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                               SECURITY AGREEMENT

           (Accounts, Inventory, Equipment, Chattel Paper, Documents,
              Instruments, General Intangibles and Other Property)

                                    Between

                               4630 REALTY, INC.

                                      and

                   CAPSTAR RADIO BROADCASTING PARTNERS, INC.

                               September 15, 1998


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                               SECURITY AGREEMENT

           Accounts, Inventory, Equipment, Chattel Paper, Documents,
              Instruments, General Intangibles and Other Property

          
           THIS SECURITY AGREEMENT (this "Agreement") is made as of September
15, 1998, by 4630 REALTY, INC., a Delaware corporation with principal offices
at 750 B Street, Suite 1920, San Diego, California 92101 ("Debtor"); for
CAPSTAR RADIO BROADCASTING PARTNERS, INC., a Delaware corporation with offices
at 600 Congress Avenue, Suite 1400, Austin, Texas 78701 ("Secured Party").

                                    RECITALS

           A. On even date herewith, Secured Party is loaning to Debtor and
Debtor is borrowing from Secured Party $650,000 for the purchase of real
property located at 4630 Antelope Creek, Lincoln, Lancaster County, Nebraska
and evidenced by a Promissory Note executed by Debtor dated the date hereof
(hereinafter called the "Promissory Note").

           B. Secured Party has conditioned its loan to Debtor upon the
execution and delivery by Debtor of this Agreement, and Debtor has agreed to
enter into this Agreement.

           C. Therefore, for other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, Debtor hereby agrees with
Secured Party as follows:

                                   ARTICLE 1

                               SECURITY INTEREST

           Section 1.01 Grant of Security Interest. Debtor hereby assigns and
grants to Secured Party a security interest in and right of set-off against the
assets referred to in Section 1.02 (the "Collateral") to secure the prompt
payment and performance of the "Obligations" (as defined in Section 2.02) and
the performance by Debtor of this Agreement.

           Section 1.02 Collateral. The Collateral consists of the following
types or items of property, but only to the extent owned by Debtor, (including
property hereafter acquired by Debtor as well as property which Debtor now owns
or in which Debtor has rights):

                    (a) All of Debtor's accounts, inventory, equipment, chattel
           paper, documents, instruments and general intangibles, including,
           without limitation, any of the foregoing which may be more
           specifically indicated in the remainder of this Section.

                    (b) (i) Any related or additional property from time to
           time delivered to or deposited with Secured Party by or for the
           account of Debtor; (ii) all certificates of title or other documents
           evidencing ownership or possession of or otherwise relating to any
           property referred to in this Section; (iii) all property used or
           usable in connection with any property


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           referred to in this Section; (iv) all policies of insurance (whether
           or not required by Secured Party) covering any property referred to
           in this Section; (v) all goods which were at any time included in
           the Collateral and which are returned to or for the account of
           Debtor following their sale, lease or other disposition; (vi) all
           proceeds, products, replacements, additions to, substitutions for,
           accessions of, and property necessary for the operation of any of
           the property referred to in this Section, including, without
           limitation, insurance payable as a result of loss or damage to any
           of the property referred to in this Section, refunds of unearned
           premiums of any such insurance policy and claims against third
           parties; and (vii) all books and records related to any of the
           property referred to in this Section, including, without limitation,
           any and all books of account, customer lists and other records
           relating in any way to the accounts, chattel paper, instruments or
           inventory referred to in this Section.

                    (c) All general intangibles related to any property
           referred to in this Section, including, without limitation, all (i)
           letters of credit, bonds, guaranties, purchase or sales agreements
           and other contractual rights, rights to performance, and claims for
           damages, refunds (including tax refunds) or other monies due or to
           become due; (ii) orders, franchises, permits, certificates,
           licenses, consents, exemptions, variances, authorizations or other
           approvals by any governmental agency or court; (iii) consulting,
           engineering and technological information and specifications, design
           data, patent rights, trade secrets, literary rights, copyrights,
           trademarks, labels, trade names and other intellectual property;
           (iv) business records, computer tapes and computer software; (v)
           goodwill; and (vi) other intangible personal property, whether
           similar or dissimilar to the property referred to in this Section.

           It is expressly contemplated that additional property may from time
to time be pledged, assigned or granted to Secured Party as additional security
for the Obligations, and the term "Collateral" as used herein shall be deemed
for all purposes hereof to include all such additional property, together with
all other property of the types described above related thereto.

           Section 1.03 Location of Collateral. The Collateral is located or
(except as otherwise permitted by Section 4.01) shall be located only in the
following places (provided that the Collateral shall be subject to the security
interest created by this Agreement irrespective of whether or not the
Collateral is located in the following places): Lincoln, Nebraska.

           Section 1.04 Filing Information Regarding Certain Collateral. The
Collateral includes property that is or may be or become fixtures on the real
property described in Exhibit A attached hereto and made a part hereof. Debtor
is a record owner of such real property (as shown in the real estate records of
the jurisdiction where such real estate is located).


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                                   ARTICLE 2

                                  DEFINITIONS

           Section 2.01 Terms Defined Above. As used in this Agreement, the
terms defined above shall have the meanings respectively assigned to them.

