSED TECHNOLOGY for a $10.00 licensing fee; and

         WHEREAS, TEMEX is engaged in manufacturing and selling a variety of
components including dielectric resonators and wishes to investigate the
technical and commercial claims of such a license under the terms and conditions
of this AGREEMENT;

WHEREAS, TEMEX agrees to share all test and experimental results obtained from
the LICENSED TECHNOLOGY;

WHEREAS, both companies agree to mutually negotiate, subject to a successful
evaluation a mutually beneficial licensing agreement on NSC's Mode Dielectric
Resonator technology on or before December 31, 2001;

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         NOW, THEREFORE, in consideration of the following mutual covenants and
obligations, NSC and TEMEX agree as follows:

                             ARTICLE 1 - DEFINITIONS

         When used in this AGREEMENT, each of the following terms shall have the
meaning indicated:

         1.1 "EFFECTIVE DATE" shall mean the date of execution of this AGREEMENT
by both parties.

         1.2 "LICENSED PRODUCT(S)" shall mean any and all products or portions
thereof, based upon, using, or incorporating, in whole or in part, the
technology claimed in the LICENSED TECHNOLOGY.

         1.3 An "AFFILIATE COMPANY" shall mean (1) any corporation, company, or
other legal entity that controls a majority of ownership in, or for which a
majority of ownership is controlled by, the company; (2) any corporation,
company, or other legal entity that controls a majority of ownership in, or for
which a majority of ownership is controlled by, the legal entities identified by
item (1) herein; (3) any corporation, company, or other legal entity that
controls a majority of ownership in, or for which a majority of ownership is
controlled by, the legal entities identified in items (1) or (2) herein; and so
on.

                                    ARTICLE 2
                   LIMITATIONS ON USE OF DATA AND INFORMATION

     2.1 The parties anticipate that under this Agreement it may be necessary
for either party to transfer to the other information of a proprietary nature.
Proprietary information shall be clearly identified by the disclosing party at
the time of disclosure by (i) appropriate stamp or markings on the document
exchanged; or (ii) written notice, with attached listings of all material,
copies of all documents, and complete summaries of all oral disclosures (under
prior assertion of the proprietary nature of the same) to which each notice
relates, delivered within two (2) weeks of the disclosure to the other party.

     2.2 Each of the parties agrees that it will use the same reasonable efforts
to protect such information as are used to protect its own proprietary
information. Disclosures of such information shall be restricted to those
individuals who are directly participating in the proposal


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     2.3 Neither party shall make any reproduction, disclosure, or use of such
proprietary information except as follows:

         2.3.1 Such information furnished by the NSC may be used, reproduced
and/or disclosed by Temex in performing its obligations under this Agreement.

         2.3.2 Such information furnished by Temex may be used, reproduced
and/or disclosed by the NSC in performing its obligations under this Agreement.

         2.3.3 Such information may be used, reproduced and/or disclosed for
other purposes only in accordance with prior written authorization received from
the disclosing party.

     2.4 The limitations on reproduction, disclosure, or use of proprietary
information shall not apply to, and neither party shall be liable for
reproduction, disclosure, or use of proprietary information with respect to
which any of the following conditions exist:

         2.4.1 If, prior to the receipt thereof under this Agreement, it has
been developed or learned independently by the party receiving it, or has been
lawfully received from other sources, provided such other source did not receive
it due to a breach of this Agreement or any other agreement.

         2.4.2 If, subsequent to the receipt thereof under this Agreement, (i)
it is published by the party furnishing it or is disclosed, by the party
furnishing it to others, without restriction; or (ii) it has been lawfully
obtained, by the party receiving it, from other sources, provided such other
source did not receive it due to a breach of this or any other agreement; or
(iii) such information otherwise comes within the public knowledge or becomes
generally known to the public;

         2.4.3 If any part of the proprietary information has been or hereafter
shall be disclosed in a United States patent issued to the party furnishing the
proprietary information hereunder, the limitations on such proprietary
information as is disclosed in the patent shall be only that afforded by the
United States Patent Laws after the issuance of said patent.

         2.4.5 If any part of the proprietary information is required by law to
be disclosed, the party required to make disclosure shall notify the other to
allow that party to assert whatever exclusions or exemptions may be available to
it under such law or regulation.

         2.5 Neither the execution and delivery of this Agreement, nor the
furnishing of any proprietary information by either party shall be construed as
granting to the other party either expressly, by implication, estoppels, or
otherwise, any license under any invention or patent now or hereafter owned or
controlled by the party furnishing the same.

