<PAGE>
                     IMCOR, The Portable Executive Company
                        100 Prospect Street, North Tower
                               Stamford, CT 07901

January 8, 1998

PERSONAL & CONFIDENTIAL

Mr. Geoffrey A. Thompson
Director
Magnavision Corporation
C/O Kohlberg & Co., LLC 111 Radio Circle
Mt. Kisco, NY 10546

Dear Jeff:

Through you as one of its Directors Magnavision Corporation ("Company")
requested that IMCOR, a division or Norrell Services, Inc. ("IMCOR") locate an
individual suuitable to Company to perform certain services as described below
(the "Assignment"). Accordingly, we have introduced Robert E. Hoffman ("IMCOR
Executive") to Company and Company has selected IMCOR Executive to perform the
Assignment. This letter sets forth the Agreement between Company and IMCOR with
respect to the services.

1. ASSIGNMENT

   The Assignment will be for IMCOR Executive to be available to Company to
   function as interim President. In that capacity, IMCOR Executive will be
   responsible to and report directly to the Board. IMCOR Executive has agreed
   to devote his full business time and attention to the Assignment and to be
   available to Company during the entire Assignment.

2. ASSIGNMENT PERIOD

   a) The Assignment Period shall begin on January 8, 1998 and shall continue
      through April 30, 1998 unless terminated or extended as provided below.

   b) Company may terminate the Assignment (i) by hiring IMCOR Executive as an
      employee; or (ii) by giving 30 days' advance written notice on March 31,
      1998 or thereafter to IMCOR and IMCOR Executive of Company's intent to
      terminate the assignment; or (iii) if, in Company's reasonable opinion,
      IMCOR Executive is not performing to Company's requirements.

   c) In the event that Company elects to engage IMCOR Executive to perform
      services in addition to those required with respect to the Assignment or
      desires to extend the Assignment Period beyond the date set forth above.
      Company shall contract for IMCOR Executive's services through IMCOR at
      fees to be mutually agreed upon by Company and IMCOR.

<PAGE>

Mr. Geoffrey A. Thompson                                       January 9, 1998

   d) In the event Company retains IMCOR Executive on an interim basis to
      provide services starting within 12 months after the Assignment or an
      extension thereof has been completed. Company shall contract for IMCOR
      Executive's services through IMCOR at fees to be mutually agreed upon by
      the Company and IMCOR.

   e) At any time during the Assignment Period (or any extensions thereof which
      have been agreed upon by Company, IMCOR Executive, and IMCOR), Company may
      freely negotiate with and hire IMCOR Executive as an employee provided
      Company first gives IMCOR written notice of its intent to do so and
      compensate IMCOR in connection with the employment of IMCOR Executive
      pursuant to the terms and conditions contained in paragraph 3(d) below.

3. COMPENSATION AND PAYMENT TERMS

   a) Company will pay IMCOR $17,500 per month in Assignment Fees, which will
      include IMCOR Executive's and IMCOR's Fees. These fees are based on IMCOR
      Executive being available to Company during working hours which are normal
      for a President.

   b) At the beginning of the Assignment, Company will deposit $17,500 with
      IMCOR. Thereafter, IMCOR will invoice Company for Assignment Fees and
      sales tax, if any, to be paid on or before the 20th day of each month. For
      any partial month, IMCOR will invoice based on a twenty-two business day
      month. An invoice for the first month's Assignment Fees is enclosed. At
      the end of the Assignment, IMCOR will apply the deposit against the final
      invoices, and any balance will be refunded to Company.

   c) Company agrees to promptly reimburse IMCOR Executive for business expenses
      following presentation by IMCOR Executive of appropriate vouchers and/or
      supporting documents as reasonably requested by Company. Company also
      agrees to promptly reimburse IMCOR Executive for the incremental travel
      and interim living expenses specified in Addendum A to this Agreement.

   d) In the event that Company wishes to negotiate with and hire IMCOR
      Executive as an employee at any time during either the initial Assignment
      or its extensions, or within a 12 month period after the completion of
      this Assignment, Company will notify IMCOR of its intentions and shall pay
      IMCOR a Conversion Fee on the first day of IMCOR Executive's employment.

