<PAGE>

                                                            EXHIBIT NUMBER 10.15

                                     LEASE

     THIS LEASE (hereinafter sometimes referred to as this "Lease" or this
"Agreement"), is made this day of August 17, 1998, by and between CHEROKEE
EQUITIES, LLC, a Colorado limited liability company having its principal place
of business at 5260 Mark Dabling, Colorado Springs CO. 80918 (hereinafter
referred to as "Landlord"), and STANFORD TELECOM CORPORATION, a Delaware
corporation maintaining its principal place of business at 1221 Crossman Avenue,
Sunnyvale, CA 94089-1117 (hereinafter referred to as "Tenant");

     WITNESSETH THAT:

     WHEREAS, Tenant desires to lease from Landlord upon the terms and
conditions set out herein, the real property described in Exhibit A and
illustrated in Exhibit B (the "Site Plan"), and improvements thereon, located in
the City of Colorado Springs, County of El Paso, State of Colorado; and

     WHEREAS, Landlord is willing to purchase and improve said real property and
to lease said real property and improvements to Tenant upon the terms and
conditions set out herein;

     NOW, THEREFORE, for and in consideration of the foregoing preambles, of the
mutual promises and covenants contained herein, of Ten Dollars ($10.00) in hand
paid by Tenant to Landlord, and of other good and valuable consideration, the
receipt and sufficiency of all of which is hereby acknowledged by both Landlord
and Tenant, Landlord and Tenant hereby agree as follows

                                   ARTICLE I
                Incorporation of Preambles - Certain Definitions

     1.01  Incorporation of Preambles. The foregoing preambles are hereby
incorporated into this Lease as a part hereof by this reference thereto.

     1.02 Certain Definitions. Reference is made in this Article 1.02 to certain
defined terms used herein, which are defined in the Articles referred to
opposite each such term, as follows:

Term                                              Article Where Defined
----                                              ---------------------
"Additional Rent"                                          Article 4.04
"Agreement"                                     Preambles, Article 1.01
"Base Rent"                                                Article 4.01
"Default Rate"                                         Article 18.03(c)
"Environmental Laws"                                   Article 26.01(a)
"Force Majeure"                                        Article 14.05(a)
"Improvements"                                               Article II
"Initial Term"                                             Article 3.01
"Landlord"                                      Preambles, Article 1.01
"Laws"                                                     Article XIII
"Lease"                                         Preambles, Article 1.01
"Lease Year"                                               Article 3.02
"Premises"                                                   Article II
"Regulated Substance"                                  Article 26.01(b)
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"Rent"                                                     Article 4.05
"Rent Adjustment Date"                                     Article 4.01
"Rent Commencement Date"                                   Article 3.04
"Site"                                          Preambles, Article 1.01
"Site Plan"                                       Preambles, Article II
"Tenant"                                        Preambles, Article 1.01
"Tenant's Building"                                          Article II
"Tenant's Property"                                           Article X
"Term"                                                     Article 3.03


                                   ARTICLE II
                               Lease of Premises

Landlord, for and in consideration of the rent to be paid and of the covenants
and agreements herein contained to be kept and performed by Tenant, does hereby
exclusively lease and demise to Tenant, and Tenant does hereby exclusively hire
from Landlord, on an absolute net basis, the real property being located in the
City of Colorado Springs, County of and State of Colorado described in Exhibit A
and illustrated on Exhibit B, including all improvements thereon, consisting of
an office building containing approximately 100,000 square feet ("Tenant's
Building") and all fixtures and accessory improvements thereon, including all
roadway, parking areas and landscaped areas located thereon (collectively such
Tenant's Building, fixtures and improvements are hereinafter referred to as the
"Improvements") together with all easements, rights, privileges and amenities
otherwise appurtenant to such real property (herein all collectively called the
"Premises"). The improvements are indicated upon the site plan attached hereto
as Exhibit B (the "Site Plan").

                                  ARTICLE III
                              Term and Extensions

          3.01 Initial Term. The initial term ("Initial Term") of this Lease
shall commence on the Rent Commencement Date. The Initial Term shall end ten
(10) complete Lease Years following the Rent Commencement Date.

          3.02 Lease Year. The first Lease Year during the Term shall be the
approximately twelve (12) calendar month period commencing on the Rent
Commencement Date and terminating on either (a) the day before the first
anniversary of the Rent Commencement Date if the Rent Commencement Date is the
first day of month, or (b) the last day of the twelfth (12th) full calendar
month following the Rent Commencement Date if the Rent Commencement Date is not
the first day of the month. Each subsequent Lease Year during the Term shall
commence on the day immediately following the last day of the preceding Lease
Year and shall continue for a period of twelve (12) full calendar months.

          3.03 Extensions. Provided that Tenant is not in default of this Lease,
at the time of expiration of the then-existing Term of this Lease and provided
that the term has not ended, Landlord hereby grants to Tenant the option to
extend the Term for two (2) additional periods of five (5) years each upon the
terms and conditions contained herein, each exercisable by Tenant's written
notice to Landlord of such exercise given not less than twelve (12) months prior
to the expiration of the Initial Term hereof, or of the then existing option
period, as the case may be, on the same terms and conditions as applied during
the Initial Term except the base rent shall be $11.50 per square foot, with
3% escalations every year. The initial option to extend after the initial lease
term subject to increased lease rate of $11.50 per square
<PAGE>

foot with 3% annual escalations every year. Any extension after the initial
option period shall be at the then prevailing market rate. The extension periods
shall be each exercisable by Tenant's written notice to the Landlord of such
exercise given not less than twelve (12) months prior to the expiration of the
initial term or of the existing option period as the case may be on the same
conditions as applied during the Initial Term. An allowance in the amount of
$6.00 per square foot for the office space and $3.00 per square foot for the
production area is included in the initial extension period lease rate and shall
be paid to reimburse Tenant for alterations made by Tenant in compliance with
the requirements of Article IX of this Lease. Should Tenant fail to exercise any
prior extension option offered hereunder, all subsequent extension options shall
be deemed waived as well. Tenant shall have no other renewal rights hereunder.
The Initial Term of this Lease, plus all options to extend validly exercised by
Tenant as provided in this Article III, are herein collectively referred to as
the "Term".

          3.04 Rent Commencement Date. As used herein the term "Rent
Commencement Date" shall have the meaning ascribed to such term in the Agreement
to Lease entered into between Landlord and Tenant as of the date hereof.

          3.05 Rent Commencement Date Agreement. When the Rent Commencement Date
has been determined, Landlord and Tenant shall execute a memorandum which shall
expressly confirm or revise the Base Rent, Rent Commencement Date, Lease Year,
the expiration date of the Initial Term, that construction of the Premises has
been completed and possession accepted by Tenant and which shall ratify and
affirm all of the terms and provisions of this Lease.


                                   ARTICLE IV
                                      Rent

          4.01 Base Rent. Tenant shall pay to Landlord as Base Rent on the
Premises, on the first day of each month in advance, during the Term of this
Lease and any extensions hereof, as follows:

          (a)  Commencing on the Rent Commencement Date of this Lease and
     terminating on the last day of the second (2nd) Lease Year hereunder, an
     annual Base Rent of Seven Hundred Seventeen Thousand and 00/100 Dollars
     ($717,000.00) payable in equal monthly installments of Fifty-nine thousand
     Seven Hundred fifty and 00/100 Dollars ($59,750.00);

          (b)  Commencing on the first day of the third (3rd) Lease Year and
     terminating on the last day of the fourth (4th) Lease Year hereunder, an
     annual Base Rent of Seven Hundred Forty-four Thousand and 00/100 Dollars
     ($744,000.00) payable in equal monthly installments of Sixty-two Thousand
     and 00/100 Dollars ($62,000.00);

          (c)  Commencing on the first day of the fifth (5th) Lease Year and
     terminating on the last day of the sixth (6 th) Lease Year hereunder, an
     annual Base Rent of Seven Hundred Seventy thousand and 00/100 Dollars
     ($770,000.00) payable in equal monthly installments Sixty-four Thousand One
     Hundred Sixty-six and 67/100 Dollars ($64,166.67);

          (d)  Commencing on the first day of the seventh (7 th) Lease Year and
     terminating on the last day of the eighth (8 th) Lease Year hereunder, an
     annual Base Rent of Seven Hundred Ninety-five Thousand and 00/100 Dollars
     ($795,000.00) payable in equal monthly installments of Sixty-six Thousand
     Two Hundred Fifty and 00/100 Dollars ($66,250.00);
<PAGE>

          (e)  Commencing on the first day of the ninth (9 th) Lease Year and
     terminating on the last day of the tenth (10 th) Lease Year hereunder, an
     annual Base Rent of Eight Hundred Twenty-four Thousand and 00/100 Dollars
     ($824,000.00) payable in equal monthly installments of Sixty-eight Thousand
     Six Hundred Sixty-six and 67/100 Dollars ($68,666.67).

This Section 4.01 shall be amended in the manner provided in the Agreement to
Lease to reflect any change in the Base Rent in the event the actual cost of the
project varies upward or downward from the anticipated cost of the project.

          4.02   Partial Month Rent. If the Rent Commencement Date or the date
upon which the Term expires shall be other than the first or last day of a
calendar month, as the case may be, Base Rent shall be pro-rated for the period
by taking the amount of monthly Base Rent divided by 30 and multiplying that
amount times the number of days of such partial month.


          4.03   Terms of Payment. All Rent and other payments to be made by
Tenant to Landlord hereunder shall be made payable to Landlord in current legal
tender of the United States of America and sent to Landlord at the place to
which notice to Landlord is required to be sent hereunder unless Landlord shall
direct otherwise by notice to Tenant. Extensions, indulgences, or changes by
Landlord upon any occasion in the mode or time of payment of rent or any other
payment to be made by Tenant to Landlord hereunder shall not be construed as any
continuing waiver or change, or as requiring or allowing in the future any
similar change or indulgence. All rent shall be payable as stated without
notice, demand, setoff, or abatement.

          4.04   Additional Rent. All amounts other than Base Rent which Tenant
is required to pay or discharge pursuant to this Lease including, but not
limited to, charges for taxes, insurance. utilities, and any penalties for late
payment of Base Rent shall constitute Additional Rent.

          4.05   Rent. The term "Rent" shall mean all amounts due as Base Rent
and all other sums payable by Tenant to Landlord hereunder.

