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[SATMEX LOGO]                                                       EXHIBIT 10.5


                                                          CONTRACT NUMBER: 266-1

CONTRACT FOR RENDERING OF THE INTERNATIONAL SERVICE OF SIGNAL CONDUCTION VIA
SATELLITE THROUGH THE MEXICAN SATELLITE SYSTEM ("SISTEMA DE SATELITES
MEXICANOS"), ENTERED INTO BY AND BETWEEN SATELITES MEXICANOS, S.A. DE C.V.,
WHICH SHALL HEREINAFTER BE NAMED "SATMEX", REPRESENTED IN THIS ACT BY MR. LAURO
ANDRES GONZALEZ MORENO, IN HIS CAPACITY AS CHIEF EXECUTIVE OFFICER (C.E.O.),
AND AS THE OTHER PARTY BY AMERICAN MULTIPLEXER CORPORATION, WHICH SHALL
HEREINAFTER BE NAMED "THE CLIENT", REPRESENTED BY MR. EDWARD SC TAN, IN HIS
CAPACITY AS PRESIDENT AND CHIEF EXECUTIVE OFFICER, PURSUANT TO THE FOLLOWING
DECLARATIONS AND CLAUSES:

                                  DECLARATIONS

I.-    "SATMEX" DECLARES:

I.1    That it is a Variable Capital Stock Corporation ("Sociedad Anonima de
       Capital Variable"), duly incorporated in accordance with Mexican law.

I.2    That according to the provisions of the Mexican Federal
       Telecommunications Law ("Ley Federal de Telecomunicaciones"), and in the
       Mexican Regulations of Communication Via Satellite ("Reglamento de
       Comunicacion Via Satelite"), occupation of the 109.2 degrees, 113.0
       degrees and 116.8 degrees West longitude geostationary orbit positions
       was concessioned on behalf of "SATMEX" for exclusive exploitation of the
       "C" and "Ku" frequency bands and the rights of transmission and reception
       of signals.

I.3    That Mr. Lauro Andres Gonzalez Moreno, in his capacity as C.E.O., has
       faculties to subscribe this Contract.

I.4    That it meets the technical and economic conditions to take on commitment
       of the provision of the service covered by this Contract.

I.5    That its Federal Taxpayer Registration Number is: SME-970626 MK5.

I.6    That for the exercise and fulfillment of the rights and obligations under
       its care, derived from entering into this Contract, it indicates as its
       address that located on Boulevard Manuel Avila Camacho No. 40, piso 23,
       Colonia Lomas de Chapultepec, C.P. 11000, Mexico Distrito Federal.

II.-   "THE CLIENT" DECLARES:

II.1   That it is a Corporation, duly Incorporated under the laws of the State
       of North Carolina, United States of America.

II.2   That Mr. Edward SC Tan, in his capacity as President and Chief Executive
       Officer, has faculties to subscribe this Contract.

II.3   That it is presenting a certified and a simple copy of the documentation
       indicated in the foregoing declarations.


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II.4    That any modification on its firm name and/or the power of attorney
        granted to Its President and Chief Executive Officer shall be
        communicated in a timely manner and in writing to "SATMEX."

II.5    That it complies with the applicable legislation in the countries
        comprised within the NAFTA, Ku1 region of the Satmex 5 satellite where
        the service shall operate, and that it has obtained the necessary
        authorization(s) from the corresponding regulating institutions, to
        install, operate or exploit the transmitting and/or receiving ground
        station or stations.

II.6    That it accepts the "General Provision Conditions of the Satellite
        Signal Carrying Permanent Service through the Mexican Satellite System",
        issued by "SATMEX" (Annex I), as well as the Technical Annex (Annex
        II), which, duly signed by the parties, are added to this Contract, to
        form an integral part of same.

II.7    That is acquainted with the established legal framework, in the
        Mexican and international settings, to which rendering of the service
        subject matter of this Contract is subject, and is bound to use the
        service rendered by "SATMEX" to cover its communication needs within
        that legal framework.

II.8    That it indicates as its address, for all effects of this Contract,
        that located on: 575 North Pastoria Avenue, Sunnyvale, California
        94086, United States of America.