      The Conversion Fee is 30% of IMCOR Executive's Total Annual Compensation
      for the

                                     Page 2
<PAGE>
Mr. Geoffrey A. Thompson                                         January 9, 1998

      first 12 months of employment. The Conversion Fee percentage will be
      reduced by 5% for each three full months of the interim Assignment until
      it reaches 10%.

   e) Company will pay IMCOR a performance bonus of up to 20% of Assignment Fees
      based upon achievement of goals mutually agreed upon by Company, IMCOR,
      and IMCOR Executive at the start of the Assignment and to be described in
      an attached as Addendum B to this Agreement. This bonus shall be paid as
      specified in Addendum B.

4. IMCOR DUTIES AND RESPONSIBILITIES

   a) IMCOR has acted as an intermediary between Company and IMCOR Executive.
      For the duration of the Assignment, IMCOR will be responsible only for
      administrative matters which consist of:
      
      i)   liaison with Company concerning IMCOR Executive's services, including
           the signing of a contract for IMCOR Executive's services;

      ii)  the collection of fees from Company and disbursement of the fees to
           be paid IMCOR Executive;

      iii) withholding and paying of all statutory payroll taxes; and

      iv)  if requested by Company, identifying and introducing, on reasonable
           notice from Company and on mutually agreeable terms, a replacement
           for IMCOR Executive should IMCOR Executive for any reason be unable
           to perform or complete the Assignment; accordingly, the Assignment
           Fees specified in paragraph 3(a) will not be payable for any days
           when an IMCOR Executive is not working.

  b) The relationship between Company and IMCOR is one between Company and an
     independent contractor. The relationship between Company and IMCOR
     Executive is one between Company and independent contractor and not one
     between Company and an employee. As a result, IMCOR Executive shall not be
     entitled to any employee benefits from Company during the term of this
     Assignment. IMCOR agrees to save harmless Company from liability for
     employee benefits, statutory withholding or payroll taxes with respect to
     the Company's relationship with IMCOR Executive during the term of this
     Assignment.

 
5. COMPANY'S DUTIES AND RESPONSIBILITIES

   a) Company, through its own inquiries and interviews with IMCOR Executive, is
      satisfied that IMCOR Executive has the skills, experience and professional
      qualifications to complete the Assignment. Company shall be responsible
      for defining the Assignment with IMCOR Executive, supervising IMCOR
      Executive's actions and monitoring IMCOR Executive's performance. Company
      shall provide IMCOR Executive with such support, including the cooperation
      of the Company's personnel and access to Company's records, as is
      necessary or appropriate to enable IMCOR Executive to complete the
      Assignment during the Assignment Period.

                                     Page 3




<PAGE>

Mr. Geoffrey A. Thompson                                         January 9, 1998

   b) Company will provide a level of indemnification and coverage under any
      applicable employee's, officer's, or director's liability guidelines,
      bylaws or insurance policies for IMCOR Executive's actions as the
      Company's President to the same extent and with the same rights as if
      IMCOR Executive were employed directly as an employee of Company.

   c) Company agrees to indemnify and hold harmless IMCOR and its employees,
      officers, directors and shareholders from any and all liabilities, costs
      or damages (including attorneys' fees) that may arise from the services
      rendered by IMCOR Executive on this Assignment or any extensions thereof,
      except for the gross negligence or willful misconduct of IMCOR.

6. CONFIDENTIALITY

   IMCOR and IMCOR Executive agree that they shall not disclose to any person or
   otherwise use or exploit any information or knowledge relating to Company or
   its business obtained by them at any time as a consequence of this
   Assignment, except to the extent necessary to perform the Assignment
   hereunder. This shall not apply to information which is, or shall be,
   available from third parties who do not have a confidentiality relationship
   with Company.