                                   ARTICLE V
                               Absolute Net Lease

It is the purpose and intent of Landlord and Tenant that the rent herein above
provided to be paid to Landlord by Tenant be absolutely net to Landlord so that
this Lease shall yield net to Landlord without abatement, set-off or deduction
therefrom the rent as herein above provided, to be paid during the Term of this
Lease or any extensions hereof, and, that all costs, expenses, and impositions
of every kind or nature whatsoever relating to the Premises, the use thereof,
the maintenance thereof, the operation thereof, the management thereof, or
otherwise which may arise or become due during the Term of this Lease or any
extensions hereof be paid by Tenant, and Landlord be indemnified and saved
harmless by Tenant from and against the same. Tenant hereby assumes and agrees
to perform all duties and obligations with relation to the Premises, as well as
the use, operation, management, and maintenance thereof even though such duties
and obligations would otherwise be construed to be those of the Landlord.
Nothing herein contained, however, shall be deemed to require Tenant to pay or
discharge any liens or mortgages of any character, whatever which may be placed
upon the Premises by the affirmative act of Landlord. Except as expressly set
forth in this Lease, this Lease shall not terminate, nor shall Tenant have any
right to terminate this Lease for any cause whatsoever, any present or future
law to the contrary notwithstanding. Tenant agrees that it will remain obligated
under this Lease in accordance with its terms notwithstanding any action,
<PAGE>

which may be taken with respect to this Lease by any trustee or receiver of
Landlord in any bankruptcy or similar proceeding.

                                   ARTICLE VI
                                      Use

The Premises shall be occupied and used by Tenant for the purpose of conducting
therein the business of office and light manufacturing. Tenant shall use and
occupy the Premises in accordance with all governmental laws, statutes, orders,
ordinances, rules and regulations of any governmental authority with
jurisdiction affecting the Premises from time to time, including, without
limitation, applicable zoning ordinances. Tenant agrees to comply with all deed
restrictions, declarations, conditions and covenants applicable to the Premises
as of the date of this Lease, if any, and to which the Premises or Lease is
later made subject with Tenant's written consent and to assume and perform any
duties or obligations thereunder applicable to the Premises or to the owner of
the Premises. Tenant shall not use, or allow the Premises to be used, for any
purpose other than as specified herein and shall not use or permit the Premises
to be used for any unlawful, disreputable or immoral purpose or in any way that
will injure the reputation of the Premises, detract from its value, or in
violation of any certificate of occupancy applicable to the Premises, or
endanger the Premises or unnecessarily increase the applicable insurance
premiums payable with respect thereto, or create a nuisance, or permit the
Premises to be occupied in whole or in part by any other person, except as
otherwise provided herein.

Landlord shall not allow any buildings to be constructed on Landlord's property
adjacent to Tenant's Premises which obstruct the free and clear view of Tenant's
south facing antennas. Tenant requires look angles for antennas which are due
south 30 degrees with an elevation of not less than 30 degrees. Any views above
30 degrees shall not be obstructed by building or objects Landlord places
adjacent to the Premises.

Landlord shall submit any plans of any building to be constructed on Landlord's
property adjacent to Tenant's Premises for Tenant's review to assess how it
affects Tenant's antennas. If Tenant determines in Tenant's reasonable
discretion under the above criteria that Tenant's antennas are obstructed and so
notifies Landlord in writing within ten (10) days of Landlord's notice to
Tenant, then Landlord shall modify the location or characteristics of the
proposed building until Tenant's antennas are not affected. If Tenant's antennas
are obstructed in any way during the term of this Lease, in violation of this
section, then it will be the sole cost and responsibility of Landlord to
relocate Tenant's antenna pad site to a site reasonably agreeable to Tenant. If
Landlord does not do so within ten (10) days of written notice from Tenant, then
Tenant may terminate the Lease upon 120 days written notification given within
ten (10) days of Landlord's failure to do so.

This entire Article shall be made a part of the covenants for all of the
adjacent land that is being purchased by Cherokee Equities from ITT, generally
known as 1500 Garden of the Gods Road. Should Cherokee Equities sell any of such
adjacent land and at any time after the execution of this Lease, then the
provisions under this Article shall be binding upon the purchasers and the
successors and assigns of Cherokee Equities thereafter, for so long as the
Stanford Telecommunications' Lease is in effect.

Cherokee Equities shall provide legal access to either Garden of the Gods Road
or Centennial Boulevard.
<PAGE>

                                  ARTICLE VII
                           Subletting and Assignment

          7.01   Subletting and Assignment. Tenant shall not assign this Lease
or sublet all or any part of the Premises without the prior written consent of
Landlord which consent shall not be unreasonably withheld. In the event of any
assignment or subletting, Tenant shall nevertheless at all times remain fully
responsible and liable for the payment of Rent and for compliance with all of
its other obligations under the terms, provisions and covenants of this Lease
unless relieved therefrom in writing by Landlord, and Tenant's Assignee and/or
Subleasee shall assume in writing and agree to keep and perform all of the terms
of this Lease on the part of Tenant to be kept and performed and shall be and
become jointly and severally liable with Tenant for the keeping and performing
thereof In addition, Tenant shall have the right, by prior written notice to
Landlord, to transfer and assign this Lease without Landlord's consent to any
parent, subsidiary or affiliated company of Tenant, with Tenant remaining liable
for the performance of the terms of this Lease and a copy of any such assignment
or sublease and an executed assumption agreement shall be delivered to Landlord
at the time of any assignment or sublet. For purposes of this Article, a
leasehold mortgage shall be deemed an assignment.

          7.02   Limits on Assignees. Notwithstanding anything to the contrary
contained in this Lease, Tenant shall not, without the prior written consent of
Landlord (which Landlord shall not reasonably withhold and which consent, in
each instance to be effective, must expressly state Landlord is aware that the
subject assignee or subtenant, as the case may be, is a tax-exempt entity)
assign all or any part of its interest in this Lease or sublet all or any part
of the Premises, or in any other manner grant any right to use, occupy or
otherwise "lease" (within the meaning of Internal Revenue Code of 1986, Section
168(h), as amended ("Section 168(h)")) all or any part of the Premises, to any
"tax-exempt entity," as defined in Section 168(h), to the extent that the
aggregate portion of the Premises sublet, assigned, used, occupied or "leased"
by all such tax-exempt entities shall not be more than 35% of the Premises.
Tenant agrees that any assignment of lease or subletting made in violation of
the foregoing sentence will be deemed initially void, and acknowledges that,
notwithstanding such voiding, Landlord may incur damages as a result of such
violations, and Tenant agrees to indemnify Landlord from any such damages.

          7.03   Assignment by Landlord. Landlord shall have the right to
transfer all or any part of Landlord's interest in the Lease and the Premises
without the consent or approval of Tenant and without notice to Tenant, which
transfer shall work an absolute release of Landlord's liabilities and
obligations hereunder arising after the date of such assignment, providing all
obligations of Landlord hereunder arising after the date of such assignment are
assumed by the assignee.

                                  ARTICLE VIII
                      Quiet Enjoyment - Landlord's Warrant

Landlord covenants and agrees with Tenant that so long as Tenant keeps and
performs all of the covenants and conditions to be kept and performed by Tenant
hereunder, Tenant shall have quiet, undisturbed and continued possession of the
Premises free from any claims by any persons claiming under, by or through
Landlord and its assigns.

                                   ARTICLE IX
                                  Alterations

          9.01   Tenant's Alterations. Tenant shall have the right, at its sole
cost and expense, at the commencement of and during the term of this Lease or
any extension thereof to make such alterations in
<PAGE>

and/or additions to the Premises, including without limiting the generality of
the foregoing, alterations in the water, gas and electrical wiring systems as
may be necessary to fit the same for Tenant's business, upon first delivering to
Landlord written plans and specifications for all such work and obtaining the
written approval of Landlord as to said plans and specifications and the
contractor(s) to perform such work, such approval not to be unreasonably
withheld or delayed, financial assurances, the materials to be used and the
manner of making such alterations and/or additions. Tenant shall be able to make
any additions and/or alterations necessary for his business without prior
written consent of Landlord if the total sum of those alterations and/or
additions amounts to less than $25,000.00.

          Upon the termination of this Lease, Tenant shall not be required to
remove any of the original Improvements still in existence or any such approved
subsequent alterations or improvements (unless otherwise required in Landlord's
written approval), or to restore (unless otherwise required in Landlord's
written approval) the Premises to its original condition. All such Improvements
and alterations (excluding Tenant's Property as defined in Article X) now or
hereafter located on the Premises are the Property of Landlord.

          9.02   Method of Alterations. All alterations, additions and
improvements made by Tenant shall be done in a good and workmanlike manner
without impairing the structural soundness of the Premises, penetrating the
roof, and without lessening the value thereof. All such work shall be performed
in accordance with all applicable laws, ordinances, rules, and regulations and
requirements of all governmental authorities having jurisdiction over the
Premises. Before commencing any work, Tenant shall obtain or cause to be
obtained, workers' compensation and employer's liability insurance covering all
persons employed in connection with the work and with respect to whom death or
bodily injury claims could be asserted against Landlord and/or Tenant, and
general liability insurance insuring Landlord and Tenant against any liability
that may be incurred as a result of any work done by Tenant in, to or upon the
Premises. A certificate of insurance or copy of said policy shall be delivered
to Landlord upon written request. Tenant shall procure and pay for all permits,
licenses and authorizations required in connection with any such alteration,
addition or improvement, and Landlord agrees to cooperate with Tenant, at
Tenant's expense, in procuring such permits, licenses and authorizations.

                                   ARTICLE X
                               Tenant's Property

          10.01   Installation. Removal. Tenant may, at its sole cost and
expense, install any trade fixtures, equipment, and other personal property of a
temporary or permanent nature used in connection with its business on the
Premises ("Tenant's Property"), and Tenant shall have the right at any time
during the Term of this Lease or any extensions hereof or prior to expiration or
earlier termination of the Lease or any extensions hereof, provided Tenant is
not in default of any of the terms of this Lease, to remove any and all such
trade fixtures, equipment, and other personal property that it may have stored
or installed upon the Premises; provided, however, that Tenant shall have no
right to remove any item which is necessary for the operation or maintenance of
the Premises as such, without regard to the nature of the business conducted
therein; and provided, further, that in the event of such removal, Tenant shall
repair any damage caused by the removal of such trade fixtures, equipment, and
other personal property and restore the Premises substantially to the same
condition, ordinary wear and tear excepted, in which they were at the time
Tenant took possession.

          10.02   Required Removal. In case Tenant shall decide not to remove
any part of its Tenant's Property prior to expiration or earlier termination of
this Lease, Tenant shall notify Landlord in writing not fewer than ninety (90)
days prior to the expiration of the Term of this Lease or any extensions
<PAGE>

hereof, specifying those items of Tenant's Property that Tenant has decided not
to remove. If, within thirty (30) days after service of such notice, Landlord
shall request Tenant to remove any of said Tenant's Property, Tenant shall, at
its own expense, before the expiration of the Term of this Lease or any
extension hereof, remove said Tenant's Property and, in case of damage by reason
of such removal, restore the Premises to good order and condition. Tenant will
pay all costs and expenses incurred by Landlord in removing, sorting, or
disposing of Tenant's Property and repairing all damage to the Premises caused
by removal of Tenant's Property which Tenant has failed to remove despite the
requirements of this section (10.02). Any of Tenant's Property not removed by
Tenant upon the expiration or earlier termination of this Lease or any
extensions hereof shall be considered abandoned by Tenant and may be
appropriated, sold, destroyed, or otherwise disposed of by Landlord without
liability or obligation on Landlord's part, to and without any obligation to
care for or account for same.

