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                                                                Exhibit 10.2

                                                              August 4, 1998

                                                                 $500,000.00


                           DEMAND PROMISSORY NOTE

     AMNEX, INC., a New York corporation ("AMNEX") and AMERICAN NETWORK
EXCHANGE, INC., a Delaware corporation and wholly-owned subsidiary of AMNEX
("ANEI"), (collectively the "Makers"), for value received, hereby jointly
and severally promise to pay to the order of ROTTERDAM VENTURES, INC., a New
York corporation (the "Holder"), within fifteen (15) days following the date
of receipt of demand for payment (the "Due Date"), at the offices of the
Holder indicated in paragraph 5 hereof the aggregate principal sum of FIVE
HUNDRED THOUSAND DOLLARS ($500,000) in such coin or currency of the United
States of America as at the time of payment shall be legal tender for the
payment of public and private debts and to pay interest on such principal
sum from the date hereof at a fluctuating rate per annum at all times equal
to the prime rate of interest announced from time to time by The Chase
Manhattan Bank plus two percent (2%) (the "Note Rate"). Accrued interest on
the unpaid principal balance of this Demand Promissory Note ("Note") shall
be payable on the first business day of each month commencing September 1,
1998, and on the Due Date.

     1. Registered Owner. The Makers may consider and treat the person in
whose name this Note shall be registered as the absolute owner thereof for
all purposes whatsoever (whether or not this Note shall be overdue) and the
Makers shall not be affected by any notice to the contrary. The registered
owner of this Note shall have the right to transfer it by assignment and the
transferee thereof upon his registration as owner of ths Note, shall become
vested with all the powers and rights of the transferor. Registration of any
new owner shall take place upon presentation of this Note to AMNEX at its
offices together with an assignment duly authenticated. In case of transfers
by operation of law, the transferee shall notify the Makers of such transfer
and of his address, and shall submit appropriate evidence regarding the
transfer so that this Note may be registered in the name of the transferee.
This Note is transferable only on the books of the Makers by the holder
hereof in person or by attorney, on the surrender hereof duly endorsed.
Communications sent to any registered owner shall be effective as against
all holders or transferees of this Note not registered at the time of
sending the communication.

     2. Redemption. The Makers shall be required to redeem the Note upon
receipt of proceeds from a financing between Jackson National Life Insurance
Company, Crescent Public Communications Inc. and Sun Tel North America, Inc.
Additionally, the Holder, by its acceptance of this Note, hereby
acknowledges that, at any time, and from time to time, notwithstanding the
lack of demand for payment on the part of the Holder, any of the Makers may,
at its option, by written notice given to the Holder, elect to redeem and
prepay all or any portion of the outstanding principal indebtedness
evidenced by this Note, together with accrued interest thereon, without
premium or penalty. Any such notice of a Maker's election to redeem and
prepay as provided for hereinabove shall be given not less than five (5)
days prior to the date fixed in such notice as the date for redemption of
this Note (the "Redemption Date").

     3. Default Rate of Interest; Late Charge. In the event the Makers shall
fail to pay all or any portion of the principal amount hereof on or before
the Due Date, any such unpaid amount shall bear interest, for each day from
the Due Date, until paid in full, at a fluctuating rate per annum at all
times equal to the Note Rate plus five percent (5%) instead of the Note Rate
as hereinabove provided, payable upon demand. In the event the Makers shall
fail to pay timely any other amount due hereunder, the Makers, jointly and
severally, agree to make a payment, in addition to all other required
payments hereunder, equal to two percent (2%) of the overdue payment.


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     4. Applicable Law. This Note is issued under and shall for all purposes
be governed by and construed in accordance with the laws of the State of New
York, excluding choice of law rules thereof.

     5. Notices. Any and all notices or other communications or deliveries
required or permitted to be given or made pursuant to any of the provisions
of this Note shall be in writing and shall be deemed to have been duly given
or made for all purposes when hand delivered or sent by certified or
registered mail, return receipt requested and postage prepaid, overnight
mail or courier, or telecopier as follows:

      If to Holder at:    Building 6, East Road
                          Rotterdam Industrial Park
                          Schenectady, New York 12306
                          Attention:  David M. Buicko, Executive Vice President
                          Telecopier Number:  (518)356-5334

      With a copy to:     Steven K. Porter, Esquire
                          Rotterdam Industrial Park
                          Westcott Road, Building 6
                          Schenectady, New York 12306
                          Telecopier Number: (518)357-2534

      If to AMNEX at:     145 Huguenot Street
                          New Rochelle, New York 10801
                          Attention:  Chief Financial Officer
                          Telecopier Number:  (914)235-1339

      With a copy to:     Guy A. Longobardo, Esquire
                          145 Huguenot Street
                          New Rochelle, New York 10801

      If to ANEI at:      145 Huguenot Street
                          New Rochelle, New York 10801
                          Attention:  Chief Financial Officer
                          Telecopier Number:  (914)235-1339

      With a copy to:     Guy A. Longobardo, Esquire
                          145 Huguenot Street
                          New Rochelle, New York 10801

or any such other address as the Holder or any Maker may specify by notice
given to the other party in accordance with this paragraph 5.

     6. Miscellaneous. This Note constitutes the rights and obligations of
the Holder and the Makers. No provision of this Note may be modified except
by an instrument in writing signed by the party against whom the enforcement
of any modification is sought.

     Payment of interest due under this Note prior to the Due Date or
Redemption Date, as the case may be, shall be made to the registered holder
of this Note. Payment of principal and interest due hereunder on the Due
Date or Redemption Date, as the case may be, shall be made to the registered
holder of this Note in accordance with the terms hereof following
presentation of this Note upon or after such applicable date. No interest
shall be due on this Note for such period of time that may elapse between
the Due Date or Redemption Date, as the case may be, and its presentation
for payment.

     No recourse shall be had for the payment of the principal of or
interest on this Note against any officer, director or agent of any Maker,
past, present or future, all such liability of the officers, directors and
agents being waived, released and surrendered by the Holder hereof by the
acceptance of this Note.


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     IN WITNESS WHEREOF, the Makers have caused this Note to be signed on
its behalf in its corporate name, by its duly authorized officer, all as of
the day and year first above written.

                                   AMNEX, INC.

                                   By:
                                      --------------------------------------
                                        Name:  Cynthia I. Terrell
                                        Title: Chief Financial Officer


                                   AMERICAN NETWORK EXCHANGE, INC.

                                   By:
                                      --------------------------------------
                                        Name:  Cynthia I. Terrell
                                        Title: Chief Financial Officer