EXHIBIT 10.50

PROMISSORY NOTE

|Borrower: |  | Transcrypt International, Inc.
4800 NW 1st Street
Lincoln, NE 68521-9918 |  | Lender: U.S. Bank National Association
Lincoln Main
233 South 13th Street
Lincoln, NE 68508
|--------- |  | ------------------------------------------------------------------------ |  | -------------------------------------------------------------------------------------------

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Principal Amount: $10,000,000.00 Initial Rate: 7.770% Date of Note: September 30, 2000

PROMISE TO PAY.Transcrypt International, Inc. ("Borrower") promises to pay to U.S. Bank National Association ("Lender"), or order, in
lawful money of the United States of America, the principal amount of Ten Million & 00/100 Dollars ($10,000,000.00) 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
June 1, 2001. In addition, Borrower will pay regular monthly payments of accrued unpaid Interest beginning October 31, 2000, and all subsequent Interest payments are due on the last day
of each month after that. 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. Unless otherwise agreed or required by applicable law,
payments will be applied first to accrued unpaid Interest, then to principal, and any remaining amount to any unpaid collection costs and late charges.

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 One Month Certificate of Deposit (the "Index"). Rate is based on Lender's One Month Certificate of Deposit in effect as of the day of such resettling. Lender will tell Borrower the
current Index rate upon Borrower's request. Borrower understands that Lender may make loans based on other rates as well. The Interest rate change will not occur more often than each month beginning
October 1, 2000 and on the first day of each month thereafter. The Index currently is 6.520% per annum. The Interest rate to be applied to the unpaid principal balance of this Note will be at a
rate of 1.250 percentage points over the Index, resulting In an Initial rate of 7.770% per annum. 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, they will reduce the principal balance due.

DEFAULT.Borrower will be In default if any of the following happens: (a) Borrower fails to make any payment
when due. (b) Borrower breaks any promise Borrower has made to Lender, or Borrower fails to comply with or to perform when due any other term, obligation, covenant, or condition contained in
this Note or any agreement related to this Note, or In any other agreement or loan Borrower has with Lender. (c) Borrower defaults under any loan, extension of credit, security

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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 or Borrower's ability to repay this Note
or perform Borrower's obligations under this Note or any of the Related Documents. (d) Any representation or statement made or furnished to Lender by Borrower or on Borrower's behalf is false
or misleading in any material respect either now or at the time made or furnished. (e) Borrower becomes insolvent, a receiver is appointed for any part of Borrower's property, Borrower makes an
assignment for the benefit of creditors, or any proceeding is commenced either by Borrower or against Borrower under any bankruptcy or insolvency laws. (f) Any creditor tries to take any of
Borrower's property on or in which Lender has a lien or security Interest. This includes a garnishment of any of Borrower's accounts with Lender. (g) Any guarantor dies or any of the other
events described in this default section occurs with respect to any guarantor of this Note. (h) A material adverse change occurs
in Borrower's financial condition, or Lender believes the prospect of payment or performance of the indebtedness is impaired. (i) Lender in good faith deems itself insecure.

If
any default, other than a default In payment, is curable and if Borrower has not been given a notice of a breach of the same provision of this Note within the preceding twelve
(12) months, it may be cured (and no event of default will have occurred) if Borrower, after receiving written notice from Lender demanding cure of such default: (a) cures the default
within fifteen (15) days; or (b) if the cure requires more than fifteen (15) days, immediately initiates steps which Lender deems in Lenders sole discretion to be sufficient to
cure the default and thereafter continues and completes all reasonable and necessary steps sufficient to produce compliance as soon as reasonably practical.

LENDER'S RIGHTS.Upon default, Lender may declare the entire unpaid principal balance on this Note and all accrued
unpaid interest immediately due, without notice, and then Borrower will pay that amount. Upon default, including failure to pay upon final maturity, Lender, at its option, may also, if permitted under
applicable law, increase the variable interest rate on this Note to 4.250 percentage points over the Index. The interest rate will not exceed the maximum rate permitted by applicable law.
Lender may hire or pay someone else to help collect this Note if Borrower does not pay. Borrower also 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 and legal expenses for bankruptcy proceedings (including efforts to modify or vacate any
automatic stay or injunction), appeals and any anticipated post-judgment collection services. If not prohibited by applicable law, Borrower also will pay any court costs. In addition to
all other sums provided by law. This Note has been delivered to Lender and accepted by Lender in the State of Nebraska. If there is a lawsuit, Borrower agrees upon Lender's request to submit to the
jurisdiction of the courts of Lancaster County, the State of Nebraska. This Note shall be governed by and construed In accordance with the laws of the State of Nebraska.

RIGHT OF SETOFF.Borrower grants to Lender a contractual security interest in, and hereby assigns, conveys, delivers,
pledges, and transfers to Lender all Borrower's right, title and interest in and to, Borrower's accounts with Lender (whether checking, savings, or some other account), including without limitation
all accounts held jointly with someone else and all accounts Borrower may open in the future, excluding however all IRA and Keogh accounts, and all trust accounts for which the grant of a security
interest would be prohibited by law. Borrower authorizes Lender, to the extent permitted by applicable law, to charge or setoff all sums owing on this Note against any and all such accounts.

COLLATERAL.This Note is secured by FS/SA on All Business Assets and 2 U.S. Bank National Association Certificates of
Deposit.

LINE OF CREDIT.This Note evidences a revolving line of credit. Advances under this Note may be requested orally by
Borrower or by an authorized person. Lender may, but need not, require that all oral requests be confirmed in writing. All communications, instructions, or directions by telephone or otherwise to
Lender are to be directed to Lender's office shown above. The following party or parties

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are authorized to request advances under the line of credit until Lender receives from Borrower at Lender's address shown above written notice of revocation of their authority: Massoud Safavi, Scott
W. Avery, Rick D. Schmitz and David Hattey. 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 dally
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; (d) Borrower has applied funds
provided pursuant to this Note for purposes other than those authorized by Lender; or (e) Lender in good faith deems itself insecure under this Note or any other agreement between Lender and
Borrower.

PURPOSE OF LOAN.Working Capital Support.

PAYMENT OF INTEREST ACCRUED ON REPACED NOTE.All interest accrued but unpaid on Borrower's promissory note dated
August 31, 1999, payable to the order of Lender in the original principal amount of $10,000,000.00, as amended, supplemented, extended or otherwise modified shall be due and payable in full on
the first interest payment date under this Note.

PRIOR NOTE.26.

GENERAL PROVISIONS.Lender may delay or forgo enforcing any of its rights or remedies under this Note without losing
them. Borrower and any other person who signs, guarantees or endorses this Note, to the extent allowed by law, waive presentment, demand for payment, protest 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.

PRIOR TO SIGNING THIS NOTE, BORROWER READ AND UNDERSTOOD ALL THE PROVISIONS OF THIS NOTE, INCLUDING THE VARIABLE INTEREST RATE PROVISIONS. BORROWER AGREES TO
THE TERMS OF THE NOTE AND ACKNOWLEDGES RECEIPT OF A COMPLETED COPY OF THE NOTE.

BORROWER:

Transcrypt
International, Inc.

By:    /s/SCOTT W. AVERY

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Scott W. Avery, Treasurer

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