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                                                                    EXHIBIT 10.7

                                PLEDGE AGREEMENT


     PLEDGE AGREEMENT (as amended, modified or supplemented from time to time,
this "Agreement"), dated as of March 23, 1999, made by each of the undersigned
pledgors (each a "Pledgor" and, together with any other entity that becomes a
party hereto pursuant to Section 26 hereof, the "Pledgors") to Bankers Trust
Company, as Collateral Agent (the "Pledgee"), for the benefit of the Secured
Creditors (as defined below). Except as otherwise defined herein, capitalized
terms used herein and defined in the Credit Agreement (as defined below) shall
be used herein as therein defined.


                              W I T N E S S E T H:


     WHEREAS, PageMart Wireless, Inc. (the "Borrower"), the lenders from time
to time party thereto (the "Lenders"), Bankers Trust Company, as Administrative
Agent (together with any successor Administrative Agent, the "Administrative
Agent"), Morgan Stanley Senior Funding, Inc., as Syndication Agent, and Bankers
Trust Company and Morgan Stanley Senior Funding, Inc., as Co-Arrangers have
entered into a Credit Agreement, dated as of March 23, 1999 (as amended,
modified or supplemented from time to time, the "Credit Agreement"), providing
for the making of Loans to, and the issuance of Letters of Credit for the
account of, the Borrower as contemplated therein (the Lenders, the
Administrative Agent, the Syndication Agent, the Issuing Lender and the Pledgee
are herein called the "Lender Creditors");

     WHEREAS, the Borrower may at any time and from time to time enter into one
or more Interest Rate Protection Agreements or Other Hedging Agreements with
one or more Lenders or any affiliate thereof (each such Lender or affiliate,
even if the respective Lender subsequently ceases to be a Lender under the
Credit Agreement for any reason, together with such Lender's or affiliate's
successors and assigns, if any, collectively, the "Other Creditors," and
together with the Lender Creditors, the "Secured Creditors");

     WHEREAS, it is a condition to the making of Loans to, and the issuance of
Letters of Credit for the account of, the Borrower under the Credit Agreement
that each Pledgor shall have executed and delivered to the Pledgee this
Agreement; and

     WHEREAS, each Pledgor desires to enter into this Agreement in order to
satisfy the condition described in the preceding paragraph;

     NOW, THEREFORE, in consideration of the foregoing and other benefits
accruing to each Pledgor, the receipt and sufficiency of which are hereby
acknowledged, each Pledgor hereby makes the following representations and
warranties to the Pledgee for the benefit of the Secured Creditors and hereby
covenants and agrees with the Pledgee for the benefit of the Secured Creditors
as follows:

     1. SECURITY FOR OBLIGATIONS. This Agreement is made by each Pledgor for
the benefit of the Secured Creditors to secure:

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          (i) the full and prompt payment when due (whether at the stated
     maturity, by acceleration or otherwise) of all obligations and
     indebtedness (including, without limitation, indemnities, Fees and
     interest thereon) of such Pledgor to the Lender Creditors, whether now
     existing or hereafter incurred under, arising out of, or in connection
     with the Credit Agreement and the other Credit Documents to which such
     Pledgor is a party and the due performance and compliance by such Pledgor
     with all of the terms, conditions and agreements contained in the Credit
     Agreement and in such other Credit Documents (all such obligations and
     liabilities under this clause (i), except to the extent consisting of
     obligations or indebtedness with respect to Interest Rate Protection
     Agreements or Other Hedging Agreements, being herein collectively called
     the "Credit Document Obligations");

          (ii) the full and prompt payment when due (whether at the stated
     maturity, by acceleration or otherwise) of all obligations and liabilities
     owing by such Pledgor to the Other Creditors under, or with respect to,
     any Interest Rate Protection Agreement or Other Hedging Agreement, whether
     such Interest Rate Protection Agreement or Other Hedging Agreement is now
     in existence or hereafter arising, and the due performance and compliance
     by such Pledgor with all of the terms, conditions and agreements contained
     therein (all such obligations and liabilities described in this clause
     (ii) being herein collectively called the "Other Obligations");

          (iii) any and all sums advanced by the Pledgee in order to preserve
     the Collateral (as hereinafter defined) or preserve its security interest
     in the Collateral;

          (iv) in the event of any proceeding for the collection or enforcement
     of any indebtedness, obligations or liabilities of such Pledgor referred
     to in clauses (i), (ii) and (iii) above, after an Event of Default (which
     term to mean and include any Event of Default under, and as defined in,
     the Credit Agreement or any payment default by the Borrower under any
     Interest Rate Protection Agreement or Other Hedging Agreement and shall,
     in any event, include, without limitation, any payment default (after the
     expiration of any applicable grace period) on any of the Obligations (as
     hereinafter defined)) shall have occurred and be continuing, the
     reasonable expenses of retaking, holding, preparing for sale or lease,
     selling or otherwise disposing of or realizing on the Collateral, or of
     any exercise by the Pledgee of its rights hereunder, together with
     reasonable attorneys' fees and court costs; and

          (v) all amounts paid by any Secured Creditor as to which such Secured
     Creditor has the right to reimbursement under Section 11 of this
     Agreement;

     all such obligations, liabilities, sums and expenses set forth in clauses
(i) through (v) of this Section 1 being herein collectively called the
"Obligations," it being acknowledged and agreed that the "Obligations" shall
include extensions of credit of the types described above, whether outstanding
on the date of this Agreement or extended from time to time after the date of
this Agreement.


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     2. DEFINITIONS. (a) Unless otherwise defined herein, all capitalized terms
used herein and defined in the Credit Agreement shall be used herein as therein
defined. Reference to singular terms shall include the plural and vice versa.

     (b) The following capitalized terms used herein shall have the definitions
specified below:

     "Administrative Agent" has the meaning set forth in the Recitals hereto.

     "Adverse Claim" has the meaning given such term in Section 8-102(a)(1) of
the UCC.

     "Agreement" has the meaning set forth in the first paragraph hereof.

     "Certificated Security" has the meaning given such term in Section
8-102(a)(4) of the UCC.

     "Clearing Corporation" has the meaning given such term in Section
8-102(a)(5) of the UCC.

     "Collateral" has the meaning set forth in Section 3.1 hereof.

     "Collateral Accounts" means any and all accounts established and
maintained by the Pledgee in the name of any Pledgor to which Collateral may be
credited.

     "Credit Agreement" has the meaning set forth in the Recitals hereto.

     "Credit Document Obligations" has the meaning set forth in Section 1
hereof.

     "Domestic Corporation" has the meaning set forth in the definition of
"Stock."

     "Event of Default" has the meaning set forth in Section 1 hereof.

     "Financial Asset" has the meaning given such term in Section 8-102(a)(9)
of the UCC.

     "Foreign Corporation" has the meaning set forth in the definition of
"Stock."

     "Indemnitees" has the meaning set forth in Section 11 hereof.

     "Instrument" has the meaning given such term in Section 9-105(1)(i) of the
UCC.

     "Investment Property" has the meaning given such term in Section 9-115(f)
of the UCC.

     "Lender Creditors" has the meaning set forth in the Recitals hereto.

     "Lenders" has the meaning set forth in the Recitals hereto.


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     "Limited Liability Company Assets" means all assets, whether tangible or
intangible and whether real, personal or mixed (including, without limitation,
all limited liability company capital and interest in other limited liability
companies), at any time owned or represented by any Limited Liability Company
Interest.

     "Limited Liability Company Interests" means the entire limited liability
company membership interest at any time owned by any Pledgor in any limited
liability company.

     "Non-Voting Stock" means all capital stock which is not Voting Stock.

     "Notes" means all intercompany notes among the Borrower and its
Subsidiaries and all other promissory notes from time to time issued to, or
held by, any Pledgor, provided that any such promissory note issued by an
executive officer of any Pledgor may be excluded from this definition so long
as the aggregate principal amount of such note does not exceed $500,000.

     "Obligations" has the meaning set forth in Section 1 hereof.

     "Other Creditors" has the meaning set forth in the Recitals hereto.

     "Other Obligations" has the meaning set forth in Section 1 hereof.

     "Partnership Assets" means all assets, whether tangible or intangible and
whether real, personal or mixed (including, without limitation, all partnership
capital and interest in other partnerships), at any time owned or represented
by any Partnership Interest.

     "Partnership Interest" means the entire general partnership interest or
limited partnership interest at any time owned by any Pledgor in any general
partnership or limited partnership.

     "Pledged Notes" has the meaning set forth in Section 3.5 hereof.

     "Pledgee" has the meaning set forth in the first paragraph hereof.

     "Pledgor" has the meaning set forth in the first paragraph hereof.

     "Proceeds" has the meaning given such term in Section 9-306(l) of the UCC.

     "Required Lenders" has the meaning given such term in the Credit
Agreement.

     "Secured Creditors" has the meaning set forth in the Recitals hereto.

     "Secured Debt Agreements" has the meaning set forth in Section 5 hereof.

     "Securities Account" has the meaning given such term in Section 8-501(a)
of the UCC.

     "Securities Act" means the Securities Act of 1933, as amended, as in
effect from time to time.


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     "Security" and "Securities" has the meaning given such term in Section
8-102(a)(15) of the UCC and shall in any event include all Stock and Notes (to
the extent same constitute "Securities" under Section 8-102(a)(15)).