This letter and its addends constitute the entire Agreement between Company and
IMCOR. This Agreement may not be changed orally. The paragraph headings in this
Agreement are for reference purposes only and shall not in any way affect the
interpretation of this Agreement. This Agreement shall be governed by and
construed under the laws of the State of Connecticut. Company and its directors,
officers, and employees agree to submit to the jurisdiction of the Courts of the
State of Connecticut, Fairfield County, with respect to any dispute arising in
connection with this Agreement.


                                     Page 4


<PAGE>


Mr. Geoffrey A. Thompson                                         January 9, 1998


If the above terms are acceptable, please sign and return to me the enclosed
copy of this Agreement with a check for $17,500 to signify Company's acceptance
of this Agreement.

Sincerely yours,

IMCOR, a division of Norrell Services, Inc.             IMCOR Assignment #4479



By: 
   -------------------------                          ------------------------- 
    Jeffrey R. Belitz                                             Date
    Chief Financial Officer

ACCEPTED AND AGREED:

Magnavision Corporation


By: 
   -------------------------                          ------------------------- 
    Geoffrey A. Thompson                                          Date
    Director

Mr. Geoffrey A. Thompson                                         January 9, 1998



                                     Page 5
<PAGE>

Geoffrey A. Thompson                                        January 9, 1998



                                   ADDENDUM A


This is Addendum A to the Letter of Agreement between IMCOR and Magnavision
Corporation ("Company") dated January 9, 1998.

1. It is hereby agreed that Company will reimburse IMCOR Executive for travel
   expenses between his Virginia Beach, VA home and Wall, NJ for one round trip
   per week. It is acceptable that IMCOR Executive may use the expenses either
   for his own travel to and from his home, or for a family member to use them
   for a visit with IMCOR Executive in Wall, NJ.

2. Company will provide IMCOR Executive with lodging (including telephone) in
   Wall, NJ, either in a furnished condominium, home, apartment, or hotel suite,
   to be selected by IMCOR Executive with Jeff Thompson's approval. Rental
   payments for such lodging should be paid for by IMCOR Executive and will be
   reimbursed by Company.

3. Company will reimburse IMCOR Executive for expenses related to his automobile
   at the rate per mile allowed by the Internal Revenue Service.

4. Company will reimburse normal incremental living expenses, e.g., meals,
   laundry, etc. to IMCOR Executive for the work days in Wall, NJ after
   submission of the Company's normal expense report.

The foregoing Addendum A is hereby agreed and signed in duplicate as of _______.

IMCOR, a division of Norrell Services, Inc.              IMCOR Assignment #4479


--------------------------
Jeffrey R. Belitz
Chief Financial Officer


Magnavision Corporation


---------------------------
Geoffrey A. Thompson
Director

READ & AGREED TO:___________________________________
                            Robert E. Hoffman


                                     Page 6
<PAGE>

Mr. Geoffrey A. Thompson                                        January 9, 1998



                                   ADDENDUM B



This is Addendum B to the Letter of Agreement between IMCOR and Magnavision
Corporation dated January 9, 1998.

         The criteria for awarding the Performance Bonus specified in Paragraph
         3(e) will be attached here before January 31, 1998. The bonus, if
         earned, will be paid upon completion of the Assignment.

The foregoing Addendum B is hereby agreed and signed in duplicate as of________.


IMCOR, a division of Norrell Services, Inc.              IMCOR Assignment #4479


--------------------------
Jeffrey R. Belitz
Chief Financial Officer


Magnavision Corporation


---------------------------
Geoffrey A. Thompson
Director

READ & AGREED TO:
---------------------------
Robert E. Hoffman






                                     Page 7
<PAGE>

                                                               January 9, 1998

                               [IMCOR LETTERHEAD]

PERSONAL & CONFIDENTIAL

Mr. Geoffrey A. Thompson
Director
Magnavision Corporation
C/O Kohlberg & Co., LLC 111 Radio Circle
Mt. Kisco, NY 10546

Dear Jeff:


Through you as one of its Directors Magnavision Corporation ("Company")
requested that IMCOR, a division of Norrell Services, Inc. ("IMCOR") locate an
individual suitable to Company to perform certain services as described below
(the "Assignment"). Accordingly, we have introduced Robert E. Hoffman ("IMCOR
Executive") to Company and Company has selected IMCOR Executive to perform the
Assignment. This letter sets forth the Agreement between Company and IMCOR with
respect to the services.