After having effected the foregoing declarations, the parties agree to enter
into this Contract and bind themselves pursuant to the following:

                                 C L A U S E S

FIRST. - According to the terms, conditions, and technical, legal and tariff
modalities contained in this Contract and its Annexes, "SATMEX" is bound to
provide to "THE CLIENT" the international service of signal conduction via
satellite, through the Mexican Satellite System, by means of the space segment
assignation in the category of Non-Preemptible service, on the Ku band, of the
NAFTA Ku1 region, of the Satmex 5 satellite, with a total bandwidth of 72.00
MHz, according to the following calendar.

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------
                                        BANDWIDTH            TRANSPONDER
-----------------------------------------------------------------------------
<S>                                      <C>                     <C>
From September 1st, 1999 to              36 MHz                  2 K
  December 31st, 1999
-----------------------------------------------------------------------------
From January 1st, 2000 to                72 MHz                  4 K
  December 31st, 2004
-----------------------------------------------------------------------------
</TABLE>

Should "THE CLIENT" wish to increase its capacity in a third, fourth and/or
fifth transponder, "THE CLIENT" shall give written notice to "SATMEX" sixty
(60) days prior to the start of service. All capacity in subject to
availability.

If "THE CLIENT" notifies "SATMEX" of such increments before November 15th,
1999, "THE CLIENT" shall have the following payment conditions:

Transponder 3: USD$ 148,400.00, for which service shall start no later than
June 1st, 2000.
Transponder 4: USD$ 145,040.00, for which service shall start no later than
September 1st, 2000.
Transponder 5: USD$ 141,600.00, for which service shall start no later than
December 1st, 2000.

                                       2



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These increments shall be added via amendments to this contract.

If "THE CLIENT" decides to increase its capacity but subsequently such
transponder(s) is(are) not taken on specified date(s),  "THE CLIENT" shall pay
"SATMEX" a penalty equal to five (5) monthly payments for each transponder at
the monthly transponder rate for said transponder, which shall be payable within
the following thirty (30) calendar days in which service would have begun.

SECOND.- "SATMEX" shall assign to "THE CLIENT" the satellite access
frequencies and their respective operation parameters, on the basis of the link
calculations previously presented by "THE CLIENT" to "SATMEX" for each
transmission and/or reception carrier on which the ground stations that form
part of its network shall access.

"SATMEX" may modify the frequencies assigned to "THE CLIENT" for justified
reasons or optimization movements of the space segments on the corresponding
satellite, for which it shall give "THE CLIENT" timely written notice of the
respective modifications. "THE CLIENT" is bound to carry out location changes
and release the preceding frequencies within the term jointly agreed.

The satellite, band, coverage region, transponder, polarization, link points,
satellite frequencies, operation parameters, location of the ground stations,
antenna diameters, are described in Annex II, which shall be updated as  "THE
CLIENT" requests from "SATMEX" modifications or enlargements on the service
Contracted; in such case, the parties shall subscribe the respective Agreement.

THIRD.- "THE CLIENT" is bound to notify "SATMEX" in writing the name(s),
position(s), address(es), telephone number(s) and fax number(s) of the
technically responsible person(s) in charge of its company's satellite network,
at the latest within the first five (5) working days following the signature
hereof, or when said responsible persons are changed.

FOURTH.- "SATMEX" shall deliver the satellite access frequencies and its
operation parameters to "THE CLIENT", in writing, at the time this Contract is
signed.

FIFTH.- The ground station(s) through which the service is provided shall
satisfy the technical specifications and features set forth by "SATMEX" to
operate with the Mexican Satellite System, and shall fulfill among others,
recommendation ITU-R. S.580-5 and operate with agile and fractionary step
frequency synthesizers. The above shall be described in the technical memory of
the network delivered by "THE CLIENT" to "SATMEX."

SIXTH.- The invoicing of the service shall begin as of September 1st, 1999.

SEVENTH.- "SATMEX" shall send to the address declared by "THE CLIENT" the
monthly invoice of the service contracted, within the first five (5) working
days of each month, which shall be sent per month in advance.

In the event "THE CLIENT" does not receive the invoice at its address in a
timely manner, the latter shall notify this to the "SATMEX" collection area and
effect the corresponding payment.

