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EXHIBIT  10.28


THE TERMS OF THIS AGREEMENT AND EXHIBITS ARE PROPRIETARY TO OPTICOM AND ARE
SUBJECT TO A CONFIDENTIALITY AGREEMENT SET FORTH IN SECTION 5 OF THIS AGREEMENT.

THIS AGREEMENT AND THE PRINTED PORTIONS OF ALL EXHIBITS MAY NOT BE AMENDED OR
MODIFIED (OR ANY PART DELETED OR ADDED TO) WITHOUT THE WRITTEN CONSENT OF
OPTICOM'S GENERAL COUNSEL OBTAINED IN ACCORDANCE WITH THE PROVISIONS OF SECTION
21 OF THIS AGREEMENT.


                           OPERATOR SERVICES AGREEMENT
                              (FOR COCOT PAYPHONES)

THIS AGREEMENT, dated January 21, 2000 entered into by and between ONE CALL
COMMUNICATIONS, INC., an Indiana Corporation d/b/a Opticom, of 801 Congressional
Boulevard, Suite 100, Carmel, Indiana, 46032 (herein referred to as "Opticom")
and PHONETEL TECHNOLOGIES, INC., whose address is shown on the last page of this
Agreement (herein referred to as "Customer"),

                                    PURPOSE:

-        Opticom is an operator service provider engaged in the business of
         providing operator long distance services which are more fully
         described on Exhibit "A" which is attached hereto (the "Operator
         Services") through a telecommunications network maintained by it;

-        Customer owns or controls coin-operated pay telephone equipment located
         at various places and sites (herein "COCOT Payphones"), each telephone
         or place where such telephone equipment is located having a discrete
         telephone number which is used to identify the originating location of
         the telephone (herein "ANI"), said COCOT Payphones being sometimes
         herein referred to as either "COCOT Locations" or "Locations" ; and

-        Customer desires to have Opticom provide Operator Services.

-        Customer and Opticom are parties to a Regular Long Distance Service
         Agreement and Standby Operator Services Agreement dated October 26,
         1999 (the "Long Distance and Standby Agreement");

ACCORDINGLY, OPTICOM AND CUSTOMER AGREE AS FOLLOWS:

     1. Contract for Services. Customer hereby contracts with Opticom for
Opticom to provide Operator Services for the telephone equipment at the places
and sites designated from time to time by Customer (herein "Locations"), and
Opticom agrees to provide Operator Services at such Locations in accordance with
the terms and provisions of this Agreement.

     2. Location Information. As to each Location which is to be provided
Operator Services by Opticom, Customer shall provide to Opticom in a form and in
a media mutually acceptable to
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Opticom and Customer all information and data required by Opticom to provide
Operator Services for such Location. All Locations submitted by Customer to
Opticom for Operator Services are subject to approval by Opticom.

     3. Customer Warranty as to Minimum Billings. Customer acknowledges that, in
order to provide Customer Operator Services pursuant to this Agreement, Opticom
will make a substantial investment in facilities and personnel. Accordingly,
Customer warrants that, during each six (6) billing month period commencing with
the first full billing month, the gross billings for Operator Services provided
by Opticom pursuant to this Agreement will average not less than
_________________________________________________________ per month. If, during
any of the four (4) six billing month periods during the term of this Agreement,
the average gross monthly billings for Operator Services during said six (6)
billing month period are less than ____________________________________________,
Customer shall pay to Opticom liquidated damages in the amount of
_______________________________________for each of the billing months during
said six (6) billing month period the actual gross monthly billings for that
month were less than _________________________________________, it being agreed
by the parties that the damages which would be sustained by Opticom would be
substantial but would be difficult of ascertainment. Any liquidated damages
owing by Customer may be deducted by Opticom from commissions and property
surcharges payable to Customer pursuant to this Agreement.

         a. Sale of Business by Customer. If, during the term of this Agreement,
         Customer sells all or substantially all of its assets and if the
         purchaser thereof does not assume and agree to discharge all of
         Customer's obligations under this Agreement and any Addendum thereto
         (or if Opticom is unwilling to consent, for reasonable business
         reasons, to the assignment by Customer to the purchaser of this
         Agreement and any Addendum thereto, all liquidated damages provided for
         in this Section 3 shall, at the option of Opticom, become immediately
         due and payable in full calculated for the entire period from the
         effective date of such sale through the end of the term of this
         Agreement.

