EXHIBIT 10.66

                          STANDBY CONSULTING AGREEMENT


         This Standby Consulting Agreement (this "Agreement") is entered into as
of September 1, 1998 (the "Effective  Date") by and between  Trimble  Navigation
Limited,  a California  corporation  (the  "Company"),  and Dr. Robert S. Cooper
("Consultant").

         WHEREAS,  simultaneously  with the  execution  hereof,  the Company and
Consultant are entering an Employment Agreement (the "Employment Agreement");

         WHEREAS,  the  Company,   immediately   following  the  termination  of
Consultant's status as an employee under the Employment  Agreement,  the Company
desires to retain the ability to use Consultant as an independent  contractor to
perform  consulting  services for the Company as the need for such  services may
arise from time to time and Consultant is willing to perform such  services,  on
terms set forth more fully below;

         NOW,  THEREFORE,  in  consideration  of the mutual  promises  contained
herein, the parties agree as follows:

         1.       Services and Compensation

                  (a) Services. Consultant will perform consulting services (the
"Services") on as needed basis as determined by the Chief  Executive  Officer of
the Company in consideration for $1.00 per year.

                  (b) Compensation. The Company will pay Consultant on an hourly
basis at a rate  mutually  determined  by  Consultant  and the  Chief  Executive
Officer of the Company at the time the Services are performed.

                  (c) Expenses.  The Company will  reimburse  Consultant for all
reasonable  travel  expenses  incurred  by  Consultant  in  performing  Services
pursuant to this Agreement.

         2.       Confidentiality

                  (a) Definition.  "Confidential  Information" means any Company
proprietary information,  technical data, trade secrets or know-how,  including,
but not limited to,  research,  product plans,  products,  services,  customers,
customer  lists,  markets,  software,   developments,   inventions,   processes,
formulas,  technology,  designs, drawings,  engineering,  hardware configuration
information,  marketing, finances or other business information disclosed by the
Company  either  directly or  indirectly  in  writing,  orally or by drawings or
inspection of parts or equipment.


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                  (b) Non-Use and Non-Disclosure. Consultant will not, during or
subsequent  to the  term  of this  Agreement,  use  the  Company's  Confidential
Information  for any  purpose  whatsoever  other  than  the  performance  of the
Services  on  behalf of the  Company  or  disclose  the  Company's  Confidential
Information  to  any  third  party.  It is  understood  that  such  Confidential
Information  will remain the sole  property of the Company.  Consultant  further
agrees to take all reasonable precautions to prevent any unauthorized disclosure
of such  Confidential  Information  including,  but not limited to,  having each
employee of  Consultant,  if any, with access to any  Confidential  Information,
execute a nondisclosure  agreement containing  provisions in the Company's favor
identical  to Sections 2, 3 and 4 of this  Agreement.  Confidential  Information
does not include  information  which (i) is known to  Consultant  at the time of
disclosure  to  Consultant  by the Company as  evidenced  by written  records of
Consultant,  (ii) has become publicly known and made generally available through
no  wrongful  act of  Consultant,  or (iii)  has  been  rightfully  received  by
Consultant from a third party who is authorized to make such disclosure. Without
the Company's prior written approval, Consultant will not directly or indirectly
disclose to anyone the existence of this  Agreement or the fact that  Consultant
has this arrangement with the Company.

                  (c) Former  Employer's  Confidential  Information.  Consultant
agrees that  Consultant  will not  improperly  use or disclose  any  proprietary
information  or trade secrets of any former or current  employer or other person
or entity with which  Consultant  has an agreement or duty to keep in confidence
information  acquired by Consultant,  if any, and that Consultant will not bring
onto the  premises  of the  Company  any  unpublished  document  or  proprietary
information belonging to such employer,  person or entity unless consented to in
writing  by such  employer,  person or entity.  Consultant  will  indemnify  the
Company and hold it harmless from and against all claims,  liabilities,  damages
and expenses, including reasonable attorneys fees and costs of suit, arising out
of or in connection  with any violation or claimed  violation of a third party's
rights  resulting in whole or in part from the Company's use of the work product
of Consultant under this Agreement.