           Section 2.02 Certain Definitions. As used in this Agreement, the
following terms shall have the following meanings, unless the context otherwise
requires:

                      "Accounts" means all accounts, chattel paper and
           instruments (as such terms are defined in the Code) at any time
           included in the Collateral.

                      "Account Debtor" means any person or entity liable
           (whether directly or indirectly, primarily or secondarily) for the
           payment or performance of any obligations included in the
           Collateral, whether as an account debtor (as defined in the Code),
           obligor on an instrument, issuer of documents or securities,
           guarantor or otherwise.

                      "Agreement" means this Security Agreement, as the same
           may from time to time be amended or supplemented.

                      "Code" means the Uniform Commercial Code as presently in
           effect in the State of Texas, Business and Commerce Code, Chapters 1
           through 9. Unless otherwise indicated by the context herein, all
           uncapitalized terms which are defined in the Code shall have their
           respective meanings as used in Chapter 9 of the Code.

                      "Event of Default" means any event specified in Section
           6.01.

                      "Highest Lawful Rate" means the maximum rate of
           nonusurious interest allowed from time to time by applicable law.

                      "Inventory" means all inventory (as defined in the Code)
           at any time included in the Collateral.

                      "Obligations" means the Promissory Note and any and all
           renewals, extensions for any period, rearrangements or enlargements
           thereof, whether evidenced by any note or other instrument or
           agreement, whether arising by an extension of credit, letter of
           credit, overdraft, endorsement, loan, guaranty, indemnification or
           otherwise, whether direct or indirect.


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                                   ARTICLE 3

                         REPRESENTATIONS AND WARRANTIES

           In order to induce Secured Party to accept this Agreement, Debtor
represents and warrants to Secured Party (which representations and warranties
will survive the creation and payment of the Obligations) that:

           Section 3.01 Ownership of Collateral Encumbrances; Valid and Binding
Agreement. Debtor is the legal and beneficial owner of the Collateral free and
clear of any adverse claim, lien, security interest, option or other charge or
encumbrance except for the security interest created by this Agreement, and
Debtor has full right, power and authority to assign and grant a security
interest in the Collateral to Secured Party. This Agreement constitutes a
legal, valid and binding obligation of Debtor enforceable against Debtor in
accordance with its terms. The execution, delivery and performance of this
Agreement will not violate the terms of any contract, agreement, law,
regulation, order, injunction, judgment, decree or writ to which Debtor is
subject and does not require the consent or approval of any other person or
entity.

           Section 3.02 No Required Consent. Subject to the terms of the
Amended and Restated Credit Agreement dated as of May 30, 1997, among Triathlon
Broadcasting Company, Triathlon Broadcasting of Wichita, Inc., Triathlon
Broadcasting of Lincoln, Inc., Triathlon Broadcasting of Omaha, Inc., Triathlon
Broadcasting of Spokane, Inc., Triathlon Broadcasting of Tri-Cities, Inc.,
Triathlon Broadcasting of Colorado Springs, Inc., Triathlon Broadcasting of
Little Rock, Inc., the lenders party thereto from time to time and AT&T
Commercial Finance Corporation, individually and as Administrative Agent, as
amended (together with the documents and instruments executed and delivered in
connection therewith, the "Triathlon Credit Agreement"), no authorization,
consent, approval or other action by, and no notice to or filing with, any
governmental authority or regulatory body (other than the filing of financing
statements) is required for (i) the due execution, delivery and performance by
Debtor of this Agreement, (ii) the grant by Debtor of the security interest
granted by this Agreement, (iii) the perfection of such security interest or
(iv) the exercise by Secured Party of its rights and remedies under this
Agreement.

           Section 3.03 First Priority Security Interest. The grant of the
security interest in the Collateral pursuant to this Agreement creates a valid
and perfected first priority security interest in the Collateral, enforceable
against Debtor and all third parties and securing payment of the Obligations.

           Section 3.04 No Filings By Third Parties. No financing statement or
other public notice or recording covering the Collateral is on file in any
public office (other than any financing statement or other public notice or
recording naming Secured Party as the secured party therein), and Debtor will
not execute any such financing statement or other public notice or recording so
long as any of the Obligations are outstanding.


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           Section 3.05 No Name Changes. Debtor has not, during the preceding
five years, entered into any contract, agreement, security instrument or other
document using a name other than, or been known by or otherwise used any name
other than, the name used by Debtor herein.

           Section 3.06 Location of Debtor and Collateral. Debtor's chief
executive office and Debtor's records concerning the Collateral are located at
the address or location set forth in the opening paragraph hereof. The
Collateral is located at Debtor's address set forth in the opening paragraph
hereof or at the location(s), if any, specified in Section 1.02 or 1.03. Any
Collateral not at such location(s) nevertheless remains subject to Secured
Party's security interest.

           Section 3.07 Collateral. All statements or other information
provided by Debtor to Secured Party describing or with respect to the
Collateral is or (in the case of subsequently furnished information) will be
when provided correct and complete in all material respects. The delivery at
any time by Debtor to Secured Party of additional Collateral or of additional
descriptions of Collateral shall constitute a representation and warranty by
Debtor to Secured Party hereunder that the representations and warranties of
this Article 3 are correct insofar as they would pertain to such Collateral or
the descriptions thereof.