     "Security Entitlement" has the meaning given such term in Section
8-102(a)(17) of the UCC.

     "Stock" means (x) with respect to corporations incorporated under the laws
of the United States or any State or territory thereof (each a "Domestic
Corporation"), all of the issued and outstanding shares of capital stock of any
corporation at any time owned by any Pledgor of any Domestic Corporation and
(y) with respect to corporations not Domestic Corporations (each a "Foreign
Corporation"), all of the issued and outstanding shares of capital stock at any
time owned by any Pledgor of any Foreign Corporation.

     "Termination Date" has the meaning set forth in Section 21 hereof.

     "UCC" means the Uniform Commercial Code as in effect in the State of New
York from time to time; provided that all references herein to specific
sections or subsections of the UCC are references to such sections or
subsections, as the case may be, of the Uniform Commercial Code as in effect in
the State of New York on the date hereof. "Uncertificated Security" has the
meaning given such term in Section 8-102(a)(18) of the UCC.

     "Voting Stock" means all classes of capital stock of any Foreign
Corporation entitled to vote.

     3. PLEDGE OF SECURITIES, ETC.

     3.1 Pledge. To secure the Obligations now or hereafter owed or to be
performed by such Pledgor, each Pledgor does hereby grant, pledge and assign to
the Pledgee for the benefit of the Secured Creditors, and does hereby create a
continuing security interest in favor of the Pledgee for the benefit of the
Secured Creditors in, all of the right, title and interest in and to the
following, whether now existing or hereafter from time to time acquired
(collectively, the "Collateral"):

          (a) each of the Collateral Accounts, including any and all assets of
     whatever type or kind deposited by such Pledgor in such Collateral
     Account, whether now owned or hereafter acquired, existing or arising,
     including, without limitation, all Financial Assets, Investment Property,
     moneys, checks, drafts, Instruments, Securities or interests therein of
     any type or nature deposited or required by the Credit Agreement or any
     other Secured Debt Agreement to be deposited in such Collateral Account,
     and all investments and all certificates and other Instruments (including
     depository receipts, if any) from time to time representing or evidencing
     the same, and all dividends, interest, distributions, cash and other
     property from time to time received, receivable or otherwise distributed
     in respect of or in exchange for any or all of the foregoing;


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          (b) all Securities of such Pledgor from time to time;

          (c) all Limited Liability Company Interests of such Pledgor from time
     to time and all of its right, title and interest in each limited liability
     company to which each such interest relates, whether now existing or
     hereafter acquired, including, without limitation:

               (A) all the capital thereof and its interest in all profits,
          losses, Limited Liability Company Assets and other distributions to
          which such Pledgor shall at any time be entitled in respect of such
          Limited Liability Company Interests;

               (B) all other payments due or to become due to such Pledgor in
          respect of Limited Liability Company Interests, whether under any
          limited liability company agreement, operating agreement or
          otherwise, whether as contractual obligations, damages, insurance
          proceeds or otherwise;

               (C) all of its claims, rights, powers, privileges, authority,
          options, security interests, liens and remedies, if any, under any
          limited liability company agreement or operating agreement, or at law
          or otherwise in respect of such Limited Liability Company Interests;

               (D) all present and future claims, if any, of such Pledgor
          against any such limited liability company for moneys loaned or
          advanced, for services rendered or otherwise;

               (E) all of such Pledgor's rights under any limited liability
          company agreement or operating agreement or at law to exercise and
          enforce every right, power, remedy, authority, option and privilege
          of such Pledgor relating to such Limited Liability Company Interests,
          including any power to terminate, cancel or modify any limited
          liability company agreement or operating agreement, to execute any
          instruments and to take any and all other action on behalf of and in
          the name of any of such Pledgor in respect of such Limited Liability
          Company Interests and any such limited liability company, to make
          determinations, to exercise any election (including, but not limited
          to, election of remedies) or option or to give or receive any notice,
          consent, amendment, waiver or approval, together with full power and
          authority to demand, receive, enforce, collect or receipt for any of
          the foregoing or for any Limited Liability Company Asset, to enforce
          or execute any checks, or other instruments or orders, to file any
          claims and to take any action in connection with any of the foregoing
          (with all of the foregoing rights only to be exercisable upon the
          occurrence and during the continuation of an Event of Default); and

               (F) all other property hereafter delivered in substitution for
          or in addition to any of the foregoing, all certificates and
          instruments representing or evidencing such other property and all
          cash, securities, interest, dividends, rights and other property at
          any time and from time to time received, receivable or otherwise
          distributed in respect of or in exchange for any or all thereof;


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          (d) all Partnership Interests of such Pledgor from time to time and
     all of its right, title and interest in each partnership to which each
     such interest relates, whether now existing or hereafter acquired,
     including, without limitation:

               (A) all the capital thereof and its interest in all profits,
          losses, Partnership Assets and other distributions to which such
          Pledgor shall at any time be entitled in respect of such Partnership
          Interests;

               (B) all other payments due or to become due to such Pledgor in
          respect of Partnership Interests, whether under any partnership
          agreement, operating agreement or otherwise, whether as contractual
          obligations, damages, insurance proceeds or otherwise;

               (C) all of its claims, rights, powers, privileges, authority,
          options, security interests, liens and remedies, if any, under any
          partnership agreement or operating agreement, or at law or otherwise
          in respect of such Partnership Interests;

               (D) all present and future claims, if any, of such Pledgor
          against any such partnership for moneys loaned or advanced, for
          services rendered or otherwise;

               (E) all of such Pledgor's rights under any partnership agreement
          or operating agreement or at law to exercise and enforce every right,
          power, remedy, authority, option and privilege of such Pledgor
          relating to such Partnership Interests, including any power to
          terminate, cancel or modify any partnership agreement or operating
          agreement, to execute any instruments and to take any and all other
          action on behalf of and in the name of any of such Pledgor in respect
          of such Partnership Interests and any such partnership, to make
          determinations, to exercise any election (including, but not limited
          to, election of remedies) or option or to give or receive any notice,
          consent, amendment, waiver or approval, together with full power and
          authority to demand, receive, enforce, collect or receipt for any of
          the foregoing or for any Partnership Asset, to enforce or execute any
          checks, or other instruments or orders, to file any claims and to
          take any action in connection with any of the foregoing (with all of
          the foregoing rights only to be exercisable upon the occurrence and
          during the continuation of an Event of Default); and

               (F) all other property hereafter delivered in substitution for
          or in addition to any of the foregoing, all certificates and
          instruments representing or evidencing such other property and all
          cash, securities, interest, dividends, rights and other property at
          any time and from time to time received, receivable or otherwise
          distributed in respect of or in exchange for any or all thereof;

          (e) all Security Entitlements of such Pledgor from time to time in
     any and all of the foregoing;


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          (f) all Financial Assets and Investment Property of such Pledgor from
     time to time; and

          (g) all Proceeds of any and all of the foregoing.

     Notwithstanding anything to the contrary contained in this Section 3.1,
(x) no Pledgor (to the extent that it is the Borrower or a Domestic Subsidiary
of the Borrower) shall be required at any time to pledge hereunder more than
65% of the Voting Stock of any Foreign Corporation and (y) each Pledgor shall
be required to pledge hereunder 100% of any Non-Voting Stock at any time and
from time to time acquired by such Pledgor of any Foreign Corporation.

     3.2. Procedures. (a) To the extent that any Pledgor at any time or from
time to time owns, acquires or obtains any right, title or interest in any
Collateral, such Collateral shall automatically (and without the taking of any
action by the respective Pledgor) be pledged pursuant to Section 3.1 of this
Agreement and, in addition thereto, such Pledgor shall (to the extent provided
below) take the following actions as set forth below (as promptly as
practicable and, in any event, within 10 Business Days after it obtains such
Collateral) for the benefit of the Pledgee and the Secured Creditors:

          (i) with respect to a Certificated Security (other than a
     Certificated Security credited on the books of a Clearing Corporation),
     the respective Pledgor shall physically deliver such Certificated Security
     to the Pledgee, endorsed to the Pledgee or endorsed in blank;

          (ii) with respect to an Uncertificated Security (other than an
     Uncertificated Security credited on the books of a Clearing Corporation),
     the respective Pledgor shall cause the issuer of such Uncertificated
     Security to duly authorize and execute, and deliver to the Pledgee, an
     agreement for the benefit of the Pledgee and the Secured Creditors
     substantially in the form of Annex G hereto (appropriately completed to
     the reasonable satisfaction of the Pledgee and with such modifications, if
     any, as shall be reasonably satisfactory to the Pledgee) pursuant to which
     such issuer agrees to comply with any and all instructions originated by
     the Pledgee without further consent by the registered owner and not to
     comply with instructions regarding such Uncertificated Security (and any
     Partnership Interests and Limited Liability Company Interests issued by
     such issuer) originated by any other Person other than a court of
     competent jurisdiction;

          (iii) with respect to a Certificated Security, Uncertificated
     Security, Partnership Interest or Limited Liability Company Interest
     credited on the books of a Clearing Corporation (including a Federal
     Reserve Bank, Participants Trust Company or The Depository Trust Company),
     the respective Pledgor shall promptly notify the Pledgee thereof and shall
     promptly take all actions required (i) to comply with the applicable rules
     of such Clearing Corporation and (ii) to perfect the security interest of
     the Pledgee under applicable law (including, in any event, under Sections
     9-115 (4)(a) and (b), 9-115 (1)(e) and 8-106 (d) of the UCC). The Pledgor
     further agrees to take such actions as the Pledgee deems necessary or
     desirable to effect the foregoing;


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<PAGE>   9

          (iv) with respect to a Partnership Interest or a Limited Liability
     Company Interest (other than a Partnership Interest or Limited Liability
     Interest credited on the books of a Clearing Corporation), (1) if such
     Partnership Interest or Limited Liability Company Interest is represented
     by a certificate, the procedure set forth in Section 3.2(a)(i) hereof, and
     (2) if such Partnership Interest or Limited Liability Company Interest is
     not represented by a certificate, the procedure set forth in Section
     3.2(a)(ii) hereof;

          (v) with respect to any Note, physical delivery of such Note to the
     Pledgee, endorsed to the Pledgee or endorsed in blank; and

          (vi) with respect to cash, (i) upon the request of the Pledgee,
     establishment by the Pledgee of a cash account in the name of such Pledgor
     over which the Pledgee shall have exclusive and absolute control and
     dominion (and no withdrawals or transfers may be made therefrom by any
     Person except with the prior written consent of the Pledgee) and (ii)
     deposit of such cash in such cash account.

