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                                                                    Exhibit 10.7


                                 PROMISSORY NOTE

$5,128,500.00                                                  Las Vegas, Nevada
                                                               February 28, 2001

                  FOR VALUE RECEIVED, the undersigned hereby promises to pay to
the order of Elektryon, a Nevada corporation (the "Company"), or to the order of
any subsequent holder of this Note (the Company or any such subsequent holder is
referred to herein as the "Holder"), at 6565 Spencer Street, Suite 206, Las
Vegas, Nevada, or such other place as may be designated by the Holder, on
February 28, 2006, the principal sum of FIVE MILLION ONE HUNDRED TWENTY-EIGHT
THOUSAND FIVE HUNDRED DOLLARS ($5,128,500.00) in lawful money of the United
States, subject to the mandatory prepayment provisions of this Note and to
acceleration in whole or in part as provided in this Note, together with
interest as specified herein from the date of this Note.

                  The outstanding principal amount of this Note shall bear
interest from the date hereof until the principal amount of this Note shall
become due and payable (whether by passage of time, acceleration or otherwise)
at the annual rate of 6%, and interest shall be payable in cash when the
principal amount of this Note shall become due and payable (whether by passage
of time, acceleration or otherwise) and as otherwise provided in this Note. If
at any time until payment in full of all obligations due hereunder, the interest
rate provided in this Note exceeds the highest rate of interest permissible
under any law which a court of competent jurisdiction shall, in a final
determination, deem applicable to this Note, then in such event and so long as
such rate would be so exceeded, the rate of interest payable hereunder shall be
equal to such maximum legal rate. Upon the occurrence of an Event of Default (as
defined below) and the acceleration of the outstanding principal amount under
this Note, all accrued and unpaid interest thereon shall become immediately due
and payable in immediately available funds, and all interest accruing until such
Event of Default is cured or all amounts due hereunder shall be paid, shall be
payable in immediately available funds. Commencing upon the occurrence of an
Event of Default, the undersigned shall pay interest on overdue principal and
overdue interest at a default rate per annum equal to the greater of (x) the
rate per annum announced publicly by The Chase Manhattan Bank in New York, New
York (or any successor thereof) as The Chase Manhattan Bank's (or such
successor's) base or "prime" rate in effect at the time of such Event of
Default, plus 500 basis points, and (y) 10% per annum. Interest shall be
computed on the basis of a 360-day year consisting of twelve 30-day months.

                  The undersigned shall have the right at any time and from time
to time after August 28, 2001 to prepay (without premium or penalty) all or any
portion of the outstanding principal balance due under this Note (together with
accrued interest on the principal amount so prepaid). Any partial prepayments
shall be applied first to accrued and unpaid interest and then to principal.

                  If the undersigned elects or is required to sell, transfer,
dispose or surrender, or shall sell, transfer, dispose or surrender, from time
to time, any or all Pledged Securities (as defined in the Pledge Agreement of
even date herewith (the "Pledge Agreement") among the undersigned and the
Company) the undersigned shall, as a condition to and contemporaneous with the
consummation of any such sale, transfer, disposition or surrender, apply all of
the proceeds of such sale, transfer, disposition or surrender (net only of
commissions and other transaction expenses not exceeding in
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the aggregate 10% of the gross proceeds of such sale, transfer, disposition or
surrender (without duplication of the commissions and other transaction expenses
referred to in Section 5(a) of the Separation Agreement)) to prepay all accrued
and unpaid interest on this Note and the then outstanding principal amount of
this Note, in that order; provided that if the undersigned shall receive in any
such sale, transfer, disposition or surrender any securities, evidences of
indebtedness or other property (other than cash), the same shall be promptly
delivered to the Company and held as Collateral (as defined in the Pledge
Agreement) under the Pledge Agreement and the same shall not be applied to
prepay this Note (unless done so in accordance with the Pledge Agreement), and
no commissions or other transaction expenses shall be deducted by the
undersigned or any other person or entity from the gross proceeds of such sale,
transfer, disposition or surrender. Any prepayment made by the undersigned
pursuant to this paragraph shall be without penalty or premium. Nothing herein
is intended as a consent to any such sale, transfer, disposition or surrender,
which in each case may only be made in accordance with the Pledge Agreement, the
Separation Agreement (as defined in the Pledge Agreement), the Release, dated as
of the date hereof, among the Company, the undersigned and the other party
identified therein, and the Voting Agreement (as defined in the Pledge
Agreement) (all such agreements are referred to herein as the "Concurrent
Agreements"). This Note is issued pursuant to the Separation Agreement.