                  (d)   Third   Party   Confidential   Information.   Consultant
recognizes  that the Company has  received  and in the future will  receive from
third parties their confidential or proprietary information subject to a duty on
the Company's part to maintain the  confidentiality  of such  information and to
use it only for certain limited purposes. Consultant agrees that Consultant owes
the  Company  and such  third  parties,  during the term of this  Agreement  and
thereafter,  a duty to hold all such confidential or proprietary  information in
the  strictest  confidence  and  not to  disclose  it to  any  person,  firm  or
corporation  or to use it except as  necessary  in carrying out the Services for
the Company consistent with the Company's agreement with such third party.

                  (e)  Return  of  Materials.   Upon  the  termination  of  this
Agreement,  or upon Company's  earlier  request,  Consultant will deliver to the
Company  all  of  the  Company's  property  or  Confidential   Information  that
Consultant may have in Consultant's possession or control.

         3.       Ownership


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                  (a)  Assignment.  Consultant  agrees  that  all  copyrightable
material,  notes,  records,   drawings,   designs,   inventions,   improvements,
developments,   discoveries  and  trade  secrets  (collectively,   "Inventions")
conceived,  made or discovered by Consultant,  solely or in  collaboration  with
others,  during the period of this  Agreement  which relate in any manner to the
business  of  the  Company  that   Consultant  may  be  directed  to  undertake,
investigate or experiment with, or which  Consultant may become  associated with
in work,  investigation or experimentation in the line of business of Company in
performing  the  Services  hereunder,  are the  sole  property  of the  Company.
Consultant  further  agrees to assign (or cause to be assigned)  and does hereby
assign fully to the Company all Inventions  and any  copyrights,  patents,  mask
work rights or other intellectual property rights relating thereto.

                  (b) Further  Assurances.  Consultant agrees to assist Company,
or its  designee,  at the Company's  expense,  in every proper way to secure the
Company's rights in the Inventions and any copyrights, patents, mask work rights
or other intellectual property rights relating thereto in any and all countries,
including the  disclosure to the Company of all pertinent  information  and data
with respect thereto, the execution of all applications,  specifications, oaths,
assignments and all other  instruments  which the Company will deem necessary in
order to apply for and obtain  such  rights and in order to assign and convey to
the Company, its successors,  assigns and nominees the sole and exclusive right,
title and interest in and to such Inventions, and any copyrights,  patents, mask
work rights or other intellectual  property rights relating thereto.  Consultant
further agrees that Consultant's  obligation to execute or cause to be executed,
when it is in  Consultant's  power to do so, any such  instrument or papers will
continue after the termination of this Agreement.

                  (c) Pre-Existing  Materials.  Consultant agrees that if in the
course of performing the Services,  Consultant  incorporates  into any Invention
developed hereunder any invention, improvement,  development, concept, discovery
or other proprietary  information owned by Consultant or in which Consultant has
an interest, (i) Consultant will inform Company, in writing before incorporating
such  invention,   improvement,   development,   concept,   discovery  or  other
proprietary  information  into any  Invention  and (ii) the  Company  is  hereby
granted  and will have a  nonexclusive,  royalty-free,  perpetual,  irrevocable,
worldwide license to make, have made,  modify, use and sell such item as part of
or in  connection  with such  Invention.  Consultant  will not  incorporate  any
invention,  improvement,  development,  concept,  discovery or other proprietary
information  owned by any third party into any Invention without Company's prior
written permission.

                  (d) Attorney in Fact. Consultant agrees that if the Company is
unable because of Consultant's unavailability,  dissolution,  mental or physical
incapacity,  or for any other reason, to secure Consultant's  signature to apply
for or to pursue any  application  for any United  States or foreign  patents or
mask work or copyright  registrations  covering the  Inventions  assigned to the
Company above,  then Consultant hereby  irrevocably  designates and appoints the
Company and its duly authorized  officers and agents as  Consultant's  agent and
attorney in fact, to act for and in Consultant's behalf and stead to execute and
file  any such  applications  and to do all  other  lawfully  permitted  acts to
further  the  prosecution  and  issuance  of  patents,  copyright  and mask work
registrations  thereon  with the same legal  force and effect as if  executed by
Consultant.