     (b) In addition to the actions required to be taken pursuant to proceeding
Section 3.2(a) hereof, each Pledgor shall take the following additional actions
with respect to the Securities and Collateral (as defined below):

          (i) with respect to all Collateral of such Pledgor whereby or with
     respect to which the Pledgee may obtain "control" thereof within the
     meaning of Section 8-106 of the UCC (or under any provision of the UCC as
     same may be amended or supplemented from time to time, or under the laws
     of any relevant State other than the State of New York), the respective
     Pledgor shall take all actions as may be requested from time to time by
     the Pledgee so that "control" of such Collateral is obtained and at all
     times held by the Pledgee; and

          (ii) each Pledgor shall from time to time cause appropriate financing
     statements (on Form UCC-1 or other appropriate form) under the Uniform
     Commercial Code as in effect in the various relevant States, covering all
     Collateral hereunder (with the form of such financing statements to be
     satisfactory to the Pledgee), to be filed in the relevant filing offices
     so that at all times the Pledgee has a security interest in all Investment
     Property and other Collateral which is perfected by the filing of such
     financing statements (in each case to the maximum extent perfection by
     filing may be obtained under the laws of the relevant States, including,
     without limitation, Section 9-115(4)(b) of the UCC).

     3.3 Subsequently Acquired Collateral. If any Pledgor shall acquire (by
purchase, stock dividend or otherwise) any additional Collateral at any time or
from time to time after the date hereof, such Collateral shall automatically
(and without any further action being required to be taken) be subject to the
pledge and security interests created pursuant to Section 3.1 hereof and,
furthermore, the Pledgor will promptly thereafter take (or cause to be taken)
all action with respect to such Collateral in accordance with the procedures
set forth in Section 3.2 hereof, and will promptly thereafter deliver to the
Pledgee (i) a certificate executed by a principal executive officer of such
Pledgor describing such Collateral and certifying that the same has been duly
pledged in favor of the Pledgee (for the benefit of the Secured Creditors)
hereunder and (ii) 


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supplements to Annexes A through F hereto as are necessary to cause such
annexes to be complete and accurate at such time. Without limiting the
foregoing, each Pledgor shall be required to pledge hereunder any shares of
stock at any time and from time to time after the date hereof acquired by such
Pledgor of any Foreign Corporation, provided that (x) no Pledgor (to the extent
that it is the Borrower or a Domestic Subsidiary of the Borrower) shall be
required at any time to pledge hereunder more than 65% of the Voting Stock of
any Foreign Corporation and (y) each Pledgor shall be required to pledge
hereunder 100% of any Non-Voting Stock at any time and from time to time
acquired by such Pledgor of any Foreign Corporation.

     3.4 Transfer Taxes. Each pledge of Collateral under Section 3.1 or Section
3.3 hereof shall be accompanied by any transfer tax stamps required in
connection with the pledge of such Collateral.

     3.5 Definition of Pledged Notes. All Notes at any time pledged or required
to be pledged hereunder are hereinafter called the "Pledged Notes".

     3.6 Certain Representations and Warranties Regarding the Collateral. Each
Pledgor represents and warrants that on the date hereof (i) each Subsidiary of
such Pledgor, and the direct ownership thereof, is listed in Annex A hereto;
(ii) the Stock held by such Pledgor consists of the number and type of shares
of the stock of the corporations as described in Annex B hereto; (iii) such
Stock constitutes that percentage of the issued and outstanding capital stock
of the issuing corporation as is set forth in Annex B hereto; (iv) the Notes
held by such Pledgor consist of the promissory notes described in Annex C
hereto where such Pledgor is listed as the lender; (v) the Limited Liability
Company Interests held by such Pledgor consist of the number and type of
interests of the Persons described in Annex D hereto; (vi) each such Limited
Liability Company Interest constitutes that percentage of the issued and
outstanding equity interest of the issuing Person as set forth in Annex D
hereto; (vii) the Partnership Interests held by such Pledgor consist of the
number and type of interests of the Persons described in Annex E hereto; (viii)
each such Partnership Interest constitutes that percentage or portion of the
entire partnership interest of the Partnership as set forth in Annex E hereto;
(ix) the Pledgor has complied with the respective procedure set forth in
Section 3.2(a) hereof with respect to each item of Collateral described in
Annexes A through E hereto; and (x) on the date hereof, such Pledgor owns no
other Securities, Limited Liability Company Interests or Partnership Interests.

     4. APPOINTMENT OF SUB-AGENTS; ENDORSEMENTS, ETC. If and to the extent
necessary to enable the Pledgee to perfect its security interest in any of the
Collateral or to exercise any of its remedies hereunder, the Pledgee shall have
the right to appoint one or more sub-agents for the purpose of retaining
physical possession of the Collateral, which may be held (in the discretion of
the Pledgee) in the name of the relevant Pledgor, endorsed or assigned in blank
or in favor of the Pledgee or any nominee or nominees of the Pledgee or a
sub-agent appointed by the Pledgee.

     5. VOTING, ETC., WHILE NO EVENT OF DEFAULT. Unless and until there shall
have occurred and be continuing an Event of Default, each Pledgor shall be
entitled to exercise any and all voting and other consensual rights pertaining
to the Collateral owned by it, and to give consents, waivers or ratifications
in respect thereof; provided, that, in each case, no vote shall


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be cast or any consent, waiver or ratification given or any action taken or
omitted to be taken which would violate or be inconsistent with any of the
terms of this Agreement, the Credit Agreement, any other Credit Document or any
Interest Rate Protection Agreement or Other Hedging Agreement (collectively,
the "Secured Debt Agreements"), or which would have the effect of impairing the
value of the Collateral or any part thereof or the position or interests of the
Pledgee or any other Secured Creditor in the Collateral. All such rights of
each Pledgor to vote and to give consents, waivers and ratifications shall
cease in case an Event of Default has occurred and is continuing, and Section 7
hereof shall become applicable.

     6. DIVIDENDS AND OTHER DISTRIBUTIONS. Unless and until there shall have
occurred and be continuing an Event of Default, all cash dividends, cash
distributions, cash Proceeds and other cash amounts payable in respect of the
Collateral shall be paid to the respective Pledgor (and may be used by such
Pledgor for its general corporate purposes). The Pledgee shall be entitled to
receive directly, and to retain as part of the Collateral:

          (i) all other or additional stock, notes, limited liability company
     interests, partnership interests, instruments or other securities or
     property (including cash dividends except as otherwise provided above)
     paid or distributed by way of dividend or otherwise in respect of the
     Collateral;

          (ii) all other or additional stock, notes, limited liability company
     interests, partnership interests, instruments or other securities or
     property (including, but not limited to, cash except as otherwise provided
     above) paid or distributed in respect of the Collateral by way of
     stock-split, spin-off, split-up, reclassification, combination of shares
     or similar rearrangement; and

          (iii) all other or additional stock, notes, limited liability company
     interests, partnership interests, instruments or other securities or
     property (including, but not limited to, cash except as otherwise provided
     above) which may be paid in respect of the Collateral by reason of any
     consolidation, merger, exchange of stock, conveyance of assets,
     liquidation or similar corporate reorganization.

Nothing contained in this Section 6 shall limit or restrict in any way the
Pledgee's right to receive proceeds of the Collateral in any form in accordance
with Section 3 of this Agreement. All dividends, distributions or other
payments which are received by any Pledgor contrary to the provisions of this
Section 6 and Section 7 hereof shall be received in trust for the benefit of
the Pledgee, shall be segregated from other property or funds of such Pledgor
and shall be forthwith paid over to the Pledgee as Collateral in the same form
as so received (with any necessary endorsement).

