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                                                                 EXHIBIT 10.59


                              EMPLOYMENT AGREEMENT


     THIS EMPLOYMENT AGREEMENT (the "Agreement"), dated as of March 13, 1996
(the "Effective Date") is made by and between GTI Corporation, a Delaware
Corporation having its principal offices at 9171 Towne Centre Drive, Suite 460,
San Diego, California 92122-1229 (the "Company") and Albert J. Martinez
("Employee").

                                   AGREEMENT

  0. Effective Date.

     Employee's employment will commence on March 13, 1996.  The terms of this
agreement will become effective upon signature of this Agreement.  Employee's
employment relationship with the Company is at-will.

  1. Employment Duties.

     . Title/Responsibilities.  Employee shall hold the title of President and
Chief Executive Officer of the Company, and shall have the powers and duties
consistent with such position.  Employee shall also perform all duties which
from time to time are assigned to him by the Board of Directors ("Board").

     a.  Full Time Attention.  Employee shall devote substantially all of his
business time and attention, energy and skills to the Company during the time
he is employed under this Agreement.  The Company acknowledges that Employee
currently sits on the board of directors of the following companies: (1)
MicroChip Corporation, Arizona; and (2) UCSD Cancer Center, San Diego.  The
Company and Employee agree that no conflict of interest arises from Employee's
present board of director involvement.  Employee agrees to notify and obtain
approval from the Company's Board prior to accepting any additional board of
director positions.

     b.  Policy Compliance.  Employee is required to comply with the Company
policy, practice and procedure in effect during his employment.  The Company or
Employee may terminate the employment relationship for any reason or no reason.








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  2. Compensation.

     .   Base Salary.  The Company shall pay to Employee an initial annual Base
Salary of Three Hundred Thousand Dollars ($300,000).  Any increase to the
monthly Base Salary is within the sole discretion of the Company.

     a.  Bonus Compensation.  In addition to the compensation provided above, 
the Company will pay Employee an incentive bonus for each full year
starting with 1997 during the employment relationship.  For 1996, Employee is
eligible for a pro-rata portion of the annual targeted amount.  Such bonus
shall be calculated according to the Company Bonus Plan in effect at the time
of the calculation. Generally, Employee will receive fifty percent (50%) of
base salary if the Target is attained and up to a maximum of seventy five
percent (75%) of base salary if the Target is exceeded by twenty percent(20%). 
Bonuses are payable on March 1 of each year, provided Employee remains in his
position with the Company on that date.  All bonus arrangements are subject to
annual review and establishment by the Board.

     b.  Hiring Bonus.  Within seven (7) days of the commencement of Employee's
employment with the Company, the Company shall pay to Employee a net hiring
bonus of Fifteen Thousand Dollars ($15,000).

     c.  Stock Options.  Employee will be granted options to purchase 100,000
shares of the Company's common stock under the GTI Stock Incentive Plan (1989),
as amended, at a price which is the fair market value of the stock at close of
business on the date of commencement of employment, March 13, 1996.  The option
to purchase will remain open for as long as the Employee is in employment or
for 6 years from the grant, whichever is the shorter period.  Twenty percent
(20%) of the option shares will vest upon commencement of employment.  Of the
remaining eighty percent (80%), twenty percent (20%) of the option shares will
vest on each of the first four anniversaries after the grant.  The details of
this grant are formalized in the Stock Plan to be provided by the Company to
Employee.  In the event of an acquisition of the Company, including an offer by
Telemetrix to acquire one hundred percent (100%) of GTI, full vesting will
occur.

     d.  Fringe Benefits.

         (0) Vacation.  During the Term of this Agreement, Employee shall be
entitled to three (3) weeks (fifteen (15) working days) annual paid vacation in
addition to customary paid holidays.  Vacation will increase annually by one
day per year of service with a maximum of twenty (20) days of vacation per
year.  Employee may carry over unused vacation from the prior year, but will
cease to accrue vacation once he has accrued a maximum of forty



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(40) days.  Employee will not accrue any more vacation until he has taken
enough vacation to bring his accrued vacation below the maximum.

