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                                                                      EXHIBIT 10
                               PURCHASE AGREEMENT


         THIS PURCHASE AGREEMENT (this "Agreement") is made and entered into
this ___ day of _______, 1999, by and among AESCO SYSTEMS, INC. a Pennsylvania
corporation ("Seller"), AMERICAN TELECASTING OF PORTLAND, INC., a Delaware
corporation ("Buyer"), and AMERICAN TELECASTING, INC., a Delaware corporation
("ATI").

         WHEREAS, Seller holds the authorization issued by the Federal
Communications Commission ("FCC") for Multichannel Multipoint Distribution
Service ("MMDS") Station WHT647, the four E-Group channels, in Portland, Oregon
(the "Station");

         WHEREAS, Buyer desires to purchase from Seller and Seller desires to
sell to Buyer all rights of Seller to operate the Station under its FCC
authorization; and

         NOW, THEREFORE, in consideration of the premises and promises herein
contained, the parties agree as set forth below.

         Section 1.        Purchase and Sale of Assets.

                  (a) Assets. At the Closing (as defined in Section 3(a)
         below), Seller shall sell, transfer, assign and deliver to Buyer, and
         Buyer shall purchase, accept, assume and receive, all right, title and
         interest in, to or arising from the Assets. The "Assets" are (a) all
         of Seller's ownership rights in the Station, including all of Seller's
         rights as the holder of the FCC authorization for the Station (the
         "Authorization"), and (b) all transferable documents and records owned
         by, held by, or under the control of the Seller, if any, used in the
         operation of the Station. The "Assets" do not include, and Seller has
         no obligation to transfer, assign, sell or deliver to Buyer, any
         rights or claims under this Agreement or against any third party,
         whether arising under a contract, in tort or otherwise, including
         rights to receivables (e.g., accounts receivable from ATI, tax
         refunds, etc.).

                  (b) Liabilities. Neither party shall assume or be liable or
         responsible for any debt, obligation or liability of the other party,
         or any affiliate, successor, heir or assign of the other party, or any
         claim against any of the foregoing, of any kind, whether known or
         unknown, contingent, absolute, or otherwise.

         Section 2. Purchase Price. The purchase price for the Assets shall be
(i) the amount determined pursuant to Section 2(a) (the "Fixed Payment") plus
(ii) the Deferred Payment, as defined below.

                  (a) Fixed Payment. The Fixed Payment shall be paid by Buyer
         to Seller via wire transfer of immediately available funds to Seller
         in accordance with instructions provided by Seller at least 2 business
         days before Closing upon the latter to occur of (A) the closing of
         sales after December 31, 1998 of wireless spectrum or wireless
         markets, other than a sale to BellSouth or any of its affiliates, in
         which ATI and its affiliates realize $5,000,000 or more in the
         aggregate, and (B) FCC approval by Final Order (as defined in 




<PAGE>   2

         Section 8(a) below) of the Assignment Application (as defined in
         Section 7 below); provided, however, that Buyer may in its sole
         discretion waive in writing either or both of the conditions set forth
         above and may choose to close notwithstanding their non-satisfaction.
         The date upon which the conditions set forth in the prior sentence
         have been satisfied or waived is referred to as the "Closing Trigger
         Date." The amount of the Fixed Payment shall be $2,250,000; provided,
         however, if such amount has not been paid in full prior to July 1,
         1999, then the amount due as the Fixed Payment shall thereafter be
         increased at a rate of $22,500 per month until the date of payment.

                  (b)      Deferred Payment.

                           (i) Seller shall be entitled to receive the Deferred
                  Payment from Buyer in respect of any transaction which closes
                  within five years after the date of this Agreement (the
                  "Deferred Transaction") in which Buyer or its shareholders or
                  affiliates, but not any unrelated assignee or successor,
                  transfers rights in the Station (directly or indirectly,
                  including through any transfer of interests in the Buyer or
                  it affiliates (other than American Telecasting, Inc. or
                  stockholders of American Telecasting, Inc.), whether by
                  merger, consolidation, share exchange, issuance or sale of
                  securities, purchase or redemption of securities,
                  recapitalization, reorganization, division, liquidation or
                  any other individual or series of transactions of similar
                  substantive effect), either by itself or in conjunction with
                  other wireless stations owned or leased by Buyer, including
                  any transaction which requires FCC approval pursuant to
                  Section 310(d) of the Communications Act. Buyer shall notify
                  Seller of any Deferred Transaction, and shall provide Seller
                  with the necessary information regarding such transaction to
                  calculate the Deferred Payment. The Deferred Payment shall be
                  equal to (x) one-third of the purchase price (whether in cash
                  or in-kind) received by Buyer or its shareholders or
                  affiliates for all Portland, Oregon wireless stations sold or
                  assigned in the Deferred Transaction multiplied by a
                  fraction, the numerator of which is 4 and the denominator of
                  which is (1) the total number of Portland, Oregon MMDS and
                  Multichannel Distribution Service ("MDS") wireless channels
                  assigned, or the leases for which are assigned, in the
                  Deferred Transaction, plus (2) one-half of the number of
                  Portland, Oregon Instructional Television Fixed Service
                  ("ITFS") wireless channels assigned, or the leases for which
                  are assigned, in the Deferred Transaction, minus (y)
                  $2,500,000. In the event the Deferred Payment as calculated
                  above is equal to or less than zero, no payment shall be
                  made. The Deferred Payment, or any portion thereof, shall be
                  paid only with respect to cash or other in-kind proceeds
                  actually received by Buyer, subject to Section 2(b)(iii)(a),
                  and shall be paid by Buyer to Seller within 15 days after
                  such receipt.