     7. REMEDIES IN CASE OF EVENT OF DEFAULT. If there shall have occurred and
be continuing an Event of Default, then and in every such case, the Pledgee
shall be entitled to exercise all of the rights, powers and remedies (whether
vested in it by this Agreement, any other Secured Debt Agreement or by law) for
the protection and enforcement of its rights in respect of the Collateral, and
the Pledgee shall be entitled to exercise all the rights and remedies of a
secured party under the Uniform Commercial Code as in effect in any relevant
jurisdiction and 


                                     -11-
<PAGE>   12

also shall be entitled, without limitation, to exercise the following rights,
which each Pledgor hereby agrees to be commercially reasonable:

          (i) to receive all amounts payable in respect of the Collateral
     otherwise payable under Section 6 hereof to the respective Pledgor;

          (ii) subject to receipt of any approvals required under the
     Communications Act or the FCC Rules as provided in Section 19 hereof, to
     transfer all or any part of the Collateral into the Pledgee's name or the
     name of its nominee or nominees;

          (iii) to accelerate, subject to the terms thereof, any Pledged Note
     which may be accelerated in accordance with its terms, and take any other
     lawful action to collect upon any Pledged Note (including, without
     limitation, to make any demand for payment thereon of any amounts then due
     and payable);

          (iv) subject to receipt of any approvals required under the
     Communications Act or the FCC Rules as provided in Section 19 hereof, to
     vote all or any part of the Collateral (whether or not transferred into
     the name of the Pledgee) and give all consents, waivers and ratifications
     in respect of the Collateral and otherwise act with respect thereto as
     though it were the outright owner thereof (each Pledgor hereby irrevocably
     constituting and appointing the Pledgee the proxy and attorney-in-fact of
     such Pledgor, with full power of substitution to do so);

          (v) at any time and from time to time to sell, assign and deliver, or
     grant options to purchase, all or any part of the Collateral, or any
     interest therein, at any public or private sale, without demand of
     performance, advertisement or notice of intention to sell or of the time
     or place of sale or adjournment thereof or to redeem or otherwise (all of
     which are hereby waived by each Pledgor), for cash, on credit or for other
     property, for immediate or future delivery without any assumption of
     credit risk, and for such price or prices and on such terms as the Pledgee
     in its absolute discretion may determine, provided that at least 10 days'
     written notice of the time and place of any such sale shall be given to
     the respective Pledgor. The Pledgee shall not be obligated to make any
     such sale of Collateral regardless of whether any such notice of sale has
     theretofore been given. Each Pledgor hereby waives and releases to the
     fullest extent permitted by law any right or equity of redemption with
     respect to the Collateral, whether before or after sale hereunder, and all
     rights, if any, of marshaling the Collateral and any other security for
     the Obligations or otherwise. At any such sale, unless prohibited by
     applicable law, the Pledgee on behalf of the Secured Creditors may bid for
     and purchase all or any part of the Collateral so sold free from any such
     right or equity of redemption. Neither the Pledgee nor any other Secured
     Creditor shall be liable for failure to collect or realize upon any or all
     of the Collateral or for any delay in so doing nor shall any of them be
     under any obligation to take any action whatsoever with regard thereto;
     and

          (vi) to set-off any and all Collateral against any and all
     Obligations, and to withdraw any and all cash or other Collateral from any
     and all Collateral Accounts and to apply such cash and other Collateral to
     the payment of any and all Obligations.


                                     -12-
<PAGE>   13

     8. REMEDIES, ETC., CUMULATIVE. Each and every right, power and remedy of
the Pledgee provided for in this Agreement or in any other Secured Debt
Agreement, or now or hereafter existing at law or in equity or by statute shall
be cumulative and concurrent and shall be in addition to every other such
right, power or remedy. The exercise or beginning of the exercise by the
Pledgee or any other Secured Creditor of any one or more of the rights, powers
or remedies provided for in this Agreement or any other Secured Debt Agreement
or now or hereafter existing at law or in equity or by statute or otherwise
shall not preclude the simultaneous or later exercise by the Pledgee or any
other Secured Creditor of all such other rights, powers or remedies, and no
failure or delay on the part of the Pledgee or any other Secured Creditor to
exercise any such right, power or remedy shall operate as a waiver thereof. No
notice to or demand on any Pledgor in any case shall entitle it to any other or
further notice or demand in similar or other circumstances or constitute a
waiver of any of the rights of the Pledgee or any other Secured Creditor to any
other or further action in any circumstances without notice or demand. The
Secured Creditors agree that this Agreement may be enforced only by the action
of the Administrative Agent or the Pledgee, in each case acting upon the
instructions of the Required Lenders (or, after the date on which all Credit
Document Obligations have been paid in full, the holders of at least the
majority of the outstanding Other Obligations) and that no other Secured
Creditor shall have any right individually to seek to enforce or to enforce
this Agreement or to realize upon the security to be granted hereby, it being
understood and agreed that such rights and remedies may be exercised by the
Administrative Agent or the Pledgee or the holders of at least a majority of
the outstanding Other Obligations, as the case may be, for the benefit of the
Secured Creditors upon the terms of this Agreement.

     9. APPLICATION OF PROCEEDS. (a) All monies collected by the Pledgee upon
any sale or other disposition of the Collateral pursuant to the terms of this
Agreement, together with all other monies received by the Pledgee hereunder,
shall be applied in the manner provided in the Security Agreement.

     (b) It is understood and agreed that the Pledgors shall remain jointly and
severally liable to the extent of any deficiency between the amount of the
proceeds of the Collateral hereunder and the aggregate amount of the
Obligations.

     10. PURCHASERS OF COLLATERAL. Upon any sale of the Collateral by the
Pledgee hereunder (whether by virtue of the power of sale herein granted,
pursuant to judicial process or otherwise), the receipt of the Pledgee or the
officer making the sale shall be a sufficient discharge to the purchaser or
purchasers of the Collateral so sold, and such purchaser or pur-chasers shall
not be obligated to see to the application of any part of the purchase money
paid over to the Pledgee or such officer or be answerable in any way for the
misapplication or nonapplication thereof.

     11. INDEMNITY. Each Pledgor jointly and severally agrees (i) to indemnify
and hold harmless the Pledgee in such capacity and each other Secured Creditor
and their respective successors, assigns, employees, agents, affiliates and
servants (individually an "Indemnitee," and collectively the "Indemnitees")
from and against any and all claims, demands, losses, judgments and liabilities
(including liabilities for penalties) of whatsoever kind or nature, and (ii) to
reimburse each Indemnitee for all costs and expenses, including reasonable
attorneys' fees, in each case 


                                     -13-
<PAGE>   14

growing out of or resulting from this Agreement or the exercise by any
Indemnitee of any right or remedy granted to it hereunder or under any other
Secured Debt Agreement (but excluding any claims, demands, losses, judgments
and liabilities or expenses to the extent incurred by reason of gross
negligence or willful misconduct of such Indemnitee as finally determined by a
court of competent jurisdiction). In no event shall the Pledgee be liable, in
the absence of gross negligence or willful misconduct on its part, for any
matter or thing in connection with this Agreement other than to account for
monies actually received by it in accordance with the terms hereof. If and to
the extent that the obligations of any Pledgor under this Section 11 are
unenforceable for any reason, such Pledgor hereby agrees to make the maximum
contribution to the payment and satisfaction of such obligations which is
permissible under applicable law.

     12. PLEDGEE NOT A PARTNER OR LIMITED LIABILITY COMPANY MEMBER. (a) Nothing
herein shall be construed to make the Pledgee or any other Secured Creditor
liable as a member of any limited liability company or as a partner of any
partnership and neither the Pledgee nor any other Secured Creditor by virtue of
this Agreement or otherwise (except as referred to in the following sentence)
shall have any of the duties, obligations or liabilities of a member of any
limited liability company or of a partner of any partnership. The parties
hereto expressly agree that, unless the Pledgee shall become the absolute owner
of Collateral consisting of a Limited Liability Company Interest or Partnership
Interest pursuant hereto, this Agreement shall not be construed as creating a
partnership or joint venture among the Pledgee, any other Secured Creditor
and/or any Pledgor.

     (b) Except as provided in the last sentence of paragraph (a) of this
Section 12, the Pledgee, by accepting this Agreement, did not intend to become
a member of any limited liability company or a partner of any partnership or
otherwise be deemed to be a co-venturer with respect to any Pledgor or any
limited liability company or partnership either before or after an Event of
Default shall have occurred. The Pledgee shall have only those powers set forth
herein and the Secured Creditors shall assume none of the duties, obligations
or liabilities of a member of any limited liability company or of a partner of
any partnership or any Pledgor except as provided in the last sentence of
paragraph (a) of this Section 12.

     (c) The Pledgee and the other Secured Creditors shall not be obligated to
perform or discharge any obligation of any Pledgor as a result of the pledge
hereby effected.

     (d) The acceptance by the Pledgee of this Agreement, with all the rights,
powers, privileges and authority so created, shall not at any time or in any
event obligate the Pledgee or any other Secured Creditor to appear in or defend
any action or proceeding relating to the Collateral to which it is not a party,
or to take any action hereunder or thereunder, or to expend any money or incur
any expenses or perform or discharge any obligation, duty or liability under
the Collateral.