                                   ARTICLE 4

                            COVENANTS AND AGREEMENTS

           Debtor will at all times comply with the covenants and agreements
contained in this Article 4, from the date hereof and for so long as any part
of the Obligations are outstanding.

           Section 4.01 Change in Location of Collateral or Debtor. Debtor will
notify Secured Party on or before the date of any change in location of the
Collateral. Debtor will not, without Secured Party's prior written consent,
change the location of the Collateral to any state, county or other
jurisdiction in which Secured Party has not already filed a financing statement
or taken other necessary steps to perfect its security interests in the
Collateral or to maintain such perfection. Debtor will give Secured Party 30
days' prior written notice of (i) the opening or closing of any place of
Debtor's business or (ii) any change in the location of Debtor's chief
executive office or address.

           Section 4.02 Change in Debtor's Name or Corporate Structure. Debtor
will not change its name, identity or corporate structure (including, without
limitation, any merger, consolidation or sale of substantially all of its
assets) without notifying Secured Party of such change in writing at least 30
days prior to the effective date of such change. Without the express written
consent of Secured Party, however, Debtor will not engage in any other business
or transaction under any name other than Debtor's name hereunder.

           Section 4.03 Documents; Collateral in Possession of Third Parties.
If certificates of title or other documents evidencing ownership or possession
of the Collateral are issued or outstanding, Debtor will cause the interest of
Secured Party to be properly noted thereon and will, forthwith upon receipt,
deliver same to Secured Party. If any Collateral is at any time in the
possession or control


<PAGE>



of any warehouseman, bailee, agent or independent contractor, Debtor shall
notify such person or entity of Secured Party's security interest in such
Collateral. Upon Secured Party's request, Debtor shall instruct any such person
or entity to hold all such Collateral for Secured Party's account subject to
Debtor's instructions, or, if an Event of Default shall have occurred, subject
to Secured Party's instructions.

           Section 4.04 Delivery of Letters of Credit and Instruments. Debtor
will deliver each letter of credit, if any, included in the Collateral to
Secured Party, in each case forthwith upon receipt by or for the account of
Debtor. If any Account becomes evidenced by a promissory note, trade acceptance
or any other instrument for the payment of money (other than checks or drafts
in payment of Accounts collected by Debtor in the ordinary course of business
prior to notification by Secured Party under Section 5.10), Debtor will
immediately deliver such instrument to Secured Party appropriately endorsed
and, regardless of the form of presentment, demand, notice of dishonor, protest
and notice of protest with respect thereto, Debtor will remain liable thereon
until such instrument is paid in full.

           Section 4.05 Maintenance of Existence. Debtor will maintain Debtor's
corporate existence and remain in good standing and qualified to do business in
all jurisdictions pursuant to the laws of which it is so required.

           Section 4.06 Sale, Disposition or Encumbrance of Collateral. Except
as permitted by Section 4.14 or with Secured Party's prior written consent,
Debtor will not in any way encumber any of the Collateral (or permit or suffer
any of the Collateral to be encumbered) or sell, assign, lend, rent, lease or
otherwise dispose of or transfer any of the Collateral to or in favor of any
person or entity other than Secured Party.

           Section 4.07 Proceeds of Collateral. Debtor will deliver to Secured
Party promptly upon receipt all proceeds delivered to Debtor from the sale or
disposition of any Collateral. If chattel paper, documents or instruments are
received as proceeds, which are required to be delivered to Secured Party, they
will be, immediately upon receipt, properly endorsed or assigned and delivered
to Secured Party as Collateral. This Section 4.07 shall not be construed to
permit sales or dispositions of Collateral except as may be elsewhere expressly
permitted by this Agreement.

           Section 4.08 Payment of Taxes and Liens. Debtor will pay prior to
delinquency all taxes, charges, liens and assessments against the Collateral.

           Section 4.09 Records and Information. Debtor shall keep accurate and
complete records of the Collateral (including proceeds). These records shall
reflect complete and accurate stock records of the Inventory and all facts
concerning each Account. Debtor shall conduct a physical count of the Inventory
at such intervals as Secured Party requests and promptly supply Secured Party
with a copy of such count accompanied by a report of the value (valued at the
lower of cost or market value) of the Inventory. Secured Party may at any time
have access to, examine, audit, make extracts from and inspect without
hindrance or delay Debtor's records, files and the Collateral. Debtor will
promptly provide written notice to Secured Party of all information which in
any way relates to or affects the filing of any financing statement or other
public notices or recordings, or the delivery and 


<PAGE>



possession of items of Collateral for the purpose of perfecting a security
interest in the Collateral. Debtor will also promptly furnish such information
as Secured Party may from time to time reasonably request regarding (i) the
business, affairs or financial condition of Debtor or (ii) the Collateral or
Secured Party's rights or remedies with respect thereto. Any balance sheets or
financial statements requested by Secured Party pursuant to this Section 4.09
shall conform to generally accepted accounting principles.