EIGHTH.- If "THE CLIENT" is not in agreement with any invoice, it shall
immediately present its application for clarification and/or adjustment, in
writing, to "SATMEX", explaining the reasons and grounds for its disagreement.
Such event does not exempt "THE CLIENT" of its payment obligation.


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NINTH.- "THE CLIENT" shall guarantee to "SATMEX" fulfillment of this Contract,
for an amount equivalent to two (2) times the monthly payment of the service,
by means of a Letter of Credit issued by Bank of America, on behalf of "SATMEX"
(Satelites Mexicanos, S.A. de C.V.), for a total amount of USD$310,800.00
(three hundred and ten thousand eight hundred 00/100 U.S. Dollars), and which
shall be given in a term not to exceed five (5) working days following the
signature of this Contract.

The Letter of Credit shall be given under the terms of this Contract.

The term in force for the Letter of Credit shall be from the signing date of
the Contract and until sixty (60) calendar days following the expiration date
of this Contract and shall be an irrevocable documentary at sight.

The description of the service shall state: obligations assumed by "American
Multiplexer Corporation" on behalf of "Satelites Mexicanos, S.A. de C.V.",
proceeding from satellite services, as stated on Contract number: 266-I,
dated: October 1st, 1999.

Should "THE CLIENT" wish to increase its capacity in a third, fourth and/or
fifth transponder, as stated on Clause First, "THE CLIENT" shall increase its
guaranty payment for an amount equal to two times the monthly payment of the
third transponder: (USD$ 148,400.00), no longer than five (5) days after the
correspondent amendment is signed.

TENTH.- "THE CLIENT" is bound to pay to "SATMEX" for the service subject
matter of this Contract, in monthly payments in advance, the total amount of
USD$ 19,059,600.00 (nineteen million fifty-nine thousand and sixty hundred U.S.
Dollars), in accordance with the following calendar:

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------
                                    BANDWIDTH        ADVANCE MONTHLY PAYMENT
--------------------------------------------------------------------------------
<S>                                 <C>              <C>
From September 1st, 1999 to          36 MHz              USD$ 155,400.00
  December 31st, 1999
--------------------------------------------------------------------------------
From January 1st, 2000 to            72 MHz              USD$ 307,300.00
  December 31st, 2004
--------------------------------------------------------------------------------
</TABLE>

"THE CLIENT" is bound to make payments in a timely manner, at the latest on the
fifteenth (15th) day of each month, on the Citibank account established on
Section 16 of Annex I. "SATMEX" agrees to establish a Bank of America account
where "THE CLIENT" may make all payments for services from October 1999 through
expiration of this Contract. "THE CLIENT" will make payments through a wire
transfer by Bank of America to Citibank as established on Section 16 of Annex I
for September 1999 services.

If "THE CLIENT" ceases to cover one (1) monthly payment, the service shall be
suspended. As the case may be, for reactivation, "THE CLIENT" shall cover
previously the indebtedness, moratory interest and reconnection charges.

The parties agree that each of them shall pay the taxes and tariffs generated
under their care, according to the legal ordinances in force in their
respective countries.

When "THE CLIENT" ceases to cover more than one (1) monthly payment, "SATMEX"
may assign the capacity to another interested party.

ELEVENTH.- Moratory Interest shall be calculated on the basis of the rate
resulting from adding two (2) times the Prime Rate, issued by the New York
Citibank, proportionately to the days of delay in payment, divided into twelve
(12) months, on unpaid balances of the amounts owed monthly.


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Said interest shall be applied as of the day following the payment expiration
date and until the same is received by "SATMEX."

TWELFTH.- "SATMEX" shall only be liable, for compensation effects, for dolus,
for service interruptions in the part corresponding to the space segment,
facilities or equipment owned by it, but in no case for acts of god or force
majeure. "SATMEX's" responsibility, shall in no case, exceed the amount of the
guarantee given by "THE CLIENT".

In case of service supply interruption, "THE CLIENT" shall inform this
immediately to the "SATMEX" Satellite Control Center ("Centro de Control
Satelital") in order for the reason to be determined, the failure corrected,
and the service reestablished. Likewise, it shall notify "SATMEX" in writing so
that, as the case may be and on the basis of the Control Center's technical
report, the corresponding compensation is made to it, in accordance with the
stipulations of Section 18 of Annex I.