     13. FURTHER ASSURANCES; POWER-OF-ATTORNEY. (a) Each Pledgor agrees that it
will join with the Pledgee in executing and, at such Pledgor's own expense,
file and refile under the Uniform Commercial Code or other applicable law such
financing statements, continuation statements and other documents in such
offices as the Pledgee may deem necessary and wherever required by law in order
to perfect and preserve the Pledgee's security interest in


                                     -14-
<PAGE>   15

the Collateral and hereby authorizes the Pledgee to file financing statements
and amendments thereto relative to all or any part of the Collateral without
the signature of such Pledgor where permitted by law, and agrees to do such
further acts and things and to execute and deliver to the Pledgee such
additional conveyances, assignments, agreements and instruments as the Pledgee
may reasonably require or deem necessary to carry into effect the purposes of
this Agreement or to further assure and confirm unto the Pledgee its rights,
powers and remedies hereunder.

     (b) Subject to the Communications Act and the FCC Rules to the extent
applicable, each Pledgor hereby appoints the Pledgee such Pledgor's
attorney-in-fact, with full authority in the place and stead of such Pledgor
and in the name of such Pledgor or otherwise, to act from time to time solely
after the occurrence and during the continuance of an Event of Default in the
Pledgee's reasonable discretion to take any action and to execute any
instrument which the Pledgee may deem necessary or advisable to accomplish the
purposes of this Agreement.

     (c) Each Pledgor agrees that, in the event of any change in any
requirement of law occurring after the date hereof that affects in any manner
the Pledgee's rights of access to, or use or sale of the FCC Licenses or the
procedures necessary to enable the Pledgee to obtain such rights of access, use
or sale (including, without limitation, changes allowing greater such access),
each Pledgor upon request of the Pledgee or the Required Lenders, shall enter
into an amendment to this Agreement in form and substance satisfactory to the
Pledgee to provide the Pledgee and the Secured Creditors with such rights to
the greatest extent possible consistent with then applicable requirements of
law, including without limitation the Communications Act and the FCC Rules.

     14. THE PLEDGEE AS AGENT. The Pledgee will hold in accordance with this
Agreement all items of the Collateral at any time received under this
Agreement. It is expressly understood and agreed by each Secured Creditor that
by accepting the benefits of this Agreement each such Secured Creditor
acknowledges and agrees that the obligations of the Pledgee as holder of the
Collateral and interests therein and with respect to the disposition thereof,
and otherwise under this Agreement, are only those expressly set forth in this
Agreement. The Pledgee shall act hereunder on the terms and conditions set
forth herein and in Section 12 of the Credit Agreement.

     15. TRANSFER BY THE PLEDGORS. No Pledgor will sell or otherwise dispose
of, grant any option with respect to, or mortgage, pledge or otherwise encumber
any of the Collateral or any interest therein (except as may be permitted in
accordance with the terms of the Credit Agreement).

     16. REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE PLEDGORS. (a) Each
Pledgor represents, warrants and covenants that:

          (i) it is the legal, beneficial and record owner of, and has good and
     marketable title to, all Collateral consisting of one or more Securities
     and that it has sufficient interest in all Collateral in which a security
     interest is purported to be created hereunder for such security interest
     to attach (subject, in each case, to no pledge, lien, mortgage,


                                     -15-
<PAGE>   16

     hypothecation, security interest, charge, option, Adverse Claim or other
     encumbrance whatsoever, except the liens and security interests created by
     this Agreement);

          (ii) it has full power, authority and legal right to pledge all the
     Collateral pledged by it pursuant to this Agreement;

          (iii) this Agreement has been duly authorized, executed and delivered
     by such Pledgor and constitutes a legal, valid and binding obligation of
     such Pledgor enforceable against such Pledgor in accordance with its
     terms, except to the extent that the enforceability hereof may be limited
     by applicable bankruptcy, insolvency, reorganization, moratorium or other
     similar laws generally affecting creditors' rights and by equitable
     principles (regardless of whether enforcement is sought in equity or at
     law);

          (iv) except to the extent already obtained or made, no consent of any
     other party (including, without limitation, any stockholder, partner,
     member or creditor of such Pledgor or any of its Subsidiaries) and no
     consent, license, permit, approval or authorization of, exemption by,
     notice or report to, or registration, filing or declaration with, any
     governmental authority is required to be obtained by such Pledgor in
     connection with (a) the execution, delivery or performance of this
     Agreement, (b) the validity or enforceability of this Agreement (except as
     set forth in clause (iii) above), (c) the perfection or enforceability of
     the Pledgee's security interest in the Collateral or (d) except for
     compliance with or as may be required by applicable securities laws, the
     exercise by the Pledgee of any of its rights or remedies provided herein;

          (v) the execution, delivery and performance of this Agreement will
     not violate any provision of any applicable law or regulation or of any
     order, judgment, writ, award or decree of any court, arbitrator or
     governmental authority, domestic or foreign, applicable to such Pledgor,
     or of the certificate of incorporation, operating agreement, limited
     liability company agreement, partnership agreement or by-laws of such
     Pledgor or of any securities issued by such Pledgor or any of its
     Subsidiaries, or of any mortgage, deed of trust, indenture, lease, loan
     agreement, credit agreement or other material contract, agreement or
     instrument or undertaking to which such Pledgor or any of its Subsidiaries
     is a party or which purports to be binding upon such Pledgor or any of its
     Subsidiaries or upon any of their respective assets and will not result in
     the creation or imposition of (or the obligation to create or impose) any
     lien or encumbrance on any of the assets of such Pledgor or any of its
     Subsidiaries except as contemplated by this Agreement;

          (vi) all of the Collateral (consisting of Securities, Limited
     Liability Company Interests or Partnership Interests) has been duly and
     validly issued and acquired, is fully paid and non-assessable and is
     subject to no options to purchase or similar rights;

          (vii) the pledge, collateral assignment and delivery to the Pledgee
     of the Collateral consisting of Certificated Securities (together with
     instruments of transfer therefor) pursuant to this Agreement creates a
     valid and perfected first priority security interest in such Certificated
     Securities, and the proceeds thereof, subject to no prior Lien or
     encumbrance or to any agreement purporting to grant to any third party a
     Lien or 


                                     -16-
<PAGE>   17

     encumbrance on the property or assets of such Pledgor which would include
     the Securities, and the Pledgee is entitled to all the rights, priorities
     and benefits afforded by the UCC or other relevant law as enacted in any
     relevant jurisdiction to perfect security interests in respect of such
     Collateral; and

          (viii) "control" (as defined in Section 8-106 of the UCC) has been
     obtained by the Pledgee over all Collateral consisting of Securities
     (including Notes which are Securities) with respect to which such
     "control" may be obtained pursuant to Section 8-106 of the UCC.

     (b) Each Pledgor covenants and agrees that it will defend the Pledgee's
right, title and security interest in and to the Securities and the proceeds
thereof against the claims and demands of all persons whomsoever; and each
Pledgor covenants and agrees that it will have like title to and right to
pledge any other property at any time hereafter pledged to the Pledgee as
Collateral hereunder and will likewise defend the right thereto and security
interest therein of the Pledgee and the other Secured Creditors.

     (c) Each Pledgor covenants and agrees that it will take no action which
would violate any of the terms of any Secured Debt Agreement.

     17. CHIEF EXECUTIVE OFFICE; RECORDS. The chief executive office of each
Pledgor is located at the address specified in Annex F hereto for such Pledgor.
Each Pledgor will not move its chief executive office except to such new
location as such Pledgor may establish in accordance with the last sentence of
this Section 17. The originals of all documents in the possession of such
Pledgor evidencing all Collateral, including but not limited to all Limited
Liability Company Interests and Partnership Interests, and the only original
books of account and records of such Pledgor relating thereto are, and will
continue to be, kept at such chief executive office as specified in Annex F
hereto, or at such new locations as such Pledgor may establish in accordance
with the last sentence of this Section 17. All Limited Liability Company
Interests and Partnership Interests are, and will continue to be, maintained
at, and controlled and directed (including, without limitation, for general
accounting purposes) from, such chief executive office as specified in Annex F
hereto, or such new locations as such Pledgor may establish in accordance with
the last sentence of this Section 17. No Pledgor shall establish a new location
for such offices until (i) it shall have given to the Pledgee not less than 15
days' prior written notice of its intention so to do, clearly describing such
new location and providing such other information in connection therewith as
the Pledgee may reasonably request and (ii) with respect to such new location,
it shall have taken all action, satisfactory to the Pledgee, to maintain the
security interest of the Collateral Agent in the Collateral intended to be
granted hereby at all times fully perfected and in full force and effect.
Promptly after establishing a new location for such offices in accordance with
the immediately preceding sentence, the respective Pledgor shall deliver to the
Pledgee a supplement to Annex F hereto so as to cause such Annex F hereto to be
complete and accurate.

     18. PLEDGORS' OBLIGATIONS ABSOLUTE, ETC. The obligations of each Pledgor
under this Agreement shall be absolute and unconditional and shall remain in
full force and effect without regard to, and shall not be released, suspended,
discharged, terminated or 


                                     -17-
<PAGE>   18

otherwise affected by, any circumstance or occurrence whatsoever, including,
without limitation: (i) any renewal, extension, amendment or modification of or
addition or supplement to or deletion from any Secured Debt Agreement or any
other instrument or agreement referred to therein, or any assignment or
transfer of any thereof; (ii) any waiver, consent, extension, indulgence or
other action or inaction under or in respect of any such agreement or
instrument including, without limitation, this Agreement; (iii) any furnishing
of any additional security to the Pledgee or its assignee or any acceptance
thereof or any release of any security by the Pledgee or its assignee; (iv) any
limitation on any party's liability or obligations under any such instrument or
agreement or any invalidity or unenforceability, in whole or in part, of any
such instrument or agreement or any term thereof; or (v) any bankruptcy,
insolvency, reorganization, composition, adjustment, dissolution, liquidation
or other like proceeding relating to any Pledgor or any Subsidiary of any
Pledgor, or any action taken with respect to this Agreement by any trustee or
receiver, or by any court, in any such proceeding, whether or not such Pledgor
shall have notice or knowledge of any of the foregoing.

