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                                                                     EXHIBIT 4.7
         FILED
  IN THE OFFICE OF THE
SECRETARY OF STATE OF THE
     STATE OF NEVADA

 AUG 19 1998      CERTIFICATE OF DESIGNATION, NUMBER, POWERS,
                    PREFERENCES AND RELATIVE, PARTICIPATING,
No. C3741-84      OPTIONAL, AND OTHER SPECIAL RIGHTS AND THE
    --------      QUALIFICATIONS, LIMITATIONS, RESTRICTIONS,
/s/ Dean Heller  AND OTHER DISTINGUISHING CHARACTERISTICS OF
   DEAN HELLER,            SERIES C PREFERRED STOCK
SECRETARY OF STATE
                                      OF

                       U.S. DIGITAL COMMUNICATIONS, INC.

     The undersigned President and Secretary of U.S. Digital Communications, 
Inc. (the "Corporation") hereby certify that Board of Directors of the 
Corporation, pursuant to the authority expressly vested in it has adopted the 
following resolutions creating a Series C issue of Preferred Stock:

     RESOLVED, that four thousand (4,000) of the ten million (10,000,000) 
authorized shares of Preferred Stock of the Corporation shall be designated 
Series C Preferred Stock (the "Series C Preferred Stock") and shall possess the 
rights and privileges set forth below:

          A.   Par Value, Stated Value, Accretion Rate, Purchase Price and 
               -----------------------------------------------------------
Certificates.
------------
               1.   Each share of Series C Preferred Stock shall have no par 
value and a stated value (face amount) of One Thousand Dollars ($1,000.00) (the 
"Stated Value").

               2.   The Series C Preferred Stock shall be offered at a purchase 
price of One Thousand Dollars ($1,000.00) per share.

               3.   Certificates representing the shares of Series C Preferred 
Stock purchased shall be issued by the Corporation to the purchasers immediately
upon acceptance of the subscriptions to purchase such shares.

          B.   Dividends.
               ---------

               1.   The Series C Preferred Stock will bear no dividends, and the
holders of the Series C Preferred Stock shall not be entitled to the receipt of
dividends on the Series C Preferred Stock.

          C.   Liquidation Preference.
               ----------------------

               1.   In the event of any liquidation, dissolution or winding-up 
of the

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Corporation, either voluntary of involuntary (a "Liquidation"), the holders of
shares of the Series C Preferred Stock then issued and outstanding shall be
entitled to be paid out of the assets of the Corporation available for
distribution to its shareholders, whether from capital, surplus or earnings,
before any payment shall be made to the holders of shares of the Common Stock or
upon any other series of Preferred Stock of the Corporation with a liquidation
preference subordinate to the liquidation preference of the Series A Preferred
Stock and the Series B Preferred Stock, an amount per share equal to the sum of
(i) the Stated Value and (ii) an amount equal to zero percent (0%) of the Stated
Value multiplied by the fraction N/365, where N equals the number of days
elapsed since full payment for the shares of Series C Preferred Stock was
deposited with the escrow agent for the offering of the Series C Preferred
Stock. If, upon any Liquidation of the Corporation, the assets of the
Corporation available for distribution to its shareholders shall be insufficient
to pay the holders of shares of the Series C Preferred Stock and the holders of
any other series of Preferred Stock with a liquidation preference equal to the
liquidation preference of the Series C Preferred Stock the full amounts to which
they shall respectively be entitled, the holders of shares of the Series C
Preferred Stock and the holders of any other series of Preferred Stock with
liquidation preference equal to the liquidation preference of the Series C
Preferred Stock shall receive all of the assets of the Corporation available for
distribution and each such holder of shares of the Series C Preferred Stock and
the holders of any other series of Preferred Stock with a liquidation preference
equal to the liquidation preference of the Series C Preferred Stock shall share
ratably in any distribution in accordance with the amounts due such
shareholders. After payment shall have been made to the holders of shares of the
Series C Preferred Stock of the full amount to which they shall be entitled, as
aforesaid, the holders of shares of the Series C Preferred Stock shall be
entitled to no further distributions thereon and the holders of shares of the
Common Stock and of shares of any other series of stock of the Corporation shall
be entitled to share, according to their respective rights and preferences, in
all remaining assets of the Corporation available for distribution to its
shareholders.

