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                                                                 EXHIBIT NO. 4.2



                           CERTIFICATE OF DESIGNATIONS
                                       OF
                                   AMDL, INC.
                             A DELAWARE CORPORATION


        The undersigned, Gary Dreher and Vivian Frazier, hereby certify that:

        1. They are the duly elected and acting President and Secretary of AMDL,
Inc., a Delaware corporation (the "Corporation").

        2. The Corporation, in its Certificate of Incorporation, has authorized
10,000,000 shares of preferred stock. By resolution, the Board of Directors of
the Corporation has designated 11,000 shares of preferred stock authorized by
the Certificate of Incorporation as "Series A Preferred Stock." No shares of
Preferred Stock have been issued.

        3. Pursuant to authority given by the Corporation's Certificate of
Incorporation, the Board of Directors of the Corporation has duly adopted the
following recital and resolution:

           WHEREAS, Article IV of the Certificate of Incorporation of the
Corporation authorizes this Corporation to issue 10,000,000 shares of preferred
stock, $.001 par value per share, issuable from time to time in one or more
series (the "Preferred Stock").

           RESOLVED, the Board of Directors hereby determines that it is in the
best interests of this Corporation to designate 11,000 shares of the Preferred
Stock as "Series A" upon the following terms and conditions:

        Section 1. Designation. The initial series of Preferred Stock shall be
designated and known as "Series A Preferred Stock." The number of authorized
shares constituting such series shall be 11,000. The Series A Preferred Stock
shall have a par value of $.001 per share.

        Section 2. Definitions. For the purposes of this Certificate of
Designations, the following terms shall have the meanings indicated:

           "Common Stock" shall mean the Corporation's $.001 par value common
stock.

           "Conversion Price" has the meaning assigned to such term in Section
7(a).

           "Initial Conversion Price" shall mean $2.00 per share of Series A
Preferred Stock.

           "Junior Stock" shall mean any capital stock of the Corporation,
including without limitation the Common Stock, ranking junior to the Series A
Preferred Stock with respect to dividends, distribution in liquidation or any
other preferences, rights and powers.

           "Liquidation Preference" shall mean $500 per share of Series A
Preferred Stock.

           "Parity Stock" shall mean any capital stock of the Corporation
ranking on a parity with the Series A Preferred Stock with respect to dividends,
distributions in liquidation and all other preferences, rights or powers.



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           "Person" shall mean any individual, firm, corporation, partnership,
trust, incorporated or unincorporated association, joint venture, joint stock
company, government (or an agency or political subdivision thereof) or other
entity of any kind, and shall include any successor (by merger or otherwise) of
such entity.

           "Public Offering" shall mean any offering of the Common Stock to the
public pursuant to an effective registration statement under the Securities Act
of 1933, as then in effect, or any comparable statement under any similar
federal statute then in force, in which the aggregate gross proceeds shall be at
least $10,000,000.

           "Registration Statement" shall mean a registration statement under
the Securities Act of 1933, as then in effect, or any comparable statement under
any similar federal statute then in force.

           "Senior Stock" shall mean any capital stock of the Corporation
ranking senior to the Series A Preferred Stock with respect to dividends,
distribution in liquidation or any other preference, right or power.

        Section 3. Ranking. The Series A Preferred Stock shall, with respect to
rights on liquidation, dissolution or winding up, rank senior to all other
equity securities of the Corporation, including the Common Stock and any other
series or class of the Corporation's preferred or common stock, now or hereafter
authorized.

        Section 4. Dividends. The holders of shares of Series A Preferred Stock
shall be entitled to receive dividends at the rate of eight percent (8%) per
annum of the Liquidation Preference per share, payable semi-annually
("Dividends"). The Dividends shall commence to accrue on the date of purchase of
such shares of Series A Preferred Stock and shall be payable commencing July 15,
2000 and on January 15 and July 15 of each year thereafter (each a "Dividend
Date"), to holders of record on December 31 and June 30 of each year,
respectively. The Dividends shall be payable in shares of Common Stock at the
rate of one share of Common Stock for the equivalent dollar amount of the
Conversion Price in effect on the applicable Dividend Date. No fractional shares
of Common Stock will be issued in connection with the payment of Dividends. In
lieu of fractional shares of Common Stock, the Corporation shall issue one (1)
additional share of Common Stock to each holder of Series A Preferred Stock
entitled to the portion of the Dividend equal to a fraction of a share of common
stock. The Corporation shall declare and pay the Dividend on a current basis.

        Section 5. Voting Rights.