When it is necessary to provide maintenance to its facilities or equipment,
among others, "SATMEX" may interrupt the service, in coordination with "THE
CLIENT", and the latter shall not be entitled to any compensation. In any case,
"SATMEX" shall make its best efforts so that said interruptions cause the least
possible damage to "THE CLIENT".

If service interruptions arises, derived from operation of the ground stations
through which the service is provided, which stations are not authorized  or
technically approved and are causing interference, "SATMEX" shall not be bound
to grant compensations.

THIRTEENTH.- The term of this Contract shall be five (5) years and three
months counted from the date it is signed.

FOURTEENTH.- "THE CLIENT" may cancel part of the capacity contracted or
terminate this Contract, notifying this to "SATMEX", in writing, at least
thirty (30) working days in advance. In such case, the cancellation or
termination date shall be referred to a calendar month (last day of the month).

In the event "THE CLIENT" cancels part of the capacity contracted or terminates
this Contract before the end of the term in force indicated in CLAUSE
THIRTEENTH, the latter shall pay to "SATMEX", in one single payment and before
the date notified by "THE CLIENT" has elapsed, the amount resulting from the
tariff corresponding on a monthly basis to Contracts at one (1) year, for each
month remaining to conclude the time period originally agreed upon, not to
exceed twelve (12) months.

In the assumption of partial cancellation, the aforementioned payment shall be
applied to the capacity affected.

Advance cancellation or termination of a service does not release "THE CLIENT"
from previous indebtedness or moratory interest.

"SATMEX" reserves the right to assign the satellite capacity released due to
advance cancellation or termination to another interested party, as of the day
following the termination or cancellation date.


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FIFTEENTH.-  "SATMEX" may rescind this Contract for any of the following
             reasons:

    I.-     For any type of transmission of the rights and/or obligations
            derived from this Contract, made by "THE CLIENT" to third parties,
            without having prior written authorization from "SATMEX."

    II.-    If "THE CLIENT" stops paying more than one (1) monthly invoice of
            the service or for three (3) suspensions of same in the term of one
            (1) year.

    III.-   If "THE CLIENT" does not adjust to satellite access parameters
            indicated by "SATMEX."

    IV.-    If "THE CLIENT" does not attend approximately and/or carry out the
            necessary adjustments on the generated signals on their equipment
            that cause or may cause affectations to third parties.

    V.-     If "THE CLIENT" does not grant or maintain the guarantee mentioned
            in CLAUSE NINTH in time and form.

    VI.-    For dissolution or liquidation of "THE CLIENT", or if it is
            declared in bankruptcy or suspension of payments, or if it is in
            any of the cases stipulated in Article 2nd of the Mexican Law of
            Bankruptcy and Suspension of Payments ("Ley de Quiebras y
            Suspension de Pagos").

    VII.-   If "THE CLIENT" decides not to accept the relocation assigned to it
            by "SATMEX" in its satellites.

    VIII.-  In general, because "THE CLIENT" does not fulfill any of the
            obligations derived from this Contract, as well as its Annexes.

SIXTEENTH.- If "THE CLIENT" incurres in any of the causes of rescission
indicated in the preceding clause, "SATMEX" shall communicate this in writing so
that in a maximum term of fifteen (15) calendar days, "THE CLIENT" amends the
breach of its obligation. If after said term has elapsed "THE CLIENT" has not
amend the breach of its obligation, "SATMEX" may rescind this Contract, without
a court order.

In the event "SATMEX" rescinds this Contract, "THE CLIENT" is bound to perform
the payment referred to in CLAUSE FOURTEENTH and release the satellite capacity
mentioned in CLAUSE FIRST; in such case, "SATMEX" shall have the possibility
to relocate such capacity immediately.

SEVENTEENTH.- "SATMEX" shall not incur any liability whatsoever for damages
suffered by "THE CLIENT" or third  parties, in a specific but not limiting
manner, for delay in delivery, deficient functioning or failures that might
appear in the space segment subject matter of this Contract, as well as service
interruptions in the part corresponding to the space segment or equipment owned
by it, derived from acts of God or force majeure.