          10.03   Title at Termination. As to the Tenant's Property that Tenant
has not elected to remove pursuant to Section 10.01 or that Tenant is not
required to remove pursuant to Section 10.02, at the expiration or earlier
termination of this Lease or any extensions hereof, all remaining Tenant's
Property shall, at Landlord's sole election, become and remain the property of
Landlord, free and clear of any claim or interest of Tenant or anyone claiming
thereunder. At the request of Landlord, Tenant will, at such time, execute,
acknowledge, and deliver to Landlord a bill of sale or other appropriate
conveyance document evidencing the transfer to Landlord of all right, title and
interest of Tenant in and to all or any part of the remaining Tenant's Property.

                                   ARTICLE XI
                              Lien or Encumbrance

          11.01   No Liens. Tenant will pay or cause to be paid all charges for
all work done, including without limitation all labor and materials for all
repairs, alterations, and additions, to or upon the Premises during the Term of
this Lease or any extensions hereof and will not suffer or permit any
mechanic's, materialman's, or similar liens for labor or materials furnished to
the Premises prior to or during the Term of this Lease or any extensions hereof
to be filed against the Premises prior to or and if any such lien shall be
filed, Tenant will either pay the same or procure the discharge thereof by
giving security or in such other manner as may be required or permitted by law
within thirty (30) days after such filing or within such shorter time period as
may be required by law. Tenant shall have the right, however, at its sole cost
and expense, in its name or in the name of Landlord or in the name of both, to
contest any such lien, provided the existence of such lien pending such contest
shall not jeopardize Landlord's interest in the Premises. Tenant shall indemnify
Landlord against, and save Landlord harmless from, any and all loss, damage,
claims, liabilities, judgments, interest, costs, expenses, and attorney's fees
arising out of the filing of any such lien.

          11.02   No Consent to Work, Lien or Encumbrance. Nothing contained
herein shall constitute any consent or request by Landlord, express or implied,
to or for the performance of any labor or services or the furnishing of any
materials or other property in respect of the Premises nor as giving Tenant any
right, power, or authority to contract for or permit the performance of any
labor or services or the furnishing of any materials or other property in such
fashion as would permit the making of any claim against Landlord or the Premises
in respect thereto. Nothing in this Lease shall be construed as empowering
Tenant to encumber or cause to be encumbered the title or interest of Landlord
in the Premises in any manner whatsoever. Landlord shall be permitted to post
the Premises with Landlord's notice of non-liability.
<PAGE>

                                  ARTICLE XII
                            Repairs and Maintenance

          12.01   Duty to Repair. During the Term of the Lease Tenant shall, at
its sole cost and expense, keep the Premises and the adjoining sidewalks, curbs,
and passageways, if required by governmental authority, free from unlawful
obstructions, and will keep the Premises in as good condition and repair as they
were upon commencement of the Term of this Lease, normal wear and tear excepted,
and will perform all maintenance and make all necessary repairs thereto,
interior and exterior, structural and non-structural, ordinary and
extraordinary, and foreseen and unforeseen, including but not limited to
maintenance and repair of the plumbing, electrical wiring, air conditioning and
heating equipment, walls, foundations, services, roof, doors, floors,
maintenance and repair of the parking area, painting of the walls of the
Improvements, and repair of all glass and casualty damage. For all such work
with a cost in excess of $10,000, Tenant shall, prior to making any repair,
deliver to Landlord written plans and specifications for all such work and
obtain the written approval of Landlord as to the contractor(s) to perform such
work, financial assurances, materials to be used and the manner of making such
repairs. Landlord shall not unreasonably withhold or delay its approval of said
repairs proposed to be made by Tenant.

          12.02   Definition and Standard of Repair. The term "repairs" shall
include all necessary replacements, renewals, alterations, additions, and
betterments. The necessity for and adequacy of repairs to the Improvements shall
be measured by the standard which is appropriate for buildings of similar
construction and class, provided that Tenant shall in any event make all repairs
necessary to avoid any structural damage or injury to any of the Improvements.
All repairs made by Tenant shall be equal or better in quality and class to the
original work shall meet the same requirements as are set out in Article 9.02 of
this Lease to the extent necessary and shall be made in a good and workmanlike
manner and in compliance with all applicable permits and authorizations and
building and zoning laws and with all other laws, rules, regulations, and
ordinances governing such work. Tenant will not commit any waste of the
Premises.

          12.03   No Obligation to Repair. Landlord shall not under any
circumstances be required to furnish any services or facilities or to make any
maintenance repairs, replacements or alterations of any nature or description in
or to the Premises whether ordinary or extraordinary, structural or non-
structural, foreseen or unforeseen, or to make any expenditure whatsoever in
connection with this Lease or to maintain the Premises in any way. Tenant hereby
waives the right to make repairs at the expense of Landlord pursuant to any law
in effect at the time of the execution of this Lease or thereafter enacted, and
assumes the full and sole responsibility for the condition, operation, repair,
replacement, maintenance, and management of the Premises. Landlord covenants to
cooperate with Tenant in processing claims with respect to matters covered by
available insurance.

                                  ARTICLE XIII
                              Requirements of Law

          Tenant shall, at its expense, comply with, or cause to be complied
with, all insurance requirements, and all current and future laws, statutes,
ordinances and regulations of federal, state, county and, municipal authorities
including, but not limited to, the Americans With Disabilities Act
(collectively, "Laws") and any restrictions, declarations, conditions,
agreements, covenants or requirements, if any, applicable to the Premises as of
the date of this Lease or to which the Premises or this Lease is later made
subject with Tenant's consent, which shall impose any duty or obligation with
respect to the Premises or the Landlord including, but not limited to, a duty to
construct additional improvements or modify the Improvements or with respect to
the conduct of Tenant's business therein. Tenant shall have the right at
Tenant's own expense, to object to and appeal from any administrative or
judicial decision requiring
<PAGE>

compliance and Landlord shall cooperate at Tenant's expense with any such appeal
and/or objection by Tenant. In the event compliance shall require improvements
or alterations to the Premises, then Tenant shall, at Tenant's sole expense,
construct such improvements or alterations in accordance with the provisions for
Tenant's alterations contained in Article IX of this Lease.

                                  ARTICLE XIV
                             Damage or Destruction

          14.01   Tenant's Obligation to Rebuild. Except in the event
oftermination as permitted hereinafter in this Article XIV, Tenant shall repair
and rebuild the Premises in the event of damage to or destruction of the
Improvements during the Term of this Lease by fire, the elements, or other
casualty. The proceeds of the insurance carried pursuant to Article 15 of this
Lease entitled "Insurance" and any additional Tenant funds reasonably required
by Landlord shall be paid into an escrow account with Landlord's first mortgage
lender or a bank selected by Landlord and reasonably agreed to by Tenant. The
insurance proceeds and other funds of Tenant shall be used by Tenant for the
prompt reconstruction or repair, as the case may be, of the Improvements. Tenant
shall rebuild or repair the same in such manner that the Improvements as so
rebuilt or repaired shall be of the same or better quality and value as they
were prior to such damage or destruction, and shall have same rebuilt or
repaired and ready for occupancy within twelve (12) months from the time and
loss or destruction occurred, subject to Force Majeure. If the insurance
proceeds exceed the cost of repair or restoration, Tenant shall receive said
excess upon completion of such repair or restoration.

          14.02  Approval of Plans and Specifications. In the event of a loss
hereunder, Tenant shall submit to Landlord the plans and specification for
reconstruction or repair for Landlord's approval. Landlord shall have a fifteen
(15) day period within which to review and approve or disapprove the plans and
specifications, the contractor(s) to perform such work, materials to be used and
the manner of making such repairs.

          14.03   Payment from Escrow. Amounts shall be paid out from said
escrow account established pursuant to Section 14.01 from time to time upon the
certification of Tenant's architect that said amount is being applied to the
payment of the reconstruction or repair at a reasonable cost therefor and that
the disbursement then requested, plus all previous disbursements and the amount
of any applicable "deductible" do not exceed the cost of the repair or
restoration already completed and paid for, and that the balance in said escrow
account is sufficient to pay for the estimated cost of completing the repair or
restoration. If the insurance proceeds shall be less than the cost of repair or
restoration, Tenant shall pay the excess cost.

          14.04   Failure to Reconstruct; Termination. In case of Tenant's
failure to enter into the reconstruction or repair of the Improvements within
six (6) months from the date of payment of such insurance proceeds, or to
prosecute said reconstruction or repair with such dispatch as may be necessary
to complete the same within twelve (12) months after the occurrence of such
damage or destruction or to complete same within said twelve (12) months, then
the amount so collected, or the balance thereof remaining in the escrow account
may be requested by Landlord, in its sole discretion, and then shall be paid to
Landlord and Landlord shall after receipt of such balance terminate the Lease
and retain such amounts as liquidated damages resulting from Tenant's failure
hereunder. Tenant shall have the right to terminate the Term if less than two
(2) years remain in the Term at the time of any such casualty, and in such event
Tenant shall have no obligation to rebuild the Improvements, Landlord shall have
the sole and exclusive right to adjust the loss with the insurance carriers and
all insurance proceeds shall be paid to and retained by Landlord.
<PAGE>

          14.05   Force Majeure. "Force Majeure" shall mean events beyond the
control of the parties, including, without limitation, fire, flood, tornado, or
earthquake, war, riot, insurrection, strike, lockout, boycott or embargo, acts
of God, unavoidable casualties, labor disputes, and unusual delays in
transportation, unavailability of materials, adverse weather conditions not
reasonably anticipatable. Any party who asserts the occurrence of force majeure
shall give written notice within five (5) working days after the commencement of
a delay caused by an event of force majeure, and any party making claim therefor
shall give a supplemental notice of the period of time such delay caused by an
event of force majeure is expected to last; otherwise, any right of claim
therefor shall be deemed waived.

          14.06   No Abatement of Rent. Notwithstanding any contrary law, rent
shall not be suspended or abated as a result of such damage or destruction, and
restoration or rebuilding.

          14.07   Default in Payment of Rent. If, at any time after such
insurance proceeds come into possession of Tenant or are placed in escrow
pursuant to this Article after destruction or damage by casualty, Tenant is in
default of any rent or other charges payable under this Lease, then Landlord
shall be entitled to so much of said proceeds as may be necessary to pay and
discharge any such Rent or other charges of which Tenant is in default, whenever
and as often as any such default shall occur. Tenant shall forthwith reimburse
such escrow account by depositing therein any amount so paid out on account of
Tenant's default. Nothing herein contained, however, shall be construed as
permitting Tenant to default in the payment of Rent or other charges herein
stipulated to be paid or in the performance of any other covenants of this
Lease, and Landlord may, at its option proceed against Tenant for the collection
of such Rent or other charges in default and recover and take possession of the
Premises in accordance with the provisions of this Lease without prejudice to
Landlord's right to the benefit of such insurance money as security for Tenant's
performance under the terms of this Lease.