           (a) The holder of each share of Series A Preferred Stock shall have
the right to one vote for each share of Common Stock into which such holder's
shares of Series A Preferred Stock could then be converted, and with respect to
such vote, such holder shall have full voting rights and powers equal to the
voting rights and powers of the holders of Common Stock, and the holders of
Series A Preferred Stock shall be entitled to notice of any stockholders'
meeting in accordance with the bylaws of the Corporation and shall be entitled
to vote thereon together with the holders of shares of Common Stock.

           (b) Unless the consent or approval of a greater number of shares
shall then be required by law, the affirmative vote of the holders of more than
50% of the outstanding shares of the Series A Preferred Stock shall be necessary
to (i) authorize, increase the authorized number of shares of or issue
(including on conversion or exchange of any convertible or exchangeable
securities or by reclassification) any shares of any class or classes of Senior
Stock or Parity Stock or any additional shares of Series A Preferred Stock, (ii)
authorize, adopt or approve any amendment to the Articles of Incorporation, the
Bylaws or this Certificate of Designations that would increase or decrease the
par value of the shares of the Series A Preferred Stock, alter or change the
powers, preferences or rights of the shares of Series A Preferred Stock or alter
or change the powers, preferences or rights of any other capital stock of the
Corporation if after such alteration or change such capital stock would be
Senior Stock or Parity Stock, (iii) amend, alter or repeal the Articles of
Incorporation or this Certificate of Designations so as to affect the shares of
Series A Preferred Stock adversely, including, without limitation, by granting
any voting right to any holder of notes, bonds, debentures or other debt
obligations of the Corporation, or (iv) authorize or issue any security
convertible into, exchangeable for or evidencing the right to purchase or
otherwise receive any shares of any class or classes of Senior Stock or Parity
Stock.



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        Section 6. Liquidation, Dissolution or Winding Up.

           (a) In the event of any liquidation, dissolution or winding up of the
Corporation, either voluntary or involuntary, before any distribution or payment
to holders of Junior Stock may be made, the holder of each share of Series A
Preferred Stock shall be entitled to be paid an amount equal to the Liquidation
Preference of such share, plus all accrued or declared but unpaid dividends on
such shares of Series A Preferred Stock pro rated for the number of days from
the last Dividend Date to the date of declaration by the Board of Directors of
the winding up of the Corporation.

           (b) If, upon any liquidation, dissolution or winding up of the
Corporation, the assets of the Corporation available for distribution to the
holders of Series A Preferred Stock shall be insufficient to permit payment in
full to such holders of the sums which such holders are entitled to receive in
such case, then all of the assets available for distribution to holders of the
Series A Preferred Stock shall be distributed among and paid to such holders
ratably in proportion to the amounts that would be payable to such holders if
such assets were sufficient to permit payment in full. The consolidation or
merger of the Corporation into or with another corporation or corporations and
the sale of all or substantially all of the assets of the Corporation to another
corporation or any other entity shall be deemed a liquidation, dissolution or
winding up of the Corporation within the meaning of this Section 6.

        Section 7. Conversion of Preferred Stock into Common Stock.

           (a) Right to Convert. The outstanding shares of Series A Preferred
Stock shall be convertible, at any time at the option of the holders thereof,
subject to the restrictions set forth in Section 7(c), into fully paid and
nonassessable shares of Common Stock at the Initial Conversion Price, subject to
adjustment as set forth in this Section 7 (the "Conversion Price").

           (b) Number of shares of Common Stock Issuable upon Conversion. The
number of shares of Common Stock to be issued upon conversion of shares of
Series A Preferred Stock shall be equal to the product of (X) and (Y), where (X)
is a fraction, the numerator of which is the Liquidation Preference and the
denominator of which is the applicable Conversion Price and (Y) is the number of
shares of Series A Preferred Stock to be converted.

           (c) Automatic Conversion. The outstanding shares of Series A
Preferred Stock shall be automatically converted into shares of Common Stock at
the Conversion Price at such time as (i) the Common Stock is listed for trading
on the Nasdaq Small Cap Market or Nasdaq National Market System and (ii) a
Registration Statement covering the Common Stock issuable upon conversion of the
Series A Preferred Stock has been declared effective by the Securities and
Exchange Commission ("SEC").

           (d) Restrictions on Conversion. Notwithstanding the provisions of
Section 7(a) above, in the event of a Public Offering, shares of Series A
Preferred Stock may not be converted into shares of Common Stock during the
period of time commencing on the date the Corporation files a Registration
Statement with the SEC covering the Common Stock until the date which is the
earlier of (i) 270 days following the filing of the Registration Statement with
the SEC, or (ii) 180 days following the closing of the Public Offering.