     4.  Commissions.

         a. Computation. Commissions payable to Customer are determined based on
         gross billings for Minutes of Use (herein "MOU") charges and Operator
         Assisted Surcharges (herein "OAS charges") billable to third parties
         for Operator Service long distance calls placed from Customer's
         Locations. Charges for MOU are determined by utilizing the Interstate
         and Intrastate Rate Plans selected by Customer for its Locations which
         are set forth on Exhibit B which is attached hereto and made a part
         hereof. Gross commissions are determined by multiplying the commission
         percentages stated on Exhibit B for the Interstate and Intrastate Rate
         Plans applicable to each Location times the gross billings for MOU
         charges and AOS charges for Interstate calls and the gross billings for
         Intrastate calls. Gross commissions are subject to the Bad Debt
         Deduction described in Subsection b below. Billings upon which
         commissions are computed do not include (i) local, state, and/or
         federal taxes which are payable by a billed party for Operator Services
         and (ii) billings for information or directory assistance calls.
         Commissions for calls to Alaska,

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         Hawaii, and Canada which are to be billed to United States telephone
         numbers will be paid at the applicable Intrastate commission rate.

         b. Bad Debt Deduction. Gross commissions and amounts billed for
         Customer's Property Surcharges are subject to a percentage deduction
         ("Bad Debt Deduction") for write-offs on Operator Services billings.
         The Bad Debt Deduction includes deductions and write offs for LEC
         standard bad debt deductions, unbillable and uncollectible calls,
         fraud; credits granted to billed parties upon request; rating changes
         required for billings; and call records which are either unbillable or
         uncollectible for any reason. The application of this deduction to
         gross commissions payable to Customer results in Net Commissions. The
         percentage amounts of the Bad Debt Deductions for billings for
         Interstate and Intrastate MOU charges, OAS charges, and Customer's
         Property Surcharges are stated separately on page 1 of Exhibit B.

         c. Customer's Property Surcharges. Opticom will also pay to Customer
         the Property Surcharges specified on Exhibit B which are to be
         collected by Opticom for Customer less the Bad Debt Deduction described
         above ("Adjusted Property Surcharges").

         d. Payment. Commencing on March 3, 2000, net Commissions and Customer's
         Adjusted Property Surcharges will be paid weekly by wire transfer to
         Customer's designated bank account on or before 11:00 a.m. (E.S.T.) on
         the Friday which follows the end of each Billing Week (12:01 a.m.
         Monday through 12:00 midnight Sunday) based upon Operator Services
         billings rendered by Opticom during the previous Billing Week. Any true
         ups which are necessary shall be made in the third weekly payment each
         month. No commissions and Adjusted Property Surcharges will be payable
         for any billing week for which the total commissions and Adjusted
         Property Surcharges otherwise payable to Customer do not exceed Ten
         Dollars ($10.00), and any such amounts not paid for any month shall not
         carry over to future Billing Weeks

         e. Reports. For each billing month, Opticom will provide to Customer an
         original computer-generated monthly report which will include
         individual call detail for each Operator Services Call made from each
         of Customer's Locations during the billing month. Opticom will use
         reasonable efforts to provide such reports as Customer reasonably
         requests.

         f. Changes in Opticom Billing Rates. Opticom may, from time to time
         with written notice to Customer, change the rates it charges third
         parties for MOU under the Rate Plans selected by Customer and/or the
         amount of Operator Surcharges payable to Opticom by such third parties
         for Operator Services provided by Opticom. Customer shall have a right
         to terminate this Agreement upon not less than thirty (30) days written
         notice to Opticom if Opticom makes any change in such billing rates
         which has a material adverse effect upon Customer and its business.

     5. Confidentiality. The parties hereto agree to keep and maintain the terms
and provisions of this Agreement in confidence, and Opticom agrees to keep and
maintain the names, addresses, and ANI's of all of Customer's Operator Service
Locations, confidential and not to disclose the

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same to any third party except for such disclosure as may be compelled by legal
process or required by any regulatory agency having jurisdiction and such
disclosure as may be necessary in order for Opticom to arrange for Operator
Services for such Locations. Opticom acknowledges and agrees that information
provided and submitted by Customer to Opticom as the identity of owners and
operators of Locations is and shall always remain confidential information
subject to the provisions of this section of this Agreement, and Opticom agrees
that at no time will it utilize such confidential information for any purpose
other than to arrange to provide Operator Services to such Locations for
Customer pursuant to this Agreement, nor will Opticom disclose such confidential
information to any other person, firm, corporation or other entity without the
express written consent of Customer.

     6. Term of Agreement. The initial term of this Agreement shall be for a
period of twenty-five (25) months commencing on the date hereof after which this
Agreement shall continue on a month-to-month basis until terminated by either
party on not less than thirty (30) days written notice.