     19. ACTIONS REQUIRING FCC APPROVAL. (a) Notwithstanding anything to the
contrary contained in this Agreement, or any of the documents executed pursuant
hereto, the Pledgee will not take any action pursuant to this Agreement, or any
such documents, which would constitute or result in any assignment of any FCC
License or any transfer of control of the holder of any FCC License if such
assignment of such License or such transfer of control would require under then
existing law (including the Communications Act or the FCC Rules) the prior
approval of the FCC, without first obtaining such approval. In connection with
this Section 19 the Pledgee shall be entitled to rely upon the advice of FCC
counsel of the Pledgee's choice with respect to such assignment or transfer
(including to determine whether any such assignment or transfer has occurred or
will occur and whether or not prior approval of the FCC is required) whether or
not the advice rendered is ultimately determined to have been accurate.

     (b) If an Event of Default shall have occurred and be continuing, the
relevant Pledgor shall take any action which the Pledgee may request in the
exercise of its rights and remedies under this Agreement in order to transfer
or assign the Collateral to the Pledgee or to such one or more third parties as
the Pledgee may designate, or to a combination of the foregoing. To enforce the
provisions of this Section 19, after an Event of Default shall have occurred
and be continuing, the Pledgee is empowered to request, and each Pledgor agrees
to authorize, the appointment of a receiver or trustee from any court of
competent jurisdiction. Such receiver or trustee shall be instructed to seek
from the FCC (and any other governmental authority) such consent or approval as
may be required by the Communications Act and the FCC Rules for any assignment
of the assets of or transfer of control of any or all of the FCC Licenses or of
any Person whose stock, partnership interests or other equity interest is
subject to this Agreement to the extent required for such trustee or receiver
to assume such control for the purpose of seeking a bona fide purchaser to whom
such FCC Licenses will be assigned or control of such entity ultimately will be
transferred. Each Pledgor agrees, at such Pledgor's own cost and expense, to
cooperate with any such trustee or receiver, or at such trustee's or receiver's
direction, a bona-fide purchaser and with the Pledgee in the preparation,
execution and filing of any applications and other documents and providing any
information that may be necessary or helpful in obtaining the FCC's consent to
the assignment or transfer to such trustee or receiver, or at such trustee's or
receiver's direction, such purchaser of the Collateral or any of the FCC
Licenses. To the fullest


                                     -18-
<PAGE>   19

extent permitted by applicable law, each Pledgor hereby agrees to consent to
and authorize any such transfer of control upon the request of the Pledgee
after the occurrence and during the continuation of an Event of Default and,
without limiting any rights of the Pledgee under this Agreement, to authorize
the Pledgee to nominate a trustee or receiver to assume control of the
Collateral, subject only to any required consents, approvals or orders of
courts of competent jurisdiction, the FCC or other governmental authorities,
for the purpose of effectuating the transactions contemplated in this Section
19(b). Such trustee or receiver shall have all the rights and powers as
provided to it by law, court order or the Pledgee under this Agreement. Each
Pledgor shall cooperate fully and use its best efforts in obtaining the consent
of the FCC and the approval or consent of each other governmental authority
required to effectuate the foregoing.

     (c) Each Pledgor shall use its best efforts to assist in obtaining consent
or approval of the FCC, any court and any other governmental authority, if
required, for any action or transactions contemplated by this Agreement,
including, without limitation, the preparation, execution and filing with the
FCC of the transferor's or assignor's portion of any application or
applications for consent to the transfer of control or assignment necessary or
appropriate under the FCC's policies, rules and regulations for approval of the
transfer or assignment of all or any portion of the Collateral.

     (d) Each Pledgor hereby acknowledges and agrees that the FCC Licenses are
unique assets and that a violation of such Pledgor's covenant to cooperate with
respect to the obtainment of any regulatory consents would result in
irreparable harm to the Pledgee for which monetary damages are not readily
ascertainable. Each Pledgor further agrees that, because of the unique nature
of its undertakings in this Section 19, the same may be specifically enforced,
and such Pledgor hereby waives, and agrees to waive, any claim or defense that
the Pledgee would have an adequate remedy at law for the breach of such
undertakings and any requirement for the posting of bond or other certificate.

     (e) Without limiting the obligations of any Pledgor hereunder in any
respect, each Pledgor further agrees that if such Pledgor, upon or after the
occurrence and during the continuance of an Event of Default, should fail or
refuse to execute any application or other document necessary or appropriate to
obtain any governmental consent necessary or appropriate for the exercise of
any right of the Pledgee hereunder, such Pledgor agrees that, to the full
extent permitted by the Communications Act and the FCC Rules, such application
or other document may be executed on such Pledgor's behalf by the clerk of any
court or other forum in any competent jurisdiction without notice to such
Pledgor.

     (f) This Section 19 shall not limit any other rights or remedies of the
Pledgee or the Secured Creditors available under applicable law including,
without limitation, the Communications Act and the FCC Rules.

     20. REGISTRATION, ETC. (a) If there shall have occurred and be continuing
an Event of Default then, and in every such case, upon receipt by any Pledgor
from the Pledgee of a written request or requests that such Pledgor cause any
registration, qualification or compliance under any Federal or state securities
law or laws to be effected with respect to all or any part of the Collateral
consisting of Securities, Limited Liability Company Interests or 


                                     -19-
<PAGE>   20

Partnership Interests, such Pledgor as soon as practicable and at its expense
will use its reasonable best efforts to cause such registration to be effected
(and be kept effective) and will use its reasonable best efforts to cause such
qualification and compliance to be declared effected (and be kept effective) as
may be so requested and as would permit or facilitate the sale and distribution
of such Collateral, including, without limitation, registration under the
Securities Act, as then in effect (or any similar statute then in effect),
appropriate qualifications under applicable blue sky or other state securities
laws and appropriate compliance with any other government requirements,
provided that the Pledgee shall furnish to such Pledgor such information
regarding the Pledgee as such Pledgor may reasonably request in writing and as
shall be required in connection with any such registration, qualification or
compliance. Such Pledgor will cause the Pledgee to be kept advised in writing
as to the progress of each such registration, qualification or compliance and
as to the completion thereof, will furnish to the Pledgee such number of
prospectuses, offering circulars or other documents incident thereto as the
Pledgee from time to time may reasonably request, and will indemnify the
Pledgee, each other Secured Creditor and all others participating in the
distribution of such Collateral against all claims, losses, damages and
liabilities caused by any untrue statement (or alleged untrue statement) of a
material fact contained therein (or in any related registration statement or
other offering document) or by any omission (or alleged omission) to state
therein (or in any related registration statement or other offering document) a
material fact required to be stated therein or necessary to make the statements
therein not misleading, except insofar as the same may have been caused by an
untrue statement or omission based upon information furnished in writing to
such Pledgor by the Pledgee or such other Secured Creditor expressly for use
therein.

     (b) If at any time when the Pledgee shall determine to exercise its right
to sell all or any part of the Collateral consisting of Securities, Limited
Liability Company Interests or Partnership Interests pursuant to Section 7
hereof, and the Collateral or the part thereof to be sold shall not, for any
reason whatsoever, be effectively registered under the Securities Act, as then
in effect, the Pledgee may, in its sole and absolute discretion, sell such
Collateral, as the case may be, or part thereof by private sale in such manner
and under such circumstances as the Pledgee may deem necessary or advisable in
order that such sale may legally be effected without such registration. Without
limiting the generality of the foregoing, in any such event the Pledgee, in its
sole and absolute discretion (i) may proceed to make such private sale
notwithstanding that a registration statement for the purpose of registering
such Collateral or part thereof shall have been filed under such Securities
Act, (ii) may approach and negotiate with a single possible purchaser to effect
such sale, and (iii) may restrict such sale to a purchaser who will represent
and agree that such purchaser is purchasing for its own account, for
investment, and not with a view to the distribution or sale of such Collateral
or part thereof. In the event of any such sale, the Pledgee shall incur no
responsibility or liability for selling all or any part of the Collateral at a
price which the Pledgee, in its sole and absolute discretion, in good faith
deems reasonable under the circumstances, notwithstanding the possibility that
a substantially higher price might be realized if the sale were deferred until
after registration as aforesaid.

     21. TERMINATION; RELEASE. (a) After the Termination Date, this Agreement
and the security interest created hereby shall terminate (provided that all
indemnities set forth herein including, without limitation, in Section 11
hereof shall survive any such termination), and the Pledgee, at the request and
expense of any Pledgor, will execute and deliver to such


                                     -20-
<PAGE>   21

Pledgor a proper instrument or instruments acknowledging the satisfaction and
termination of this Agreement, and will duly assign, transfer and deliver to
such Pledgor (without recourse and without any representation or warranty) such
of the Collateral as has not theretofore been sold or otherwise applied or
released pursuant to this Agreement, together with any monies at the time held
by the Pledgee or any of its sub-agents hereunder. As used in this Agreement,
"Termination Date" shall mean the date upon which the Total Commitment and all
Interest Rate Protection Agreements and Other Hedging Agreements have been
terminated, no Note under the Credit Agreement is outstanding (and all Loans
have been repaid in full), all Letters of Credit have been terminated and all
Obligations then due and payable have been paid in full.