           (e) Antidilution Adjustments. The Conversion Price of the Series A
Preferred Stock shall be adjusted from time to time in certain cases as follows:

               (i) Dividend, Subdivision, Combination or Reclassification of
Common Stock. If the Corporation shall, at any time or from time to time, (A)
declare a dividend on the Common Stock payable in shares of its capital stock
(including Common Stock), (B) subdivide the outstanding Common Stock, (C)
combine the outstanding Common Stock into a smaller number of shares, or (D)
issue any shares of its capital stock in a reclassification of the Common Stock
(including any such reclassification in connection with a consolidation or
merger in which the Corporation is the continuing corporation), then in each
such case, the Initial Conversion Price or the Conversion Price in effect at the
time of the record date for such dividend or at the effective date of such



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subdivision, combination or reclassification shall be adjusted to that price
which will permit the number of shares of Common Stock into which the Series A
Preferred Stock may be converted to be increased or reduced in the same
proportion as the number of shares of Common Stock are increased or reduced in
connection with such dividend, subdivision, combination or reclassification. Any
such adjustment shall become effective immediately after the record date of such
dividend or the effective date of such subdivision, combination or
reclassification. Such adjustment shall be made successively whenever any event
listed above shall occur. In the event, if a dividend is declared, such dividend
is not paid, the Conversion Price shall be adjusted to the Conversion Price in
effect immediately prior to the record date of such dividend.

               (ii) De Minimis Adjustments. No adjustment of the Conversion
Price shall be made if the amount of such adjustment would result in a change in
the Conversion Price per share of less than $.05 but in such case any adjustment
that would otherwise be required then to be made shall be carried forward and
shall be made at the time of and together with the next subsequent adjustment,
which together with any adjustment so carried forward, would result in a change
in the Conversion Price in excess of $.05 per share. All calculations under this
Section 7(e) shall be made to the nearest cent, or the nearest 1/100th of a
share, as the case may be. If the Corporation shall, at any time or from time to
time, issue Common Stock by way of dividends on any stock of the Corporation or
subdivide or combine the outstanding shares of the Common Stock, such amount of
$.05 (as theretofore increased or decreased, if such amount shall have been
adjusted in accordance with the provisions of this clause) shall forthwith be
proportionately increased in the case of a combination or decreased in the case
of a subdivision or stock dividend so as appropriately to reflect the same.
Notwithstanding the provisions of the first sentence of this Section 7(e)(iii),
any adjustment postponed pursuant to this Section 7(e)(ii) shall be made no
later than the earlier of (a) two years from the date of the transaction that
would, but for the provisions of the first sentence of this Section 7(e)(ii),
have required such adjustment and (b) the date of any redemption or conversion
of the shares of Series A Preferred Stock.

               (iii) Fractional Shares. Notwithstanding any other provision of
this Certificate of Designations, the Corporation shall not be required to issue
fractions of shares upon conversion of any shares of Series A Preferred Stock or
to distribute certificates which evidence fractional shares. In lieu of
fractional shares of Common Stock, the Corporation shall pay therefore, at the
time of any conversion of shares of Series A Preferred Stock as herein provided,
an amount in cash equal to such fraction multiplied by the Conversion Price then
in effect.

           (f) Reorganization and Reclassification Adjustment. If there occurs
any capital reorganization or any reclassification of the Common Stock of the
Corporation, then each share of Series A Preferred Stock shall thereafter be
convertible into the same kind and amounts of securities (including shares of
stock) or other assets, or both, which were issuable or distributable to the
holders of outstanding Common Stock of the Corporation upon such reorganization
or reclassification in respect of that number of shares of Common Stock into
which such shares of Series A Preferred Stock might have been converted
immediately prior to such reorganization or reclassification; and, in any such
case, appropriate adjustments (as determined in good faith by the Board of
Directors of the Corporation) shall be made to assure that the provisions set
forth herein (including provisions with respect to changes in, and other
adjustments of, the Conversion Price) shall thereafter be applicable, as nearly
as reasonably may be practicable, in relation to any securities or other assets
thereafter deliverable upon the conversion of the Series A Preferred Stock.

           (g) Mechanics of Conversion. The option to convert shall be exercised
by surrendering for such purpose to the Corporation, certificates representing
the shares to be converted, duly endorsed in blank or accompanied by proper
instruments of transfer, and at the time of such surrender, the Person in whose
name any certificate for shares of Common Stock shall be issuable upon such
conversion shall be deemed to be the holder of record of such shares of Common
Stock on such date, notwithstanding that the share register of the Corporation
shall then be closed or that the certificates representing such Common Stock
shall not then be actually delivered to such person.