     7. Quality of Service. Opticom agrees to provide the Operator Services
hereunder to Customer's Locations in conformity with the appropriate industry
standards for like services and in accordance with the performance standards set
forth on Schedule 1 which shall be signed and dated by both parties and attached
hereto.

     8. Branding. At Customer's option, all operator calls handled by Opticom
from Customer's COCOT Locations will be branded in Customer's name.

     9. 211 Trouble Calls. Opticom will answer, respond to, and process 211
trouble reports ("211 Calls") from Customer' COCOT Locations. Opticom will also
process requests for refunds and requests for credits ("Home Credits"). Customer
shall pay a fee of ______________________________ per trouble ticket to process
Home Credits, and Customer shall also pay all of Opticom's costs and expenses
incurred in processing and paying refunds and in granting credits. To foster
public relations, all callers will be offered a courtesy long distance call of
three (3) minutes in duration without charge to the caller. For those callers
accepting such a courtesy call, Customer will be charged a fee of
_____________________________________ per call. Up to five hundred (500)
completed trouble ticket calls (including those trouble ticket calls which
involve courtesy calls) will be provided for Customer each month without charge
at no cost to Customer. If the number of 211 Calls processed by Opticom in any
month is in excess of five hundred (500), Customer shall pay a charge of
___________________ for each 211 Call in excess of the five hundred (500). Those
trouble reports which include courtesy calls will be counted as part of the
monthly free five hundred (500) call ceiling. All charges owing by Customer to
Opticom for trouble reports will be deducted from commissions and property
surcharges payable to Customer pursuant to this Agreement.

     10. Letters of Authorization ("LOA's"). Prior to Opticom commencing
Operator Services for any Location which is not owned by Customer ("Non-Owned
Location"), Customer shall obtain an authorization ("Authorization") from such
Location which either directly authorizes Opticom to provide service to the
Location or authorizes Customer, as agent for the Location, to select an
operator services provider, such as Opticom, to provide operator long distance
services for such

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Location. Such authorization shall comply with (i) all applicable local, state,
and federal regulations (ii) all requirements and procedures of the local
operating company (LEC) with respect to the selection of a preferred
interconnection long distance carrier for the Location and (iii) all procedures
and requirements of Opticom. As to all Non-Owned Locations submitted by Customer
to Opticom, Customer represents and warrants that Customer has obtained for the
Location an Authorization which complies with the requirements of this
Agreement, that such Authorization is valid and authentic and constitutes and
represents the most current Authorization for said Location to the best of
Customer's knowledge, and Customer agrees to and shall indemnify and hold
harmless Opticom from and against all losses, claims, fines, penalties, and
expenses (including reasonable attorney fees) asserted or levied against or
sustained or incurred by Opticom arising from or related to the invalidity of
any Authorization or the contention that such Authorization was superseded by a
more recent Authorization. As to all Locations owned by Customer (COCOT's),
Customer represents and warrants to Opticom that the telephone equipment at such
Locations to be served by Opticom pursuant to this Agreement is owned by
Customer and that Customer has the power and authority to select the operator
service provider for such Locations without the consent, approval, or
authorization of any other person, firm, corporation, or other entity, and
Customer agrees to and shall indemnify and hold harmless Opticom from and
against all claims, liabilities, damages, fines, penalties, or other costs and
expenses, including reasonable attorney fees, incurred or paid by Opticom
arising out of or which involves, in any manner, the contention of a third party
(i) that Customer is or was not the owner of the COCOT telephone equipment at
such Locations or (ii) that Customer did not have the power and authority to
select the operator service provider for such Locations without the consent,
approval, or authorization of any other person, firm, corporation, or other
entity. In the event another customer of Opticom presents to Opticom an
Authorization for a Location which is then subject to Customer's Authorization
or in the event Customer presents to Opticom an Authorization for a Location
which is then subject to an Authorization of another customer of Opticom,
Customer authorizes and empowers Opticom, in its sole and absolute discretion
exercised in good faith pursuant to internal Opticom policies consistently and
uniformly applied, to determine which Authorization is to be honored.

     11. Regulatory Matters. Customer and all Location owners and/or operators
shall at all times comply with and conform to all federal, state, and local
laws, rules, regulations, ordinances, tariffs, dockets, orders, and guidelines
applicable to the Operator Services to be provided by Opticom hereunder
including all requirements with regard to posting guidelines, alternate carrier
access, branding, transfer of calls to local exchanges, screening, blocking, and
routing of emergency calls.