     (b) In the event that any part of the Collateral is sold in connection
with a sale permitted by Section 9.02 of the Credit Agreement (other than a
sale to any Pledgor or any Subsidiary of any Pledgor) or is otherwise released
at the direction of the Required Lenders (or all the Lenders if required by
Section 13.12 of the Credit Agreement) and the proceeds of such sale or sales
or from such release are applied in accordance with the provisions of the
Credit Agreement, to the extent required to be so applied, the Pledgee, at the
request and expense of any Pledgor, will duly assign, transfer and deliver to
such Pledgor (without recourse and without any representation or warranty) such
of the Collateral (and releases therefor) as is then being (or has been) so
sold or released and has not theretofore been released pursuant to this
Agreement.

     (c) At any time that a Pledgor desires that the Pledgee assign, transfer
and deliver Collateral (and releases therefor) as provided in Section 21(a) or
(b) hereof, it shall deliver to the Pledgee a certificate signed by an officer
of such Pledgor stating that the release of the respective Collateral is
permitted pursuant to such Section 21(a) or (b).

     (d) The Pledgee shall have no liability whatsoever to any other Secured
Creditor as the result of any release of Collateral by it in accordance with
this Section 21.

     22. NOTICES, ETC. All such notices and communications provided for
hereunder shall be in writing (including telegraphic, telex, telecopier or
cable communication) and mailed, telegraphed, telexed, telecopied, cabled or
delivered to the appropriate address set forth below. All such notices and
communications shall, when mailed, telegraphed, telexed, telecopied, or cabled
or sent by overnight courier, be effective when deposited in the mails,
delivered to the telegraph company, cable company or overnight courier, as the
case may be, or sent by telex or telecopier, except that notices and
communications to (x) the Pledgee shall not be effective until received by the
Pledgee and (y) any Pledgor shall not be effective until received by any such
Pledgor, as the case may be. All notices and other communications shall be in
writing and addressed as follows:

     (a) if to any Pledgor, at the address set forth opposite such Pledgor's
signature below;


                                     -21-
<PAGE>   22

     (b) if to the Pledgee, at:

     Bankers Trust Company
     One Bankers Trust Plaza
     130 Liberty Street
     New York, NY  10006
     Attention: Greg Shefrin
     Telephone No.: (212) 250-1724
     Telecopier No.: (212) 250-7218

     (c) if to any Lender Creditor, either (x) to the Administrative Agent, at
the address of the Administrative Agent specified in the Credit Agreement or
(y) at such address as such Lender Creditor shall have specified in the Credit
Agreement;

     (d) if to any Other Creditor at such address as such Other Creditor shall
have specified in writing to the Pledgors and the Pledgee;

or at such other address as shall have been furnished in writing by any Person
described above to the party required to give notice hereunder.

     23. WAIVER; AMENDMENT. None of the terms and conditions of this Agreement
may be changed, waived, modified or varied in any manner whatsoever unless in
writing duly signed by each Pledgor directly affected thereby and the Pledgee
(with the written consent of either (x) the Required Lenders (or all of the
Lenders to the extent required by Section 13.12 of the Credit Agreement) at all
times prior to the time when all Credit Document Obligations have been paid in
full or (y) the holders of at least a majority of the outstanding Other
Obligations at all times after the time when all Credit Document Obligations
have been paid in full); provided that any change, waiver, modification or
variance affecting the rights and benefits of a single Class (as defined below)
of Secured Creditors (and not all Secured Creditors in a like or similar
manner) shall also require the written consent of the Requisite Creditors (as
defined below) of such affected Class. For the purpose of this Agreement, the
term "Class" shall mean each class of Secured Creditors, i.e., whether (i) the
Lender Creditors as holders of the Credit Document Obligations or (ii) the
Other Creditors as the holders of the Other Obligations. For the purpose of
this Agreement, the term "Requisite Creditors" of any Class shall mean each of
(i) with respect to the Credit Document Obligations, the Required Lenders and
(ii) with respect to the Other Obligations, the holders of at least a majority
of all obligations outstanding from time to time under the Interest Rate
Protection Agreements and Other Hedging Agreements.

     24. MISCELLANEOUS. This Agreement shall be binding upon the parties hereto
and their respective successors and assigns and shall inure to the benefit of
and be enforceable by each of the parties hereto and its successors and
assigns, provided that no Pledgor may assign any of its rights or obligations
under this Agreement without the prior consent of the Collateral Agent. THIS
AGREEMENT SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH AND GOVERNED BY
THE INTERNAL LAWS OF THE STATE OF NEW YORK. EACH PLEDGOR IRREVOCABLY WAIVES ALL
RIGHT TO A TRIAL BY JURY IN ANY ACTION PROCEEDING OR COUNTERCLAIM ARISING


                                     -22-
<PAGE>   23

OUT OF OR RELATING TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.
The headings in this Agreement are for purposes of reference only and shall not
limit or define the meaning hereof. This Agreement may be executed in any
number of counterparts, each of which shall be an original, but all of which
shall constitute one instrument. In the event that any provision of this
Agreement shall prove to be invalid or unenforceable, such provision shall be
deemed to be severable from the other provisions of this Agreement which shall
remain binding on all parties hereto. EACH PLEDGOR HEREBY IRREVOCABLY CONSENTS
TO AND WAIVES ANY RIGHT TO OBJECT TO OR OTHERWISE CONTEST THE APPOINTMENT OF A
RECEIVER AFTER THE OCCURRENCE AND DURING THE CONTINUANCE OF AN EVENT OF
DEFAULT. EACH PLEDGOR HEREBY GRANTS SUCH CONSENT AND WAIVER KNOWINGLY AFTER
HAVING DISCUSSED THE IMPLICATIONS THEREOF WITH COUNSEL, ACKNOWLEDGES THAT THE
UNCONTESTED RIGHT TO HAVE A RECEIVER APPOINTED FOR THE FOREGOING PURPOSES IS
CONSIDERED ESSENTIAL BY THE PLEDGEE AND THE SECURED CREDITORS IN CONNECTION
WITH THE ENFORCEMENT OF THEIR RIGHTS AND REMEDIES HEREUNDER AND UNDER THE OTHER
CREDIT DOCUMENTS, AND THE AVAILABILITY OF SUCH APPOINTMENT AS A REMEDY UNDER
THE FOREGOING CIRCUMSTANCES WAS A MATERIAL FACTOR IN INDUCING THE LENDERS TO
MAKE (AND COMMIT TO MAKE) LOANS TO THE BORROWER AND IN INDUCING THE OTHER
CREDITORS TO ENTER INTO INTEREST RATE PROTECTION AGREEMENTS AND OTHER HEDGING
AGREEMENTS WITH THE BORROWER, AND AGREES TO ENTER INTO ANY AND ALL STIPULATIONS
IN ANY LEGAL ACTIONS, OR AGREEMENTS OR OTHER INSTRUMENTS IN CONNECTION WITH THE
FOREGOING AND TO COOPERATE FULLY WITH THE PLEDGEE AND THE REQUIRED LENDERS, OR,
THE HOLDERS OF A MAJORITY OF THE OTHER OBLIGATIONS, AS THE CASE MAY BE, IN
CONNECTION WITH THE ASSUMPTION AND EXERCISE OF CONTROL BY THE RECEIVER OVER ALL
OR ANY PORTION OF THE COLLATERAL.

     25. RECOURSE. This Agreement is made with full recourse to the Pledgors
and pursuant to and upon all the representations, warranties, covenants and
agreements on the part of the Pledgors contained herein and in the other
Secured Debt Agreements and otherwise in writing in connection herewith or
therewith.

     26. ADDITIONAL PLEDGORS. It is understood and agreed that any Subsidiary
of the Borrower that is required to execute a counterpart of this Agreement
after the date hereof pursuant to Section 8.13 or 9.15 of the Credit Agreement
shall automatically become a Pledgor hereunder by executing a counterpart
hereof and delivering the same to the Pledgee.

                                    * * * *


                                     -23-
<PAGE>   24

     IN WITNESS WHEREOF, each Pledgor and the Pledgee have caused this
Agreement to be executed by their duly elected officers duly authorized as of
the date first above written.