1. ASSIGNMENT

   The Assignment will be for IMCOR Executive to be available to Company to
   function as interim President. In that capacity, IMCOR Executive will be
   responsible to and report directly to the Board. IMCOR Executive has agreed
   to devote his full business time and attention to the Assignment and to be
   available to Company during the entire Assignment.

2. ASSIGNMENT PERIOD

   a) The Assignment Period shall begin on January 8, 1998 and shall continue
      through April 30, 1998 unless terminated or extended as provided below.

   b) Company may terminate the Assignment (i) by hiring IMCOR Executive as an
      employee; or (ii) by giving 30 days' advance written notice on March 31,
      1998 or thereafter to IMCOR and IMCOR Executive of Company's intent to
      terminate the assignment; or (iii) if, in Company's reasonable opinion,
      IMCOR Executive is not performing to Company's requirement.

   c) In the event that Company elects to engage IMCOR Executive to perform
      services in addition to those required with respect to the Assignment or
      desires to extend the Assignment Period beyond the date set forth above.
      Company shall contract for IMCOR Executive's services through IMCOR at
      fees to be mutually agreed upon by Company and IMCOR.


<PAGE>

[IMCOR LETTERHEAD]


Mt. Geoffrey A. Thompson                                       January 9, 1998

   d) In the event Company retains IMCOR Executive on an interim basis to
      provide services starting within 12 months after the Assignment or an
      extension thereof has been completed, Company shall contract for IMCOR
      Executive's services through IMCOR at fees to be mutually agreed upon by
      the Company and IMCOR.

   e) At any time during the Assignment Period (or any extensions thereof which
      have been agreed upon by Company, IMCOR Executive, and IMCOR), Company may
      freely negotiate with and hire IMCOR Executive as an employee provided
      Company first gives IMCOR written notice of its intent to do so and
      compensates IMCOR in connection with the employment of IMCOR Executive
      pursuant to the terms and conditions contained in paragraph 3(d) below.

3. COMPENSATION AND PAYMENT TERMS

   a) Company will pay IMCOR $17,500 per month in Assignment Fees, which will
      include IMCOR Executive's and IMCOR's Fees. These fees are based on IMCOR
      Executive being available to Company during working hours which are normal
      for a President.

   b) At the beginning of the Assignment Company will deposit $17,500 with
      IMCOR. Thereafter IMCOR will invoice Company for Assignment Fees and sales
      tax if any to be paid on or before the 20th day of each month. For any
      partial month, IMCOR will invoice based on a twenty-two business day
      month. An invoice for the first month's Assignment Fees is enclosed. At
      the end of the Assignment, IMCOR will apply the deposit against the final
      invoices, and any balance will be refunded to Company.

   c) Company agrees to promptly reimburse IMCOR Executive for business expenses
      following presentation by IMCOR Executive of appropriate vouchers and/or
      supporting documents as reasonably requested by Company. Company also
      agrees to promptly reimburse IMCOR Executive for the incremental travel
      and interim living expenses specified in Addendum A to this agreement.

   d) In the event that Company wishes to negotiate with and hire IMCOR
      Executive as an employee at any time during either the initial Assignment
      or its extensions, or within a 12 month period after the completion of
      this Assignment, Company will notify IMCOR of its intentions and shall pay
      IMCOR a Conversion Fee on the first day of IMCOR Executive's employment.

                                       2
<PAGE>

[IMCOR LETTERHEAD]


Mt. Geoffrey A. Thompson                                       January 9, 1998

   The Conversion Fee is 30% of IMCOR Executive's Total Annual Compensation for
   the first 12 months of employment. The Conversion Fee percentage will be
   reduced by 5% for each three full months of the interim Assignment until it
   reaches 10%.

   e) Company will also pay IMCOR a performance bonus of up to 20% of Assignment
      Fees based upon achievement of goals mutually agreed upon by Company,
      IMCOR and IMCOR Executive at the start of the Assignment and to be
      described in and attached as Addendum B to this Agreement. This bonus
      shall be paid as specified in Addendum B.