                2. A merger or consolidation of the Corporation with or into any
other corporation, or a sale, lease, exchange, or transfer of all or any part of
the assets of the Corporation which shall not in fact result in the liquidation
(in whole or in part) of the Corporation and the distribution of its assets to
its shareholders shall not be deemed to be a voluntary or involuntary
liquidation (in whole or in part), dissolution, or winding-up of the
Corporation.

     D.  Conversion of Series C Preferred Stock.
         --------------------------------------

         The holders of Series C Preferred Stock shall have the following
conversion rights:

                1. Right to Convert. Fifty percent (50%) of each share of Series
                   ----------------
C Preferred Stock shall be convertible, on the earlier of (i) the effective date
of registration of the underlying Common Stock of the Corporation or (ii) one
hundred and twenty (120) calendar days after the closing of the offering of the
Series C Preferred Stock (the "Closing"), and at the Conversion Prices set forth
below, into fully paid and nonassessable shares of Common Stock, and the
remaining fifty percent (50%) of each share of Series C Preferred Stock all be
convertible on

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the earlier of (x) the forty-fifth (45th) day after the effective date of
registration of the underlying Common Stock of the Corporation, or (y) one
hundred and sixty-five (165) calendar days after Closing, at the Conversion
Prices set forth below (sometimes deferred to herein as "Conversion Shares").

          2. Mechanics of Conversion. Each holder of Series C Preferred
            ------------------------
Stock who desires to convert the same into shares of Common Stock shall provide
notice ("Conversion Notice") via telecopy (facsimile) to the Corporation. The
original Conversion Notice and the certificate or certificates representing the
Series C Preferred Stock for which conversion is elected, shall be delivered to
the Corporation by international courier, duly endorsed. The date upon which a
Conversion Notice is received by the Corporation shall be a "Notice Date."

     Upon receipt by the Corporation of a facsimile copy of a Conversion Notice,
the Corporation shall immediately send to the holder, via telecopy (facsimile),
a confirmation of receipt of the Conversion notice which shall specify that the
Conversion Notice has been received and the name and telephone number of a
contact person at the Corporation whom the holder should contact regarding
information related to the conversion. The Corporation shall use all reasonable
efforts to issue and deliver within three (3) business days after the Notice
Date, to such holder of Series C Preferred Stock at the address of the holder on
the stock books of the Corporation, a certificate or certificates for the number
of shares of Common Stock to which the holder shall be entitled as aforesaid;
provided that the original shares of Series C Preferred Stock to be converted
are received by the transfer agent or the Corporation within three (3) business
days after the Notice Date and the person or persons entitled to receive the
shares of Common Stock issuable upon such conversion shall be treated for all
purposes as the record holder or holders of such shares of Common Stock on such
date. If the original certificate(s) representing the shares of Series C
Preferred Stock to be converted are not received by the transfer agent or the
Corporation within three (3) business days after the Notice Date, the Conversion
Notice shall become null and void.

          3. Lost or Stolen Certificates. Upon receipt by the Corporation of
             ---------------------------
evidence of the loss, destruction, theft or mutilation of any Series C Preferred
Stock certificates (the "Certificates") and (in the case of loss, theft or
destruction) of indemnity or security reasonably satisfactory to the
Corporation, and upon surrender and cancellation of the Certificates, if
mutilated, the Corporation shall execute and deliver new Series C Preferred
Stock Certificates of like tenor and date. However, the Corporation shall not be
obligated to re-issue such lost or stolen Series C Preferred Stock Certificates
if the holder thereof contemporaneously requests the Corporation to convert such
Series C Preferred Stock into Common Stock, in which event the Corporation shall
be entitled to rely on an affidavit of loss, destruction or theft of the Series
C Preferred Stock Certificate or, in the case of mutilation, tender of the
mutilated certificate, and shall issue the Conversion Shares.

          4. Conversion Dates. The shares of Series C Preferred Stock shall
             ----------------
become convertible into shares of Common Stock as stated in Paragraph D.1.
above. Each notice

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upon which a holder elects to convert Series C Preferred Stock shall be 
considered a Conversion Date with respect to such stock and the shares of Common
Stock into which such stock is converted.

               5.   Conversion Formula/Conversion Price.  Each share of Series C
                    -----------------------------------
Preferred Stock shall be convertible into the number of shares of Common Stock
in accordance with the following formula (the "Conversion Formula"):

                      [(.00) x (N/365) x (1,000) + 1,000]
                      -----------------------------------

                               Conversion price

where,

            N=     the number of days between (i) the date that, in connection
                   with the consummation of the initial purchase by holder of
                   shares of Series C Preferred Stock from the Corporation, the
                   escrow agent first had in its possession funds representing
                   full payment for the shares of Series C Preferred Stock being
                   converted, and (ii) the Notice Date.

