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                                   EXHIBIT 4.5

        THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
        1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE AND MAY NOT BE
        SOLD OR OFFERED FOR SALE IN THE ABSENCE OF AN EFFECTIVE REGISTRATION
        STATEMENT FOR THE SECURITIES OR AN OPINION OF COUNSEL OR OTHER EVIDENCE
        ACCEPTABLE TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED.

No.     06-01-1                                                 US $1,620,000.00
        ----------------
                               AMBIENT CORPORATION

                    SECURED PROMISSORY NOTE DUE JUNE 24, 2006

        THIS NOTE is one of a duly authorized issue of up to $1,620,000 of
AMBIENT CORPORATION, a corporation organized and existing under the laws of the
State of Delaware (the "Company"), designated as its Secured Promissory Note
Series 06-01.

        FOR VALUE RECEIVED, the Company promises to pay to DOUBLE U MASTER FUND
L.P., the registered holder hereof (the "Holder"), the principal sum of One
Million Six Hundred Twenty Thousand and 00/100 Dollars (US $1,620,000.00) on the
Maturity Date (as defined below).

        TIME IS OF THE ESSENCE WITH RESPECT TO THE COMPANY'S FULFILLMENT OF ALL
OF ITS PAYMENT OBLIGATIONS HEREUNDER. The Holder shall not be required to give
the Company any notice of default of payment if any such payment is not timely
paid or otherwise satisfied. All provisions of this Note which apply in the
event of the Company's not timely fulfilling any of its payment obligations
hereunder shall apply whether or not such notice of default is given. The
Holder's giving of any notice to the Company shall not be deemed a waiver,
modification or amendment of this provision with respect to the failure referred
to in that notice or to any other failure by the Company timely to make any
other payment due hereunder.

        This Note or its predecessor was originally issued on January __, 2006
(the "Issue Date").

        This Note is being issued pursuant to the terms of the Bridge Loan
Agreement, dated as of January 18, 2006 (the "Bridge Loan Agreement"), to which
the Company and the Holder (or the Holder's predecessor in interest) are
parties. Capitalized terms not otherwise defined herein shall have the meanings
ascribed to them in the Bridge Loan Agreement.

        This Note is subject to the following additional provisions:

        1.      The Note will initially be issued in denominations determined by
the Company, but are exchangeable for an equal aggregate principal amount of
Note of different denominations, as requested by the Holder surrendering the
same. No service charge will be made for such registration or transfer or
exchange.

        2.      No interest will accrue on this Note until the Maturity Date. If
any portion of this Note is outstanding on the Maturity Date, interest at the
rate of fourteen percent (14%) per annum or the highest rate allowed by law,
whichever is lower, shall accrue on the outstanding principal of this Note from
the Maturity Date to and including the date of payment by the Company. Such
interest shall accrue on a daily basis and shall be payable in cash. The Holder
may demand payment of all or any part of this Note, together with accrued
interest, if any, and any other amounts due hereunder, as of the Maturity Date
or any date thereafter.

        3.      The Company shall be entitled to withhold from all payments of
principal of, and, if applicable, interest on, this Note any amounts required to
be withheld under the applicable provisions of the United States income tax laws
or other applicable laws at the time of such payments, and Holder shall execute
and deliver all required documentation in connection therewith.

        4.      This Note has been issued subject to investment representations
of the original purchaser hereof and may be transferred or exchanged only in
compliance with the Securities Act of 1933, as amended (the "Act"),

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and other
applicable state and foreign securities laws and the terms of the Bridge Loan
Agreement. In the event of any proposed transfer of this Note, the Company may
require, prior to issuance of a new Note in the name of such other person, that
it receive reasonable transfer documentation that is sufficient to evidence that
such proposed transfer complies with the Act and other applicable state and
foreign securities laws and the terms of the Bridge Loan Agreement. Prior to due
presentment for transfer of this Note, the Company and any agent of the Company
may treat the person in whose name this Note is duly registered on the Company's
Note Register as the owner hereof for the purpose of receiving payment as herein
provided and for all other purposes, whether or not this Note be overdue, and
neither the Company nor any such agent shall be affected by notice to the
contrary.

        5       (a)     The term "Maturity Date" means the earliest of (i) June
___, 2006 (the "Stated Maturity Date"), (ii) the New Transaction Threshold Date
(as defined below), or (iii) the Default Maturity Date (as defined below).