                           (ii) If assets outside of the Portland, Oregon
                  wireless stations are also transferred in the Deferred
                  Transaction, the portion of the purchase price to be
                  allocated to the Portland, Oregon wireless stations for
                  purposes of the calculation in Section 2(b)(i) will be
                  determined based upon the relative fair market values of the
                  assets transferred (and in comparing the value of wireless
                  stations, 



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                  consideration of the relative number of households within the
                  protected service areas of the respective markets and the
                  number of channels transferred in the respective markets). If
                  the parties do not agree upon an appropriate allocation, an
                  independent appraiser shall be selected by the parties within
                  ten days after written notification by either party to the
                  other of the dispute. The appraiser shall make a final
                  binding allocation within 60 days of appointment. The cost of
                  the appraisal will be shared equally by Buyer and Seller. For
                  purposes of Sections 2(b)(i) and 2(b)(ii), non-cash
                  consideration will be valued at the fair market value of such
                  consideration.

                           (iii) For purposes of calculating the purchase price
                  received in a Deferred Transaction:

                  (a) To the extent the purchase price received in a Deferred
         Transaction is in the form of a note (or other obligation to make
         payment) issued within five years after the date of this Agreement by
         a party to the Deferred Transaction or an affiliate thereof, the
         receipt of such note shall not be treated as the receipt of purchase
         price, but all payments received in respect of such note (whether
         characterized as principal, interest or otherwise) shall be treated as
         receipt of purchase price, even if received more than five years after
         the date of this Agreement.

                  (b) If in connection with a Deferred Transaction the buyer or
         any of its shareholders or affiliates receives consideration for any
         rights or services in excess of the fair market value thereof or
         receives a dividend or distribution in excess of its or his
         proportionate share of the stock or interests on which such dividend
         or distribution is made, such excess shall be treated as purchase
         price for the wireless stations that are the subject of the Deferred
         Transaction.

                           (iv) As hypothetical examples, the following
                  represents the method for calculating the Deferred Payment if
                  Buyer were to sell, or assign the leases for, 13 MMDS and MDS
                  wireless cable channels and 20 ITFS wireless cable channels
                  in the Portland, Oregon market for a total price of (A) $43.1
                  million or (B) $53.1 million:

<TABLE>
<S>                                        <C>            
         Hypothetical Deferred Payment A = (1/3) x ($43.1 million x (4/23)) - $2,500,000 
                                         = (1/3) x ($43.1 million x 0.1739) - $2,500,000
                                         = $2,498,551 - $2,500,000
                      Deferred Payment A = $0


         Hypothetical Deferred Payment B = (1/3) x ($53.1 million x (4/23)) - $2,500,000 
                                         = (1/3) x ($53.1 million x 0.1739) - $2,500,000
                                         = $3,078,261 - $2,500,000
                      Deferred Payment B = $578,261
</TABLE>





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                           (v) If the Buyer fails to pay the Deferred Payment
                  within 15 days after the Deferred Transaction closing, the
                  Buyer shall pay compound interest at the rate of 1 1/2 % per
                  month (or, if less, the maximum rate permitted by law) on the
                  outstanding balance due until the payment is completed in
                  full. All payments will be paid in cash by Buyer to Seller by
                  wire transfer of immediately available funds to Seller in
                  accordance with Seller's instructions.

         Section 3.        The Closing and the Transfer of Assets.

                  (a) The Closing. Subject to the delivery of the documents set
         forth in Sections 3(c) and (d) below and the satisfaction of the
         conditions precedent set forth in Section 8 below, the transfer of
         Assets contemplated by this Agreement (the "Closing") shall occur at
         10:00 a.m. on the date determined by the mutual consent of the parties
         hereto, which date shall be within three business days after the
         Closing Trigger Date (the "Closing Date"), at the offices of
         McDermott, Will & Emery, 600 13th Street, N.W., Washington, D.C. or at
         such other location as mutually agreed upon by Buyer and Seller.

                  (b) Deliveries by Buyer. At the Closing, Buyer shall deliver
         to Seller against receipt of the deliveries from Seller required by
         Section 3(c), or shall cause to be delivered to Seller:

                           (i) the portion of the Fixed Payment, if any, then
                  owed by Buyer to Seller;

                           (ii) a certificate, dated the Closing Date, executed
                  by an executive officer of Buyer stating that all of Buyer's
                  representations and warranties made in this Agreement are
                  true and correct in all material respects on the Closing
                  Date, as if made on such date, and that Buyer has complied in
                  all material respects with all its covenants and agreements
                  set forth in this Agreement;

                           (iii) such other instruments or documents as may be
                 reasonably necessary to carry out the transactions
                 contemplated hereby.

                  (c) Deliveries by Seller. At the Closing, Seller shall
         deliver to Buyer against receipt of the deliveries from Buyer required
         by Section 3(b):

                           (i) a General Assignment and Bill of Sale, in
                  substantially the form of Schedule 3(c)(i) attached hereto;

                           (ii) a certificate, dated the Closing Date, executed
                  by an executive officer of Seller stating that all of
                  Seller's representations and warranties made in this
                  Agreement are true and correct in all material respects on
                  the Closing Date, as if made on such date, and that Seller
                  has complied in all material respects with all its covenants
                  and agreements set forth in this Agreement;




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                           (iii) such other instruments or documents as may be
                  reasonably necessary to carry out the transactions
                  contemplated hereby; and

                           (iv) a letter addressed to the FCC stating that the
                  FCC assignment has been consummated.

