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                                                                  Exhibit 10(uu)
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                                  AMENDMENT OF
                     SUPPLEMENTAL PENSION BENEFIT AGREEMENT
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                  THIS AMENDING AGREEMENT made as of the 1st day of August, 1997
by and between ALLEN TELECOM INC., a Delaware Corporation, ("Allen") having its
principal executive offices at Beachwood, Ohio, and J. CHISHOLM LYONS, of
Burlington, Ontario, Canada ("Lyons").


                                    RECITALS
                                    --------

                  A. Allen maintains a retirement plan for employees designated
as the Allen Telecom Inc. Corporate Retirement Plan (the "Pension Plan"), which
is intended to meet the requirements of a "qualified plan" under the Internal
Revenue Code of 1986, as amended (the "Code"); and

                  B. Allen and Lyons have previously entered into a
Supplemental Pension Benefit Agreement, dated as of December 6, 1983 (the
"Pension Agreement") and amended as of December 20, 1990, intended to provide an
aggregate level of non-qualified and qualified pension benefits payable under
the Pension Plan, whether or not such Pension Plan benefits are limited in
amount by provisions of the Code affecting qualified plans only.

                  NOW, THEREFORE, in consideration of the premises and of
Lyons' services and significant contributions to Allen, the parties hereto
agree as follows:

                                       I.

               Paragraph 3 of the Pension Agreement is hereby amended by the
addition of a new paragraph following the first paragraph thereof as follows:

               "Lyons may elect to receive his remaining Supplemental Pension
          Benefit in a single cash lump sum payment. If Lyons so elects, the
          amount to be paid to him shall be equal to the actuarial present value
          of all remaining Supplemental Pension Benefit payments calulated as of
          the date of such payment reduced by ten percent (10%). The remaining
          ten percent (10%) of the actuarial present value of all remaining
          Supplemental Pension Benfit payments shall be forfeited."


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                                       II.

               Paragraph 4 of the Pension Agreement is hereby amended in its
entirety to read as follows:

               "4. Allen shall not be required to fund, or otherwise segregate
          assets to be used for payment of the Supplemental Pension Benefits
          hereunder. Allen may, in its sole discretion, establish a trust to
          hold assets or other property to be used in payment of Supplemental
          Pension Benefits hereunder; provided, however, that any funds or other
          property contained therein shall remain liable for the claims of
          Allen's general creditors. The obligations which Allen incurs
          hereunder may be satisfied only out of its general corporate funds.
          Nothing contained herein, and no action taken pursuant to the
          provisions of this Pension Agreement, shall create or be construed to
          create a trust of any kind or a fiduciary relationship between Allen
          and Lyons, his designated beneficiary or any other person."

                                 *.*.*.*.*


               Except as herein specifically amended the Pension Agreement is
ratified and confirmed.

               This Amending Agreement and the Pension Agreement as previously
amended shall be read, interpreted and construed as a single
agreement.

               IN WITNESS WHEREOF, Allen Telecom Inc. has caused this Amending
Agreement to be signed by its proper officer and Lyons has hereunto set his
hand this 1st day of August, 1997.


ATTEST                         ALLEN TELECOM INC.


                               By:
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Secretary                      Title:
                                     ----------------------------

WITNESS:                          J. Chisholm Lyons
/s/                            /s/ J. Chisholm Lyons
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