              (1) Health Benefits.  During his Employment, the Company agrees 
to provide Employee with comprehensive health insurance benefits.

              (2) 401K Participation. Employee may participate in any 401K or 
other employee retirement plan according to the requirements of those plans.

              (3) Life Insurance.  The Company shall maintain a term life 
insurance policy providing for payment of four (4) times base salary to 
Employee's designated beneficiaries should Employee die during his Employment.

              (4) Director and Officer Insurance.  During his term as Director
of the Company, Employee will be covered according to the terms of the Company's
Director and Officer Insurance.

              (5) Automobile.  During his employment, the Company agrees to 
provide Employee with an automobile allowance in the amount of $800.00 per month
towards an automobile to be used in connection with the Company's business.
Reasonable costs associated with the use of this automobile will be assumed by
the Company.

     e.  Reimbursement of Expenses.  During his Employment, with approval by the
Chairman of the Board, Employee shall be entitled to reimbursement of
reasonable and actual expenses, incurred on behalf of the Company, including
but not limited to travel and entertainment expenses, supplies and cellular
phone expenses.




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  3. Confidentiality.

     .   Proprietary Information.  Employee agrees that he will not disclose any
Proprietary Information (as hereinafter defined) to any individual or entity at
any time while he is employed by the Company or at any time thereafter, except
as is necessary and appropriate in the ordinary course of performing Employee's
duties to the Company during his employment under this Agreement, or unless
such disclosure has been authorized in writing by the Chairman of the Board, or
unless such disclosure is required by law.  For purposes of this Agreement, the
term "Proprietary Information" shall mean any information that was developed
by, became known by, or was assigned or otherwise conveyed to the Company, and
which has commercial value in the Company's business.  Proprietary Information
includes, but is not limited to, trade secrets, financial information, customer
lists and information, marketing plans, strategies, business forecasts,
computer programs, product plans, research and development information, testing
methods and results, inventions, improvements, formulas, processes, techniques,
designs, know-how and data.  Proprietary Information also includes, without
limitation, any information which is generally regarded as confidential in the
Company's industry or which is generally treated as confidential by the
Company.

     a.  Return Of Property.  Employee agrees that all documents, records,
apparatus, equipment and other physical property which is furnished or obtained
by Employee in the course of his employment with the Company shall be and
remain the sole property of the Company.  Employee agrees that, upon the
termination of his employment, he shall return all such property (whether or
not it pertains to Proprietary Information), and agrees not to make or retain
copies, reproductions or summaries of any such property.

  4. Non Competition.  During the term of his employment, Employee shall not,
directly or indirectly, either as an employee, employer, consultant, corporate
officer, director, or in any other individual or representative capacity,
engage or participate in any business that is in competition in with the
business of the Company in any location, unless such participation or interest
is fully disclosed to the Company and approved by the Board.

  5. Severance.  Employee shall be eligible for severance payments upon
termination of the employment relationship as follows:

     . Termination for Any Reason Other than Gross Misconduct.  As set forth
above, the employment relationship between the parties is at-will, terminable
by either party for any reason or no reason.  The Company may, nonetheless,
find that Employee has acted with gross misconduct in the performance of his
duties.  Where Employee is discharged for reasons other than gross misconduct,
death or disability, Employee is eligible for severance payments equivalent to
twelve months of base pay paid over a twelve (12) month period.




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     a.  Resignation.  Where Employee voluntarily resigns his employment at his
own initiative with the Company, the Company at its option may offer for
severance payments up to twelve (12) monthly payments of salary, if and only if
he agrees to extend the non-competition requirements set forth in paragraph 5
above for the severance period.  The Company reserves the right to cease any
remaining Severance Payments in the event Employee violates this Agreement.

     b.  Discharge after Gross Misconduct.  Where Employee is discharged as a
result of gross misconduct, he is not eligible for severance.