EIGHTEENTH.- Both parties are bound to maintain all of the information and
documentation exchanged between them, by virtue of the fulfillment and execution
of this Contract, as strictly confidential, except: (i) if same is requested by
a judicial or administrative authority and/or (ii) if said information is
deemed to be of public knowledge.

The parties may use the confidential information only by means of prior written
consent from the other party.

NINETEENTH.- This contract only covers the service provided by "SATMEX", "THE
CLIENT" being committed to obtain the authorization of permit/license, whose
granting is a faculty of the corresponding governing bodies at the site of the
ground station(s), on its own behalf.


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TWENTIETH.- IN case of controversy regarding the fulfillment, contents,
construction and scope of the obligations in this Contract, the parties submit
to the indications of the ordinance in force for the Federal District and the
jurisdiction and competence of the Courts of Mexico City, thus waiving their
right to the jurisdiction that might correspond to them due to their present or
future address or for any other reason. The official language for these
purposes is Spanish.

This Contract is signed in counterparts, one copy remaining in possession of
either party, in Mexico City, as of October 1st, 1999.




            FOR "SATMEX"                        FOR "THE CLIENT"


    /s/ LAURO GONZALEZ MORENO                   /s/ EDWARD SC TAN
    MR. LAURO GONZALEZ MORENO                   MR. EDWARD SC TAN
     CHIEF EXECUTIVE OFFICER.              PRESIDENT AND CHIEF EXECUTIVE
                                                    OFFICER



                                       7
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                                                                         ANNEX 1


                                        CLIENT: AMERICAN MULTIPLEXER CORPORATION
                                                          CONTRACT NUMBER: 266-I


              GENERAL PROVISION CONDITIONS OF THE SATELLITE SIGNAL

        CARRYING PERMANENT SERVICE THROUGH THE MEXICAN SATELLITE SYSTEM


GENERAL PROVISIONS.

     1.   The service to be provided by SATMEX consists of the carrying of
          signals by satellite on the C and Ku bands of the Mexican Satellite
          System, abiding by the provisions of the Concession Title, the Mexican
          Federal Law on Telecommunications, the Satellite Communication
          Regulations, the Mexican Federal Law on Radio and Television and its
          Regulations, the Constitution and Agreement of the UTI, the
          International Telecommunications Regulations, International Treaties
          and Agreements on the matter approved by the Senate of the Republic
          and any other administrative provisions on the matter.

     2.   The definitions of the technical terms used in the contracts and/or
          agreements, should be understood according to the documents already
          indicated in the above paragraph, the definitions that may be issued
          by the Telecommunications, Radio communications and Development
          Standardization Sectors of the UTI, as well as the correspondent
          Glossary of Terms of the Federal Telecommunications Commission and/or
          of Telecomunicaciones de Mexico.

     3.   THE CLIENT shall be responsible for obtaining and possessing the
          necessary concessions, permits, licenses or authorizations from the
          Mexican Federal Government or from the authorities on the matter in
          each country to be linked.


PROVISION.

     4.   The permanent service shall be provided based two categories,
          according to their continuity priority in case of contingency or
          partial or total failure of the assigned satellite, these being:

          NON-PREEMPTIBLE SERVICE - Is the one whose transponder has back-up
          amplifiers and is not interrupted to give priority to a protected
          service, but does not possess, in the case of fault, immediate
          protection in another transponder or satellite.

          INTERRUPTIBLE SERVICE - Is the one subject to be required at any time
          due to being used to provide immediate protection to a protected
          service and even to a Non-Preemptible service, due to the latter
          being considered as priorities. During normal operation, the
          transponder possesses backup transponders.

          Protected Service shall be provided only for the State satellite
          capacity; and it is used for national security and social benefit
          services, and has maximum priority over any service category, in case
          of contingency.

          Each category of the permanent service has a different tariff, which
          is defined in Annex II of the respective contract.

     5.   The space segment by which the service is provided shall be assigned
          based on the carriers of information and transmission for
          standardized integrated velocities, for complete transponders or
          fractions of band widths and/or transponder power, measured in
          Megahertz (MHz) and decibel Watts (dBw), respectively.