Address:

                                      PAGEMART WIRELESS, INC.,
3333 Lee Parkway, Suite 100             as a Pledgor
Dallas, TX  75219
Attention:  G. Clay Myers
Telephone:  (214) 765-3510
Telecopier:  (214) 765-4961          By
                                        ---------------------------------------
                                        Name:
                                        Title:


Accepted and Agreed to:

BANKERS TRUST COMPANY,
  as Collateral Agent and Pledgee


By  
  ------------------------------------
  Name:
  Title:


<PAGE>   25

                                                                   ANNEX A
                                                                      to
                                                               PLEDGE AGREEMENT


                              LIST OF SUBSIDIARIES

<PAGE>   26

                                                                   ANNEX B
                                                                      to
                                                               PLEDGE AGREEMENT


LIST OF STOCK

I.   PageMart Wireless, Inc.

<TABLE>
<CAPTION>
                                                                              Percentage of           Relevant Sub-
                                                                Number      Outstanding Shares          Clause of 
       Name of Issuing        Certificate        Type of          of                of                Section 3.2(a)
         Corporation             Number          Shares         Shares        Capital Stock        of Pledge Agreement
         -----------             ------          ------         ------        -------------        -------------------
       <S>                    <C>                <C>            <C>         <C>                    <C>


         ===========             ======          ======         ======        =============        ===================
</TABLE>



<PAGE>   27

                                                                   ANNEX C
                                                                      to
                                                               PLEDGE AGREEMENT


                                 LIST OF NOTES



I.   PageMart Wireless, Inc.

<TABLE>
<CAPTION>
Amount                            Maturity Date                 Obligor            Relevant Sub-clause of 
------                            -------------                 -------                 Section 3.2(a)
                                                                                     of Pledge Agreement
                                                                                     -------------------
<S>                               <C>                           <C>                <C>


</TABLE>


<PAGE>   28

                                                                   ANNEX D
                                                                      to
                                                               PLEDGE AGREEMENT


                  LIST OF LIMITED LIABILITY COMPANY INTERESTS




<PAGE>   29
                                                                   ANNEX E
                                                                      to
                                                               PLEDGE AGREEMENT


                         LIST OF PARTNERSHIP INTERESTS


<PAGE>   30

                                                                   ANNEX F
                                                                      to
                                                               PLEDGE AGREEMENT


                        LIST OF CHIEF EXECUTIVE OFFICES



I.   PageMart Wireless, Inc.


<PAGE>   31

                                                                   ANNEX G
                                                                      to
                                                               PLEDGE AGREEMENT

    Form of Agreement Regarding Uncertificated Securities, Limited Liability
                  Company Interests and Partnership Interests


     AGREEMENT (as amended, modified or supplemented from time to time, this
"Agreement"), dated as of _______ __, ____, among each of the undersigned
pledgors (each a "Pledgor" and, collectively, the "Pledgors"), Bankers Trust
Company, not in its individual capacity but solely as Collateral Agent, under,
and as defined in, the Pledge Agreement referred to below, (the "Pledgee"), and
__________, as the issuer of the Uncertificated Securities, Limited Liability
Company Interests and/or Partnership Interests (each as defined below) (the
"Issuer").

                             W I T N E S S E T H :

     WHEREAS, each Pledgor and the Pledgee have entered into a Pledge
Agreement, dated as of March 23, 1999 (as amended, amended and restated,
modified or supplemented from time to time, the "Pledge Agreement"), under
which, among other things, in order to secure the payment of the Obligations
(as defined in the Pledge Agreement), each Pledgor will pledge to the Pledgee
for the benefit of the Secured Creditors (as defined in the Pledge Agreement),
and grant a security interest in favor of the Pledgee for the benefit of the
Secured Creditors in, all of the right, title and interest of such Pledgor in
and to any and all (1) "uncertificated securities" (as defined in Section
8-102(a)(18) of the Uniform Commercial Code, as adopted in the State of New
York) ("Uncertificated Securities"), (2) Partnership Interests (as defined in
the Pledge Agreement) and (3) Limited Liability Company Interests (as defined
in the Pledge Agreement), in each case issued from time to time by the Issuer,
whether now existing or hereafter from time to time acquired by such Pledgor
(with all of such Uncertificated Securities, Partnership Interests and Limited
Liability Company Interests being herein collectively called the "Issuer
Pledged Interests"); and

     WHEREAS, each Pledgor desires the Issuer to enter into this Agreement in
order to perfect the security interest of the Pledgee under the Pledge
Agreement in the Issuer Pledged Interests, to vest in the Pledgee control of
the Issuer Pledge Interests and to provide for the rights of the parties under
this Agreement;

     NOW THEREFORE, in consideration of the premises and the mutual promises
and agreements contained herein, and for other valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
hereby agree as follows:

     1. Each Pledgor hereby irrevocably authorizes and directs the Issuer, and
the Issuer hereby agrees, to comply with any and all instructions and orders
originated by the Pledgee (and its successors and assigns) regarding any and
all of the Issuer Pledged Interests without the further consent by the
registered owner (including the respective Pledgor), and not to comply 

<PAGE>   32

with any instructions or orders regarding any or all of the Issuer Pledged
Interests originated by any person or entity other than the Pledgee (and its
successors and assigns) or a court of competent jurisdiction.

     2. The Issuer hereby certifies that (i) no notice of any security
interest, lien or other encumbrance or claim affecting the Issuer Pledged
Interests (other than the security interest of the Pledgee) has been received
by it, and (ii) the security interest of the Pledgee in the Issuer Pledged
Interests has been registered in the books and records of the Issuer.

     3. The Issuer hereby represents and warrants that (i) the pledge by the
Pledgors of, and the granting by the Pledgors of a security interest in, the
Issuer Pledged Interests to the Pledgee, for the benefit of the Secured
Creditors, does not violate the charter, by-laws, partnership agreement,
membership agreement or any other agreement governing the Issuer or the Issuer
Pledged Interests, and (ii) the Issuer Pledged Interests are fully paid and
nonassessable.

     4. All notices, statements of accounts, reports, prospectuses, financial
statements and other communications to be sent to any Pledgor by the Issuer in
respect of the Issuer will also be sent to the Pledgee at the following
address:

                           Bankers Trust Company
                           One Bankers Trust Plaza
                           130 Liberty Street
                           New York, NY  10006
                           Attention: Greg Shefrin
                           Tel: (212) 250-1724
                           Fax: (212) 250-7218

     5. Until the Pledgee shall have delivered written notice to the Issuer
that all of the Obligations have been paid in full and this Agreement is
terminated, the Issuer will send any and all redemptions, distributions,
interest or other payments in respect of the Issuer Pledged Interests from the
Issuer for the account of the Pledgor only by wire transfers to the following
address:

                           ___________________
                           ___________________
                           ___________________
                           ___________________
                           ABA No.: ___________________________
                           Account in the Name of:  ___________
                           Account No.:  ______________________

     6. Except as expressly provided otherwise in Sections 4 and 5 above, all
notices, instructions, orders and communications hereunder shall be sent or
delivered by mail, telex, telecopy or overnight courier service and all such
notices and communications shall, when mailed, telexed, telecopied or sent by
overnight courier, be effective when deposited in the mails or delivered to the
overnight courier, prepaid and properly addressed for delivery on such or the
next Business Day, or sent by telex or telecopier, except that notices and
communications to the Pledgee shall not be effective until received by the
Pledgee. All notices and other communications shall be in writing and addressed
as follows:


                                       2



                                     -25-
<PAGE>   33

                  (a)      if to any Pledgor, at:

                           PageMart Wireless, Inc.
                           3333 Lee Parkway, Suite 100
                           Dallas, TX 75219
                           Attention: G. Clay Myers
                           Tel.: (214) 765-3510
                           Fax: (214) 765-4961

                  (b)      if to the Pledgee, at:

                           Bankers Trust Company
                           One Bankers Trust Plaza
                           130 Liberty Street
                           New York, NY  10006
                           Attention: Greg Shefrin
                           Tel: (212) 250-1724
                           Fax: (212) 250-7218

                  (c)      if to the Issuer, at:

                           ___________________
                           ___________________
                           ___________________
                           Attention:  ___________________
                           Telephone No.:_________________
                           Telecopier No.:________________

or at such other address as shall have been furnished in writing by any person
described above to the party required to give notice hereunder. As used in this
Section 6, "Business Day" means any day other than a Saturday, Sunday, or other
day in which banks in New York are authorized to remain closed.

     7. This Agreement shall be binding upon the successors and assigns of each
Pledgor and the Issuer and shall inure to the benefit of and be enforceable by
the Pledgee and its successors and assigns. This Agreement may be executed in
any number of counterparts, each of which shall be an original, but all of
which shall constitute one instrument. In the event that any provision of this
Agreement shall prove to be invalid or unenforceable, such provision shall be
deemed to be severable from the other provisions of this Agreement which shall
remain binding on all parties hereto. None of the terms and conditions of this
Agreement may be changed, waived, modified or varied in any manner whatsoever
except in writing signed by the Pledgee, the Issuer and any Pledgor which at
such time owns any Issuer Pledged Interests.


                                       3
<PAGE>   34

     8. This Agreement shall be governed by and construed in accordance with
the law of the State of New York, without regard to its principles of conflict
of laws.

     IN WITNESS WHEREOF, each Pledgor, the Pledgee and the Issuer have caused
this Agreement to be executed by their duly elected officers duly authorized as
of the date first above written.


                                     [____________________________],(1)
                                        as a Pledgor


                                     By
                                       ---------------------------------------
                                       Name:
                                       Title:


                                     BANKERS TRUST COMPANY,
                                       not in its individual capacity but 
                                       solely as Collateral Agent and Pledgee


                                     By
                                       ---------------------------------------
                                       Name:
                                       Title:


                                     [____________________________],
                                        the Issuer


                                     By
                                       ---------------------------------------
                                       Name:
                                       Title:




---------------

(1)  Insert signature block for each Pledgor party to this Agreement.


                                       4