          14.08   Landlord's Mortgage. All provisions herein contained relative
to the disposition of payments from insurance companies are subject to the
requirement that, if any mortgagee who holds a mortgage on the Premises elects,
in accordance with the terms of such mortgage, to require such insurance
proceeds be paid to the mortgagee on account of the mortgage, then such payment
shall be made, but in such event landlord shall provide such amount as is
necessary to provide replacement funds in the manner set forth in this Article
to assure and complete the payment for the work of reconstruction or repair.

          14.09   Untenantability. Except as otherwise expressly provided in
this Lease, the untenantability or unusability of the Premises shall not
relieve, abate, or reduce Tenant's obligations under this Lease.

                                   ARTICLE XV
                                   Insurance

          15.01   Landlord's Property Insurance. Landlord shall, throughout the
Term of this Lease, at Tenant's sole cost and expense, provide and keep in force
for the benefit of Landlord and Tenant, insurance against loss or destruction of
or damage or injury to any Improvements now or hereafter erected on the Premises
resulting from fire or from any hazard included in the so-called extended
coverage endorsement (including plate glass insurance, increased cost of
construction endorsement, sprinkler leakage, collapse and vandalism and
malicious mischief, also known as "All Risks of Physical Loss" coverage). In
addition to the foregoing, Landlord shall, at Tenant's sole cost and expense,
provide and keep in force for the benefit of Landlord and Tenant, throughout the
Term of this Lease, flood insurance, provided the Premises are located within
the "Federal Flood Plain Area" of the United States, as well as
<PAGE>

insurance against loss or damage or injury or destruction of any Improvements
now or hereafter erected on the Premises resulting from water or earthquake
damage. Landlord shall provide and keep in full force all such insurance in an
amount sufficient to prevent Landlord or Tenant from becoming a co-insurer under
the terms of the applicable policy, but in no event less than the full
replacement cost of the Improvements. Such replacement cost shall be determined
annually by a method required by the insurer(s). The deductible under each of
said policies shall be an amount not greater than Ten Thousand Dollars
($10,000.00). Such insurance policies to be provided for and kept in force by
Landlord shall provide that the loss, if any, be payable to Landlord and Tenant,
as their respective interests may appear, except as herein provided, and such
insurance policies may exclude foundations, excavation and the usual items
customarily excluded in such insurance policies, and that the proceeds thereof
shall be used to repair or replace the damage sustained by the casualty.
Landlord may provide that the interest of any mortgagee under a fee mortgage
covering the Premises, be protected by proper endorsements to any such policies
of insurance, and that duplicate originals of such policies of insurance be
delivered to such mortgagee. Tenant shall pay to Landlord, upon invoice from
Landlord, the premium for such insurance, and shall pay to Landlord monthly,
with Base Rent, one-twelfth of the premium for such insurance, plus such
additional sum as is necessary to assure sufficient escrow to pay the premiums
thereon as they become due. Such funds may be commingled by Landlord, shall not
bear interest, and shall be used by Landlord to timely pay such premiums.
Landlord shall, upon written request of Tenant, provide Tenant with evidence of
such insurance on the Premises.

          15.02   Boiler Insurance. Tenant shall provide and maintain insurance,
at Tenant's cost and expense throughout the Term of this Lease, for loss or
damage by explosion of steam boilers, pressure vessels, air conditioning systems
or similar apparatus to be now or hereafter installed on the Premises, to
the extent applicable. Said insurance shall be on a Boiler and Machinery Broad
Form Policy on a repair and replacement basis, with Use and Occupancy coverage
for at least one hundred twenty (120) days. Such policy shall name Landlord,
and/or any successor Landlord and Landlord's mortgagee as additional insureds,
as their interests may appear.

          15.03   Public Liability Insurance. During the Term, at Tenant's sole
cost and expense, Tenant shall maintain in full force and effect broad form
commercial or comprehensive general liability insurance, including blanket
contractual liability coverage specifically endorsed to provide coverage for the
obligations assumed by Tenant pursuant to the Lease against claims and liability
for personal injury, bodily injury, death or property damage occurring on, in or
about the Premises, with limits of liability of not less than Five Million
Dollars ($5,000,000.00) arising out of any one occurrence or annual aggregate.
Tenant shall cause such insurance policy or policies to name Landlord, and/or
any successor Landlord and Landlord's mortgagee as additional insureds, as their
interests may appear.

          15.04   Workers' Compensation, Employer's Liability Insurance. Tenant
shall also provide and maintain, at Tenant's sole cost and expense throughout
the Term of this Lease, workers' compensation insurance with statutory limits of
liability and employer's liability insurance with limits of liability of not
less than Five Hundred Thousand Dollars ($500,000.00) in respect of any work or
other operations done or performed on or about the Premises.

          15.05   Business Interruption. Tenant shall, during the Term of this
Lease, at its sole cost and expense, procure and maintain business interruption
(or use and occupancy) insurance including, at a minimum, coverage for rent and
other charges for which Tenant is obligated hereunder for a period of twelve
(12) months.

<PAGE>

          15.06   Insurance on Tenant's Property. It is understood and agreed
that Tenant may self-insure with respect to any damage to or destruction of
Tenant's Property.

          15.07   No Separate Insurance. Tenant shall not take out separate
insurance concurrent in form or contributing in the event of loss with that
required herein to be furnished by Tenant unless Landlord is included therein as
additional insured, and as loss payee with loss payable as set out herein.
Tenant shall immediately notify Landlord in writing whenever any such separate
insurance is taken out and shall deliver the policy or policies or duplicates
thereof, or certificates evidencing the same, as provided herein.

          15.08   Conduct of Business. Cooperation. Tenant shall comply with all
requirements of said insurance policies and shall not conduct or allow to be
conducted business or other activities or fail to maintain or take other actions
with regard to the Premises in such a manner as will result in an increase in
said premiums, or a decrease in the recovery thereunder, or cancellation thereof
Any insurance proceeds payable by reason of any insured loss pursuant to or this
Article XV shall, subject to the rights of the holders of any Landlord's
mortgage upon the Premises be used exclusively for the purpose of restoring and
rebuilding the Premises. Subject to the foregoing and provided Tenant is not in
default of this Lease, Tenant shall have the sole right to adjust with the
insurance carriers (other than Landlord's Property Insurance) the amount of the
loss upon any such policies (but with prior notice to Landlord). Landlord and
Tenant shall, at Tenant's cost and expense, cooperate fully in order to obtain
the largest possible insurance recovery and shall execute any and all consents
and other instruments and take all other actions necessary or desirable in order
to effectuate the same and to cause such proceeds to be paid. In the event of a
default by Tenant or of a termination pursuant to the provisions of this Lease,
Landlord shall have the right to adjust the amount of the loss with the
insurance carriers. Landlord shall give notice to Tenant if Landlord elects to
adjust the loss as provided in this Article. If Landlord requests, Tenant shall
adjust any and all such claims and Landlord and its mortgage lender, if any,
shall have the right to join with Tenant therein.

          15.09    Requirements of Policies.

                   (a)   All policies required to be carried pursuant to this
                         Article XV:

                         (i)    shall be written and signed by solvent and
                                responsible insurance companies authorized to do
                                business in the jurisdiction wherein the
                                Premises are located having a rating of not less
                                than Best A+, Class XV;

                         (ii)   shall contain an agreement by the insurer that
                                such policy or policies shall not be canceled or
                                non-renewed without at least thirty (30) days
                                prior written notice to Landlord, Landlord's
                                Mortgage, and Tenant;

                         (iii)  may be carried under so-called blanket policies,
                                provided that the protection afforded thereunder
                                as to the Premises shall be not less than that
                                which would have been afforded under separate
                                policy or policies relating only to the Premises
                                and provided, however, any such policy of
                                blanket insurance shall specify therein, or
                                Tenant shall furnish Landlord a written
                                statement from the insurer under such policy so
                                specifying, the amount of the total insurance
<PAGE>

                                allocated to the Premises, which amount shall be
                                not less than the amount required herein and any
                                such policy shall comply in all respects with
                                the requirements set out in this Article;

                         (iv)   may be carried under a combination of primary
                                insurance and umbrella coverage; and

                         (v)    shall be primary insurance by the party
                                obligated under Article XV, which will not call
                                upon any other insurance effected or procured by
                                the other party for defense, contribution or
                                payment.

          (b) Tenant retains full responsibility for payment of all deductibles
     under each policy provided for hereunder.

          (c) Annually, Tenant will promptly furnish certificates evidencing
     that the insurance required pursuant to this Article XV is in full force
     and effect. If the certificates of insurance do not provide for thirty (30)
     days prior written notice of cancellation or non-renewal to Landlord and
     Landlord's mortgagee, Tenant shall no later than twenty (20) days prior to
     termination by cancellation or non-renewal provide to Landlord and its
     mortgagee paid receipts evidencing continuation or renewal of insurance.

          (d) If Tenant shall fail or refuse to effect or maintain any of said
     insurance, Landlord may, but shall have no obligation to do so, effect or
     maintain said insurance and the amount of money so paid, with interest at
     the Prime Rate, shall be payable by Tenant to Landlord as Additional Rent
     immediately due and payable hereunder upon notice from Landlord.

     15.10   Release Waiver of Subrogation. To the extent of available
insurance, and to the extent of insurance coverage that is required to be, but
was not, obtained under the provisions of this Lease, the parties hereby release
each other and their respective officers, directors, employees and agents from
liability or responsibility for any loss or damage in, about or to the Premises
(including, without limitation, loss or damage to personal property, and loss
arising from any act or neglect of covenants or other occupants of the Premises)
and this release shall apply notwithstanding the fault or negligence of either
party or anyone for whom a party may be responsible. The aforesaid policy shall
contain an endorsement recognizing this release and waiving all rights of
subrogation by the respective property and liability insurance carriers, if such
is reasonably available.