4. IMCOR DUTIES AND RESPONSIBILITIES

   a) IMCOR has acted as an intermediary between Company and IMCOR Executive.
      For the duration of the Assignment, IMCOR will be responsible only for
      administrative matters which consist of:

       i) liaison with Company concerning IMCOR Executive's services including 
          the signing of a contract for IMCOR Executive's services;

      ii) the collection of fees from Company and disbursement of the fees to
          be paid IMCOR Executive;

     iii) withholding and paying of all statutory payroll taxes; and

      iv) if requested by Company, indentifying and introducing, on reasonable
          notice from Company and on mutually agreeable terms, a replacement for
          IMCOR Executive should IMCOR Executive for any reason be unable to
          perform or complete the Assignment accordingly, the Assignment Fees
          specified in paragraph 3(a) will not be payable for any days when an
          IMCOR Executive is not working.

   b) The relationship between Company, and IMCOR is one between Company and an
      independent contractor. The relationship between Company and IMCOR
      Executive is one between Company and independent contractor and not one
      between Company and an employee. As a result, IMCOR Executive shall not be
      entitled to any employee benefits from Company during the term of this
      Assignment. IMCOR agrees to save harmless Company from liability for
      employee benefits, statutory withholding or payroll taxes with respect to
      the Company's relationship with IMCOR Executive during the term of this
      Assignment.


                                       3


<PAGE>
[IMCOR LOGO]

Mr. Geoffrey A. Thompson                                         January 9, 1998


5. COMPANY'S DUTIES AND RESPONSIBILITIES

   a) Company, through its own inquiries and interviews with IMCOR Executive, is
      satisfied that IMCOR Executive has the skills, experience and professional
      qualifications to complete the Assignment. Company shall be responsible
      for defining the Assignment with IMCOR Executive, supervising IMCOR
      Executive's actions and monitoring IMCOR Executive's performance. Company
      shall provide IMCOR Executive with such support, including the cooperation
      of the Company's personnel and access to Company's records, as is
      necessary or appropriate to enable IMCOR Executive to complete the
      Assignment during the Assignment Period.

   b) Company will provide a level of indemnification and coverage under any
      applicable employee's, officer's, or director's liability guidelines,
      bylaws or insurance policies for IMCOR Executive's actions as the
      Company's President to the same extent and with the same rights as if
      IMCOR Executive were employed directly as an employee of Company.

   c) Company agrees to indemnify and hold harmless IMCOR and its employees,
      officers, directors and shareholders from any and all liabilities, costs
      or damages (including attorneys' fees) that may arise from the services
      rendered by IMCOR Executive on this Assignment or any extensions thereof,
      except for the gross negligence or willful misconduct of IMCOR.

6. CONFIDENTIALITY

   IMCOR and IMCOR Executive agree that they shall not disclose to any person or
   otherwise use or exploit any information or knowledge relating to Company or
   its business obtained by them at any time as a consequence of this
   Assignment, except to the extent necessary to perform the Assignment
   hereunder. This shall not apply to information which is, or shall be,
   available from third parties who do not have a confidentiality relationship
   with Company.

This letter and its addends constitute the entire Agreement between Company and
IMCOR. This Agreement may not be changed orally. The paragraph headings in this
Agreement are for reference purposes only and shall not in any way affect the
interpretation of this Agreement. This Agreement shall be governed by and
construed under the laws of the State of Connecticut. Company and its directors,
officers, and employees agree to submit to the jurisdiction of the Courts of the
State of Connecticut, Fairfield County, with respect to any dispute arising in
connection with this Agreement.


                                     Page 4


<PAGE>
[IMCOR LOGO]

Mr. Geoffrey A. Thompson                                         January 9, 1998


If the above terms are acceptable, please sign and return to me the enclosed
copy of this Agreement with a check for $17,500 to signify Company's
acceptance of this Agreement.