     Customer and all Locations shall permit Opticom to take whatever steps are
necessary to insure that Opticom is in compliance with all of the regulations
and requirements pertaining to the provision of Alternate Operator Services as
established by the Federal Communications Commission and the regulatory
authority(ies) of the state wherein such services will be provided.

     Opticom and Customer shall each indemnify, defend, and hold the other
harmless of and from any and all claims, liabilities, fines, penalties, or other
costs and expenses, including reasonable attorney fees, incurred or paid by such
party by reason of the other party's failure to

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comply with any applicable federal or state laws, rules, regulations, tariffs,
dockets, laws, ordinances, orders, or guidelines or other regulatory
requirements applicable to such party.

     12. Access and Other Charges. Customer shall be responsible for all
Presubscribed Interexchange Carrier Charges imposed with regard to Customer's
Locations and the telephone lines serving such Locations; any FCC Universal
Service Fund Contributions and Assessments levied and imposed upon Customer as a
telecommunications provider; and any other similar charges and assessments which
may be due and payable with regard to either Customer's telephone lines and
equipment or with regard to the telecommunications services provided by Customer
at its Locations.

     13. Location Relations. Customer acknowledges that, by reason of regulatory
requirements requiring the identification of Opticom as the Operator Services
Provider at Locations, the persons who own or control Locations will likely
contact Opticom in the event there exist unresolved problems between the
Locations and Customer regarding the payment of commissions by Customer for the
Location or other matters and that the industry reputation of Opticom may be
adversely affected if such problems are not satisfactorily resolved in an
expeditious manner. Customer agrees to promptly endeavor to satisfactorily
resolve problems with Location owners and operators which are brought to
Customer's attention by Opticom, and Customer agrees that, if Customer fails to
promptly resolve such complaints, Opticom may take whatever measures it deems
appropriate to resolve the problem and maintain its reputation in the industry.

     14. Suspension and Termination of Services. Opticom shall have the right at
any time and from time to time, with as much notice to Customer as is
practicable under the circumstances, to temporarily suspend or terminate all or
some Operator Services provided at or to any Location because of (i) defects or
malfunctions of or in subscriber equipment at the Location over which Opticom
has no control; (ii) an unacceptable level of fraudulent or uncollectible
telephone calls; (iii) for violations of local, state, or federal laws and
regulations; (iv) for violations of published rules, regulations, and tariffs;
(v) an unacceptable quality of transmission by reason of factors over which
Opticom has no control; (vi) abuse of the Operator Services provided hereunder;
or (vii) compliance with any order of a regulatory agency having jurisdiction.

     15. Relationship of the Parties. Opticom and Customer are independent
parties, and there exists no relationship of joint venture, partnership, or
agency between them. Customer and Opticom each agree to indemnify, defend, and
hold each other harmless from all losses, claims, costs, including reasonable
attorney fees, damages, or expenses arising out of, in whole or in part,
directly or indirectly, the acts or omissions of such party or persons acting
for or on its behalf.

     16. Force Majeure. To the extent that either Customer or Opticom shall be
prevented or delayed from performing hereunder or giving any notice because of
any event or circumstance over which such parties have no reasonable control
(including, without limitation, war, fire, civil commotion, strike, flood, power
shortages or outages, communication breakdowns and outages, acts or orders of
regulatory agencies having jurisdiction, and the like), then such party shall be
excused from performing or giving such notice for the duration of such event or
force majeure,

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provided, however, that if the duration of the delay caused by such event shall
exceed thirty (30) days, the party who was to benefit from the performance of
such act shall have the right to terminate this Agreement by giving written
notice to the other party.

     17. Default and Termination. In addition to all other rights of termination
as herein provided, both Customer and Opticom shall have a right to terminate
this Agreement by reason of any material default in the performance of duties
and responsibilities by the other party if such default is not cured within
thirty (30) days after written notice of such default is given to the defaulting
party. Other than for (i) obligations for the payment of money or commissions
due pursuant to this Agreement, (ii) indemnity obligations which are expressly
provided for in this Agreement, (iii) confidentiality obligations under Section
5 of this Agreement, and (iv) amounts or damages (liquidated or otherwise) for
which either party is liable pursuant to the terms and provisions of any
addendum to this Agreement, any loan agreement between the parties, or any other
agreement which supplements this Agreement (all of which obligations shall
survive termination of this Agreement), neither party hereto shall have any
liability to the other party for any direct, indirect, incidental,
consequential, punitive or other damages sustained by a party by reason of the
default of the other party under this Agreement, it being agreed that
termination of this Agreement shall be the sole recourse and remedy of a
non-defaulting party for the default of the other party.