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6.   THE CLIENT, when contracting the service, must deliver a technical
     specifications sheet describing the network, its topology, the ground
     stations and their equipment, the satellite access technique, the required
     capacity and link calculation for each carrier, according to the format
     which shall be previously given thereto by SAMTEX.

7.   The frequency synthesizers of THE CLIENT's ground stations must be
     efficient and stepped in Kilohertz. The operation of equipment for
     crystal-syntonized frequencies or with tuning limitations are not
     acceptable, as this prevents the relocation of the service in case of
     interference and may also lead to greater consumption of band width,
     charged to THE CLIENT.

8.   The responsible technicians appointed by THE CLIENT to operate the ground
     stations of its satellite network, must not exceed the nominal satellite
     access parameters assigned to each carrier. The personnel of the Primary or
     Alternate Satellite Control Center of SATMEX, when detecting excesses,
     shall immediately coordinate the necessary rectifications with the manager
     of the ground station or the network. In the case that THE CLIENT does not
     make the necessary rectifications or deactivation of the carriers that
     operate out of the parameters, it shall be charged economic penalties for
     the use of excess power or bandwidth, or for the damages caused to other
     clients.

     The economic penalty shall be for the amount resulting from applying the
     highest tariff for the affected bandwidth and/or power, and also, in such
     case, the economic compensations amounts that SATMEX gives to an affected
     client(s). The payment of such penalties does not imply authorization to
     continue operating the service out of the assigned access parameters.


     If THE CLIENT, for reliability in its link(s), requires operation with a
     higher satellite power level, it may request (with link calculations) that
     SATMEX authorize it, if such possibility exists, apply the corresponding
     adjustments in the bill.

9.   THE CLIENT, prior to accessing the satellite, must coordinate the necessary
     technical testing of their ground stations with the Primary or Alternate
     Satellite Control Center, according to the procedure and protocol
     established by SATMEX.

10.  The ground stations which do not meet the insulation tests, radiation
     pattern or other parameter which affects or may affect other signals or
     satellites, may not be authorized to operate with the satellites until they
     have been corrected, without this implying any responsibility for SATMEX.

     Additionally, if an already tested ground station starts to produce
     interference with other signals during its operation, it must suspend its
     access to the satellite until the complete rectification of such
     interference. In this case, THE CLIENT must provide every facility, so that
     jointly with the Primary or Alternate Control Center, do whatever proceeds
     to help it to eliminate the interference.

     In the case that the manager(s) of the ground station(s) through which the
     services is run does/do not comply with the indications of the Primary or
     Alternate Satellite Control Center of SATMEX in a timely fashion, to
     correct or deactivate the ground station which is producing the
     interference, THE CLIENT shall pay SATMEX a fine equivalent to one percent
     (1%) of the monthly tariff for each hour or fraction for the delay plus the
     equivalent of the compensations SATMEX would have to pay to other clients
     as a consequence of said interference.

     THE CLIENT is committed to supervise the operating status of the ground
     stations and to make sure that these do not produce interference to their
     own signals, other clients signals or other satellites.

11.  When a client's signals are affected by interference whose origin is
     unknown or undetermined which does not allow its immediate rectification,
     THE CLIENT shall have the option to be relocated, as soon as possible, to a
     free space so as to provide its communications with continuity.



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          This must be immediately reported to the monitoring areas of the
          Primary or Alternate Satellite Control Center of SATMEX, so that in
          coordination with the assignations area, it may attend and aid in the
          relocation activities. As the case may be, SATMEX shall notify THE
          CLIENT of the new frequencies and operating parameters, be they
          temporary or definitive.

          The costs incurred as a result of relocating the frequencies to the
          ground stations shall be paid by THE CLIENT.

     12.  Any modification to the service or change of location of the ground
          stations must be requested from SATMEX at least thirty (30) working
          days in advance, including the complement to the technical
          specifications sheet and the link calculations for the modified
          carriers or new sites.

          THE CLIENT must not make modifications to the service without prior
          coordination with SATMEX.

CONTRACTING.

     13.  To contract the service, THE CLIENT must possess a public network
          concession or permit, of the type envisaged in Articles 24 and 31 of
          the Mexican Federal Law on Telecommunications, respectively and
          pursuant to the provisions of the Satellite Communication Regulations.
          The obtention of such permits shall be the responsibility of and at
          the cost of THE CLIENT. A copy of this document must be presented to
          SATMEX.