           Section 4.10 Performance of Obligations. Debtor will promptly and
properly perform all of its obligations under this Agreement and any other
agreement or contract of any kind now or hereafter existing as security for or
in connection with the payment of the Obligations.

           Section 4.11 Further Assurances. Upon the request of Secured Party,
Debtor shall (at Debtor's expense) execute and deliver all such assignments,
certificates, financing statements or other documents and give further
assurances and do all other acts and things as Secured Party may reasonably
request to perfect Secured Party's interest in the Collateral or to protect,
enforce or otherwise effect Secured Party's rights and remedies hereunder.

           Section 4.12 Insurance. Debtor shall maintain, with financially
sound and reputable insurers, insurance satisfactory in all respects to Secured
Party covering all insurable risks with respect to the Collateral, including
standard extended coverage, in an amount at least equal to the value of the
Collateral. Policies evidencing any such insurance shall contain a standard
mortgagee's endorsement providing for payment of any loss to Secured Party, and
such policies shall further provide for 30 days' minimum written cancellation
notice to Secured Party. Debtor shall furnish evidence satisfactory to Secured
Party of compliance with these insurance provisions.

           Section 4.13 Condition of Collateral. Debtor will maintain all the
Collateral in good condition, repair and working order, and in accordance with
any manufacturer's manual. Debtor will not misuse, abuse, waste, destroy or
endanger the Collateral or allow it to deteriorate, except for ordinary wear
and tear from its intended use. Debtor will repair, replace or otherwise
improve the Collateral as may be necessary. Debtor will not use any Collateral
in violation of any law, statute, ordinance, regulation or administrative
order, or suffer it to be so used.

           Section 4.14 Collateral Attached to Other Property. In the event
that the Collateral is to be attached or affixed to any real property (as
described in Section 1.04 or otherwise), Debtor hereby agrees that this
Agreement may be filed for record in any appropriate real estate records as a
financing statement which is a fixture filing. If Debtor is not the record
owner of such real property, Debtor will provide Secured Party with any
additional security agreements or financing statements necessary for the
perfection of Secured Party's security interest in the Collateral. If the
Collateral is wholly or partly affixed to real estate or installed in or
affixed to other goods, Debtor will, on demand of Secured Party, furnish
Secured Party with a disclaimer (including landlord's or other lien waivers or
releases, if applicable), signed by all persons or entities having an interest
in the real estate or other goods to which the Collateral may have become
affixed, of any prior interest to Secured Party's interest in the Collateral.


<PAGE>



           Section 4.15 Collateral Separate and Distinct. Debtor shall at all
times keep the Collateral, including proceeds, or cause it to be kept (when in
the possession of warehousemen, bailees, agents, independent contractors or
other third parties), separate and distinct from other property (except as to
any property which is to become attached or affixed as described in Section
1.04).

                                   ARTICLE 5

                   RIGHTS, DUTIES AND POWERS OF SECURED PARTY

           The following rights, duties and powers of Secured Party are
applicable irrespective of whether an Event of Default occurs and is
continuing:

           Section 5.01 Non-judicial Enforcement. Secured Party may enforce its
rights hereunder without prior judicial process or judicial hearing, and to the
extent permitted by law Debtor expressly waives any and all legal rights which
might otherwise require Secured Party to enforce its rights by judicial
process.

           Section 5.02 Discharge Encumbrances. Secured Party may, at its
option, discharge any taxes, liens, security interests or other encumbrances at
any time levied or placed on the Collateral, may pay for insurance on the
Collateral and may pay for the maintenance and preservation of the Collateral.
Debtor agrees to reimburse Secured Party upon demand for any payment so made,
plus interest thereon from the date of Secured Party's demand at the Highest
Lawful Rate.

           Section 5.03 Attorney-in-Fact. Debtor hereby irrevocably appoints
Secured Party as Debtor's attorney-in-fact, with full authority in the place
and stead of Debtor and in the name of Debtor or otherwise, from time to time
in Secured Party's discretion, but at Debtor's cost and expense and without
notice to Debtor to:

                    (a) obtain, adjust, sell and cancel any insurance with
           respect to the Collateral and endorse any draft drawn by insurers of
           the Collateral, and Secured Party may apply any proceeds or unearned
           premiums of such insurance to the Obligations (whether or not due);

                    (b) take any action and to execute any assignment,
           certificate, financing statement, notification, document or
           instrument which Secured Party may deem necessary or advisable to
           accomplish the purposes of this Agreement, including, without
           limitation, to receive, endorse and collect all instruments made
           payable to Debtor representing any payment or other distribution in
           respect of the Collateral or any part thereof and to give full
           discharge for the same; and

                    (c) receive, change the address for delivery, open and
           dispose of mail addressed to Debtor, and to execute, assign and
           endorse negotiable and other instruments for the payment of money,
           documents of title or other evidences of payment, shipment or
           storage for any form of Collateral on behalf of and in the name of
           Debtor.