                  (d) Termination of Communications Services Agreement. Upon
         consummation of the Closing, the existing Communications Services
         Agreement between ATI and Seller dated July 30, 1993 (the
         "Communications Services Agreement") shall terminate, and Seller, on
         the one hand, and Buyer and ATI, on the other hand, effective as of
         the Closing, irrevocably and unconditionally release and forever
         discharge the other(s) and its/their affiliates and subsidiaries, and
         the officers, directors, employees, representatives, agents, servants,
         successors and assigns thereof, from any and all claims, liabilities,
         promises, controversies, damages, actions, causes of action, suits,
         demands, obligations and the like, whether known or unknown, arising
         out of or related to obligations under the Communications Services
         Agreement.

         Section 4. Expiration. Notwithstanding any breach hereof by either one
or both parties, this Agreement and the parties' respective obligations to
consummate the Closing shall expire, without the necessity of any action by
either party, on March 15, 2000. Such expiration of this Agreement shall be
without prejudice to any right to seek or obtain any legal or equitable remedy
(including specific performance hereof) which may have arisen from a
misrepresentation or breach committed prior to the termination, subject to
Section 8(c).

         Section 5. Representations and Warranties of Seller. Seller represents
and warrants to Buyer as of the date hereof, and as of the Closing, as set
forth below.

                  (a) Authority. Seller has full legal right, and corporate
         power and authority, without the consent of any other person, to
         execute and deliver this Agreement and, other than the requirement for
         FCC approval of assignment of the Authorization, to carry out the
         transactions contemplated hereby. All corporate acts or proceedings
         required to be taken by Seller to authorize the execution, delivery
         and performance of this Agreement and all transactions contemplated
         hereby have been duly and properly taken, other than the requirement
         for FCC approval of assignment of the Authorization which is required
         to be obtained prior to the Closing.

                  (b) Validity. This Agreement has been, and the documents to
         be delivered at the Closing will be, duly executed and delivered and
         constitute lawful, valid and legally binding obligations of Seller,
         enforceable in accordance with their respective terms. The execution
         and delivery of this Agreement and the consummation of the
         transactions contemplated hereby will not result in the creation of
         any lien, charge or encumbrance of any kind against any of the Assets
         or the acceleration of any indebtedness or other obligation of Seller
         and are not prohibited by, do not violate or conflict with any
         provision of, and do not constitute a default under or a breach of (a)
         the articles of incorporation or bylaws of Seller, (b) any contract,
         agreement or other instrument to which Seller is a party or by which
         Seller or any of the Assets are bound, (c) any order, 




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         writ, injunction, decree or judgment of any court or governmental
         agency, or (d) any law, rule or regulation applicable to Seller.
         Except for the prior approval of the FCC, no approval, authorization,
         consent or other order or action of or filing with any court,
         administrative agency or other governmental authority is required for
         the execution and delivery by Seller of this Agreement or such other
         agreements and instruments or the consummation by Seller of the
         transactions contemplated hereby or thereby.

                  (c) Due Organization. Seller is a corporation, validly
         existing and in good standing under the laws of the Commonwealth of
         Pennsylvania and has full power and authority and all requisite
         licenses, permits and franchises to own, lease and operate the
         Station. Seller is duly licensed and qualified to do business and is
         in good standing in all jurisdictions where failure to be so licensed
         or qualified would adversely affect the ability of Buyer to enforce
         any material rights included in the Assets.

                  (d) Title to Assets. Seller is the sole and exclusive legal
         and equitable owner of all right, title and interest in and has good
         and marketable title to all of the Assets, subject to any requirements
         for FCC approval of assignment of the Authorization. None of the
         Assets which Seller purports to own or hold are subject to (i) any
         contract, lease (other than the existing lease with Buyer), license or
         sale, (ii) any security interest, mortgage, pledge, lien, or charge of
         any kind or character, direct or indirect, whether accrued, absolute,
         contingent or otherwise, (iii) any royalty or commission arrangements,
         or (iv) any adverse claims, covenants or restrictions (other than
         those proposed by applicable law or FCC requirements).

                  (e) Litigation. As of the date hereof, there are no legal or
         administrative proceedings of any kind pending or, to the knowledge of
         Seller, threatened in any manner involving Seller which might have a
         material adverse effect on the Assets or Seller. If between the date
         hereof and the Closing Date Seller acquires knowledge of any
         litigation, proceeding or investigation that is pending or threatened
         and, if existing and known by Seller on the date hereof would make the
         representation stated in the preceding sentence false, Seller shall
         disclose to Buyer the existence of such proceeding and such additional
         information as Buyer may reasonably request to determine whether the
         condition set forth in Section 8(a)(c) hereof has been satisfied.
         Seller is not in default with respect to any judgment, order, decree,
         or similar instrument applicable to it which might have a material
         adverse effect on the Assets or Seller.

                  (f) Compliance with Law. The Assets conform in all material
         respects to all applicable laws, ordinances, codes, licensing
         requirements, rules and regulations, and Seller has not received any
         notice to the contrary. Seller has complied in all material respects
         with all laws, ordinances, regulations, licensing requirements, rules,
         decrees, awards or orders, and there is not and will not be any
         liability arising from or relating to any violations thereof.