         4. Conflicting Obligations. Consultant certifies that Consultant has no
outstanding  agreement  or  obligation  that  is in  conflict  with  any  of the
provisions of this Agreement,  or that would preclude  Consultant from complying
with the provisions hereof, and further certifies that Consultant will not enter
into any such conflicting agreement during the term of this Agreement.


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         5.  Non-Solicit.  The Consultant  covenants and agrees with the Company
that during his consultancy  with the Company and for a period expiring one year
after the date of  termination of such  consultancy,  he will not solicit any of
the Company's  then-current  employees to terminate  their  employment  with the
Company or to become  employed  by any other  firm,  company  or other  business
enterprise with which the Consultant may then be connected.

         6.       Term and Termination

                  (a) Term. This Agreement will commence  immediately  following
the  termination  of  Consultant's  status as an employee  under the  Employment
Agreement or as a consultant  under the Consulting  Agreement (as defined in the
Consulting Agreement) and will continue for a period of five years from the date
of this Agreement.

                  (b) Termination.  The Company may not terminate this Agreement
unless Consultant is in breach of any material provision of this Agreement.

                  (c) Survival.  Upon such  termination all rights and duties of
the parties toward each other will cease except:

                           (i)      that the Company will be obliged to pay, 
within 30 days of the effective date of  termination,  all amounts owing to 
Consultant  for Services  completed and accepted by the Company prior to the
termination date and related  expenses,  if any, in accordance with the
provisions of Section 1 (Services and Compensation) hereof; and

                           (ii)     Sections 2  (Confidentiality),  
3 (Ownership),  5 (Non-Solicit) and 8 (Independent Contractor) will survive 
termination of this Agreement.

         7.  Assignment.  Neither  this  Agreement  nor any right  hereunder  or
interest herein may be assigned or transferred by Consultant without the express
written consent of the Company.

         8. Independent  Contractor.  It is the express intention of the parties
that Consultant is an independent contractor.  Nothing in this Agreement will in
any  way  be  construed  to  constitute  Consultant  as an  agent,  employee  or
representative  of  the  Company,  but  Consultant  will  perform  the  Services
hereunder as an independent contractor.  Consultant acknowledges and agrees that
Consultant  is  obligated  to report  as income  all  compensation  received  by
Consultant pursuant to this Agreement, and Consultant agrees to and acknowledges
the obligation to pay all  self-employment  and other taxes thereon.  Consultant
further  agrees to indemnify  and hold  harmless the Company and its  directors,
officers,   and  employees  from  and  against  all  taxes,   losses,   damages,
liabilities,  costs and  expenses,  including  attorney's  fees and other  legal
expenses,  arising  directly or indirectly  from (i) any negligent,  reckless or
intentionally wrongful act of Consultant or Consultant's  assistants,  employees
or agents,  (ii) a determination by a court or agency that the Consultant is not
an independent contractor, or (iii) any breach by the Consultant or Consultant's
assistants,  employees  or  agents  of any of the  covenants  contained  in this
Agreement.


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         9. Benefits. Consultant acknowledges and agrees and it is the intent of
the parties hereto that Consultant  receive no  Company-sponsored  benefits from
the Company either as a Consultant or employee.  Such benefits include,  but are
not  limited to,  paid  vacation,  sick  leave,  medical  insurance,  and 401(k)
participation.  If Consultant is  reclassified  by a state or federal  agency or
court as an employee,  Consultant  will become a reclassified  employee and will
receive no benefits  except those  mandated by state or federal law,  even if by
the  terms  of the  Company's  benefit  plans  in  effect  at the  time  of such
reclassification Consultant would otherwise be eligible for such benefits.