                                  ARTICLE XVI
                          Indemnification of Landlord

Tenant will defend, indemnify, and hold harmless Landlord from and against any
and all liabilities, claims, losses, damages, actions, judgments, costs, and
expenses (including without limitation attorney's fees and expenses) of every
kind imposed upon or asserted against Landlord or Landlord's title in the
Premises arising by reason of or in connection with (a) Tenant's possession,
use, occupancy, or control of the Premises; (b) any accident, injury to or death
of persons, or loss of or damage to property occurring on or about the Premises
or adjoining public passageways, (c) the possession, operation, use, misuse,
management, maintenance, or repair of the Premises; (d) any damage to the
environment and any property and persons injured thereby; (e) the environmental
or other condition of the Premises or (f) any failure on the part of Tenant to
perform or comply with any of the terms of this Lease. If it becomes necessary
for Landlord to defend any action seeking to impose any such liability, Tenant
will pay Landlord all costs,
<PAGE>

expenses, and attorney's fees incurred by Landlord in effecting such defense, in
addition to any other sums which Landlord may be called upon to pay by reason of
the entry of a judgment against Landlord in the litigation in which such claim
is asserted. Landlord shall not be responsible for the loss of or damage to
property or injury to or death of persons occurring in or about the Premises by
reason of any existing or future condition, defect, matter, or thing in the
Premises, or the property of which the Premises are a part, or for the acts,
omissions, or negligence of other persons or tenants in and about the Premises;
and Tenant agrees to defend, indemnify, and hold Landlord harmless from and
against all claims and liability for same. This indemnity shall not apply to any
matters caused by or arising from the negligent or willful acts or failures to
act of Landlord, or Landlord's breach of this Lease.

                                  ARTICLE XVII
                                  Condemnation

          17.01   Authority. If eminent domain proceedings are instituted by any
entity having powers of eminent domain, Landlord shall have the exclusive right
and authority to act in said proceedings, although Tenant may participate in
such proceedings at its expense as herein after so set forth if it so desires.

          17.02   Taking. Subject to the rights of Tenant hereinafter set forth,
Tenant hereby irrevocably assigns to Landlord any award or payment to which
Tenant may become entitled by reason of any taking of the Premises, or any part
thereof, in or by condemnation or other eminent domain proceedings pursuant to
any law or by reason of the temporary requisition of the use or occupancy of the
Premises or any part thereof by any governmental authority, whether same shall
be paid or payable in respect of Tenant's leasehold interest hereunder or
otherwise, but nothing in this Lease shall impair Tenant's right to any separate
award or payment on account of Tenant's trade fixtures, equipment, and other
tangible property, moving expenses, loss of business, and the like, if
available, to the extent Tenant shall have a right to a separate claim therefor
against the appropriate governmental authority, provided such separate claim or
award is not based in whole or in part upon the value of Tenant's leasehold
interest and will not diminish the award or payment to Landlord. To the extent
of such right, Tenant shall not be deemed to have assigned the same to Landlord,
and Tenant shall be entitled to participate in any such proceedings described in
this section at Tenant's sole expense.

          17.03   Termination. If all or substantially all of the Premises shall
be taken in or by such proceedings, or if Landlord shall convey all or
substantially all of the Premises under the threat of the exercise of the power
of eminent domain, and if Tenant determines in good faith and exercising
reasonable judgment that the remaining portion of Premises is no longer suitable
to operate thereon the business then being operated, Tenant shall, within sixty
(60) days after receipt of notice of any such taking, give written notice to
Landlord of its intention to terminate this Lease as of the day preceding the
date of the vesting of title to the Premises or portion thereof in the
condemning authority, and all rent and other amounts payable by Tenant hereunder
shall be apportioned as of the date of such vesting.

          17.04   Restoration. If less than all or less than substantially all
of the Premises shall be taken by condemnation or other eminent domain
proceedings, or if the use or occupancy of the Premises or any part thereof
shall be temporarily requisitioned by any governmental authority, civil or
military, then this Lease shall continue in full force and effect without
abatement or reduction of rent or other amounts payable by Tenant hereunder,
notwithstanding such taking or requisition. In the event of any such lesser
taking, Landlord shall promptly make available to Tenant out of the award,
payment, or compensation received by Landlord, and Tenant shall use said funds,
in the same manner as insurance proceeds are used to repair casualty damage
hereunder, to promptly repair any damage caused by any such taking or
<PAGE>

requisition such that, after completion of such repair, the Premises shall be as
nearly as possible in a condition as good as the condition thereof immediately
prior to such taking or requisition, ordinary wear and tear excepted, provided
that Tenant shall not be obligated to expend an amount therefor in excess of the
proceeds received by Tenant from Landlord. Any proceeds remaining hereunder
shall be retained by Landlord.

                                 ARTICLE XVIII
                                    Default

          18.01   Events of Default. Each of the following shall be deemed
                  default by Tenant:

          (a)     Tenant's failure to pay Rent when such becomes due as herein
     provided and/or any other charges or payments herein reserved, included or
     agreed to be treated or collected as Rent and/or any other charge, expense
     or cost herein agreed to be paid by Tenant, provided that Landlord shall
     have first given Tenant ten (10) days' written notice and opportunity to
     cure the same, with no cure having been made within such ten (10) day
     period notwithstanding the foregoing Landlord shall not be required to give
     notice of monetary default more than two (2) times in any twelve (12) month
     period; or

          (b)     Tenant's failure to perform, within ten (10) days after
     written notice from Landlord (or within a reasonable time thereafter if the
     default is of such a nature that it cannot be cured within such ten (10)
     day period, and Tenant does not thereafter complete the same in good faith
     and with reasonable diligence), any other terms, conditions, or covenants
     of this Lease to be observed by Tenant; or

          (c)     The adjudication of Tenant as a bankrupt or insolvent; or the
     making by Tenant of a general assignment for the benefit of creditors; or
     the appointment of a receiver in equity for the property of Tenant,
     provided such appointment is not released, bonded according to law or
     otherwise provided for by indemnity within thirty (30) days after written
     notice thereof first given to Tenant, within a reasonable time after the
     occurrence thereof; or the appointment of a trustee, custodian or receiver
     for Tenant's Property in a reorganization, arrangement or other bankruptcy
     proceeding; or Tenant's filing of a voluntary or involuntary petition in
     bankruptcy or for a bankruptcy organization, liquidation or arrangement; or
     Tenant's filing of an answer admitting bankruptcy or agreeing to a
     bankruptcy reorganization liquidation or arrangement.

          18.02   Landlord's Rights Upon Tenant's Default. In the event of any
default set forth in Article 18.01, Landlord, in addition to any other rights or
remedies it may have at law or in equity, may do any one or more of the
following:

          (a)     elect to terminate this Lease and Tenant's right to
     possession; or

          (b)     perform, on behalf and at the expense of Tenant (entering upon
     the Premises for such purpose, if necessary), any obligation of Tenant
     under this Lease which Tenant has failed to perform, the cost of which
     performance or liability by Landlord shall be deemed Additional Rent and
     incurred for the account of Tenant, and Tenant shall reimburse Landlord
     therefor or save Landlord harmless therefrom upon demand provided, however,
     that Landlord may cure any such default described in this subparagraph
     prior to the expiration of the cure period established in Section 18.01,
     but after such notice to Tenant, if the curing of such default prior to the
     expiration of said cure period. is reasonably necessary to protect the
     Premises or Landlord's interest in the
<PAGE>

     Premises, or to prevent injury or damage to persons or property.
     Notwithstanding anything to the contrary contained herein, in the case of
     emergency, notice required pursuant to this Article 18 may be given
     verbally or in any other reasonably due and sufficient manner having regard
     to the emergency and the attending circumstances. If any such notice shall
     not be given in the manner described in Article XXIII of this Lease
     entitled "Notice", then as soon thereafter as practicable, such notice
     shall be followed up by notice given in the manner prescribed in said
     Article. No entry by Landlord, in accordance with the provisions of this
     Article, shall be deemed to be an eviction of Tenant. Landlord's
     performance of any such covenant shall neither subject Landlord to
     liability for any loss, inconvenience or damage to Tenant nor be construed
     as a waiver of Tenant's default or of any other right or remedy of Landlord
     in respect of such default, or as a waiver of any covenant, term or
     condition of this Lease; or

          (c)     Using such force as may be reasonably necessary, re-enter upon
     the Premises, remove all persons and property therefrom, and dispose of
     store such property in a public warehouse or elsewhere at the sole cost and
     for the account of Tenant, all without service of notice or resort to legal
     process, without being deemed guilty of trespass or becoming liable for any
     loss or damage which may be occasioned thereby (except for any loss or
     damage resulting from or caused by the gross negligence or criminal act of
     Landlord or its employees, agents or contractors), and without such re-
     entry being deemed to terminate this Lease.

          18.03   Re-letting. In the event Landlord re-enters upon the Premises
as provided in clause (c) of the foregoing Section 18.02, or takes possession of
the Premises pursuant to legal proceedings or pursuant to any notice provided
for by law, Landlord may in addition to all other rights and remedies provided
or this Lease or at law or in equity:

          (a)     Landlord may terminate this Lease and forthwith repossess the
     Premises and remove all persons or property therefrom and be entitled to
     recover from Tenant, as damages, the sum of money equal to the total of (i)
     the reasonable cost of recovering the Premises, (ii) the accrued and unpaid
     rentals owed at the time of termination plus interest thereon from such due
     date at the lesser of the Default Rate, as hereinafter defined, or the
     maximum rate permitted by law, (iii) the discounted net present value of
     the balance of the fixed annual minimum rent for the remainder of the term,
     and (iv) any other sum of money and damages owed by Tenant to Landlord; or

          (b)     Landlord may terminate Tenant's right of possession (but not
     this Lease) and may repossess the Premises without demand or notice of any
     kind to Tenant and without terminating this Lease in which event Landlord
     may, but shall be under no obligation to do so, relet the same for the
     account of Tenant for such rent and upon such terms as shall be
     satisfactory to Landlord. For the purpose of such reletting, Landlord is
     authorized to make repairs, changes, alterations or additions to the
     Premises to make same relettable, and (i) if Landlord shall be unable to
     relet the Premises, or (ii) if the same are relet and sufficient sums shall
     not be realized from such reletting (after paying: (a) the unpaid rentals
     due under the Lease earned, but unpaid at the time of reletting plus
     interest thereon at the lesser of the Default Rate or the maximum rate
     permitted by applicable law, (b) the cost of recovering possession,
     including Landlord's attorney's fees (c) all of the costs and expenses of
     reletting including broken commissions, advertising, decorations, repairs,
     changes, alterations and additions by Landlord, and (d) the expense of the
     collection of the Rent accruing therefrom) to satisfy the rent and all
     other charges provided for in this case to be paid by Tenant then Tenant
     shall pay to Landlord, as damages, the sum equal to the amount of the Rent
     and other expenses payable by Tenant for such period or periods, or if the
     Premises have been relet, Tenant shall satisfy and pay any such deficiency
     upon demand therefor from time to time and Tenant
<PAGE>

     agrees that Landlord may file suit to recover any sums falling due under
     the terms of this Article from time to time upon one or more occasions
     without Landlord being obligated to wait until expiration of the term of
     this Lease. Such reletting shall not be construed as an election on the
     part of Landlord to terminate this Lease unless a written notice of such
     intention be given to Tenant by Landlord. Notwithstanding any such
     reletting without termination, Landlord may at any time thereafter elect to
     terminate this Lease for such previous breach. Failure of Landlord to
     declare any default immediately upon occurrence thereof or delay in taking
     any action in connection therewith shall not waive such default but
     Landlord shall have the right to declare any such default at any time
     thereafter.