                  (g) Authorization. Schedule 5(g) contains an accurate and
         complete copy of the Authorization. The Authorization is in full force
         and effect, and bears the full license term granted for MMDS licenses,
         expiring on May 1, 2001. Except as disclosed in 




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         Schedule 5(g) hereto, the Authorization is unimpaired by any act or
         omission of the Seller. The facilities authorized by the Authorization
         have been timely constructed in accordance with the construction
         authorization granted therefor and a certification of completion of
         construction was timely filed with the FCC. The issuance and
         assignment of the Authorization to the Seller has been approved by the
         FCC, by actions which can no longer be appealed by petitioners or set
         aside by the FCC by its own action. Except as disclosed in Schedule
         5(g) hereto, the Station has, since the initial certification of
         completion of construction was filed with the FCC, provided service as
         authorized in compliance with the FCC's Rules, including Section
         21.303(d) thereof. Seller has not agreed to accept any interference
         from any third party or to take any action to protect any third
         party's reception from interference. With regard to the Authorization,
         there is no complaint, inquiry, investigation or proceeding pending
         before the FCC or, to Seller's knowledge, threatened, other than
         proceedings of general applicability and not directed specifically at
         the Authorization, which, if determined as requested by the moving
         party or as indicated in any document initiating any inquiry,
         investigation or proceeding, could result in the revocation,
         modification, restriction, cancellation, termination or non-renewal of
         the Authorization, the dismissal or denial of an application, or other
         action which is adverse to Seller or the imposition of a monetary
         forfeiture. The Authorization is freely assignable to Buyer, subject
         to FCC consent. The FCC has not concluded in writing, nor to Seller's
         knowledge has it been alleged in writing, that Seller has violated any
         FCC rules or policies with regard to the Station.

         Section 6. Representations and Warranties of Buyer. Buyer and ATI
hereby represent and warrant to Seller as of the date hereof, and as of the
Closing, as follows:

                  (a) Authority. Buyer has full legal right, power and
         authority, without the consent of any other person, to execute and
         deliver this Agreement and to carry out the transactions contemplated
         hereby. All corporate and other acts or proceedings required to be
         taken by Buyer to authorize the execution, delivery and performance of
         this Agreement and all transactions contemplated hereby have been duly
         and properly taken.

                  (b) Validity. This Agreement has been, and the documents to
         be delivered at the Closing will be, duly executed and delivered and
         constitute lawful, valid and legally binding obligations of Buyer,
         enforceable in accordance with their respective terms. The execution
         and delivery of this Agreement and the consummation of the
         transactions contemplated hereby are not prohibited by, do not violate
         or conflict with any provision of, and do not constitute a default
         under or a breach of (a) the certificate of incorporation or bylaws of
         Buyer, (b) any contract, agreement or other instrument to which Buyer
         is a party or by which Buyer is bound, (c) any order, writ,
         injunction, decree or judgment of any court or governmental agency, or
         (d) any law, rule or regulation applicable to Buyer. Except for the
         prior approval of the FCC, no approval, authorization, consent or
         other order or action of or filing with any court, administrative
         agency or other governmental authority is required for the execution
         and delivery by Buyer of this Agreement or such other agreements and
         instruments or the consummation by Buyer of the transactions
         contemplated hereby or thereby.



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                  (c) Due Organization. Buyer is a Delaware corporation duly
         organized, validly existing and in good standing under the laws of the
         jurisdiction of its organization.

                  (d) Litigation. There are no legal or administrative
         proceedings of any kind now pending, or, to the knowledge of Buyer,
         threatened in any manner involving Buyer which might have a material
         adverse effect on Buyer's ability to consummate the transactions
         contemplated herein. Buyer is not in default with respect to any
         judgment, order, decree, or similar instrument applicable to it which
         might have a material adverse effect on Buyer' ability to consummate
         the transactions contemplated herein.

                  (e) Qualification to Hold Authorization. Buyer is qualified
         under the rules of the FCC to hold the Authorization without the need
         for waiver of any FCC rule.

         Section 7. Covenants. The parties indicated below hereby agree to
keep, perform and fully discharge the following covenants and agreements which
are applicable to them.

                  (a) No Shop. From the date hereof until the Closing or the
         termination or expiration of this Agreement (as applicable), Seller
         shall not take any action to seek, encourage, solicit or support any
         inquiry, proposal, expression of interest or offer from any other
         person or entity with respect to an acquisition, combination or
         similar transaction involving the Assets. In consideration for
         Seller's covenant pursuant to this Section 7(a), Buyer shall pay
         $250,000 to Seller via wire transfer of immediately available funds
         upon the execution and delivery of this Agreement by both parties
         hereto.

                  (b) Interim Conduct. From the date hereof until the Closing
         Date, Seller shall use all reasonable efforts to preserve, protect and
         maintain its rights and interests in and to the Assets, it being
         acknowledged by the parties that Seller's ability to do so with
         respect to the Authorization and those Assets which are leased to
         Buyer is subject to some extent to Buyer's compliance with the
         provisions of the channel lease agreement. Without limiting the
         generality of the foregoing, as pertains to or in any way affects the
         Assets, from the date hereof until the Closing Date, except for
         transactions expressly approved in writing by Buyer, Seller shall:

                           (i) not enter into, amend or terminate, or agree to
                  enter into, amend or terminate, any contract included within
                  or related to the Assets, except in the ordinary course of
                  business or in accordance with Section 7(c);

                           (ii) not sell, lease or otherwise dispose of or
                  agree to sell, lease or otherwise dispose of, any of the
                  Assets, or the rights or claims related thereto;

                           (ii) not incur or become subject to, nor agree to
                  incur or become subject to, any debt, obligation or
                  liability, contingent or otherwise that encumbers the Assets,
                  except current liabilities and contractual obligations in the
                  ordinary course of business; and




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                           (iii) not to modify the Station Authorization in any
                  way except as agreed between Seller and Buyer.