Sincerely yours,

IMCOR, a division of Norrell Services, Inc.             IMCOR Assignment #4479



By: /s/ Jeffrey R. Belitz                               January 9, 1998
   -------------------------                          ------------------------- 
    Jeffrey R. Belitz                                             Date
    Chief Financial Officer

ACCEPTED AND AGREED:

Magnavision Corporation


By: 
   -------------------------                          ------------------------- 
    Geoffrey A. Thompson                                          Date
    Director





                                     Page 5
<PAGE>

[IMCOR LOGO]

Mr. Geoffrey A. Thompson                                         January 9, 1998



                                   ADDENDUM A

This is Addendum A to the Letter of Agreement between IMCOR and Magnavision
Corporation ("Company") dated January 9, 1998.

1. It is hereby agreed that Company will reimburse IMCOR Executive for travel
   expenses between his Virginia Beach, VA home and Wall, NJ for one round trip
   per week. It is acceptable that IMCOR Executive may use the expenses either
   for his own travel to and from his home, or for a family member to use them
   for a visit with IMCOR Executive in Wall, NJ.

2. Company will provide IMCOR Executive with lodging (including telephone) in
   Wall, NJ, either in a furnished condominium, home, apartment, or hotel suite,
   to be selected by IMCOR Executive with Jeff Thompson's approval. Rental
   payments for such lodging should be paid for by IMCOR Executive and will be
   reimbursed by Company.

3. Company will reimburse IMCOR Executive for expenses related to his automobile
   at rate per mile allowed by the Internal Revenue Service,

4. Company will reimburse normal incremental living expenses, e.g., meals,
   laundry, etc. to IMCOR Executive for the work days in Wall, NJ after
   submission of the Company's normal expense report.

The foregoing Addendum A is hereby agreed and signed in duplicate as of
_____________________.

IMCOR, a division of Norrell Services, Inc.               IMCOR Assignment #4479


/s/ Jeffrey R. Belitz
--------------------------------------------
Jeffrey R. Belitz
Chief Financial Officer

Magnavision Corporation



--------------------------------------------
Geoffrey A.Thompson
Director

READ & AGREED TO: -------------------------------------------
                                Robert E. Hoffman



                                     Page 6



<PAGE>
[IMCOR LOGO]

Mr. Geoffrey A. Thompson                                         January 9, 1998


                                   ADDENDUM B


This is Addendum B to the Letter of Agreement between IMCOR and Magnavision
Corporation dated January 9, 1998.





           The criteria for awarding the Performance Bonus spcified in Paragraph
           3(e) will be attached here before January 31, 1998. The bonus, if
           earned, will be paid upon completion of the Assignment.


The foregoing Addendum B is hereby agreed and signed in duplicate as
of________________.


IMCOR, a division of Norrell Services, Inc.               IMCOR Assignment #4479


/s/ Jeffrey R. Belitz
--------------------------------
Jeffrey R. Belitz
Chief Financial Officer



Magnavision Corporation



--------------------------------
Geoffrey A. Thompson
Director


READ & AGREED TO:


--------------------------------
Robert E. Hoffman


                                     Page 7


<PAGE>
                            Nicholas Mastrorilli, Sr.
                             The Wedgewood Building
                           1725 Highway 35 -- Suite B
                             Wall, New Jersey 07719

                                                                 January 8, 1998

VIA FACSIMILE

Board of Directors
Magnavision Corporation

Attention: Mr. A. Geoffrey Thompson

Gentlemen:

      As you are aware, the undersigned is an officer, director and controlling
stockholder of Cacomm, Inc. ("Cacomm"). Cacomm, as you are also aware, is a
significant stockholder of Magnavision Corporation ("Magnavision"), and is a
party to a certain Stockholders Agreement dated as of May 8, 1997 (the
"Stockholders Agreement"), and the undersigned, individually, is a party to a
certain employment agreement with Magnavision dated May 8, 1997 ("Employment
Agreement").