     Conversion 
     Price =       Discount Price or the Ceiling Price, whichever is less, but 
                   in no event shall the Conversion Price be less than the
                   amount derived by multiplying the Floor Price by 75%.

     Discount
     Price=        25% off of the five (5)-day average Closing Bid Price for the
                   Corporation's Common Stock immediately before Conversion
                   Date.

     Ceiling
     Price=        $3.94 per share.

     Floor Price=  $2.50 per share of the Corporation's Common Stock with the 
                   agreement to adjust the floor should the Corporation's Common
                   Stock trade less than $2.50 per share for five (5)
                   consecutive trading days prior to the conversion dates
                   herein. The adjusted floor shall then be the lowest Closing
                   Bid Price for the Corporation's Common Stock during such five
                   (5)-day period from which the Holder shall be entitled to the
                   Additional Discount.

     For purposes hereof, the term "Closing Bid Price" shall mean the closing 
bid price for the Corporation's Common Stock on the NASD Electronic Bulletin 
Board, or if no longer traded thereon, the closing bid price on the principal 
national securities exchange or quotation system on

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which the Common Stock is so traded. The holder shall be entitled to an 
additional discount privilege equal to one percent (1%) per month or fraction of
a month off the five (5) day average closing bid price for the Corporation's 
Common Stock immediately before the Conversion Date, from the time of Closing 
until the effective date of registration of the underlying Common Stock for any 
conversions thirty (30) days after the effective date of registration of the 
underlying Common Stock and one-half percent (1/2%) per month or fraction of a 
month off the five (5) day average closing bid price for the Corporation's 
Common Stock immediately before the Conversion Date for any conversions 
thereafter ("Additional Discount").

          6.  Automatic Conversion. Each share of Series C Preferred Stock
              --------------------
outstanding on June 1, 2001 automatically shall be converted into Common Stock 
on such date in accordance with the Conversion Formula and the Conversion Price 
then in effect, and June 1, 2001 shall be deemed to be the Notice Date with 
respect to such conversion.

          7.  Forced Conversion. In the event the Floor Price is reached for the
              -----------------
Corporation's Common Stock for five (5) consecutive trading days, the 
Corporation shall have the right, but not the obligation, to require the holders
of Series C Preferred Stock to convert the Series C Preferred Stock into Common 
Stock at such time, at the Conversion Price then in effect, and the date upon 
which the Floor Price has been reached for the Corporations Common Stock for 
five (5) consecutive trading days shall be deemed to be the Notice Date with 
respect to such conversion.

          8.  No Fractional Shares. If any conversion of the Series C Preferred
              --------------------
Stock would create a fractional share of Common Stock or a right to acquire a 
fractional share of Common Stock, such fractional share shall be disregarded and
the number of shares of Common Stock issuable upon conversion, if the aggregate,
shall be the next higher number of shares

          9.  Reservation of Stock Issuable Upon Conversion. The Corporation 
              ---------------------------------------------
shall at all times reserve and keep available out of its authorized but unissued
shares of Common Stock, solely for the purpose of effecting the conversion of
the shares of the Series C Preferred Stock, such number of its shares of Common
Stock as shall from time to time be sufficient to effect the conversion of all
then outstanding shares of the Series C Preferred Stock; and if at any time the
number of authorized but unissued shares of Common Stock shall not be
sufficient to effect the conversion of all then outstanding shares of the Series
C Preferred Stock, the Corporation will take such corporate action as may be
necessary to increase its authorized but unissued shares of Common Stock to such
number of shares as shall be sufficient for such purpose.

         10.  Adjustment to Conversion Price.
              ------------------------------
              
              (a)  If, prior to the conversion of all shares of Series C 
Preferred Stock, the number of outstanding shares of Common Stock is increased 
by a stock split, stock dividend, or other similar event, the Conversion Price 
shall be proportionately reduced, or if the number of outstanding shares of 
Common Stock is decreased by a combination or reclassification 

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of shares, or other similar event, the Conversion Price shall be proportionately
increased.