                  (c) Communications Services Agreement. The parties
         specifically acknowledge that (i) Seller has asserted a claim that the
         amount of the monthly payment (payable to Seller pursuant to paragraph
         C.4 of the Communications Services Agreement) should have increased
         and other payments should have been made pursuant to paragraph F.1 as
         a result of other agreements entered into by ATI prior to the date
         hereof (such claim, the "Seller's Claim") and (ii) ATI and Buyer have
         disputed the Seller's Claim. From the date hereof until the expiration
         or termination of this Agreement (as applicable), Seller agrees not,
         based on the Seller's Claim, to terminate the Communications Services
         Agreement, cease to perform any of its obligations thereunder or
         initiate any suit or action thereunder, provided that ATI and Buyer
         completely and timely (A) make all monthly payments required by the
         Communications Services Agreement, but without giving effect to any
         increase claimed pursuant to the Seller's Claim, (B) perform all other
         obligations of the "Customer" under the Communications Services
         Agreement and (C) perform all of their respective obligations under
         this Agreement. Seller, Buyer and ATI further agree that, should the
         Seller file a suit or action asserting the Seller's Claim after the
         expiration or termination of this Agreement, ATI hereby waives any
         defense based on the statute of limitations or laches as to the
         Seller's Claim with respect to the period between the date hereof and
         the date of expiration or termination, as appropriate.

                  (d) Access to Information Pertaining to the Assets. From the
         date hereof through the Closing Date, Seller shall give Buyer and its
         representatives full and free access to all properties, facilities,
         personnel, books, contracts, leases, commitments and records relating
         to the Assets, to the extent reasonably requested by Buyer in
         connection with its due diligence, preparation for the consummation of
         the transactions contemplated hereby or the operation of Station after
         the Closing; provided, however, Buyer shall exercise its rights only
         during normal business hours, after reasonable advance notice and in a
         manner that minimizes disruption to Seller's business. All information
         acquired by Buyer pursuant to this Section 7(c) shall be considered
         the confidential information of Seller. Notwithstanding anything in
         this Agreement to the contrary, nothing herein shall require Seller to
         provide Buyer with access to information to the extent that so doing
         would either (1) constitute violation of applicable law (e.g., as in
         the case of disclosure of the contents of employee files required to
         be kept confidential under the Americans With Disability Act) or (2)
         cause a forfeiture of Seller's privilege to protect communications
         (oral or written) between Seller's counsel, on the one hand, and
         Seller's directors, officers and/or employees, on the other hand
         (including communications relating to any claims Seller may have
         against ATI or Buyer).

                  (e) FCC Filings.

                           (i) Within five days after the date hereof, Seller
                  and Buyer shall join in an application to the FCC, to be
                  filed on FCC form 702 (the "Assignment Application"),
                  requesting the FCC's written consent to the assignment of the






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                  Authorization from Seller to Buyer. Each party shall pay its
                  own costs in preparing the Assignment Application. Buyer
                  shall pay any FCC filing fees associated with the Assignment
                  Application. Each of Seller and Buyer shall, at its own
                  expense, cooperate in providing all information and taking
                  all steps necessary, desirable or appropriate to expedite the
                  preparation, filing, prosecution and granting of such
                  application. In the event any person requests the FCC to deny
                  the Assignment Application, or otherwise challenges the grant
                  of the Assignment Application, or in the event the FCC
                  consents to the assignment of the Authorization to Buyer and
                  any person appeals or otherwise challenges such consent
                  before the FCC, each of Seller and Buyer shall, at its own
                  expense, oppose such petition or challenge, or defend such
                  action and the order of the FCC, diligently and in good faith
                  to the end that the transactions contemplated by this
                  Agreement may be finally consummated.

                           (ii) Seller shall cooperate with Buyer and shall
                  promptly. and in any event within five business days, after
                  requested by Buyer execute and file with the FCC all
                  documents reasonably requested by Buyer in connection with
                  filing and prosecuting any other applications with the FCC
                  for digital emissions, it being agreed that there shall be no
                  digital emissions or other modification to the Station
                  implemented prior to Closing.

                           (iii) During the two year period following the
                  Closing, Seller agrees that it will not file any petitions,
                  objections, competing proposals, applications or other
                  documents that would have as their purpose, intent, effect or
                  result the denial, dismissal, rejection or delay in the
                  granting of the applications or other requests to the FCC
                  filed on behalf of the Station.

                  (f) Best Efforts. Each party shall act in good faith and use
         its best efforts to consummate the transactions contemplated by this
         Agreement and shall not take any other action inconsistent with its
         obligations hereunder or which could hinder or delay the consummation
         of the transactions contemplated hereby.

                  (g) Information Regarding Subsequent Sales. Buyer shall
         notify Seller in writing of any sales of the types specified in
         Section 2(b) and in such notice shall inform Seller of the proceeds
         and the net proceeds of any such sale. Seller acknowledges that such
         information may not be publicly available and, unless and until it has
         been publicly disclosed by ATI. Buyer agrees to treat the information
         as confidential, not disclose it to any other party, and not use it in
         any way, except for purposes of determining eligibility to receive the
         payment set forth in Section 2(b). Seller further agrees to comply
         with all applicable securities laws with respect to use of such
         information, and agrees not to trade in ATI securities, or securities
         of any successor or assign of ATI, while in possession of such
         information or to provide such information to other persons for such
         purposes.



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                  (h)      Confidentiality.

                  (i) After the date hereof, except as may be required for tax
         purposes or other regulatory purposes, no party nor any affiliate of a
         party nor any of their respective successors and assigns shall use,
         publish or disclose, or permit others to use or disclose any
         information regarding this Agreement or regarding another party or its
         affiliates obtained in the negotiation and performance of this
         Agreement. In the event of any termination of this Agreement, (a) each
         party and its affiliates shall treat as confidential and proprietary
         and shall not disclose or use, directly or indirectly, in any manner
         whatsoever, or permit others under their control to disclose or to
         use, any information concerning this Agreement or concerning another
         party or its affiliates or their business or products obtained
         pursuant to or in connection with the transactions which are the
         subject matter of this Agreement, unless such information (i) was
         known when received, (ii) is or thereafter becomes lawfully obtainable
         from other sources, (iii) is necessary or appropriate to disclose to
         any regulatory authority having jurisdiction or as otherwise required
         by law, or (iv) is or becomes a matter of public knowledge without
         violation of this Section 7(h), and (b) each party shall promptly
         return to the other parties upon written request all written
         information and documents received from them and their affiliates, and
         their accountants or counsel, in connection with such transactions,
         including all copies thereof. The provisions of this Section 7(h)(i)
         shall survive the Closing and any expiration or termination of this
         Agreement.