                  The occurrence of any one or more of the following events
shall constitute an event of default (each an "Event of Default"): (1) the
nonpayment when the same becomes due, whether pursuant to the mandatory
prepayment provisions of this Note, by acceleration or otherwise, of principal
of, or interest on, this Note; (2) the default or breach in any material respect
by the undersigned in the payment or performance of any obligation, covenant,
agreement, term or condition of any of the Concurrent Agreements which is not
remedied within 30 days following notice by the Company (or any subsequent
Holder) to the undersigned specifying any such default or breach; (3) the filing
by or against the undersigned of a request or petition for liquidation,
reorganization, arrangement, adjustment of debts, adjudication as a bankrupt,
relief as a debtor or other relief under the bankruptcy, insolvency or similar
laws of the United States or any state or territory thereof or any foreign
jurisdiction, now or hereafter in effect; (4) the making of any general
assignment by the undersigned for the benefit of creditors; (5) the appointment
of a receiver or trustee for the undersigned or for any assets of the
undersigned, including, without limitation, the appointment of, or taking
possession by, a "custodian" (as defined in the United States Bankruptcy Code);
(6) the nonpayment by the undersigned when due, whether by acceleration, demand
or otherwise (within any applicable period of grace in any instrument evidencing
any such indebtedness), of any indebtedness for borrowed money owing to any
party other than the Company (or any subsequent Holder), or the occurrence of
any event which could result in acceleration of the time for payment of any such
indebtedness; provided the outstanding amount of such indebtedness exceeds
$250,000 in the aggregate,and such nonpayment continues for a period of 60 days
from the first day (after the expiration of any applicable period of grace) on
which such indebtedness became due and payable; (7) if any statement,
representation or warranty made by or on behalf of the undersigned to the
Company in any of the Concurrent Agreements shall not be true and correct in any
material respect at the time when made; or (8) the death or legal incapacity of
the undersigned. Upon the occurrence of an Event of Default, the Company or any
other Holder may declare by notice to the undersigned all of the Obligations (as
defined below) under this Note to be immediately due


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and payable without any other election or action on the part of the Company or
any other Holder, without any presentment or demand, or further notice of any
kind, all of which are hereby expressly waived by the undersigned.
Notwithstanding anything to the contrary contained herein, if an Event of
Default described in the foregoing clauses (3), (4), (5) or (8) shall occur, all
amounts outstanding under this Note shall become immediately due and payable
without any declaration, notice or other act on the part of the Holder or any
other party. When an Event of Default described in the foregoing clauses (3),
(4), (5) or (6) shall occur, the undersigned hereby agrees to give written
notice within seven Business Days of such Event of Default to the Holder.

                  No failure by the Holder to exercise, and no delay in
exercising, any right or remedy hereunder or under any other agreement or
instrument shall operate as a waiver thereof, nor shall any single or partial
exercise by such Holder of any right or remedy hereunder or under any other
agreement or instrument preclude any other or further exercise thereof or the
exercise of any other right or remedy. The rights and remedies of the Holder as
herein specified are cumulative and not exclusive of any other rights or
remedies which such Holder may otherwise have, including, without limitation,
any rights or remedies under any Concurrent Agreement, including the Pledge
Agreement. In addition to any rights and remedies afforded to the Holder under
this Note and any Concurrent Agreement, the Holder shall, upon the occurrence of
an Event of Default, be entitled to exercise any and all rights and remedies
available to it under applicable law.

                  No modification, rescission, waiver, forbearance, release or
amendment of any provision of this Note shall be made, except by a written
agreement duly executed by the undersigned and the Holder hereof.

                  The undersigned hereby waives diligence, demand, protest and
notice of any kind, and assents to extensions of the time of payment, release,
surrender or substitution of security, or forbearance or other indulgence,
without notice.

                  THIS NOTE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE
WITH THE LAWS OF THE STATE OF NEVADA (WITHOUT GIVING EFFECT TO THE CONFLICTS OF
LAWS PRINCIPLES THEREOF). In addition, the undersigned (a) consents to submit
himself to the non-exclusive personal jurisdiction of any federal court located
in the State of Nevada or any Nevada state court in the event any dispute arises
out of this Note or any of the transactions contemplated by this Note, and (b)
agrees that he will not attempt to deny or defeat such non-exclusive personal
jurisdiction by motion or other request for leave from any such court.

                  The undersigned agrees to pay all costs and expenses incurred
by the Holder in enforcing this Note, including, without limitation, reasonable
attorneys' fees, to the extent permitted by law (which obligation shall be
secured by the Pledge Agreement).

                  Payment of this Note (including the principal amount hereof,
interest hereon and costs and expenses arising hereunder (collectively, the
"Obligations")) is secured by Collateral (as defined in the Pledge Agreement)
granted by the undersigned to the Company pursuant to the Pledge


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Agreement and such other documents as may have been or may hereafter be executed
in favor of the Company by the undersigned.

                  The Obligations of the undersigned under this Note are
non-recourse to him personally other than with respect to the Collateral
(against which recourse may be had) and the Holder agrees to look only to the
Collateral pledged under the Pledge Agreement for recovery and/or satisfaction
of the Obligations; provided, that nothing contained in this sentence shall be
construed, interpreted or deemed in any fashion to release or impair the
Obligations under this Note or the Lien (as defined in the Pledge Agreement)
upon the Collateral created by the Pledge Agreement or to preclude the
application of the Collateral to the payment or satisfaction of the Obligations.

                  The Company (or any other Holder) shall have the right to
withhold and set-off against any amount due hereunder any amount payable by the
Company (or such Holder) to the undersigned.

                  If any provision of this Note is held to be invalid or
unenforceable by any court of competent jurisdiction, the other provisions of
this Note will remain in full force and effect. Any provision of this Note held
to be invalid or unenforceable only in part or degree will remain in full force
and effect to the extent not held to be invalid or unenforceable.

                  This Note shall be binding upon the undersigned and his
successors and assigns (however, the undersigned may not assign or delegate his
obligations hereunder without the consent of the Holder) and shall inure to the
benefit of the Holder and its successors and assigns (and each reference to the
Holder or the Company shall be deemed to include their respective successors and
assigns). This Note may be assigned or transferred by the Company or any other
Holder without the consent of the undersigned.

                                    /s/ Phil C. Meisinger
                                    ---------------------------------
                                    Phil C. Meisinger