          (c)     As used herein "Default Rate" shall mean the base rate on
     corporate loans at large U.S. money centers or commercial banks as
     published from time to time by the Wall Street Journal plus two hundred
     basis points (two percent (2%)) adjusted with each change in each published
     rate.

          18.04   Damages Upon Termination. In the event that Landlord at any
time terminates this Lease for any default by Tenant, in addition to any other
remedies Landlord may have, Landlord may recover from Tenant (i) all damages
Landlord may incur by reason of such default, including, without limitation, all
repossession costs, brokerage commissions, court costs, attorneys' fees,
alteration and repair costs, (ii) the accrued and unpaid rentals owed at the
time of termination plus interest thereon from such due date at the lesser of
the Default Rate or the maximum rate permitted by law, (iii) the discounted net
present value of the balance of the Rent for the remainder of the Term, and (iv)
any other sum of money and damages owed by Tenant to Landlord. All such amounts
shall be immediately due and payable from Tenant to Landlord.

                                  ARTICLE XIX
                                     Signs

Tenant shall have the right to erect, at its expense and in accordance with all
applicable laws, ordinances, rules and regulations, in or on the Premises such
sign or signs as it may desire.

                                   ARTICLE XX
                             Taxes and Other Liens

          20.01   Impositions. Tenant shall pay before any fine, penalty,
interest, or cost may be added thereto for the nonpayment thereof, all taxes
(including, without limitation, real and personal property, franchise, sales and
rent taxes), assessments and levies, ad valorem taxes, charges for water, sewer,
utility and communications services, vault charges, license and permit fees,
dues or assessments, general or special, of any association to which the
Premises is subject and other governmental levies and charges, general and
special, ordinary, and extraordinary, unforeseen as well as foreseen, of any
kind and nature (collectively "Impositions") which may be charged, assessed,
levied or imposed during the Term of this Lease upon (i) Tenant, (ii) the
Premises or any part thereof or (iii) Landlord, as a result of or arising in
respect of the acquisition, ownership, occupancy, leasing, use, possession or
sale to Tenant of the Premises, any activity conducted on the Premises, or the
Rent; provided, however, that if, by law, any Imposition is payable or at the
option of the taxpayer may be paid in installments (whether or not interest
shall accrue on the unpaid balance thereof), Tenant may pay the same (and any
accrued interest on the unpaid balance) in installments and shall be required to
pay only such installments as may become due during the Term of this Lease as
the same respectively become due and before any fine, penalty, interest, or cost
may be added thereto for nonpayment thereof; and provided further, that any
Imposition relating to a fiscal period of a taxing authority, a part of which
period is included within the Term of this Lease and a part of which is
<PAGE>

included in a period of time before the commencement of the Term or after the
termination of this Lease, other than a termination of this Lease pursuant to
Article 18, shall (whether or not such Imposition shall be assessed, levied,
confirmed, imposed, or become a lien upon the Premises or shall become payable,
during the term of this Lease) be appropriately pro rated between Landlord and
Tenant.

          20.02   Real Estate Taxes and Assessments. Notwithstanding anything
herein to the contrary, Tenant shall pay to Landlord monthly, with Base Rent,
one twelfth of the real estate taxes, assessments, and levies, and ad valorem
taxes on the Premises or any part thereof, plus such additional sum as is
necessary to assure sufficient escrow to pay same as they become due. Such funds
may be commingled by Landlord, shall not bear interest, and shall be used by
Landlord to timely pay such taxes, assessments, and levies.

          20.03   Tax on Tenant Additions. Tenant shall pay all additional taxes
levied, assessed or becoming payable on Tenant's Property or by reason of the
improvements, alterations or additions to the Premises installed by Tenant at
any time during the Term of this Lease.

          20.04   Exceptions. Nothing in this Lease shall require Tenant to pay
any corporate, estate, inheritance, succession, capital levy, stamp, transfer or
similar tax of Landlord, or any income, excess profits, franchise, revenue or
similar tax or any other tax or assessment determined on the basis of Landlord's
net income or net worth nor shall any tax, assessment, charge, or levy of the
character described in this Section 20.04 be deemed to be included within the
term "imposition"; provided, however, that if at any time under the laws of the
State or any political subdivision thereof in which the Premises is located a
future change in the method of taxation or in the taxing authority, or for any
other reason, a franchise, income, transfer, profit or other tax or governmental
imposition, however designated, shall be levied against Landlord in substitution
in whole or in part for any Imposition, or in lieu of additions to or increases
of said Impositions then said franchise, income, transfer, profit or other tax
or governmental imposition shall be deemed to be included within the term
"Imposition," and Tenant shall pay and discharge such Imposition in accordance
with Section 20.01 in respect of the payment of Impositions, to the extent it
would be payable if the Premises were the only property of Landlord subject to
such Imposition.

          20.05   Proof of Payment. Tenant agrees to submit to Landlord official
receipts evidencing payment of said Impositions at the place at which rental
payments are required to be made at least ten (10) days before said impositions
or other charges would otherwise become delinquent.

          20.06 Refunds. If Landlord shall receive a refund of any Imposition
theretofore paid by Tenant pursuant to the provisions hereof, such refund, net
of Landlord's costs of recovery, shall be promptly paid to Tenant.

          20.07 Protest. If Tenant shall, in good faith, desire to contest the
validity or amount of such Impositions, Tenant shall have the right to do so
without being in default hereunder provided that Tenant shall give Landlord
prompt written notice of Tenant's intention to institute such legal proceedings
as are appropriate, which proceedings shall be promptly instituted and conducted
in good faith and with due diligence; such proceedings shall suspend the
collection of the particular Impositions being protested, so long as the
Premises shall not be in danger of being sold, forfeited, or lost; and Tenant
shall furnish Landlord or the appropriate governmental agency with a bond made
by a surety company qualified to do business in the State in which the Premises
is located or shall pay cash to a recognized escrow agent in the County within
which the Premises is located in one and one-half (1-1/2) times the amount of
such Impositions, conditioned to pay such Impositions when the validity thereof
shall have been finally determined, which said written notice and security shall
be given by Tenant to Landlord or the appropriate
<PAGE>

governmental agency not fewer than ten (10) days before such Impositions
proposed to be contested would otherwise become delinquent. Upon the conclusion
of such contest, Landlord shall return to Tenant the security herein above
required to be deposited by Tenant, provided that Tenant shall first evidence
payment of such Impositions. Landlord may also contest the validity or amount of
any Impositions.

          20.08   Requirements of Mortgage. In the event the financing
institution where Landlord has financing on the Premises shall require Landlord
to prepay the Impositions in monthly installments of one-twelfth (1/12th) of the
annual amount thereof, then Tenant shall make to Landlord, in addition to the
Rent reserved hereunder, monthly payments of one-twelfth (1/12th) of such
Impositions.

                                  ARTICLE XXI
                                   Utilities

          21.01   Payment of Charges. Tenant shall, during the Term of this
Lease, pay and discharge punctually as and when the same shall become due and
payable without penalty all water and sewer rents, rates, and charges, charges
for removal of waste materials, and charges for water, steam, heat, gas,
electricity, light, phone, telecommunications, and power, and all other service
or services furnished to the Premises or the occupants thereof during the Term
of this Lease or any extensions hereof, and shall indemnify Landlord against any
and all liability on such account.

          21.02   Provision of Services. Landlord shall not be required to
furnish any services or facilities to the Premises and shall not be liable for
any failure of water supply or electric current or of any service by any
utility, nor for injury or damage to person (including death) or property caused
by or resulting from steam, gas, electricity, water, heat, or by rain or snow
that may flow or leak from any part of the Premises or from any pipes,
appliances, or plumbing works of the same or from the street or subsurface or
from any other place, nor for interference with light or other incorporeal
hereditaments or easements, however caused, unless due to the affirmative acts
of Landlord. Tenant hereby assumes the full and sole responsibility for the
services to and the condition, operation, repair, replacement, maintenance, and
management of the Premises.

                                  ARTICLE XXII
                            Expansion and Hold Over

          (a)     So long as at least three (3) years remain on the term
     (including any exercised extensions), Tenant, at Tenant's option, shall
     have the ability to expand up to an additional 50,000 sq. feet in an
     additional building or structure. Landlord shall reserve and control
     additional land for the term of this Lease for Tenant expansion purposes.
     Tenant shall give Landlord written notification of at least 180 days of
     Tenant's intent to expand the Premises. Landlord and Tenant shall mutually
     and diligently work together to reasonably design and build the expansion
     premises to meet Tenant's expansion needs. The design, plans and
     specifications, the contractor(s) to perform such work the materials to be
     used and the manner of making such expansion premises shall all be subject
     to Landlord's reasonable control and approval. Unless otherwise agreed to
     in writing, Tenant and Landlord shall mutually select a general contractor
     to oversee construction of the expansion premises. The general contractor
     shall bid the costs of the expansion premises to no less than 3
     subcontractors and Landlord and Tenant shall mutually agree and select the
     subcontractors to perform the work. If Landlord and Tenant cannot agree on
     selection of the general contractor or subcontractors, the lowest cost
     reasonable general contractor and subcontractors shall be selected, but
     with all risk of construction then assumed by Tenant. The initial Base Rent
     for the expansion premises shall be based on all the hard and typical and
<PAGE>

     reasonable soft costs of designing and constructing the expansion premises,
     amortized over the term of the Lease (which shall either be coterminous or
     may be reasonably extended beyond Tenant's existing Lease at Tenant's
     written option) at the cost of money (as determined by Prime as published
     in Wall Street Journal) plus a rate of return of 10%, and with periodic
     upward adjustments similar to those provided in Article IV of this Lease.

          (b)     If Tenant or anyone claiming under Tenant remains in
     possession of the Premises at the expiration of the Term, without entering
     into a written agreement with Landlord, or without having duly exercised
     its right, if any, to extend or further extend the Term, such continuing
     possession shall create a month-to-month tenancy on the terms herein
     specified, with Rent in the amount of one hundred and fifty percent (150%)
     of the immediately preceding monthly installment of Rent. Such tenancy may
     be terminated at the end of any month thereafter by either party by giving
     at least fifteen (15) days' notice thereof to the other party.

          (c)     Landlord shall grant Tenant a Right of First Opportunity to
     expand into any space which either comes available during the term of this
     Lease or Landlord constructs and is under Landlord's control in each case
     if such is within the industrial park currently known as Component Centre
     Campus, 1500 Garden of the Gods Road, Colorado Springs, Colorado. As soon
     as Landlord knows that any such space is coming available Landlord shall
     submit to Tenant written notification of the space which will be available
     and the terms on which Landlord reasonably intends to lease the space.
     Tenant shall have ten (10) business days to respond in writing of Tenant's
     election to lease the space. If Tenant so elects to lease the space, then
     the terms and conditions shall be as negotiated between the Landlord and
     Tenant but in any event not less favorable than the terms contained in
     Landlord's notice, and with the rental no less favorable than the greater
     of that contained in Landlord's notice or the rental rate determined under
     Pages 3 and 4 of this Lease, article V, Rent.