<PAGE>



           Section 5.04 Transfer of Collateral. Secured Party may transfer any
or all of the Obligations, and upon any such transfer Secured Party may
transfer its interest in any or all of the Collateral and shall be fully
discharged thereafter from all liability therefor. Any transferee of the
Collateral shall be vested with all rights, powers and remedies of Secured
Party hereunder.

           Section 5.05 Licenses and Rights to Use Collateral. In connection
with any transfer or sale (to Secured Party or any other person or entity) of
the Collateral, Secured Party is hereby granted a transferable license or other
right to use, without any charge, any of Debtor's labels, patents, copyrights,
trade names, trade secrets, trademarks or other similar property in completing
production, advertising or selling such Collateral. Debtor's rights under all
licenses and franchise agreements shall inure to the benefit of Secured Party
and any transferee of all or any part of the Collateral.

           Section 5.06 Cumulative and Other Rights. The rights, powers and
remedies of Secured Party hereunder are in addition to all rights, powers and
remedies given by law or in equity. The exercise by Secured Party of any one or
more of the rights, powers and remedies herein shall not be construed as a
waiver of any other rights, powers and remedies, including, without limitation,
any other rights of set-off. If any of the Obligations are given in renewal,
extension for any period or rearrangement, or applied toward the payment of
debt secured by any lien, Secured Party shall be, and is hereby, subrogated to
all the rights, titles, interests and liens securing the debt so renewed,
extended, rearranged or paid.

           Section 5.07 Disclaimer of Certain Duties. The powers conferred upon
Secured Party by this Agreement are to protect its interest in the Collateral
and shall not impose any duty upon Secured Party to exercise any such powers.
Debtor hereby agrees that Secured Party shall not be liable for, nor shall the
indebtedness evidenced by the Obligations be diminished by, Secured Party's
delay or failure to collect upon, foreclose, sell, take possession of or
otherwise obtain value for the Collateral.

           Section 5.08 Waiver of Notice; Demand and Presentment. Debtor hereby
waives any demand, notice of default, notice of acceleration of the maturity of
the Obligations, notice of intention to accelerate the maturity of the
Obligations, presentment, protest and notice of dishonor as to any action taken
by Secured Party in connection with this Agreement, or any instrument or
document.

           Section 5.09 Proceeds. If so requested by Debtor, any payments
received by Secured Party on the Accounts or as proceeds of other Collateral
shall upon final collection by Secured Party be credited towards payment of the
Obligations. In the absence of such request from Debtor, and until so
requested, Secured Party may at Secured Party's option either (i) hold such
collected payments as cash Collateral (and Secured Party may at any time place
a hold or freeze on all or a part of any deposit account of Debtor containing
deposits of such payments up to the amount of such deposits) or (ii) credit
such collected payments towards payment of the Obligations whether such
Obligations are due or not.

                                   ARTICLE 6



<PAGE>

                               EVENTS OF DEFAULT


           Section 6.01 Events. Any of the following events shall constitute an
Event of Default under this Agreement:

                    (a) Payments - Debtor defaults in any payment due and owing
           pursuant to the Obligations which shall continue for a period of 5
           days after notice;

                    (b) Representations and Warranties - any representation or
           warranty made by Debtor to Secured Party proves to have been
           incorrect in any material respect as of the date thereof;

                    (c) Covenants - default is made by Debtor in the
           performance of any covenant or agreement contained in this Agreement
           or in any other document now or hereafter executed in connection
           with or as security for the Obligations which shall continue for 20
           days after notice, except if it would require more than 20 days to
           cure provided Grantor begins to diligently prosecute a cure within
           such 20 day period, in which case shall continue after Grantor
           ceases prosecution of a cure;

                    (d) Legal Compliance - the violation by Debtor of, or the
           failure of the Collateral to comply with, any applicable law,
           statute, ordinance, regulation or administrative order if, as a
           result of such violation or noncompliance, the value of the
           Collateral or the perfection or priority of Secured Party's security
           interests therein may be, in the sole opinion of Secured Party,
           materially impaired, which shall continue for 20 days after notice,
           except if it would require more than 20 days to cure provided
           Grantor begins to diligently prosecute a cure within such 20 day
           period, in which case shall continue after Grantor ceases
           prosecution of a cure;

                    (e) Loss, Damage or Destruction of Collateral - the loss,
           theft, substantial damage to or destruction of the Collateral or of
           any material portion thereof (whether or not covered by insurance);

                    (f) Judgments, etc. - the entry of a judgment, issuance of
           an injunction, order of attachment, or any other process against
           Debtor or the Collateral which in the sole opinion of Secured Party
           impairs Debtor's ability to pay or perform the Obligations;

                    (g) Termination, Insolvency, etc. - Debtor shall
           respectively: (i) dissolve or otherwise terminate its existence in
           its form as of the date hereof, (ii) become insolvent or suffer a
           business failure, (iii) have a custodian, receiver or agent
           appointed or authorized to take charge of its properties, (iv) make
           an assignment for the benefit of creditors or call a meeting of
           creditors for the composition of debts, or (v) be subject to the
           commencement of any proceeding in bankruptcy or under other
           insolvency laws.