                  (ii) In addition, after the date hereof Seller and its
         affiliates shall not use, publish, disclose, or permit others to use,
         publish or disclose any information regarding the Communications
         Services Agreement, the Seller's Claim, or prices paid by Buyer and
         its affiliates to channel lessors, except as may be required in
         connection with any suit or action the Seller may initiate, in
         accordance with the terms hereof, alleging breach of the
         Communications Services Agreement. The provisions of this Section
         7(h)(ii) shall survive the Closing for a period of two years, but
         shall not survive any expiration or termination of this Agreement.

         Section 8. Conditions Precedent.

                  (a) Conditions Precedent to Obligations of Buyer. Each and
         all of the obligations of Buyer to consummate the transactions
         contemplated by this Agreement are subject to fulfillment prior to or
         at the Closing of the following conditions: (a) the representations
         and warranties of Seller contained herein shall be accurate in all
         material respects as if made on and as of the Closing Date; (b) Seller
         shall in all material respects have performed all of the obligations
         and complied with each and all of the covenants, agreements and
         conditions required to be performed or complied with on or prior to
         the Closing; (c) no action, suit, proceeding or investigation before
         any court, administrative agency or other governmental authority shall
         be pending or threatened which seeks to restrain, prohibit, invalidate
         or obtain damages as the result of any of the transactions
         contemplated by this Agreement; and (d) all regulatory consents
         required for the Seller to consummate the transactions contemplated
         hereby shall have been granted and such 




                                      11
<PAGE>   12

         consents shall remain in full force and effect, including, but not
         limited to, the FCC grant of the application for assignment of the
         Authorization by Final Order. For purposes of this Agreement, a "Final
         Order" is an FCC action granting an application as to which the time
         for filing for administrative or judicial review or reconsideration or
         for the FCC to set aside such grant on its own motion has expired
         without any such filing having been made or FCC action taken, or, in
         the event of such filing or FCC action, the FCC grant has been
         reaffirmed or upheld and the time for seeking further administrative
         or judicial review with respect thereto has expired without any such
         request for such further review having been filed.

                  (b) Conditions Precedent to Obligations of Seller. Each and
         all of the obligations of Seller to consummate the transactions
         contemplated by this Agreement are subject to fulfillment prior to or
         at the Closing of the following conditions: (a) the representations
         and warranties of Buyer contained herein shall be accurate in all
         material respects as if made on and as of the Closing Date; (b) Buyer
         shall in all material respects have performed all of the obligations
         and complied with each and all of the covenants, agreements and
         conditions required to be performed or complied with on or prior to
         the Closing; (c) no action, suit, proceeding or investigation before
         any court, administrative agency or other governmental authority shall
         be pending or threatened which seeks to restrain, prohibit, invalidate
         or obtain damages as the result of any of the transactions
         contemplated by this Agreement; (d) all regulatory consents required
         for the Buyer to consummate the transactions contemplated hereby shall
         have been granted and such consents shall remain in full force and
         effect, including, but not limited to, the FCC grant of the
         application for assignment of the Authorization by Final Order; (e)
         ATI and Buyer have completely and timely made all monthly payments
         required by the Communications Services Agreement, but without giving
         effect to any increase claimed pursuant to the Seller's Claim, and
         performed all of other obligations of the "Customer" under the
         Communications Services Agreement, and (f) the Fixed Payments shall
         have been paid to Seller in accordance with and to the extent required
         by this Agreement.

                  (c) Disclosure of Breach or Futility. If any party acquires
         knowledge of (i) an event, occurrence or circumstance making
         satisfaction of a condition in Section 8(a) or (b) hereof unlikely,
         the party acquiring such knowledge shall give prompt written notice
         thereof to the other party in sufficient detail to permit a reasonable
         analysis thereof. In the event of a material misrepresentation or a
         material breach of any warranty or covenant made in this Agreement and
         the breaching party's failure to rectify such material
         misrepresentation or material breach within twenty (20) days after
         receipt of written notice thereof from the non-breaching party, then
         the non-breaching party shall have the right, upon written notice to
         the breaching party given within ten (10) days after the expiration of
         said twenty (20)-day period, to terminate this Agreement; provided,
         however, if the non-breaching party does not terminate this Agreement
         by the expiration of said ten (10)-day period, the non-breaching party
         shall be deemed to have waived such misrepresentation or breach.
         Termination of this Agreement pursuant to the preceding sentence shall
         be without prejudice to the non-breaching party's right to seek and
         obtain damages resulting from such misrepresentation or breach. In
         addition, in the event of a material misrepresentation or material
         breach by Seller, the Buyer may, in its discretion, 




                                      12
<PAGE>   13

         seek specific performance of this Agreement in lieu of termination.
         This Section 8(c) sets forth the sole and exclusive remedies of each
         party based on any misrepresentation or breach of this Agreement
         discovered prior to the Closing.

         Section 9. Survival and Indemnification.