BILLING.

     14.  When the magnitude of any of the concepts used as the basis for the
          application of the tariff results in fractions greater than those
          established in the same, these shall be converted into unit, decimal
          or centesimal values, rounded up to the nearest higher number, as
          corresponds.

     15.  The invoices for the concept of the provision of permanent services
          shall be formulated for periods that correspond to one calendar month,
          except when the start of the service is on a day in the middle of the
          month, in which case the initial invoice shall be formulated for the
          amount corresponding to the number of days remaining for the
          conclusion of such month in which the service is provided.

     16.  THE CLIENT shall pay the invoices under its charge, at the latest in
          the date established in the correspondent invoice and in the same
          currency as shown in such documents. THE CLIENT shall have the option
          to pay in the banking institutions authorized by SATMEX or by an
          electronic bank transfer at SATMEX account at:

          Bank:                    Citibank, N.A.
          Domicile:                111 Wall Street, 10043, New York, N.Y.,
          Account number:          36184091,
          ABA number:              021000089.
          Beneficiary:             Satelites Mexicanos, S.A. de C.V.

COMPENSATIONS.

     17.  SATMEX shall in no case bear economic responsibility for damages and
          injuries caused by the interruptions in the service to THE CLIENT or
          third parties.

          SATMEX shall not grant compensation for the interruptions in the
          service derived from the operation of the ground station(s) which are
          not technically authorized or approved and which cause interference,
          or for the total or partial suspension of an interruptible service due
          to providing immediate protection to a protected or uninterruptible
          service, which have priority thereover.


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          The compensations shall be taken into account starting from the date
          on which the Satellite Control Center of SATMEX issues the report
          confirming the causes that led to the interruption.

     18.  The interruptions in the provision of the service, imputable to
          SATMEX, shall be compensated in the following way:

          I.-    Only shall be compensated continuous interruptions of three (3)
          hours. The compensation shall be equal to one eighth of the billing
          corresponding to one (1) day. A fraction of one hour shall be
          calculated as a complete hour.

          II.-   SATMEX shall not take into consideration requests for
          compensation when the interruption is due to THE CLIENT's negligence,
          or a failure of the apparatus and equipment which are not the property
          of SATMEX and whose conservation and operation does not pertain
          thereto.

          III.-  The compensations, when applicable, shall be credited to THE
          CLIENT in the due account for the second and third months following
          the month in which the interruption occured.

          IV.-   Devolutions shall only be made in those cases in which it is
          impossible to apply the compensations to other periods or services
          contracted by THE CLIENT.


This Annex is signed in counterparts, one copy remaining in possession of each
party, in Mexico City, as of October 1st, 1999.



      FOR "SATMEX"                              FOR "THE CLIENT"


/s/ LAURO A. GONZALEZ MORENO                    /s/ EDWARD SC TAN
  MR. LAURO GONZALEZ MORENO                     MR. EDWARD SC TAN
          C.E.O.                         PRESIDENT AND CHIEF EXECUTIVE OFFICER


                                       11

<PAGE>   12
[SATMEX LOGO]

                                    ANNEX II
                                   SECTION 1

-------------------------------------------------------------------------------
CLIENT:                 AMERICAN MULTIPLEXER CORPORATION
-------------------------------------------------------------------------------
ADDRESS:              575 NORTH PASTORIA AVENUE, SUNNYVALE
-------------------------------------------------------------------------------
CITY:          LOS ANGELES, CALIFORNIA, UNITED STATES OF             94086
                             AMERICA
-------------------------------------------------------------------------------
CONTRACT:      266-1     DATE: OCTOBER 1st, 1999     PERIOD IN USE: 5 YEARS AND
                                                     3 MONTHS
-------------------------------------------------------------------------------
REPRESENTED:                   MR. EDWARD SC TAN
-------------------------------------------------------------------------------