      As you have been advised, The Grand MMDS Alliance, of which Cacomm is a
partner, has recently been granted a license ("License") by the Federal
Communications Commission ("FCC") to construct and operate the four (4) "F"
Group wireless cable frequencies in the New York Market, which License is
subject to various provisions and conditions, one of which requires that the
License be utilized so as to effectuate transmissions on the air in the New York
Market (the "License Territory") in the immediate future. Cacomm currently has
no employees but is owned by approximately one hundred (100) shareholders to
whom the undersigned, as an officer, director and signficant shareholder, has
fiduciary responsibilities.

      As a result of the foregoing, I have come to the conclusion that it is
necessary for me to utilize a substantial portion of my time and attention, in
the fulfillment of such fiduciary responsibilities, to develop the wireless
cable business of Cacomm. In order to do so it will be impossible for me to
function as Chief Executive Officer of Magnavision and given the potential
conflicts of interest between two entities that may compete in the New York
Market on the Internet, Intranet or related wireless cable business, I do not
believe that it is appropriate for me to remain as an employee or an officer or
director of Magnavision while launching competitive activities on behalf of
Cacomm. As a result, and subject to your acceptance of the terms set forth
below, I hereby resign as an officer, director and employee of Magnavision,
effective immediately. Such resignation is subject to the following:

<PAGE>

1.    Magnavision agrees to pay me, in accordance with current practices, my
current base salary, including all health benefits up to the sum of $500 per
month, for the period ending January 8, 1999. In addition, the vesting of 10,765
options granted to me as set forth on Schedule 7(g) of that certain Exchange
Agreement dated as of May 8, 1997 shall not be affected by the actions taken
pursuant to this letter and shall remain in full force and effect in accordance
with the terms thereof, which terms have not yet been determined and are to be
embodied in a Management Incentive Option Plan and related Option Agreement to
be drafted in the future.

2.    Magnavision may only terminate such compensation and benefits (other than
the vested options) if, during the period ending January 8, 1999, I

      (a) became employed by another firm, other than Cacomm or its
subsidiaries;

      (b) enter into a formal employment or consulting agreement with another
firm engaged in wireless or private cable business, other than Cacomm or its
subsidiaries; or

      (c) induce an employee, customer, prospect, supplier or licensee to change
his/her relationship with Magnavision.

3.    Magnavision agrees to issue a press release announcing the substance of
this letter agreement substantially in the form attached.

If the foregoing is acceptable to the Board of Directors of Magnavision, this
letter agreement shall be deemed to supersede the relevant provisions of the
Stockholders Agreement and the Employment Agreement, the remaining provisions
thereof, to the extent applicable, to remain in full force and effect. With
respect to Section 2 of the Stockholders Agreement, on behalf of  Cacomm, I am
authorized to advise you that Cacomm will permit the new Chief Executive Officer
of Magnavision to be chosen by the Board ("New CEO") to occupy one of the three
(3) seats on the Board of Directors to which Cacomm is entitled to designate,
including the right to membership on the Audit, Compensation and Executive
Committees of the Board of Directors of Magnavision, as the representative of
the "Management Directors", as the quoted term is defined in the Stockholders
Agreement; provided, however, that Cacomm shall have the right to appoint one of
its designees as an additional member of each such committee. Cacomm will not,
however, during the period that I have a conflict of interest, appoint the
undersigned as one of its designees to the Board of Directors of Magnavision. It
is understood however that such rights granted to the new CEO are to revert to
Cacomm at the earlier of such time as (i) the "Investor Stock" (as such term is
defined in the Stockholders Agreement) represents less than 20% of the fully
diluted common stock of Magnavision, (ii) the entire Board shall consist of more
than seven (7) persons, and (iii) the holders of the KOCO Stock shall, in the
aggregate, have the right to designate less than four (4) members of the Board
of Directors of Magnavision.

<PAGE>

As you know, members of my family remain as officers, directors, shareholders
and employees of Magnavision and I have a vested interest in the economic
success of Magnavision. Should you wish to call upon me for strategic or other
advice based upon my experience in Magnavision's business, please feel free to
do so. I wish you all the best.

Sincerely,


Nicholas Mastrorilli, Sr.

Agreed and Accepted
Magnavision Corporation

By
   -----------------------------