<PAGE>

           Section 6.02 Remedies. Upon the occurrence and during the
continuance of any Event of Default, Secured Party may take any or all of the
following actions after reasonable notice to Debtor:

                    (a) Declare all or part of the indebtedness pursuant to the
           Obligations immediately due and payable and enforce payment of the
           same by Debtor; provided that in the event of an Event of Default
           under clause (g) of Section 6.01, the Obligations shall immediately
           become due and payable without requirement of notice to Debtor.

                    (b) Take possession of the Collateral, or at Secured
           Party's request Debtor shall, at Debtor's cost, assemble the
           Collateral and make it available at a location to be specified by
           Secured Party which is reasonably convenient to Debtor and Secured
           Party. Secured Party may, at its option, render any equipment
           unusable that may be included in the Collateral, or, at Secured
           Party's request, Debtor will render it unusable. In any event,
           Debtor shall bear the risk of accidental loss or damage to or
           diminution in value of the Collateral, and Secured Party will not
           have any liability whatsoever for failure to obtain or maintain
           insurance, nor to determine whether any insurance ever in force is
           adequate as to amount or as to risk insured.

                    (c) Sell or lease, in one or more sales or leases and in
           one or more parcels, or otherwise dispose of any or all of the
           Collateral in its then condition or in any other commercially
           reasonable manner as Secured Party may elect, upon reasonable notice
           to Debtor, in a public or private transaction, at any location as
           deemed reasonable by Secured Party (including, without limitation,
           Debtor's premises), either for cash or credit or for future delivery
           at such price as Secured Party may deem fair, and (unless prohibited
           by the Code, as adopted in any applicable jurisdiction) Secured
           Party may be the purchaser of any or all Collateral so sold and may
           apply upon the purchase price therefor any Obligations secured
           hereby. Any such sale or transfer by Secured Party either to itself
           or to any other person or entity shall be absolutely free from any
           claim or right by Debtor, including any equity or right of
           redemption, stay or appraisal which Debtor has or may have under any
           rule of law, regulation or statute now existing or hereafter
           adopted. Upon any such sale or transfer, Secured Party shall have
           the right to deliver, assign and transfer to the purchaser or
           transferee thereof the Collateral so sold or transferred. It shall
           not be necessary that the Collateral or any part thereof be present
           at the location of any such sale or transfer. Secured Party may, at
           its discretion and upon reasonable notice to Debtor, provide for a
           public sale, and any such public sale shall be held at such time or
           times within ordinary business hours and at such place or places as
           Secured Party may fix in the notice of such sale. Secured Party
           shall not be obligated to make any sale pursuant to any such notice.
           Except as required by law, Secured Party may, without publication,
           adjourn any public or private sale by announcement at any time and
           place fixed for such sale, and such sale may be made at any time or
           place to which the same may be so adjourned. In the event any sale
           or transfer hereunder is not completed or is defective in the
           opinion of Secured Party, such sale or transfer shall not exhaust
           the rights of Secured Party hereunder, and Secured Party shall have
           the right, upon reasonable notice to Debtor, to cause one or more
           subsequent sales or transfers to be made hereunder. In the event
           that any of the Collateral is sold or transferred  


<PAGE>


           on credit, or to be held by Secured Party for future delivery to a
           purchaser or transferee, the Collateral so sold or transferred may
           be retained by Secured Party until the purchase price or other
           consideration is paid by the purchaser or transferee thereof, but in
           the event that such purchaser or transferee fails to pay for the
           Collateral so sold or transferred or to take delivery thereof,
           Secured Party shall not incur any liability in connection therewith.
           If only part of the Collateral is sold or transferred such that the
           Obligations remain outstanding (in whole or in part), Secured
           Party's rights and remedies hereunder shall not be exhausted, waived
           or modified, and Secured Party is specifically empowered to make one
           or more successive sales or transfers until all the Collateral shall
           be sold or transferred and all the Obligations are paid. In the
           event that Secured Party elects not to sell the Collateral, Secured
           Party retains its rights to lease or otherwise dispose of or utilize
           the Collateral or any part or parts thereof in any manner authorized
           or permitted by law or in equity, and to apply the proceeds of the
           same towards payment of the Obligations. Each and every method of
           disposition of the Collateral described in this subsection or in
           subsection (f) shall constitute disposition in a commercially
           reasonable manner.

                    (d) Take possession of all books and records of Debtor
           pertaining to the Collateral. Secured Party shall have the authority
           to enter upon any real property or improvements thereon in order to
           obtain any such books or records, or any Collateral located thereon,
           and remove the same therefrom without liability.

                    (e) Apply proceeds of the disposition of the Collateral to
           the Obligations in any manner elected by Secured Party and permitted
           by the Code or otherwise permitted by law or in equity. Such
           application may include, without limitation, the reasonable expenses
           of retaking, holding, preparing for sale or other disposition, and
           the reasonable attorneys' fees and legal expenses incurred by
           Secured Party.

                    (f) Appoint any person or entity as agent to perform any
           act or acts necessary or incident to any sale or transfer by Secured
           Party of the Collateral. Additionally, any sale or transfer
           hereunder may be conducted by an auctioneer or any officer or agent
           of Secured Party.