          (b)  If, prior to the conversion of all shares of Series C Preferred
Stock, there shall be any merger, consolidation, exchange of shares,
recapitalization, reorganization, or other similar event, as a result of which
shares of Common Stock of the Corporation shall be changed into the same or a
different number of shares of the same or another class or classes of stock or
securities of the Corporation or another entity, then the holders of Series C
Preferred Stock shall thereafter have the right to purchase and receive upon
conversion of shares of Series C Preferred Stock, upon the basis and upon the
terms and conditions specified herein and in lieu of the shares of Common Stock
immediately theretofore issuable upon conversion, such shares of stock and/or
securities as may be issued or payable with respect to or in exchange for the
number of shares of Common Stock immediately theretofore purchasable and
receivable upon the conversion of shares of Series C Preferred Stock held by
such holders had such merger, consolidation, exchange of shares,
recapitalization or reorganization not taken place, and in any such case
appropriate provisions shall be made with respect to the rights and interests of
the holders of the Series C Preferred Stock to the end that the provisions
hereof (including, without limitation, provisions for adjustment of the
Conversion Price and of the number of shares issuable upon conversion of the
Series C Preferred Stock) shall thereafter be applicable, as nearly as may be
practicable in relation to any shares of stock or securities thereafter
deliverable upon the exercise hereof. The Corporation shall not effect any
transaction described in this subsection unless the resulting successor or
acquiring entity (if not the Corporation) assumes by written instrument the
obligation to deliver to the holders of the Series C Preferred Stock such shares
of stock and/or securities as, in accordance with the foregoing provisions, the
holders of the Series C Preferred Stock may be entitled to purchase.

          (c)  If any adjustment under this subsection would create a fractional
share of Common Stock or a right to acquire a fractional share of Common Stock,
such fractional share shall be disregarded and the number of shares of Common
Stock issuable upon conversion shall be the next higher number of shares.

     11.  Redemption Privilege.  The Corporation shall have the right, in its
          --------------------
sole discretion, to redeem, prior to receipt of the Notice of Conversion, in
whole or in part any shares of Series C Preferred Stock. The redemption price
shall be the greater of (i) 133% of the Stated Value of the Series C Preferred
Stock or (ii) the amount derived by multiplying (x) the number of shares of the
Corporation's Common Stock into which the Series C Preferred Shares could have
been converted calculated as of the date of the Notice of Conversion, by the
closing asking price of the Corporation's Common Stock as of the date of Notice
of Conversion. The Corporation shall not have a redemption privilege if the
Common Stock is trading above $3.50 per share unless the Holder agrees in
writing to allow the Corporation to redeem such shares.

     E.   Voting.  Except as otherwise provided below or by the General
          ------
Corporation Law of the State of Nevada, the holders of the Series C Preferred
Stock shall have no voting power whatsoever, and no holder of Series C Preferred
Stock shall vote or otherwise participate in any proceeding in which actions
shall be taken by the Corporation or the shareholders

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thereof or be entitled to notification as to any meeting of the Board of 
Directors or the shareholders.

     Notwithstanding the above, Corporation shall provide holders of the Series 
C Preferred Stock ("Holders") with notification of any meeting of the 
shareholders regarding any major corporate events affecting the Corporation. In 
the event of any taking by the Corporation of a record of its shareholders for 
the purpose of determining shareholders who are entitled to receive payment of 
any dividend or other distribution, any right to subscribe for, purchase or 
otherwise acquire any share of any class or any other securities or property 
(including by way of merger, consolidation or reorganization), or to receive any
other right, or for the purpose of determining shareholders who are entitled to 
vote in connection with any proposed sale, lease or conveyance of all or 
substantially all of the assets of the Corporation, or any proposed liquidation,
dissolution or winding up of the Corporation, the Corporation shall mail a 
notice to the Holders, at least ten (10) days prior to the record date specified
therein, of the date on which any such record is to be taken for the purpose of
such dividend, distribution, right or other event, and a brief statement
regarding the amount and character of such dividend, distribution, right or
other event to the extent known at such time.

     To the extent that, under Nevada law, the vote of the Holders, voting 
separately as a class, is required to authorize a given action of the 
Corporation, the affirmative vote or consent of the Holders of at least a 
majority of the shares of the Series C Preferred Stock represented at a duly 
held meeting at which a quorum is present or by written consent of a majority of
the shares of Series C Preferred Stock (except as otherwise may be required 
under Nevada law) shall constitute the approval of such action by the class. To 
the extent that under Nevada law the HOlders are entitled to vote on a matter 
with holders of Common Stock, voting together as one (1) class, each share of 
Series C Preferred Stock shall be entitled to a number of votes equal to the 
number of shares of Common Stock into which it is then convertible using the 
record date for the taking of such vote of stockholders as the date as of which 
the Conversion Price is calculated. The Holders also shall be entitled to notice
of all shareholder meetings or written consents with respect to which they would
be entitled to vote, which notice would be provided pursuant to the
Corporation's by-laws and applicable statutes.