                                 ARTICLE XXIII
                                     Notice

          23.01   Notice Address. Any notice or demand which either party hereto
either is required to or may desire to serve upon the other, must be in writing,
and shall be sufficiently served if (i) personally delivered, (ii) sent by
recognized registered or certified mail, postage prepaid, or (iii) sent by
commercial overnight carrier, and addressed, in the instance of Landlord, to:

          Cherokee Equities, LLC
          5260 Mark Dabling Blvd.
          Colorado Springs, CO. 80918

          Attention: David Allen Phillips


          with a copy to:

          Sparks Dix, P.C.
          128 S. Tejon Suite 304
          Colorado Springs, CO. 80903
          Attention: Chris Brandt
<PAGE>

Or any other address which Tenant may be notified of in writing by Landlord, and
in the instance of Tenant, to:

<TABLE>
<CAPTION>
<S>               <C>                                         <C>
                  Tenant  Stanford Telecom
                          5009 Centennial Boulevard
                          Colorado Springs, CO 80919
                          Attention: Kathy Zehringer

with a copy to:                   Stanford Telecom               Stanford Telecom
                                  5009 Centennial Boulevard      Attn:   Mr. David Morrison,
                                  Colorado Springs, CO 80919     Vice President of Administration
                                                                 1221 Crossman Avenue
                                  Attention: Ernie Dickens       Sunnyvale, CA 94089-1117
</TABLE>

or such other addresses which Landlord may be notified in writing by Tenant.

          23.02   Service of Notice. Such notice shall be deemed to have been
served on the day of the mailing thereof or upon receipt in the event of
personal service or on the day of delivery of the overnight courier; provided,
however, that should such notice pertain to the change of address to either of
the parties hereto, such notice shall be deemed to have been served upon receipt
thereof by the party to whom such notice is given.

                                  ARTICLE XXIV
                                 Subordination

          24.01   Lease Subordinate. This Lease and all of Tenant's right,
title, and interest in and under this Lease shall be subject, subordinated, and
inferior to the lien of any and all ground leases, underlying leases, mortgages,
and deeds of trust and to any and all terms, conditions, provisions, extensions,
renewals or modification of any such leases, mortgages, or deeds of trust which
Landlord or any grantee or assignee of Landlord has placed or may place upon the
Premises in the same manner and to the same extent as of this Lease had been
executed subsequent to the execution, delivery, and recording of such Lease,
mortgage, or deed of trust.

          24.02   Subordination, Self-Operative, Subordination Agreement,
Nondisturbance. The subordination of this Lease to any mortgage or deed of trust
now or hereafter placed upon the Premises shall be automatic and self-operative
and no further instrument or evidence of subordination shall be necessary.
Without limiting such automatic and self-operative subordination, however,
Tenant shall, on demand, within ten (10) days of such demand, execute,
acknowledge, and deliver to Landlord or any grantee or assignee of Landlord any
and all instruments that may be necessary or proper to evidence the
subordination of this Lease and all rights hereunder to the lien of such
mortgage or deed of trust. In any and all events, so long as Tenant is not in
default under this Lease, Tenant's right of possession shall not be disturbed.

          24.03   Attornment. Tenant covenants and agrees that, upon any
mortgage foreclosure or foreclosure under a deed of trust, or deed in lieu
thereof, it will attorn to any mortgagee, trustee, assignee, or any purchaser at
any foreclosure sale as its Landlord, and this Lease shall continue in full
force and effect as a direct Lease between Tenant herein and such party upon all
terms, conditions, and agreements set forth in this Lease.
<PAGE>

          24.04   Attornment to Successor. In the event Landlord or any
successor owner of the Premises shall transfer the Premises, which transfer may
be freely effected by Landlord without the consent or approval of Tenant,
Landlord or such successor owner, as the case may be, shall thereupon be
released from all future liabilities and obligations of Landlord under this
Lease and all such future liabilities and obligations shall thereupon
automatically be binding upon the new owner, and Tenant will attorn to any new
owner as its Landlord, and this Lease shall continue in full force and effect as
a direct Lease between Tenant herein and such party upon all terms, conditions,
and agreements set forth in this Lease.

          24.05  Tenant's Right to Quiet Enjoyment. Notwithstanding such
subordination, as to hereafter occurring matters, Tenant's right to quiet
enjoyment of the premises shall not be disturbed if Tenant is not in default and
so long as Tenant shall pay the rent and observe and perform all of the
provisions of this Lease, unless this Lease is otherwise terminated pursuant to
its terms.

                                  ARTICLE XXV
                       Landlord's Access to the Premises

          Landlord, or its agents or authorized representatives, shall have
access to the Premises at any time during normal business hours for the purposes
of examining or inspecting the condition of same. In the event of any emergency
such as, but not limited to, a fire, flood, or severe windstorm, Landlord shall
have free access to the Premises for the purpose of examining or inspecting
damage done to them. Unless Tenant shall have given notice of its exercising its
option to extend the Term of this Lease pursuant to Article III of this Lease
entitled "Term and Extensions", Landlord shall have the right, for the twelve
(12) months prior to expiration of this Lease or any extensions hereof, to show
the Premises to prospective tenants, at reasonable times during normal business
hours, or at other times upon reasonable notice to Tenant. Landlord further
reserves the right to show the Premises to prospective purchasers or lenders any
time during the Term of the Lease, during normal business hours, or at other
times upon reasonable notice to Tenant.

                                  ARTICLE XXVI
                            Environmental Compliance

          26.01   Definitions. For purposes of this Lease:

          (a)     the term "Environmental Laws" shall mean and include the
     Resource Conversation and Recovery Act, as amended by the Hazardous and
     Solid Waste Amendments of 1984, the Comprehensive Environmental Response,
     Compensation and Liability Act, the Hazardous Materials Transportation Act,
     the Toxic Substances Control Act, the Federal Insecticide, Fungicide and
     Rodenticide Act and any and all other applicable federal, state and local
     environmental laws, ordinances, rules, requirements, regulations and
     publications, as any of the foregoing may have been or may be from time to
     time amended, supplemented or supplanted and any and all other federal,
     state or local laws, ordinances, rules, requirements, regulations and
     publications, now or hereafter existing, relating to the preservation of
     the environment or the regulation or control of toxic or hazardous
     substances or materials; and

          (b)     the term "Regulated Substance" shall mean and include any,
     each and all substances or materials now or hereafter regulated pursuant to
     any Environmental Laws, including, but not limited to, any such substance
     or material now or hereafter defined as or deemed to be a "regulated
     substance, " "pesticide," "hazardous substance" or "hazardous waste",
     "asbestos,"
<PAGE>

     "polychlorobiphenyls", "petroleum" or included in any similar
     or like classification or categorization thereunder.

          26.02   Compliance. Tenant shall:

          (a)     not cause or permit any Regulated Substance to be placed,
     held, located, released, transported or disposed on, under, at or from the
     Premises or to otherwise adversely affect the Premises in violation of any
     Environmental Laws;

          (b)     at its own cost and expense contain at and remove from the
     Premises, and perform any other necessary or desirable remedial action
     regarding, any Regulated Substance in any way affecting the Premises if, as
     and when such containment, removal or other remedial action is required
     under any Environmental Laws and, whether or not so required, shall perform
     any containment, removal or remediation of any kind involving any Regulated
     Substance in any way affecting the Premises in compliance with the
     requirements of all Environmental Laws;

          (c)     provide Landlord with written notice (and a copy as may be
     applicable) of any of the following within ten (10) days thereof: (i)
     Tenant's obtaining knowledge or notice of any kind of the presence, or any
     actual or threatened release, of any Regulated Substance in any way
     affecting the Premises; (ii) Tenant's receipt or submission, or Tenant's
     obtaining knowledge or notice of any kind, of any report, citation, notice
     or other communication from or to any federal, state or local governmental
     or quasi-governmental authority regarding any Regulated Substance in any
     way affecting the Premises; or (iii) Tenant's obtaining knowledge or notice
     of any kind of the incurrence of any cost or expense by any federal, state
     or local governmental or quasi-governmental authority or any private party
     in connection with the assessment, monitoring, containment, removal or
     remediation of any kind of any Regulated Substance in any way affecting the
     Premises, or of the filing or recording of any lien on the Premises or any
     portion thereof in connection with any such action or Regulated Substance
     in any way affecting the Premises; and

          (d)     defend all actions against the Landlord and its Mortgagee and
     pay, protect, indemnify and save harmless Landlord and its Mortgagee from
     and against any and all liabilities, losses, damages, costs, expenses
     (including, without limitation, attorneys' and consultant's fees, response
     and clean-up costs, court costs, and litigation expenses), causes of
     action, suits, claims demands or judgments of any nature relating to (i)
     the presence, disposal, release or threatened release of any Regulated
     Substance; (ii) any personal injury (including wrongful death) or property
     damage (real or personal) arising out of or relating to any Regulated
     Substance; or (iii) any Environmental Laws, Regulated Substance or other
     environmental matters. If at or after the expiration or other termination
     of this Lease any response or clean up of a condition involving Regulated
     Substances existing at the expiration or other termination of this Lease is
     required by any federal, state or local governmental authority, Tenant
     shall remain solely responsible for such requirement and this Lease shall
     remain in full force and effect pursuant to the terms of Article XXII until
     such response or clean up is completed to the satisfaction of the
     respective governmental authority. The indemnity contained in this Section
     XXVI shall survive the expiration or earlier termination of this Lease.

          26.03   Environmental Testing. "Upon prior written notice from
Landlord, (i) in the event of the reasonable suspicion of Landlord that a
Regulated Substance is or may be found within the Premises in violation of
Environmental Laws or (ii) in connection with a bona fide sale or mortgage
transaction, Tenant shall permit such persons as Landlord may designate ("Site
Reviewers") to visit the Premises and
<PAGE>

perform environmental site investigations and assessments ("Site Assessments")
on the Premises for the purpose of determining whether there exists on the
Premises any violation of Environmental Laws or any condition with respect to
the environment that could result in liability to Landlord. Such Site
Assessments may include both above and below the ground testing and such other
tests as may be necessary, in the reasonable opinion of the Site Reviewers, to
conduct the Site Assessments and shall, to the extent reasonable, be scheduled
and conducted in a manner to minimize interference with Tenant's use of the
Premises. Tenant shall supply to the Site Reviewers such historical and
operational information regarding the Premises as may be reasonably requested by
the Site Reviewers to facilitate the Site Assessments, and shall make available
for meetings with the Site Reviewers appropriate personnel having knowledge of
such matters.

