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                                 PROMISSORY NOTE

$22,125.00                        Dallas, Texas                    July 2, 1996

     FOR VALUE RECEIVED, the undersigned, Joe Hardt ("Maker"), promises to 
pay to the order of AMX Corporation, a Texas corporation ("Payee"), at 11995 
Forestgate Drive, Dallas, Texas 75243 or such other place as the holder 
hereof shall designate in writing to Maker, in lawful money of the United 
States of America, the principal sum of Twenty Two Thousand One Hundred 
Twenty Five and No/100 Dollars ($22,125.00), or so much thereof as may have 
been advanced from time to time, payable in single payment of principal and 
accrued interest on July 2, 1999. Interest shall accrue on the principal 
balance outstanding hereunder at the lesser of (a) the Maximum Rate and (b) 
8.25% per annum.

All past due principal shall bear interest at the Maximum Rate.

     Maker shall have the right to prepay, at any time and from time to 
time without premium or penalty, the entire unpaid balance of this note or 
any portion thereof.

     Notwithstanding anything herein to the contrary, no provision of this 
note shall require the payment or permit the collection of interest in excess 
of the maximum rate permitted by applicable law as the same exists from day 
to day during the term hereof, including, as to Article 5069-1.04, Vernon's 
Texas Civil Statutes (and as the same may be incorporated by reference in 
other Texas Statutes), but otherwise without limitation, that rate based upon 
the "indicated rate ceiling" (the "Maximum Rate"). If interest in excess of 
the Maximum Rate is herein provided for, or shall be adjudicated to be so 
provided, in this note or otherwise in connection with this loan transaction, 
the provisions of this paragraph shall govern and prevail, and neither Maker 
nor the sureties, guarantors, successors or assigns of Maker shall be 
obligated to pay the excess amount of such interest, or any other excess sum 
paid for the use, forbearance or detention of sums loaned pursuant hereto. If 
for any reason interest in excess of the Maximum Rate shall be deemed 
charged, required or permitted or otherwise should arise, any such excess 
shall be applied as a payment and reduction of the principal of indebtedness 
evidenced by this note; and, if the principal amount hereof has been paid in 
full, any remaining excess shall forthwith be paid to Maker.

     If default be made in the payment of principal or interest under this 
note or upon the occurrence of any default under any agreement or instrument 
securing this note, the holder hereof may at its option, after five (5) days 
written notice to Maker, declare the entire principal balance and accrued 
interest owing hereon immediately due and payable, without demand or 
presentment, all of which are hereby waived, and the holder hereof shall have 
the right to foreclose or otherwise enforce all liens or security interests 
securing payment hereof, or any part hereof; and Maker, and all the 
collateral securing this note shall be subject to foreclosure under 
applicable law. Failure to exercise this option shall not constitute a waiver 
of the right to exercise the same in the event of any subsequent default.

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     If the holder hereof expends any effort in any attempt to enforce 
payment of all or any part or installment of any sum due the holder 
hereunder, or if this note is placed in the hands of an attorney for 
collection, or if it is collected through any legal proceedings, Maker agrees 
to pay all collection costs and fees incurred by the holder, including 
reasonable attorneys' fees.

     Maker and each surety, guarantor, endorser and other party ever liable 
for payment of any sums of money payable on this note, jointly and severally 
waive presentment and demand for payment, protest, notice of protest and 
nonpayment or dishonor, notice of acceleration and notice of intent to 
accelerate, diligence in collecting and grace, and consent to all extensions, 
without notice for any period or periods of time and partial payments, before 
or after maturity, without prejudice to the holder. The holder shall 
similarly have the right to deal in any way, at any time, with one or more of 
the foregoing parties with out notice to any other party and without in any 
way affecting the personal liability of any party hereunder.

     THIS NOTE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS 
OF THE STATE OF TEXAS AND THE APPLICABLE LAWS OF THE UNITED STATES OF 
AMERICA. ALL OBLIGATIONS ARISING HEREUNDER SHALL BE PERFORMABLE IN DALLAS 
COUNTY, TEXAS.

                                           MAKER:



                                           /s/ JOE HARDT
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