  6. Dispute Resolution Procedures:  Any controversy or claim arising out of
or relating to this Agreement or the breach thereof, or the interpretation
thereof, shall be settled by binding arbitration in accordance with the Rules
of the American Arbitration Association; and judgment upon the award rendered
in such arbitration shall be final and may be entered in any court having
jurisdiction thereof.  However, the selection of the arbitrator is not limited
to the AAA roster.  Notice of the demand for arbitration shall be filed in
writing with the other party to this Agreement and with the American
Arbitration Association.  In no event shall the demand for arbitration be made
after the date when institution of legal or equitable proceedings based on such
claim, dispute or other matter in question would be barred by the applicable
statute of limitations.  This agreement to arbitrate shall be specifically
enforceable under the prevailing arbitration law.  Any party desiring to
initiate arbitration procedures hereunder shall serve written notice on the
other party.  The parties agree that an arbitrator shall be selected pursuant
to these provisions within thirty (30) days of the service of the notice of
arbitration.  In the event of any arbitration pursuant to these provisions, the
parties shall retain the rights of all discovery provided pursuant to the
California Code of Civil Procedure, and the Rules thereunder.  All rights,
causes of action, remedies and defenses available under California law and
equity are available to the parties and shall be applicable as though in a
court of law.

  7. General Provisions.

     .   Governing Law.  This Agreement will be governed by and construed in
accordance with the laws of the State of California.

     a.  Assignment.  Employee may not assign, pledge or encumber his interest
in this Agreement or any part thereof.

     b.  No Waiver Of Breach.  The failure to enforce any provision of this
Agreement will not be construed as a waiver of any such provision, nor prevent
a party thereafter from enforcing the provision or any other provision of this
Agreement.  The rights granted the



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parties are cumulative, and the election of one will not constitute a waiver of
such party's right to assert all other legal and equitable remedies available
under the circumstances.

     c.  Severability.  The provisions of this Agreement are severable, and if
any provision will be held to be invalid or otherwise unenforceable, in whole
or in part, the remainder of the provisions, or enforceable parts of this
Agreement, will not be affected.

     d.  Entire Agreement.  This Agreement constitutes the entire agreement of
the parties with respect to the subject matter of this Agreement, and
supersedes all prior and contemporaneous negotiations, agreements and
understandings between the parties, oral or written.

     e.  Modification; Waivers.  No modification, termination or attempted
waiver of this Agreement will be valid unless in writing, signed by the party
against whom such modification, termination or waiver is sought to be enforced.

     f.  Fees and Expenses.  If any proceeding is brought for the enforcement or
interpretation of this Agreement, or because of any alleged dispute, breach,
default or misrepresentation in connection with any provisions of this
Agreement, the successful or prevailing party will be entitled to recover from
the other party reasonable attorneys' fees and other costs incurred in that
proceeding (including, in the case of an arbitration, arbitration fees and
expenses), in addition to any other relief to which such party may be entitled.

     g.  Amendment.  This Agreement may be amended or supplemented only by a
writing signed by both of the parties hereto.

     h.  Duplicate Counterparts.  This Agreement may be executed in duplicate
counterparts, each of which shall be deemed an original; provided, however,
such counterparts shall together constitute only one instrument.

     i.  Interpretation.  The headings contained in this Agreement are for
reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement.

     j.  Drafting Ambiguities.  Each party to this Agreement and its counsel 
have reviewed and revised this Agreement.  The rule of construction that any
ambiguities are to be resolved against the drafting party shall not be employed
in the interpretation of this Agreement or any of the amendments to this
Agreement.
     
     k.  English Language.  All reports, data, information, notices, schedules,
plans, records and other information required to be provided hereunder by
either party shall be in



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the English language. If a translation is made of this Agreement, it shall be
made for the convenience of the parties and the English language of this
Agreement shall be controlling.


Dated: March 13, 1996                        GTI Corporation
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                                       By:  /s/ Kenneth E. Maud
                                            -------------------
                                            Kenneth E. Maud, Chairman 
                                            of the Board




Dated: March 13, 1996                      /s/ Albert J. Martinez
       --------------                      ----------------------
                                           Albert J. Martinez






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