     In the event (i) this Agreement is terminated by Opticom for any reason,
(ii) this Agreement terminates at the end of any term by reason of the election
of either party not to permit this Agreement to renew for another term, or (iii)
Opticom elects to terminate Operator Services for any Location of Customer for
any reason, Customer shall be responsible for diligently and timely changing,
prior to the effective date of any such termination, the preferred
interconnection carrier from Opticom to another operator services provider for
all Locations of Customer affected by any such termination. If Customer fails to
change the preferred interconnection carrier for any Location prior to the
effective date of the termination of this Agreement or termination by Opticom of
such Location(s) and such Location(s) remains on Opticom's Operator Services
network after the effective date of termination, no commissions or property
surcharges will be payable to Customer for any Operator Services provided by
Opticom for such Location after the effective date of the termination. As to all
Locations of Customer which remain on Opticom's Operator Services network
following termination of this Agreement or termination by Opticom of such
Location(s), Customer agrees to and shall indemnify, defend, and hold Opticom
harmless of and from any and all claims, liabilities, fines, penalties, or other
costs and expenses, including reasonable attorney fees, incurred or paid by
Opticom by reason of the Customer's failure (i) to change the preferred
interconnection carrier for such Location(s) or (ii) to comply with any
applicable federal or state laws, rules, regulations, tariffs, dockets, laws,
ordinances, orders, or guidelines or other regulatory requirements applicable to
Customer and such Locations, Customer expressly agreeing that this indemnity
obligation shall survive termination of this Agreement.

     18. Changed Business and Economic Conditions. The parties hereto recognize
and affirm that the Commission Schedules set forth on Exhibit B are based upon
current business and economic conditions in the telecommunications industry in
the United States and that such business and economic conditions may adversely
change in the future by reason of competition,

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industry consolidation, governmental regulation, loss by Opticom of current
network facilities or arrangements, and factors which are beyond the control of
Opticom. The parties further recognize that changed business and economic
conditions may make it uneconomical and impractical, with regard to existing
Commission Schedules, for Opticom to profitably accept new Locations, to
profitably continue to provide some Operator Services, to profitably continue to
serve some or all existing Locations, and to otherwise be profitably competitive
in the marketplace with regard to existing and future Locations. In the event
bona fide changed business and economic conditions do occur and Opticom, in good
faith, determines that it is uneconomical and impractical, in relation to
existing Commission Schedules, for Opticom to profitably serve some or all
existing Locations and to accept new Locations and to otherwise be profitably
competitive in the marketplace with regard to some or all existing Locations and
future Locations, Opticom may give Customer written notice of such situation and
may, on sixty (60) days' notice to Customer, terminate some or all existing
Locations or some Operator Services provided to Locations, in which event
Customer's right to receive commissions as to such terminated Locations or
terminated Operator Services shall cease, and Customer shall have no recourse
against Opticom for loss of commissions occurring by reason of Opticom's
termination of such Locations or services, but Opticom shall remain accountable
to Customer for all commissions for Operator Services usage by such terminated
Locations prior to the effective date of termination. In any such situation,
Opticom agrees to negotiate in good faith with Customer regarding a new mutually
satisfactory arrangement between Customer and Opticom pursuant to which the
termination of existing Locations or Operator Services may be avoided and new
Locations can be accepted. In the event the parties are unable to reach a new
mutual agreement within a reasonable period of time, Customer may terminate this
Agreement on not less than thirty (30) days written notice to Opticom

     19. Bankruptcy. In the event either Opticom or Customer becomes bankrupt
(files a petition in bankruptcy or has an involuntary petition in bankruptcy
filed against them and said petition is not dismissed within sixty (60) days of
such filing), the other party may elect to terminate this Agreement by written
notice effective at the end of the calendar month such notice was given. If
Opticom becomes bankrupt, all commissions owing to Customer shall become
immediately due and payable and Customer may immediately commence to transfer
Locations to another operator services provider, in which event this Agreement
shall continue in full force and effect as to all matters, including commissions
for Customer, as to all Locations which remain on Opticom's network for as long
as they remain on Opticom's network. In the event Customer becomes bankrupt,
Opticom may, at its option, make advances to Locations for unpaid commissions,
surcharges, and other compensation owing to such Locations by Customer in order
to maintain such Locations on Opticom's network, and, if Opticom does so,
Opticom may repay itself for such advances out of commissions due and payable to
Customer for business arising subsequent to the date Customer became bankrupt.