           F.  Protective Provisions. So long as shares of Series C Preferred 
               ---------------------
Stock are outstanding, the Corporation shall not, without first obtaining the 
approval (by vote or written consent, as provided by law) of the Holders of at 
least seventy-five percent (75%) of the then outstanding shares of Series C 
Preferred Stock:

               (a)  alter or change the rights, preferences or privileges of the
Series C Preferred Stock so as to affect adversely the Series C Preferred Stock;

               (b)  create any new class or series of stock or issue any capital
stock senior to or having a preference over or parity with the Series C 
Preferred Stock with respect to dividends, payments upon Liquidation (as 
provided for in Section B of this Designation) or redemption, or increase the 
number of authorized shares of Series C Preferred Stock or change the Stated 
Value thereof;

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<PAGE>
 
               (c)  do any act or thing not authorized or contemplated by this 
Designation which would result in taxation of the holders of shares of the 
Series C Preferred Stock under Section 305 of the Internal Revenue Code of 1986,
as amended (or any comparable provision of the Internal Revenue Code as 
hereafter from time to time amended); or

               (d)  enter into a merger in which the Corporation is not the 
surviving corporation; provided, however, that the provisions of this 
subparagraph (d) shall not be applicable to any such merger if the authorized 
capital stock of the surviving corporation immediately after such merger shall 
include only classes or series of stock for which no such consent or vote would
have been required pursuant to this section if such class or series had been
authorized by the Corporation immediately prior to such merger or which have the
same rights, preferences and limitations and authorized amount as a class or
series of stock of the Corporation authorized (with such consent or vote of the
Series C Preferred Stock) prior to such merger and continuing as an authorized
class or series at the time thereof.

          G.  Status of Converted Stock.  In the event any shares of Series C 
              -------------------------
Preferred Stock shall be converted as contemplated by this Designation, the 
shares so converted shall be canceled, shall return to the status of authorized 
but unissued Preferred Stock of no designated class or series, and shall not be 
issuable by the Corporation as Series C Preferred Stock.

          H.  Taxes.  All shares of Common Stock issued upon conversion of 
              -----
Series C Preferred Stock will be validly issued, fully paid and nonassessable. 
The Corporation shall pay any and all documentary stamp or similar issue or 
transfer taxes that may be payable in respect of any issue or delivery of shares
of Common Stock on conversion of Series C Preferred Stock pursuant hereto. The 
Corporation shall not, however, be required to pay any tax which may be payable 
in respect of any transfer involved in the issue and delivery of shares of 
Common Stock in a name other than that in which the Series C Preferred Stock so 
converted were registered, and no such issue or delivery shall be made unless 
and until the person requesting such transfer has paid to the Corporation the 
amount of any such tax or has established to the satisfaction of the Corporation
that such tax has been paid or that no such tax is payable. The Corporation 
shall adjust the amount of dividends paid or accrued so as to indemnify the 
holders of Preferred Stock against any withholding or similar tax in respect of 
such dividends.

     FURTHER RESOLVED, that the statements contained in the foregoing 
resolutions creating and designating the said Series C Preferred Stock and 
fixing the number, powers, preferences and relative, optional, participating, 
and other special rights and the qualifications, limitations, restrictions, and 
other distinguishing characteristics thereof shall, upon the effective date of 
said series, be deemed to be included in and be a part of the certificate of 
incorporation of the Corporation pursuant to the provisions the General 
Corporation Law of the State of Nevada.

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Signed on August 7, 1998
          --------

                                       US DIGITAL COMMUNICATIONS, INC.

                                       By:    /s/Robert J. Wussler
                                              --------------------

                                       Title: Chairman & CEO
                                              --------------
                                                                                

                                       By:    /s/ [ILLEGIBLE]
                                              ---------------

                                       Title: Secretary
                                              ---------


Attest:

By:
       ------------------

Title:
       ------------------

        [CORPORATE SEAL]

                                                             [Seal]
        
                                                       /s/Ellen M. Gott
                                                        ELLEN M. GOTT
                                               NOTARY PUBLIC STATE OF MARYLAND
                                             My Commission Expires July 21, 2001

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