                (b)     The term "New Transaction Threshold Date" means the date
on which the Company consummates the first New Transaction in which the Company
receives, on a cumulative basis after taking into account the gross proceeds
from all prior New Transactions, if any, after the Issue Date, gross proceeds of
at least Two Million Dollars ($2,000,000). All such gross proceeds are
determined before deduction of any fees or other expenses or disbursements of
any kind in connection with the relevant New Transaction.

        6.      (a)     Any payment made on account of this Note shall be
applied in the following order of priority: (i) first, to any amounts due
hereunder other than principal and accrued interest, (ii) then, to accrued
interest, if any, through and including the date of payment, and (iii) then, to
principal of this Note.

                (b)     Subject to the provisions of Section 6(a) hereof, the
outstanding principal of this Note may be prepaid in whole or in part at the
option of the Company at any time prior to the Maturity Date.

        7.      All payments contemplated hereby are to be made "in cash" and
shall be made in immediately available good funds of United States of America
currency by wire transfer to an account designated in writing by the Holder to
the Company (which account may be changed by notice similarly given). For
purposes of this Note, the phrase "date of payment" means the date good funds
are received in the account designated by the notice which is then currently
effective.

        8.      (a)     Subject to the terms of the Bridge Loan Agreement, no
provision of this Note shall alter or impair the obligation of the Company,
which is absolute and unconditional, to pay the principal of, and, if
applicable, interest on, this Note at the time, place, and rate, and in the coin
or currency, as herein prescribed. This Note is a direct obligation of the
Company.

                (b)     Payment of this Note is secured pursuant to the terms of
the Security Interest Agreement, dated as of January 18, 2006 (the "Security
Interest Agreement"), executed by the Company, as debtor, in favor of the
Lender, as secured party. The terms of the Security Interest Agreement are
incorporated herein by reference.

        9.      No recourse shall be had for the payment of the principal of,
or, if applicable, the interest on, this Note, or for any claim based hereon, or
otherwise in respect hereof, against any incorporator, shareholder, officer or
director, as such, past, present or future, of the Company or any successor
corporation, whether by virtue of any constitution, statute or rule of law, or
by the enforcement of any assessment or penalty or otherwise, all such liability
being, by the acceptance hereof and as part of the consideration for the issue
hereof, expressly waived and released.

        10.     The Holder of the Note, by acceptance hereof, agrees that this
Note is being acquired for investment and that such Holder will not offer, sell
or otherwise dispose of this Note except under circumstances which will not
result in a violation of the Act or any applicable state Blue Sky or foreign
laws or similar laws relating to the sale of securities.

        11.     Any notice required or permitted hereunder shall be given in
manner provided in the Section headed "NOTICES" in the Bridge Loan Agreement,
the terms of which are incorporated herein by reference.

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        12.     (a)     This Note shall be governed by and interpreted in
accordance with the laws of the State of Delaware for contracts to be wholly
performed in such state and without giving effect to the principles thereof
regarding the conflict of laws. Each of the parties consents to the exclusive
jurisdiction of the federal courts whose districts encompass any part of the
City of Wilmington or the state courts of the State of Delaware sitting in the
City of Wilmington in connection with any dispute arising under this Note and
hereby waives, to the maximum extent permitted by law, any objection, including
any objection based on FORUM NON CONVENIENS, to the bringing of any such
proceeding in such jurisdictions. To the extent determined by such court, the
Company shall reimburse the Holder for any reasonable legal fees and
disbursements incurred by the Holder in enforcement of or protection of any of
its rights under this Note.

                (b)     JURY TRIAL WAIVER. The Company and the Holder hereby
waive a trial by jury in any action, proceeding or counterclaim brought by
either of the Parties hereto against the other in respect of any matter arising
out of or in connection with this Note.

        13.     (a)     The following shall constitute an "Event of Default":

                                i.      The Company shall default in the timely
                        payment of principal on this Note or any other amount
                        due hereunder (without the requirement of any further
                        notice with respect thereto from the Holder); or

                                ii.     Any of the representations or warranties
                        made by the Company herein, in the Bridge Loan Agreement
                        or any of the other Transaction Agreements shall be
                        false or misleading in any material respect at the time
                        made; or

                                iii.    The Company shall fail to perform or
                        observe, in any material respect, any other covenant,
                        term, provision, condition, agreement or obligation of
                        any Note in this series and such failure shall continue
                        uncured for a period of thirty (30) days after the
                        Company's receipt of written notice thereof from the
                        Holder; or