     20. Arbitration. Except as may be expressly provided otherwise in an
addendum to this Agreement or in any other agreement which is entered into be
the parties to this Agreement, all claims or disputes arising out of this
Agreement, the relationship of the parties created by this Agreement, or the
alleged breach thereof shall be decided by arbitration in accordance with the
Commercial Arbitration Rules of the American Arbitration Association then
obtaining unless the parties mutually agree otherwise. Notice of the demand for
arbitration shall be submitted in

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writing to the other party and to the American Arbitration Association. All
arbitration proceedings and hearings shall be held in Indianapolis, Indiana. Any
arbitration award shall be binding and enforceable in any court having
jurisdiction of the parties hereto. The cost of the arbitration proceeding,
exclusive of each party's own attorney fees and out-of-pocket expenses, shall be
borne equally by the parties. If the provisions of any addendum or other
agreement between the parties provides for an alternate means of dispute
resolution (including litigation in a court of law), the provisions of such
addendum or other agreement shall supersede this agreement with regard to the
resolution of the claims arising out of or under such addendum or other
agreement.

     21. Modification and Amendment. The advance written approval of Opticom's
General Counsel shall be required to amend, modify, or add to this Agreement,
the printed portions of all attached exhibits, and any approved Addendum
thereto. To be effective, such written approval must be endorsed in writing on
this Agreement or by way of an attachment hereto. Any modification or amendment
(or any deletion from or addition to) the form of this Agreement, its exhibits,
or any addendum to this Agreement not so approved in writing by such General
Counsel shall be void and of no effect even if signed by an officer of Opticom.
No officer, employee, sales representative, or agent of Opticom other than its
General Counsel has the authority to vary or modify the form of this Agreement,
the printed portions of the exhibits, or any approved addendum or to otherwise
agree or consent to any amendment or addendum thereto. Opticom's General Counsel
is:

                                   Jeffrey R. Kinney, Esq.
                  Mailing Address: 1 Riverfront Place, 20 N.W. First Street,
                                   Suite 700, Evansville, IN  47708
                  Courier Address: same as above
                  Telephone Number:(812) 425-5200
                  Fax Number:      (812) 425-2464
                  E-Mail:          jkinney@kylaw.com

     22. Notices. Any notice either party desires to give to the other party
hereunder shall be in writing and shall be delivered by first class United
States mail, postage prepaid, addressed to the parties at their addresses set
forth below unless such addresses are changed by written notice from time to
time. Written notices may also be faxed to either party, but, to be effective,
the notice must also be mailed as aforesaid.

                  If to Opticom:    One Call Communications, Inc.
                                    801 Congressional Boulevard, Suite 100
                                    Carmel, Indiana  46032
                                    Attn:  President
                                    Fax Number:  (317) 575-3231

                  If to Customer:  To the Customer at the address set
                                   forth below.

     23. Non-Waiver. No term or provision of this Agreement shall be deemed
waived and no breach or default shall be deemed excused unless such waiver or
consent shall be in writing and

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signed by the party claimed to have waived or consented. No consent by any party
to, or waiver of, a breach or default by the other, whether express or implied,
shall constitute a consent to, waiver of, or excuse for any different or
subsequent breach or default.

     24. Assignment. This Agreement may not be assigned by Customer except with
the written consent of Opticom, which consent shall not be unreasonably
withheld, provided,however, Customer may, without Opticom's consent, assign its
rights to receive payment of commissions and Property Surcharges to secure
financial obligations of Customer.

     25. Governing Law. This Agreement and any dispute relating thereto shall be
governed by the laws of the State of Indiana.

     26. Binding Effect. This Agreement shall be binding upon and inure to the
benefit of the successors and permitted assigns of the parties.

     27. Headings and Titles. The headings and titles in this Agreement are for
convenience of reference only and shall not be construed to define or limit any
of the terms herein or affect the meanings or interpretations of this Agreement.

     28. The Long Distance and Standby Agreement and Other Agreements. The Long
Distance and Standby Agreement is terminated as of the date of this Agreement.
This Agreement shall supersede and replace all existing arrangements or
agreements between Opticom and Customer for the provision of telecommunications
services by Opticom for Customer.

29. Execution; Counterparts; Facsimile Delivery. A copy of this Agreement signed
by one party which is received by the other party by means of a facsimile
transmission made by the signing party shall be binding upon the signing party
and shall constitute delivery of this Agreement by the signing party for all
purposes. The exchange by the parties of duly signed counterpart copies of this
Agreement transmitted by such parties to each other by facsimile transmission
shall result in a legally enforceable contract binding upon both parties.