         2.6 Notwithstanding the expiration of the other portions of this
Agreement, the obligations and provisions of this Article 2 shall continue for a
period of three (3) years from the date of this Agreement, however, any
resulting contract shall take precedence.


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                         ARTICLE 3. RIGHTS IN INVENTIONS

Inventions conceived or first reduced to practice during the course of work
under the Contract contemplated by this Agreement shall remain the property of
the inventing party. In the event of joint inventions, the parties shall
establish their respective rights by negotiations between them.

                              ARTICLE 4. PUBLICITY

No publicity or advertising regarding any proposal or contract under the Program
or relating to this Agreement shall be released by the either party without the
prior written approval of the other, except for press releases that in general
terms overview the nature and existence of this Agreement. The drafting party
will provide such general releases to the other party in advance of their
release.

                             ARTICLE 5. TERMINATION

This Agreement, which is effective upon the date of its execution by the last of
the signatory parties hereto, shall automatically expire, be deemed terminated,
with each party relieved of any obligations hereunder except as set forth in
Article 2, effective upon the date of the happening or occurrence of any one of
the following events or conditions, whichever shall first occur:

         5.1 Mutual agreement of the parties to terminate the Agreement.

         5.2 The expiration of a six month period commencing on the effective
date of this Agreement unless such period is extended by mutual agreement of the
parties. Or,

         5.3 Written notice from one party to the other of the intent to
terminate this Agreement without cause, given that such written notice is
provided at least 30 days before the termination date in the letter of notice.

                               ARTICLE 6. GENERAL

         6.1 This Agreement pertains only to the proposal relating to the
limited development license and to no other joint or separate effort undertaken
by NSC or Temex. The parties hereto shall be deemed to be independent
contractors and the employees of one party shall not be deemed to be employees
of the other. This Agreement does not create a partnership between the parties.

         6.2 This Agreement may not be assigned or otherwise transferred by
either party, in whole or in part, without the express prior written consent of
the other party.

         6.3 This Agreement shall not preclude either party from bidding or
contracting independently from the other on any industry program which may
develop or arise in the general area of business related to this Agreement or in
any other area.

         6.4 This Agreement contains the entire agreement of the parties and
cancels and supersedes any previous understanding or agreement related to the
Program, whether written or oral. All changes or modifications to this Agreement
must first be agreed to in writing between the parties.

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         6.5 Each party to this Agreement will bear its respective costs, risks,
and liabilities incurred by it as a result of its obligations and efforts under
this Agreement. Therefore, neither NSC nor Temex shall have any right to any
reimbursement, payment, or compensation of any kind from each other during the
period prior to the award and execution of any resulting Licensing Agreement.

         6.6 In the event a full licensee is not awarded as a result of a
proposal each party will, at the request of the other party, return all
materials such as, but not limited to, those that are written, printed, drawn,
or reproduced, to the originating party.

         6.7 Severability. All agreements and covenants contained herein are
severable, and in the event any of them shall be held to be invalid by any court
of competent jurisdiction, this Agreement shall be interpreted as if such
invalid agreements and covenants were not contained herein.

         6.8 Choice of Law. It is the intention of the parties that this
Agreement and its performance and all suits and special proceedings hereunder be
construed in accordance with and under and pursuant to the laws of the state of
Arizona and that in any action, special proceeding or other proceedings that may
be brought, arising out of, in connection with, or by reason of this Agreement,
the laws of the state of Arizona shall be applicable and shall govern to the
exclusion of the law of any other forum, without regard to the jurisdiction in
which any action or special proceeding may be instituted.

         6.9 Waiver. The waiver by either party of any breach or violation of
any provision of this Agreement shall not operate or be construed as a waiver of
any subsequent breach or violation hereof.

         6.10 Entire Agreement. This Agreement contains the complete agreement
concerning the arrangement between the parties. The parties acknowledge that any
statements or representations that may have been made previously by either of
them to the other are of no effect and that neither of them has relied on such
considerations in concluding this Agreement.

         6.11 Attorney Fees. Should either party bring an action or claim as a
result of a breach of this agreement, then the prevailing party in such action
shall be entitled to the award of reasonable attorney's fees and costs.

Dated this 26 day of June, 2001.

Temex:                                               National Scientific:

By:    Fredrick Petit                                By:     L.L. Ross
   ----------------------------                         -----------------------
Printed Name:   Fredrick Petit                       Printed Name:   L.L. Ross
             ------------------                                   -------------
Title:    Marketing Director                         Title:    Chairman/CEO
      -------------------------                            --------------------
Date:     June 26, 2001                              Date:     June 26, 2001
      -------------------------                            --------------------


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