                             TECHNICAL INFORMATION

-------------------------------------------------------------------------------
NETWORK:       POINT-POINT    BANDWIDTH:
                              FROM SEPT 1st, 1999 TO DEC 31st, 1999:  36MHz
                              FROM JAN 1st, 2000 TO DEC 31st, 2004:   72MHz
-------------------------------------------------------------------------------
EXPLOTATION:   PRIVATE NETWORK
-------------------------------------------------------------------------------
SATELLITE:     SATMEX 5    BAND:  Ku     SERVICE CATEGORY:   NON PREEMPTIBLE
-------------------------------------------------------------------------------
ORBITAL         116.8W     TRANSPONDER:  2K
POSITION:                                4K
-------------------------------------------------------------------------------
REGION:        NAFTA, Ku1
-------------------------------------------------------------------------------
TELEPORT(S):  UNITED STATES OF AMERICA
-------------------------------------------------------------------------------

                                      COST

-------------------------------------------------------------------------------
TOTAL AMOUNT USD $19,059,600.00

MONTHLY COST USD:

FROM SEPTEMBER 1st, 1999 TO DECEMBER 31st, 1999 THE AMOUNT OF $155,400.00.
FROM JANUARY 1st, 2000 TO DECEMBER 31st, 2004, THE AMOUNT OF $307,300.00.
-------------------------------------------------------------------------------



                                       12
<PAGE>   13

[SATMEX LOGO]

                                TECHNICAL ANNEX
                                   SECTION 2

SERVICE OF SIGNAL CONDUCTION
OPERATION PARAMETERS

<TABLE>
<S>              <C>                   <C>
                                                 CARRIERS
-----------      -------------         ----------------------------
SATELLITE:          SATMEX 5            TRANSP:              2K
-----------      -------------         ----------------------------
BAND:                 Ku                POL.:                H/V
-----------      -------------         ----------------------------
REGION:           NAFTA, Ku1            ACCESS TECHNIQUE: FDMA/SCPC
-----------      -------------         ----------------------------
</TABLE>

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
                                                CENTER               EIRP           INF.
                   LINK                       FREQUENCY                             RATE     MOD      FEC    AVAIL   POWER     BW
     --------------------------------------------------------------------------------------  TYPE    RATIO     %       %      (MHz)
     TRANSMIT    ANT    RECEIVE    ANT     UP/L      DOWN/L      UP/L      DOWN/L    (Kbps)
                                          (MHz)      (MHz)      (dBw)     (dBw)
------------------------------------------------------------------------------------------------------------------------------------
<S>   <C>      <C>     <C>        <C>    <C>        <C>        <C>       <C>       <C>       <C>     <C>     <C>      <C>     <C>
       SAN     4.5    CHICAGO,    0.8    14040.0    11740.0    78.88     51.53     30000     QPSK     0.67   99.80    100.00  38.00
 1  FRANCISCO           ILL.
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>

A)   THE TOTAL BANDWIDTH ASSIGNED IS:                               36 MHz
     PERCENTAGE EQUIVALENT:                                         100%

B)   PERCENTAGE OF TOTAL POWER ASSIGNED:                            100%

C)   ALL THE MASTER (HUB) AND REMOTES DISHES MUST COMPLY WITH RECOMMENDATION
     ITU-R.S.580-5, FOR WHICH THEY ARE OBLIGATED TO PRESENT THE PATTERN
     RADIATION TESTS THAT SATMEX'S CONTROL CENTER CONSIDERS CONVENIENT TO THAT
     EFFECT.

D)   SATMEX IS NOT RESPONSIBLE FOR ADJACENT SATELLITE INTERFERENCES DUE TO THE
     USE OF 0.8 M ANTENNAS DECLARED.

E)   THE TECHNICAL PARAMETERS FOR 4K TRANSPONDER SHALL BE ASSIGNED BEFORE
     SERVICE STARTS.

THIS ANNEX IS SIGNED IN COUNTERPARTS, EACH COPY REMAINING IN POSSESSION OF EACH
PARTY IN MEXICO CITY, AS OF OCTOBER 1ST, 1999.

       FOR "SATMEX"                                 FOR "THE CLIENT"

/s/ LAURO GONZALEZ MORENO                          /s/ EDWARD SC TAN

MR. LAURO GONZALEZ MORENO                         MR. EDWARD SC TAN
          C.E.O.                             PRESIDENT AND CHIEF EXECUTIVE
                                                       OFFICER


                                       13