                         THE FOREGOING IS OUR AGREEMENT.


ONE CALL COMMUNICATIONS, INC.                PHONETEL TECHNOLOGIES, INC.

By:/s/ Brad Benge                            By:/s/ John D. Chichester
     Executive Vice President                    President

                                             Address: North Point Tower
                                                      1001 Lakeside Avenue
                                                      Seventh Floor
                                                      Cleveland, OH  44114


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                                   EXHIBIT "A"


     The following is a listing of types of Opticom services available at this
time.

     All long distance billable calls (InterLATA, IntraLATA, and/or Interstate),
     except as noted below, which are originated from Customer's Locations, but
     which either (i) are not billed to Customer or to the Location, and/or (ii)
     require operator assistance, including, but not limited to:

            (a)   Operator assisted calls utilizing participating Bell Operating
                  Company ("BOC") calling cards and other calling cards issued
                  by other operating companies;

            (b)   Operator assisted calls utilizing participating commercial
                  credit cards;

            (c)   Collect calls;

            (d)   Calls which are billed to third party telephones;

            (e)   Person-to-Person Credit Card and/or Calling Card calls;

            (f)   0 + Area Code + seven digits + credit cards ("0+") listed (a)
                  and (b) above;

            (g)   0 without additional digits ("0-").


     Services to be provided by Opticom do not include Local Operator Services
     which shall mean telephone calls (local collect, local person-to-person
     collect, local billed to a calling card, local third party person-to-person
     calls billed to another number) which are originated in and terminate in a
     geographic area which is a toll free local calling area. If Customer's
     Locations are used for Local Operator Services which cannot be billed by
     Opticom on an elapsed time basis, the difference between the charge allowed
     to be collected by Opticom and the elapsed time charges shall be deducted
     from amounts payable to Customer.

     Operator Services for International Long Distance Calls from Customer's
     Locations may be arranged for by Customer pursuant to an Addendum to the
     Operator Services Agreement.


                                       11
<PAGE>   12
                                   EXHIBIT B                        Page 1 of 4



                   COMMISSION AND PROPERTY SURCHARGE SCHEDULES

The commission percentage rate specified below for each of the Interstate and
Intrastate Rate Plans (Billing Groups) selected by Customer for its Locations
used to determine the amount of commissions payable to Customer is applied to
Adjusted Billings for Minutes of Use ("MOU") charges and operator assisted
surcharges ("OAS charges") for Interstate or Intrastate Telephone Calls made
from Customer's Locations under each of the Rate Plans applicable to such
Locations. Customer may select any of the Rate Plans for different Locations,
but only one Interstate and one Intrastate Rate Plan may be selected for a
Location. Opticom will bill and, subject to the applicable Bad Debt Deduction,
collect for Customer the Property Surcharges ("PIF") specified below for each
completed Interstate and, where applicable, Intrastate Long Distance Call.

                              INTERSTATE RATE PLANS

                  The Interstate Bad Debt Percentage is ______%

            / /   Check here if Tiered, Volume-Sensitive Commission Rate Plans
                  are attached and are to to be used in lieu of the following
                  Interstate Rate Plan Schedule.
<TABLE>
<CAPTION>

                                       Billing
         Rate Plans                     Group
         ----------                     -----
<S>                                   <C>
         Optibase                         115

         New Optibase-Day                 116

         Old Optibase-Day                 117

         Optimize                         119

         Optfive                          120

         Optiplus                         121

         Optimum                          123


         Optispan                         125

         Opti75                           126

         Optimax                          127

         Optibest                         138

         Other

         Other

         Other

</TABLE>
<PAGE>   13
                                                                     Page 2 of 4


                              INTRASTATE RATE PLANS

                  The Intrastate Bad Debt Percentage is ______%

A Customer may elect to use either (i) the General Intrastate Rate Plan which is
set forth below for all States in which the Customer does business or (ii) the
State-specific Rate Plans which

      are set forth one the following pages or (iii) a combination of both.


/ /  Check here if the General Intrastate Rate Plan is to be used in all States

/ / Check here if the General Intrastate Rate Plan is to be used in all states
EXCEPT for those states for which information is completed on the following
pages for state-specific rate plans.