                  (a) Survival. All representations, warranties, covenants and
         agreements contained in this Agreement (including any Schedules
         hereto), shall survive the Closing and shall be fully effective and
         enforceable for a period of 12 months following the Closing Date, but
         shall thereafter be of no further force or effect, except as they
         relate to (i) claims for indemnification timely made (pursuant to the
         next sentence), (ii) claims involving fraud on the part of a party
         hereto or (iii) covenants, agreements and claims relating to the
         Deferred Payment. Any claim for indemnification asserted in writing,
         setting forth the nature, basis and amount of the claim in sufficient
         detail to permit a reasonable analysis thereof, within 12 months after
         the Closing Date shall survive until resolved or judicially
         determined; provided, however, once a party has asserted a claim for
         indemnification hereunder, such party must initiate appropriate
         judicial action in a court of competent jurisdiction (or in
         arbitration, if the parties to the dispute over indemnification so
         agree) prior to the latter of (i) the end of the ensuing ninety (90)
         days and (ii) 12 months after the Closing Date, or the claim for
         indemnification shall be deemed to have been waived. The
         representations and warranties set forth in this Agreement shall not
         be affected by any investigation, verification or examination by any
         party hereto or by anyone on behalf of any such party, except as
         specifically set forth herein or in an Exhibit, Schedule or document
         delivered pursuant to this Agreement.

                  (b) Indemnification.

                           (i) Each party shall indemnify and hold harmless the
                  other from and against any and all loss, damage, expense
                  (including court costs, amounts paid in settlement,
                  judgments, reasonable attorneys' fees or other expenses for
                  investigating and defending), suit, action, claim, liability
                  or obligation related to, caused by or arising from any
                  misrepresentation, breach of warranty or failure to perform
                  any covenant or agreement contained herein, together with
                  interest at a floating interest rate equal at all times to
                  the rate of interest publicly announced from time to time by
                  First Union National Bank as its corporate base rate from the
                  date upon which such loss, damage, expense or liability was
                  incurred to the date of payment, plus the amount of all
                  expenses incurred in enforcing this indemnification right,
                  including court costs, reasonable attorney's fees, and other
                  expenses for investigating and defending.

                           (ii) Any party seeking indemnification (the
                  "Indemnified Party") shall give prompt written notice to the
                  indemnifying party (the "Indemnifying Party")of the facts and
                  circumstances giving rise to the claim (the "Notice"). The
                  loss, damage and expense incurred by a party shall be
                  determined on a net after-tax basis and shall take into
                  account any insurance proceeds received by such party.




                                      13
<PAGE>   14

                  (c) Defense Against Asserted Claims. The Indemnified Party
         shall not settle or compromise any claim by a third party for which
         the Indemnified Party is entitled to indemnification hereunder without
         the prior written consent of the Indemnifying Party, unless legal
         action shall have been instituted against the Indemnified Party and
         the Indemnifying Party shall not have taken control of such suit
         within 60 days after notification thereof as provided herein. In
         connection with any claim giving rise to indemnification hereunder
         resulting from or rising out of any claim or legal proceeding by a
         person other than the Indemnified Party, the Indemnifying Party, at
         its sole cost and expense, may, upon written notice to the Indemnified
         Party, assume the defense of any such claim or legal proceeding
         without prejudice to the right of the Indemnifying Party thereafter to
         contest its obligation to indemnify the Indemnified Party in respect
         to the claims asserted therein. If the Indemnifying Party assumes the
         defense of any such claim or legal proceeding, the Indemnifying Party
         shall select counsel to conduct the defense in such claims and legal
         proceedings and at its sole cost and expense shall take all steps
         necessary in the defense or settlement thereof. The Indemnifying Party
         shall not consent to a settlement of, or the entry of any judgment
         arising from, any claim or legal proceeding, without the prior written
         consent of the Indemnified Party, unless the Indemnifying Party admits
         in writing its liability to hold the Indemnified Party harmless from
         and against any losses, damages, expenses and liabilities arising out
         of such settlement and concurrently with such settlement, Indemnifying
         Party pays into the court the full amount of all losses, damages,
         expenses and liabilities to be paid by the Indemnifying Party in
         connection with such settlement and, if such settlement would impose
         or affect ongoing obligations of the Indemnified Party, the
         Indemnified Party consents thereto, which consent shall not be
         unreasonably withheld. The Indemnified Party shall be entitled to
         participate in the defense of any such action with its own counsel and
         at its own expense. If the Indemnifying Party does not assume the
         defense of any such claim or litigation resulting therefrom in
         accordance with the terms hereof, the Indemnified Party may defend
         such claim or litigation in such a manner as it may deem appropriate,
         including settling such claim or litigation after giving notice of the
         same to Indemnifying Party on such terms as the Indemnified Party may
         deem appropriate and any action by the Indemnified Party seeking
         indemnification from Indemnifying Party in accordance with the
         provisions of this Section, Indemnifying Party shall not be entitled
         to question the manner in which the Indemnified Party defended such
         claim or litigation or the amount or nature of any such settlement. In
         the event of a claim by a third party, the Indemnified Party shall
         cooperate with the Indemnifying Party in the defense of such action
         (including making a personal contact with the third party if deemed
         beneficial) and the relevant records of each party shall be made
         available on a timely basis.

                  (d) Failure to Close Because of Default. In the event that
         the Closing is not consummated on or before the earlier of the Closing
         Date or the first anniversary of the date of this Agreement by virtue
         of a default made by a party in the observance or in the due and
         timely performance of any of its covenants or agreements herein
         contained, the parties shall have and retain all of the rights
         afforded them at law or in equity by reason of that default, subject
         to Section 8(c). In addition, Seller acknowledges that the Assets are
         unique, that a failure by either party to complete the transactions
         contemplated by this Agreement will cause irreparable and continuing
         damage to the other party, and that 




                                      14
<PAGE>   15

         actual damages for any such failure may be difficult to ascertain and
         may be inadequate and that the other party will have no adequate
         remedy at law. Consequently, each party agrees that the other party,
         its affiliates, successors and assigns shall be entitled, at such
         party's sole election, to specific performance of any of the
         provisions of this Agreement in addition to any other legal or
         equitable remedies to which such party may otherwise be entitled.