                    (g) Apply and set-off (i) any deposits of Debtor now or
           hereafter held by Secured Party; (ii) all claims of Debtor against
           Secured Party, now or hereafter existing; (iii) any other property,
           rights or interests of Debtor which come into the possession or
           custody or under the control of Secured Party; and (iv) the proceeds
           of any of the foregoing as if the same were included in the
           Collateral. Secured Party agrees to notify Debtor promptly after any
           such set-off or application; provided, however, the failure of
           Secured Party to give any notice shall not affect the validity of
           such set-off or application.

           Section 6.03 Reasonable Notice. If any applicable provision of any
law requires Secured Party to give reasonable notice of any sale or disposition
or other action, Debtor hereby agrees that ten days' prior written notice shall
constitute reasonable notice thereof. Such notice, in the case of public sale,
shall state the time and place fixed for such sale and, in the case of private
sale, the time after which such sale is to be made.


<PAGE>



                                   ARTICLE 7

                            MISCELLANEOUS PROVISIONS

           Section 7.01 Notices. Any notice required or permitted to be given
under or in connection with this Agreement shall be in writing and shall be
mailed by first class or express mail, postage prepaid, or sent by telex,
telegram, telecopy or other similar form of rapid written transmission or
personally delivered to the receiving party. All such communications shall be
mailed, sent or delivered at the address respectively indicated in the opening
paragraph hereof or at such other address as either party may have furnished
the other party in writing. Any communication so addressed and mailed shall be
deemed to be given when so mailed, any notice so sent by rapid written
transmission shall be deemed to be given when receipt of such transmission is
acknowledged by the receiving operator or equipment, and any communication so
delivered in person shall be deemed to be given when receipted for or actually
received by Debtor or Secured Party, as the case may be.

           Section 7.02 Amendments and Waivers. Secured Party's acceptance of
partial or delinquent payments or any forbearance, failure or delay by Secured
Party in exercising any right, power or remedy hereunder shall not be deemed a
waiver of any obligation of Debtor, or of any right, power or remedy of Secured
Party; and no partial exercise of any right, power or remedy shall preclude any
other or further exercise thereof. Secured Party may remedy any Event of
Default hereunder or in connection with the Obligations without waiving the
Event of Default so remedied. Debtor hereby agrees that if Secured Party agrees
to a waiver of any provision hereunder, or an exchange of or release of the
Collateral, or the addition or release of any person or entity, any such action
shall not constitute a waiver of any of Secured Party's other rights or of
Debtor's obligations hereunder. This Agreement may be amended only by an
instrument in writing executed jointly by Debtor and Secured Party and may be
supplemented only by documents delivered or to be delivered in accordance with
the express terms hereof.

           Section 7.03 Copy as Financing Statement. A photocopy or other
reproduction of this Agreement or any financing statement covering the
Collateral is sufficient as a financing statement, and the same may be filed
with any appropriate filing authority for the purpose of perfecting Secured
Party's security interest in the Collateral.

           Section 7.04 Possession of Collateral. Secured Party shall be deemed
to have possession of any Collateral in transit to it or set apart for it (or,
in either case, any of its agents, affiliates or correspondents).

           Section 7.05 Redelivery of Collateral. If any sale or transfer of
Collateral by Secured Party results in full satisfaction of the Obligations,
and after such sale or transfer and discharge there remains a surplus of
proceeds, Secured Party will deliver to Debtor such excess proceeds in a
commercially reasonable time; provided, however, that neither Secured Party
shall have any liability for any interest, cost or expense in connection with
any delay in delivering such proceeds to Debtor.



<PAGE>


           Section 7.06 Interest. It is the intention of the parties hereto to
conform strictly to usury laws applicable to Secured Party. Accordingly, if the
transactions contemplated hereby would be usurious under applicable state or
federal law, then, notwithstanding anything to the contrary in this Agreement
or in any other agreement entered into in connection with or as security for
the Obligations, it is agreed as follows: (i) the aggregate of all
consideration which constitutes interest under law applicable to Secured Party
that is contracted for, taken, reserved, charged or received under the
Obligations, this Agreement or under any of such other agreements or otherwise
in connection with the Obligations shall under no circumstances exceed the
maximum amount allowed by such applicable law, (ii) in the event that the
maturity of the Obligations is accelerated for any reason, or in the event of
any required or permitted prepayment, then such consideration that constitutes
interest under law applicable to Secured Party may never include more than such
maximum amount, and (iii) excess interest, if any, provided for in this
Agreement or otherwise shall be cancelled automatically and, if theretofore
paid, shall be credited by Secured Party on the principal amount of the
Obligations (or, to the extent that the principal amount of the Obligations
shall have been or would thereby be paid in full, refunded by Secured Party to
Debtor). The right to accelerate the maturity of the Obligations does not
include the right to accelerate any interest which has not otherwise accrued on
the date of such acceleration, and Secured Party does not intend to collect any
unearned interest in the event of acceleration. All sums paid or agreed to be
paid to Secured Party for the use, forbearance or detention of sums included in
the initial Obligations shall, to the extent permitted by applicable law, be
amortized, prorated, allocated and spread throughout the full term of the
Obligations until payment in full so that the rate or amount of interest on
account of the initial Obligations does not exceed the applicable usury
ceiling, if any. To the extent that Article 5069-1.04 of the Texas Revised
Civil Statutes is relevant to Secured Party for the purpose of determining the
Highest Lawful Rate, Secured Party hereby elects to determine the applicable
rate ceiling under such Article by the indicated (weekly) rate ceiling from
time to time in effect, subject to Secured Party's right subsequently to change
such method in accordance with applicable law.