                                iv.     The Company shall fail to perform or
                        observe, in any material respect, any covenant, term,
                        provision, condition, agreement or obligation of the
                        Company under any of the Transaction Agreements and such
                        failure shall continue uncured for a period of thirty
                        (30) days after the Company's receipt of written notice
                        thereof from the Holder; or

                                v.      The Company shall (1) admit in writing
                        its inability to pay its debts generally as they mature;
                        (2) make an assignment for the benefit of creditors or
                        commence proceedings for its dissolution; or (3) apply
                        for or consent to the appointment of a trustee,
                        liquidator or receiver for its or for a substantial part
                        of its property or business; or

                                vi.     A trustee, liquidator or receiver shall
                        be appointed for the Company or for a substantial part
                        of its property or business without its consent and
                        shall not be discharged within sixty (60) days after
                        such appointment; or

                                vii.    Any governmental agency or any court of
                        competent jurisdiction at the instance of any
                        governmental agency shall assume custody or control of
                        the whole or any substantial portion of the properties
                        or assets of the Company and shall not be dismissed
                        within sixty (60) days thereafter; or viii. Any money
                        judgment, writ or warrant of attachment, or similar
                        process in excess of Seven Hundred Fifty Thousand
                        ($750,000) Dollars in the aggregate shall be entered or
                        filed against the Company or any of its properties or
                        other assets and shall remain unpaid, unvacated,
                        unbonded or unstayed for a period of sixty (60) days or
                        in any event later than five (5) days prior to the date
                        of any proposed sale thereunder; or

                                ix.     Bankruptcy, reorganization, insolvency
                        or liquidation proceedings or other proceedings for
                        relief under any bankruptcy law or any law for the
                        relief of debtors

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                        shall be instituted by or against the Company and, if
                        instituted against the Company, shall not be dismissed
                        within sixty (60) days after such institution or the
                        Company shall by any action or answer approve of,
                        consent to, or acquiesce in any such proceedings or
                        admit the material allegations of, or default in
                        answering a petition filed in any such proceeding.

                (b)     If an Event of Default shall have occurred and is
continuing, then, or at any time thereafter, and in each and every such case,
unless such Event of Default shall have been cured or waived in writing by the
Holder (which waiver shall not be deemed to be a waiver of any subsequent
default), at the option of the Holder and in the Holder's sole discretion, the
Holder may consider this Note immediately due and payable (and the Maturity Date
shall be accelerated accordingly; the "Default Maturity Date"), without
presentment, demand, protest or notice of any kinds, all of which are hereby
expressly waived, anything herein or in any note or other instruments contained
to the contrary notwithstanding, and the Holder may immediately enforce any and
all of the Holder's rights and remedies provided herein or any other rights or
remedies afforded by law, including, but not necessarily limited to, the
equitable remedy of specific performance and injunctive relief.

        14.     In the event for any reason, any payment by or act of the
Company or the Holder shall result in payment of interest which would exceed the
limit authorized by or be in violation of the law of the jurisdiction applicable
to this Note, then IPSO FACTO the obligation of the Company to pay interest or
perform such act or requirement shall be reduced to the limit authorized under
such law, so that in no event shall the Company be obligated to pay any such
interest, perform any such act or be bound by any requirement which would result
in the payment of interest in excess of the limit so authorized. In the event
any payment by or act of the Company shall result in the extraction of a rate of
interest in excess of a sum which is lawfully collectible as interest, then such
amount (to the extent of such excess not returned to the Company) shall, without
further agreement or notice between or by the Company or the Holder, be deemed
applied to the payment of principal, if any, hereunder immediately upon receipt
of such excess funds by the Holder, with the same force and effect as though the
Company had specifically designated such sums to be so applied to principal and
the Holder had agreed to accept such sums as an interest-free prepayment of this
Note. If any part of such excess remains after the principal has been paid in
full, whether by the provisions of the preceding sentences of this Section or
otherwise, such excess shall be deemed to be an interest-free loan from the
Company to the Holder, which loan shall be payable immediately upon demand by
the Company. The provisions of this Section shall control every other provision
of this Note.

        IN WITNESS WHEREOF, the Company has caused this instrument to be duly
executed by an officer thereunto duly authorized.

Dated:  January , 2006

                               AMBIENT CORPORATION

        By:/s/ John J. Joyce

        John J. Joyce
        (Print Name)

        President and Chief Executive Officer
        (Title)