         10.      Arbitration and Equitable Relief

                  (a) Disputes.  Except as provided in Section 10(c) below,  the
Company and the  Consultant  agree that,  to the extent  permitted by applicable
law,  any  dispute  or  controversy  arising  under or in  connection  with this
Agreement will be settled exclusively by arbitration in San Jose, California, in
accordance with the rules of the American Arbitration Association then in effect
by an arbitrator selected by both parties within ten days after either party has
notified  the other in  writing  that it  desires a dispute  between  them to be
settled by arbitration. In the event the parties cannot agree on such arbitrator
within such ten-day period,  each party will select an arbitrator and inform the
other party in writing of such  arbitrator's  name and address  within five days
after the end of such ten-day  period and the two  arbitrators  so selected will
select a third arbitrator within 15 days thereafter;  provided, however, that in
the event of a failure by either  party to select an  arbitrator  and notify the
other  party of such  selection  within  the time  period  provided  above,  the
arbitrator  selected  by the  other  party  will be the sole  arbitrator  of the
dispute.  The  decision  of  the  arbitrator  or a  majority  of  the  panel  of
arbitrators  will be binding  upon the parties and judgment in  accordance  with
that  decision  may be  entered  in any  court  having  jurisdiction  thereover.
Punitive damages will not be awarded.

                  (b) Consent to Personal  Jurisdiction.  The arbitrator(s) will
apply California law to the merits of any dispute or claim, without reference to
conflicts of law rules.  Consultant hereby consents to the personal jurisdiction
of the  state  and  federal  courts  located  in  California  for any  action or
proceeding  arising  from or  relating  to this  Agreement  or  relating  to any
arbitration in which the parties are participants.

                  (c)  Equitable  Relief.  The parties may apply to any court of
competent   jurisdiction  for  a  temporary   restraining   order,   preliminary
injunction,  or other interim or  conservatory  relief,  as  necessary,  without
breach of this arbitration agreement and without abridgment of the powers of the
arbitrator.

                  (d)  Acknowledgment.  CONSULTANT HAS READ AND UNDERSTANDS THIS
AGREEMENT,  WHICH DISCUSSES ARBITRATION.  CONSULTANT UNDERSTANDS THAT BY SIGNING
THIS AGREEMENT,  CONSULTANT AGREES TO SUBMIT ANY CLAIMS ARISING OUT OF, RELATING
TO, OR IN  CONNECTION  WITH THIS  AGREEMENT,  OR THE  INTERPRETATION,  VALIDITY,
CONSTRUCTION,   PERFORMANCE,   BREACH  OR   TERMINATION   THEREOF,   TO  BINDING
ARBITRATION,  EXCEPT AS PROVIDED  IN SECTION  10(c),  AND THAT THIS  ARBITRATION
CLAUSE CONSTITUTES A WAIVER OF CONSULTANT'S RIGHT TO A JURY TRIAL AND RELATES TO
THE  RESOLUTION  OF ALL  DISPUTES  RELATING TO ALL  ASPECTS OF THE  RELATIONSHIP
BETWEEN THE PARTIES.


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         11.  Governing  Law.  This  Agreement  will be governed by the internal
substantive laws, but not the choice of law rules, of the State of California.

         12.  Entire  Agreement.  This  Agreement and the  Employment  Agreement
represent the entire agreement and  understanding  between the parties as to the
subject  matter  hereof and supersede all prior  agreements  whether  written or
oral. No waiver,  alteration,  or  modification of any of the provisions of this
Agreement will be binding unless in writing and signed by the party against whom
enforcement of the change or modification is sought.

         13.  Attorney's  Fees.  In any court  action at law or equity  which is
brought by one of the parties to enforce or  interpret  the  provisions  of this
Agreement,  the prevailing party will be entitled to reasonable attorney's fees,
in addition to any other relief to which that party may be entitled.

         14.  Severability.  The invalidity or unenforceability of any provision
of this  Agreement,  or any terms thereof,  will not affect the validity of this
Agreement as a whole, which will at all times remain in full force and effect.

         15. Counterparts.  This Agreement may be executed in counterparts, each
of which  will be  deemed  an  original,  and  which  together  will be a single
instrument.


         IN WITNESS WHEREOF,  the parties hereto have executed this Agreement as
of the day and year first above written.


CONSULTANT:                         TRIMBLE NAVIGATION LIMITED

By: /s/ Robert S. Cooper            By: Bradford W. Parkinson            
Dr. Robert S. Cooper
                                    Name: Bradford W. Parkinson     

                                    Title: President  


                                   Address: 585 N. Mary Avenue
                                   P.O. Box 3642
                                   Sunnyvale, CA  94088-3642

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