                   GENERAL INTRASTATE RATE PLAN FOR ALL STATES

               Billing Group                         Commission Rate
<PAGE>   14
                             INDIVIDUAL STATE RATE PLANS            Page 3 of 4

Instructions: Complete Commission Rates ONLY for rate plans in states where (i)
Customer will do business or (ii) those states where Customer does not want the
General Intrastate Plan to be used.
<TABLE>
<CAPTION>
                              Billing
        State                 Group
        -----                 -----
<S>                          <C>
     Alabama                  18
     Alaska                   18
     Arizona                  18
     Arkansas                 18
     California               18
                              10
                               7
                              20
     Colorado                 18
                              28
     Connecticut
     DC (see Washington, DC)
     Delaware                 18
     Florida                  18
                              44
     Georgia                  18
     Hawaii                   18
     Idaho                    18
     Illinois                 18
                               2
                              57
     Indiana                  18
                               7
     Iowa                     18
     Kansas                   18

     Kentucky                 18
     Louisiana                18
     Maine                    18
     Maryland                 18
     Massachusetts            18
     Michigan                 18
                              32
                              31
     Minnesota                18
     Mississippi              18
     Missouri                 18
                              40
     Montana                  18
                              17
                              40
     Nebraska                 18
     Nevada                   18
     New Hampshire            18
                              22
     New Jersey               18
                              38
                              55
     New Mexico               18
     New York                 18
     North Carolina           18
                             151

     North Dakota             18
     Ohio                     18
     Oklahoma                 18
                             150
                              35
     Oregon                   18
                              39
     Pennsylvania             18
     Rhode Island             18
     South Carolina           18
     South Dakota             18
     Tennessee                18
     Texas                    18
                              43
                              53
     Utah                     18
     Vermont                  18
     Virginia                 18
                               9
     Washington               18
                              39
     Washington, DC           18
     West Virginia            18
     Wisconsin                18
     Wyoming                  18
</TABLE>

                               BILLING GROUP NOTES

Billing Group 7--Confinement Facilities
Billing Group 18--Pay Telephones in Cal and Virginia
Billing Group 22--Customer-Owned Pay Telephones (COCOT's) in NH
Billing Group 39--Local Default for OR and WASH
Billing Groups 43 or 53--Pay Telephones in Tex
Billing Group 44--Customer-Owned Pay Telephones (COCOT's) in Fla


<PAGE>   15
                     INTERSTATE PROPERTY SURCHARGES (PIF)           Page 4 of 4


Interstate Property Surcharges are subject to the Bad Debt Deduction percentage
stated on Page 1 of this Exhibit B.

/ /  Check here if a Ramp-Up Interstate Property Surcharge (PIF) schedule is
      attached and is to be used in lieu of the following-stated Interstate
      Property Surcharge amount.

Amount of Interstate Property Surcharge (PIF) per completed Interstate call
$_______________

/ /   Check here if the Interstate Property Surcharges are to vary in amount
      from Location to Location as designated in writing by Customer. (If this
      is applicable, the amount of the Interstate Property Surcharge for any
      Location may not exceed the Property Surcharge amounts stated above.)

                         INTRASTATE PROPERTY SURCHARGES

Property Surcharges for Intrastate Long Distance Operator Service Telephone
Calls may be prohibited in some states, limited in amount in other states,
further restricted in some states as to (i) the types of telephones utilized to
make such calls, eg. only pay telephones, only COCOT pay telephones, etc., (ii)
the places where the telephone is located, eg. only hotel and motel rooms, only
hospitals, no confinement facilities, etc., (iii) the locale where the telephone
equipment is located, eg. New York City, (iv) whether such calls are IntraLata
or InterLata, and (v) other variables. Customer may elect to have billed the
maximum Intrastate Property Surcharge permitted in the state(s) where Customer's
Locations are located or a lesser amount. Intrastate Property Surcharges are
subject to the Intrastate Bad Debt Deduction percentage stated on Page 1 of this
Exhibit B.

/ / Check here if the authorized Intrastate Property Surcharges are to vary in
amount from Location to Location as designated in writing by Customer.

/ /  Check here if Opticom is to bill the maximum authorized Intrastate Property
     Surcharge for all of Customer's Locations to the extent permitted by law in
     each state where Customer has Locations.

/ / Check here and complete the following table if the following Intrastate
Surcharges are to be uniformly billed in the following States for the following
types or classes of telephones, places, or locales to the extent permitted by
law. Use more than one line for each state if necessary. (The use of this table
will not prevent Customer from varying the amount of the surcharge for certain
Locations as designated in writing by Customer.)
<TABLE>
<CAPTION>

                          Type of Telephone                  Amount of
                            or Locations                    Intrastate
                        (eg. COCOT, payphone,                Property
       State              hotel/motel, NYC)                  Surcharge
       -----              -----------------                  ---------
<S>                     <C>                               <C>

                                                           $
</TABLE>