                  (e) Survival. The provisions set forth in this Section 9
         shall survive the Closing. The rights of indemnification set forth in
         this Section 9 shall be the sole and exclusive rights and remedies of
         the parties hereto and their respective affiliates arising out of or
         relating to any misrepresentation or breach of this Agreement
         discovered after the Closing.

         Section 10. Miscellaneous.

                  (a) ATI's Guaranty. ATI hereby guarantees and acts as surety
         for the complete and timely payment, performance and discharge of all
         obligations of Buyer hereunder.

                  (b) Amendments and Waivers. Any term of this Agreement may be
         amended and the observance of any term of this Agreement may be waived
         only with the written consent of (i) both parties in the case of an
         amendment, and (ii) the party waiving any term or condition hereof in
         the case of waiver. Any amendment or waiver effected in accordance
         with this Section shall be binding only in the specific instance for
         the specific purpose for which given.

                  (c) Entire Agreement. This Agreement supersedes any and all
         oral or written agreements and understandings heretofore made relating
         to the subject matter hereof and contains the entire agreement of the
         parties relating to the subject matter hereof. Without limiting the
         generality of the preceding sentence, the parties specifically
         acknowledge that this Agreement contains all of the representations,
         warranties, conditions, covenants and agreements relating to the
         transactions contemplated hereby and to the rights and remedies of the
         parties with respect thereto.

                  (d) Construction; Counterparts. All references herein to the
         masculine gender shall also include the feminine and neuter, and vice
         versa, and all references herein to the singular form shall also
         include the plural, and vice versa, all as the context may require.
         References in this Agreement to particular firms, agencies,
         departments, statutes, regulations and the like shall be considered as
         including references to any successors thereto. The word "include"
         (and correlative terms, such as "includes" and "including") shall be
         construed as if followed by the words "without limitation." All
         references for purposes hereof, in computing the number of days, other
         than "business days," all days shall be counted, including Saturdays,
         Sundays and legal holidays; provided, however, if the final day of any
         time period falls on a date that is not a business day, the final day
         shall be deemed to be the immediately following business day. A
         "business day" means any day that is not a Saturday, Sunday or legal
         holiday in the State of Delaware. This 




                                      15
<PAGE>   16

         Agreement may be executed in one or more counterparts, each of which
         shall be deemed an original, but all of which together shall
         constitute one and the same instrument.

                  (e) Expenses. Each party to this Agreement shall pay its own
         costs and expenses in connection with the transactions contemplated
         hereby. Any sales, transfer or other taxes or fees applicable to the
         conveyance and transfer from Seller to Buyer of the Assets shall be
         borne equally by Seller and Buyer, except that any fees payable to the
         FCC for any application contemplated hereby shall be paid by Buyer..

                  (f) Successors and Assigns. This Agreement shall bind and
         inure to the benefit of the parties named herein and their respective
         successors and assigns. Buyer shall be entitled to assign its rights
         and duties hereunder to any Affiliate with the prior written consent
         of Seller, which shall not be unreasonably withheld, conditioned or
         delayed. Seller shall not be entitled to assign its rights and duties
         hereunder without the prior written consent of Buyer. No assignment
         shall relieve the assignor of any duty or liability hereunder.

                  (g) Applicable Law. This Agreement shall be governed by and
         construed in accordance with the internal laws of the State of
         Delaware.

                  (h) Partial Invalidity. In the event that any provision of
         this Agreement, other than any of the economic terms, shall be held
         invalid or unenforceable by any court of competent jurisdiction, such
         holding shall not invalidate or render unenforceable any other
         provision hereof.

                  (i) Brokers. Each party hereto represents that it has not
         retained any broker or finder or incurred any liability or obligation
         for any brokerage fees, commissions or finders fees with respect to
         this Agreement or the transactions contemplated hereby.




                                      16
<PAGE>   17



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


SELLER                                   BUYER

AESCO Systems, Inc.                      American Telecasting of Portland, Inc.


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

                                         ATI

                                         American Telecasting, Inc.


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



                                      17
<PAGE>   18


                               LIST OF SCHEDULES

Schedule 3(c)(i)    General Assignment and Bill of Sale



<PAGE>   19



                                                               Schedule 3(c)(1)

                          ASSIGNMENT AND BILL OF SALE


         The undersigned, AESCO Systems, Inc. (the "Seller"), for good and
valuable consideration, the receipt of which is hereby acknowledged, does
hereby GRANT, SELL, AND DELIVER to American Telecasting of Portland, Inc., a
Delaware corporation (the "Buyer") its successors and assigns, all of (a)
Seller's rights and interests as the holder of that certain Federal
Communications Commission authorization for the E-Group station in Portland,
Oregon licensed under MMDS Station WHT647 (the "Authorization"), and (b) all
transferable documents and records owned by, held by, or under the control of
Seller used in the operation of said Station (collectively, the "Assets"), and
does hereby ASSIGN, TRANSFER AND CONVEY to the Buyer all of its right, title
and interest in and to the Assets.

         This Assignment and Bill of Sale has been given pursuant to, and to
effect certain transactions contemplated by, that certain Purchase Agreement
dated ______, 1999 by and among Seller, Buyer and American Telecasting, Inc.
The Seller expressly confirms that the representations, warranties, covenants
and agreement set forth in said Purchase Agreement shall survive the execution
and delivery hereof in accordance with its terms.

         IN WITNESS WHEREOF, AESCO Systems, Inc. has caused this Assignment and
Bill of Sale to be executed as of this _____ day of __________________, 1999.


                                     AESCO Systems, Inc.


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