           (h) Certificate as to Adjustments. Whenever the Conversion Price or
the securities or other property deliverable upon the conversion of the Series A
Preferred Stock shall be adjusted pursuant to the provisions hereof, the
Corporation shall promptly give written notice thereof to each holder of shares
of Series A



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Preferred Stock at such holder's address as it appears on the transfer books of
the Corporation and shall forthwith file, at its principal executive office and
with any transfer agent or agents for the shares of Series A Preferred Stock and
the Common Stock, a certificate, signed by the Chairman of the Board, Chief
Executive Officer or one of the Vice Presidents of the Corporation, and by its
Chief Financial Officer, its Treasurer or one of its Assistant Treasurers,
stating the adjusted Conversion Price and the securities or other property
deliverable per share of Series A Preferred Stock calculated to the nearest cent
or to the nearest one one-hundredth of a share and setting forth in reasonable
detail the method of calculation and the facts requiring such adjustment and
upon which such calculation is based. Each adjustment shall remain in effect
until a subsequent adjustment hereunder is required.

           (i) Reservation of Common Stock. The Corporation shall at all times
reserve and keep available for issuance upon the conversion of the shares of
Series A Preferred Stock, the maximum number of its authorized but unissued
shares of Common Stock as is reasonably anticipated to be sufficient to permit
the conversion of all outstanding shares of Series A Preferred Stock, and shall
take all action required to increase the authorized number of shares of Common
Stock if at any time there shall be insufficient authorized but unissued shares
of Common Stock to permit such reservation or to permit the conversion of all
outstanding shares of Series A Preferred Stock.

           (j) No Conversion Charge or Tax. The issuance and delivery of
certificates for shares of Common Stock upon the conversion of shares of Series
A Preferred Stock shall be made without charge to the holder of shares of Series
A Preferred Stock for any issue or transfer tax, or other incidental expense in
respect of the issuance or delivery of such certificates or the securities
represented thereby, all of which taxes and expenses shall be paid by the
Corporation.

        Section 8. No Redemption of Series A Preferred Stock. The Corporation
shall not have the right to redeem the Series A Preferred Stock.

        Section 9. Notice of Certain Events. In case the Corporation shall
propose at any time or from time to time (A) to declare or pay any dividend
payable in stock of any class to the holders of Common Stock or to make any
other distribution to the holders of Common Stock, (B) to offer to the holders
of Common Stock rights or warrants to subscribe for or to purchase any
additional shares of Common Stock or shares of stock of any class or any other
securities, rights or options, (C) to effect any reclassification of its Common
Stock, (D) to effect any consolidation, merger or sale, transfer or other
disposition of all or substantially all of the property, assets or business of
the Corporation which would, if consummated result in the mandatory conversion
of shares of Series A Preferred Stock, or (E) to effect the liquidation,
dissolution or winding up of the Corporation, then, in each such case, the
Corporation shall mail to each holder of shares of Series A Preferred Stock via
first class mail at such holder's address as it appears on the transfer books of
the Corporation, a written notice of such proposed action, which shall specify
(1) the date on which a record is to be taken for the purpose of such dividend,
distribution or rights or warrants or, if a record is not to be taken, the date
as of which the holders of shares of Common Stock of record to be entitled to
such dividend, distribution or rights are to be determined, or (2) the date on
which such reclassification, consolidation, merger, sale, conveyance,
dissolution, liquidation or winding up is expected to become effective, and such
notice shall be so given as promptly as possible but in any event at least ten
(10) business days prior to the applicable record, determination or effective
date, specified in such notice.

        Section 10. Certain Remedies. Any registered holder of shares of Series
A Preferred Stock shall be entitled to an injunction or injunctions to prevent
breaches of the provisions of this Certificate of Designations and to enforce
specifically the terms and provisions of this Certificate of Designations in any
court of the United States or any state thereof having jurisdiction, this being
in addition to any other remedy to which such holder may be entitled at law or
in equity.

        Section 11. Method of Election. For purposes of this Certificate of
Designations, any election required or allowed to be made by the majority of the
holders of Series A Preferred Stock shall be effective upon receipt by the
Corporation of the written consent of a majority of such holders.



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        Section 12. Status of Reacquired Shares. Shares of Series A Preferred
Stock which have been issued and converted shall (upon compliance with any
applicable provisions of the laws of the State of Delaware) have the status of
authorized and unissued shares of Preferred Stock issuable in series
undesignated as to series and may be redesignated and reissued.

        The undersigned President and Secretary of AMDL, Inc. hereby declare and
certify under penalty of perjury that the foregoing Certificate is the act and
deed of the Corporation and that the facts herein stated are true.

        Executed at Tustin, California on December ___, 1999.



                                        ________________________________________
                                        GARY L. DREHER President



                                        ________________________________________
                                        VIVIAN FRAZIER, Secretary



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