                                 ARTICLE XXVII
                                   Late Rent

Tenant hereby acknowledges that late payment by Tenant to Landlord of Rent and
other sums due hereunder will cause Landlord to incur costs not contemplated by
this Lease, the exact amount of which will be difficult to ascertain. Such costs
include, but are not limited to, processing and accounting charges, and late
charges which may be imposed on Landlord by the terms of any mortgage or trust
deed encumbering the Premises. Accordingly, if any installment of Rent or any
other sum due from Tenant shall not be received by Landlord or Landlord's
designee within seven (7) days after the date on which such sum is due, Tenant
shall pay to Landlord a late charge equal to the greater of 4% of such overdue
amount or the late charge, penalty or interest imposed on Landlord by its
Mortgagee as a result of any resulting late payment made to such Mortgagee. The
parties hereby agree that such late charge represents a fair and reasonable
estimate of the costs Landlord will incur by reason of late payment by Tenant.
Acceptance of such late charge, partial payments, or other matters by Landlord
shall in no event constitute a waiver of Tenant's default or Landlord's rights
with respect to such overdue amount or other default(s), nor prevent Landlord
from exercising any of the other rights and remedies allowed hereunder. All
remedies hereunder and at law shall be cumulative.

                                 ARTICLE XXVIII
                             Estoppel Certificates

Tenant will within ten (10) days, promptly execute, acknowledge, and deliver to
Landlord, upon request, a certificate of Tenant certifying that this Lease is
unmodified and is in full force and effect (or, if modified, that this Lease is
in full force and effect, as modified, and stating the date of each instrument
so modifying this Lease); the dates, if any, to which Rent and other charges
payable hereunder have been paid; whether, in the opinion of Tenant, any default
exists hereunder and, if so, the nature and period of existence thereof and what
action Landlord is taking or proposes to take with respect thereto and whether
notice thereof has been given to Landlord; and such other and further matters as
may reasonably be requested by Landlord and any mortgagee or purchaser of
Landlord. If such certificate is required to be delivered by a corporation, the
same shall be signed by the President or a Vice President and the Secretary or
an Assistant Secretary thereof, and if such certificate is required to be
delivered by a partnership, the same shall be signed by a general partner
thereof. Any certificate required under this Article may be relied upon by a
prospective purchaser, mortgagee, or other transferee of Landlord's interest
under this Lease.
<PAGE>

                                  ARTICLE XXIX
                                    Reports

Tenant agrees to furnish to Landlord, with reasonable promptness: (l) copies of
financial statements of Tenant (including, but not limited to, annual balance
sheets, income statements and surplus statements) prepared in accordance with
generally accepted accounting principals and certified by independent certified
public accountants; and (2) other financial statements, reports and documents
which the Tenant (i) files with or otherwise sends to the Securities and
Exchange Commission, whether pursuant to the Securities Act of 1933, as amended,
or the Securities Exchange Act of 1934 including, without limitation, Annual
Report on Form l0-K, Quarterly Report on Form l0-Q, Current Report on Form 8-K
and Proxy Statements and other Soliciting materials; (ii) files with any other
governmental commission, department or agency or any securities exchange; or
(iii) sends to or makes available to its shareholders. In addition to the
foregoing, Tenant shall obtain and deliver to Landlord, with reasonable
promptness, such other information respecting the operation of the Premises or
the financial condition and affairs of Tenant, as Landlord may from time to time
reasonably request.

                                  ARTICLE XXX
                       Provisions of General Application

          (a)     The language in all parts of this Lease shall in all cases be
     construed as a whole and according to its fair meaning, and not strictly
     for or against either Landlord or Tenant, and the construction of this
     Lease and any of its various provisions shall be unaffected by any argument
     or claim, whether or not justified, that it has been prepared, wholly or in
     substantial part, by or on behalf of Landlord or Tenant.

          (b)     The Article headings in this Lease are for convenience only
     and are not a part of this Lease, and do not in any was limit or simplify
     the terms and provisions of this Lease, nor should they be used to
     determine the intent of the parties.

          (c)     If any term, covenant, condition or provision of this Lease,
     or the application thereof to any person or circumstances, shall, to any
     extent, be invalid or unenforceable, the remainder of this Lease, or the
     application of such term or provision to persons or circumstances other
     than those as to which it is held invalid or unenforceable, shall not be
     affected thereby; and it is the intention of the parties hereto that if any
     provision of this Lease is capable of two constructions, one of which would
     render the provision invalid, and the other which would render the
     provision valid, then the provision shall have the meaning which renders it
     valid; and each term, covenant, condition and provision of this Lease shall
     be valid and be enforced to the fullest extent permitted by law.

          (d)     It is mutually covenanted and agreed by and between the
     parties that no waiver of a breach of any of the covenants or conditions of
     this Lease shall be construed to be a waiver of any succeeding breach of
     the same covenant or condition. It is further agreed by and between the
     parties that no modification, release, discharge or waiver of any provision
     of this Lease shall be of any force, effect or value unless in writing and
     signed by the Landlord and Tenant or their duly authorized agents.

          (e)     This Lease shall be governed and construed in accordance with
     the laws of the state wherein the Premises are located
<PAGE>

          (f)     The words "Landlord" and "Tenant" and the pronouns referring
     thereto, as used in this Lease, shall mean, where the context requires or
     permits, the persons named herein as Landlord and as Tenant, respectively,
     and their respective heirs, legal representatives, successors, and assigns,
     irrespective of whether singular or plural, or masculine, feminine, or
     neuter. The agreements and conditions in this Lease contained on the part
     of Landlord to be performed and observed shall be binding upon Landlord and
     its heirs, legal representatives, successors, and assigns, and shall endure
     to the benefit of Tenant and its heirs, legal representatives, successors,
     and assigns; and the agreements and conditions on the part of Tenant to be
     performed and observed hereunder shall be binding upon Tenant and its
     heirs, legal representatives, successors, and assigns, and shall endure to
     the benefit of Landlord and its heirs, legal representatives, successors,
     and assigns.

          (g)     Landlord and Tenant represent to each other that no broker or
     person is entitled to any commission by reason of the negotiation and
     execution of this Lease. Landlord and Tenant agree to hold the other
     harmless against any and all claims by any person for brokerage commissions
     arising out of any conversation, negotiations or other dealings held by it
     with any broker regarding this Lease.

          (h)     The parties will, at any time at the written request of either
     one, promptly execute duplicate originals of an instrument, in recordable
     form, which will constitute a short form of lease, setting forth a
     description of the Premises, the Term and any other portions hereof, except
     the rental provisions (unless required by statute), as either party may
     request. All costs incurred in connection with recording the short form of
     lease shall be paid by Tenant. If a party fails or refuses to execute and
     acknowledge a reasonable short form of lease within fifteen (15) days after
     notice of said request, the requesting party is authorized to, and is
     hereby appointed attorney-in-fact with full power and authority to execute
     and acknowledge said short form of lease on behalf of and in the name of
     the other Party.

          (i)     If, as a result of any breach or default in the performance of
     any of the provisions of this Lease, Landlord or Tenant uses the services
     of an attorney in order to secure compliance with such provisions or
     recover damages therefor from the breaching party, and if the non-breaching
     party is the prevailing party in any litigation resulting therefrom or
     settlement associated therewith, then the non-breaching party shall be
     entitled to recover from the breaching party any and all reasonable
     attorneys fees and expenses incurred by the non-breaching party in
     connection with such litigation or settlement.

          (j)     This instrument and the Agreement to Lease contain the entire
     and only agreement between the parties relating to the subject matter
     hereof, and no oral statements or representations or written matter not
     contained in these instruments shall have any force or effect. This Lease
     shall not be amended or modified in any way except by writing executed by
     both parties.

          (k)     The relationship between the parties hereto is solely that of
     Landlord and Tenant, and nothing in this Lease shall be construed as
     creating a partnership or joint venture between the parties hereto, it
     being the express intent of Landlord and Tenant that the business of Tenant
     on the Premises and elsewhere, and the good will thereof, shall be and
     remain the sole property of Tenant.
<PAGE>

          (l)     Throughout this Lease, wherever the context so requires, the
     singular shall include the plural, and the masculine gender shall include
     the feminine and neuter genders.

          (m)     There shall be no merger of this Lease or the leasehold estate
     created by this Lease with any other estate or interest in the Premises by
     reason of the fact of the same person, firm, corporation, or other entity
     acquiring or owning or holding, directly or indirectly, this Lease or the
     leasehold interest created by this Lease or any interest in this Lease, and
     any such other estate or interest in the Premises or any part thereof, and
     no such merger shall occur unless and until all corporations, firms, and
     other entities having an interest (including a security interest) in this
     Lease or the leasehold interest created by this Lease and any such other
     estate or interest in the Demised premises or any part thereof, shall join
     in a written instrument effecting such merger and shall duly record the
     same.

          (n)     In the event of a conflict between the terms of the Agreement
     to Lease and this Lease, the Agreement to Lease shall prevail.

     IN WITNESS WHEREOF, Landlord and Tenant have caused this Lease to be duly
executed and delivered in their respective names as of the date first above
written, and Tenant has provided Landlord with a certified copy of its corporate
resolution evidencing the authority of the person subscribing below to execute
leases such as this Lease on its behalf.

     IN WITNESS WHEREOF, each of the parties hereto has caused this Addendum to
be duly executed as of the day and year first above written.

Landlord:                    CHEROKEE EQUITIES, LLC


                             By:
                                --------------------------------
                             Name: David Allen Phillips
                             Title:   Its Manager

Tenant:                      STANFORD TELECOM CORPORATION, A
                             DELAWARE CORPORATION


                             By:
                                --------------------------------
                             Name: Ernest L. Dickens, Jr.
                             Title:  Vice President and Division General Manager
<PAGE>

ACKNOWLEDGEMENT
STATE OF COLORADO   )
                    ) SS.
COUNTY OF EL PASO   )

Before me, a Notary Public in and for said county and state personally appeared

of_____________, as_____ CHEROKEE EQUITIES, LLC, a Colorado Limited Liability
Company, who acknowledged that he did sign the foregoing instrument on behalf of
said limited liability company and acknowledged the same to be its free act and
deed and the free act and deed of him personally as such officer.

My Commission expires:________          ________________________Notary Public
              Seal


STATE OF COLORADO   )
                    ) SS.
COUNTY OF EL PASO   )

Before me, a Notary Public in and for said county and state personally appeared
Ernest I. Dickens, Jr., as Vice President and Division General Manager of
Stanford Telecom Corporation, a Delaware corporation, who acknowledged that he
did sign the foregoing instrument on behalf of said corporation and acknowledged
the same to be its free act and deed and the free act and deed of him personally
as such officer.

My Commission expires:________          ________________________Notary Public
              Seal