           Section 7.07 Governing Law; Jurisdiction. This Agreement and the
security interest granted hereby shall be construed in accordance with and
governed by the laws of the State of Texas (except to the extent that the laws
of any other jurisdiction govern the perfection and priority of the security
interests granted hereby). Debtor consents to and submits to in personam
jurisdiction and venue in the state district and county courts of the county
wherein Secured Party's offices are located at the address specified in the
opening paragraph hereof, and in the Federal District Courts of the district
wherein such offices of Secured Party are located. This submission to
jurisdiction is nonexclusive and does not preclude Secured Party from obtaining
jurisdiction over Debtor or the Collateral in any court otherwise having
jurisdiction.

           Section 7.08 Subrogation. Until all indebtedness in connection with
the Obligations shall have been paid in full, Debtor shall have no right to
subrogation or to enforce any remedy or participate in any Collateral or
security whatsoever now or hereafter held by Secured Party.

           Section 7.09      Continuing Security Agreement.

           (a) This Agreement shall constitute a continuing security agreement,
and all representations and warranties, covenants and agreements shall, as
applicable, apply to all future as 


<PAGE>


well as existing transactions. Provisions of this Agreement, unless by their
terms exclusive, shall be in addition to other agreements between the parties.

           (b) Except as may be expressly applicable pursuant to Section 9.505
of the Code, no action taken or omission to act by Secured Party hereunder,
including, without limitation, any action taken or inaction pursuant to Section
6.02, shall be deemed to constitute a retention of the Collateral in
satisfaction of the Obligations or otherwise to be in full satisfaction of the
Obligations, and the Obligations shall remain in full force and effect, until
Secured Party shall have applied payments (including, without limitation,
collections from Collateral) towards the Obligations in the full amount then
outstanding or until such subsequent time as is hereinafter provided in
subsection (c) below.

           (c) To the extent that any payments on the Obligations or proceeds
of the Collateral are subsequently invalidated, declared to be fraudulent or
preferential, set aside or required to be repaid to a trustee, debtor in
possession, receiver or other person or entity under any bankruptcy law, common
law or equitable cause, then to such extent the Obligations so satisfied shall
be revived and continue as if such payment or proceeds had not been received by
Secured Party, and Secured Partys' security interests, rights, powers and
remedies hereunder shall continue in full force and effect. In such event, this
Agreement shall be automatically reinstated if it shall theretofore have been
terminated pursuant to Section 7.10.

           (d) In the event that the Obligations are structured such that there
are times when no Indebtedness is owing thereunder, this Agreement shall remain
valid and in full force and effect as to all subsequent indebtedness included
in the Obligations, provided Secured Party has not in the interim period
executed a written release or termination statement or returned possession of
or reassigned the Collateral to Debtor.

           Section 7.10 Termination. The grant of a security interest hereunder
and all of Secured Party's rights, powers and remedies in connection therewith
shall remain in full force and effect until Secured Party has retransferred and
delivered all Collateral in its possession to Debtor, and executed a written
release or termination statement and reassigned to Debtor without recourse or
warranty any remaining Collateral and all rights conveyed hereby. Upon the
complete payment or satisfaction of the Obligations and the compliance by
Debtor with all covenants and agreements hereof, Secured Party, at the written
request and expense of Debtor, will release, reassign and transfer the
Collateral to Debtor and declare this Agreement to be of no further force or
effect. Notwithstanding the foregoing, the provisions of subsection 7.09(c)
shall survive the termination of this Agreement; provided, however, that
Agreement shall terminate upon the Effective Time as defined in that certain
Agreement and Plan of Merger dated as of July 23, 1998, by and among Secured
Party, TBC Radio Acquisition Corp., and Triathlon Broadcasting Company.

           Section 7.11 Counterparts, Effectiveness. This Agreement may be
executed in two or more counterparts, and it shall not be necessary that the
signatures of all parties hereto be contained on any one counterpart hereof.
Each counterpart is deemed an original, but all such counterparts


<PAGE>


taken together constitute one and the same instrument. This Agreement becomes
effective upon the execution hereof by Debtor and delivery of the same to
Secured Party, and it is not necessary for Secured Party to execute any
acceptance hereof or otherwise signify or express its acceptance hereof.

DEBTOR:                                    4630 REALTY, INC.

                                           By:  /s/ Norman Feuer
                                              ---------------------------------
                                           Name:    Norman Feuer
                                           Title:   President/CEO

SECURED PARTY:                             CAPSTAR RADIO BROADCASTING
                                           PARTNERS, INC.

                                           By:  /s/ Kathy Archer
                                              ---------------------------------
                                           Name:    Kathy Archer
                                           Title:   Vice President