Exhibit 10.18
                                 -------------


                                                                  Execution Copy

THE SECURITIES  REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933,  AS  AMENDED,  OR ANY  STATE  SECURITIES  LAWS  (COLLECTIVELY,  THE
"ACTS"),  AND MAY NOT BE  OFFERED,  SOLD OR  OTHERWISE  TRANSFERRED,  PLEDGED OR
HYPOTHECATED  UNLESS AND UNTIL REGISTERED UNDER ALL APPLICABLE ACTS OR UNLESS AN
OPINION OF COUNSEL IS DELIVERED TO THE ISSUER IN FORM AND SUBSTANCE SATISFACTORY
TO THE ISSUER TO THE EFFECT THAT AN EXEMPTION FROM REGISTRATION IS AVAILABLE.

                   SENIOR SECURED CONVERTIBLE PROMISSORY NOTE
                   ------------------------------------------

U.S. $250,000                                                   February 1, 2006


         FOR  VALUE  RECEIVED,   RemoteMDX,   Inc.,  a  Utah   corporation  (the
"Company"), hereby promises to pay to the order of Clydesdale Partners, LLC (the
"Lender"),  or its  successors  or assigns,  subject to this  Note's  conversion
pursuant to Section 1, on the earlier to occur of (a) February 28, 2006, (b) the
initial closing of the Company's  contemplated sale (a "Contemplated Sale") of a
class of stock to be designated as Series C Convertible  Preferred Stock, $.0001
par value per share ("Series C Preferred"),  or (c) an Event of Acceleration (as
hereinafter  defined)  (the  "Maturity  Date"),  the  principal  amount  of U.S.
$250,000 (the "Principal Amount"), together with any accrued and unpaid interest
on the Principal Amount under this convertible  promissory note (this "Note") at
the per annum rate of 8% (calculated on the basis of a 365 day year), compounded
weekly,  for the period  beginning on the date hereof and  continuing  until the
Principal  Amount  shall have  become due and  payable or this Note  having been
converted in full.

         Except as  otherwise  expressly  provided  in  Section  3  hereof,  all
payments of principal  and interest on this Note shall be in cash,  in such coin
or currency of the United  States of America as at the time of payment  shall be
legal tender for payment of public and private debts.  Payments of principal and
interest are to be made by wire transfer to the account designated in writing by
the Lender and provided to the Company not less than three  business  days prior
to the date  payment  is due or at such  other  place as the  Lender  shall have
notified the Company in writing at least three business days before such payment
is due.  All  payments  under  this Note  shall be paid by the  Company  without
withholding or deduction of any tax or other charge.  For purposes of this Note,
a  business  day shall be any day other  than a  Saturday,  Sunday or any day in
which the banking and commercial  lending  institutions  are generally closed to
the public. Interest on this Note shall be paid within 5 days of the end of each
calendar month until the Maturity Date.

         1. Conversion.

              1.1 Optional Conversion.

                     (a) The outstanding  Principal Amount under this Note, plus
any accrued but unpaid  interest  thereon  shall be  convertible  in whole or in
part,  at Lender's sole option,  into shares of Series C Preferred  Stock in the
Contemplated  Sale, at a conversion price equal to the price per share of Series
C  Preferred  Stock  sold in the  Contemplated  Sale (the  "Conversion  Price"),
subject to adjustment in accordance with Section 4 hereof.

                     (b) The Company  covenants  and agrees that so long as this
Note is outstanding and the  Contemplated  Sale has occurred,  the Company shall
have authorized and reserved a sufficient number of shares of Series C Preferred
Stock to enable the Lender to convert  this Note into Series C Preferred  Stock.
The  Company  agrees  that its  issuance  of this  Note  shall  constitute  full

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authority  to its  officers  who are charged  with the duty of  executing  stock
certificates to execute and issue the necessary certificates for shares upon the
conversion of this Note.

              1.2 Procedure.  Subject to the terms hereof, the Lender may effect
the  conversion  of this Note, in whole or in part, at any time, or from time to
time,  by the  surrender  of this  Note,  together  with an  executed  notice of
conversion  (the "Notice of  Conversion") in the form attached hereto as Exhibit
A, to the Company at it usual address.  The person in whose name any certificate
representing shares or securities shall be issuable upon conversion of this Note
shall be deemed to have become the holder of record of, and shall be treated for
all  purposes  as the  record  holder  of,  the  shares or  securities  issuable
hereunder  (and such shares or  securities  shall be deemed to have been issued)
immediately  prior to the close of business on the date or dates upon which such
surrender is made.  In the event only a portion of this Note is  converted,  the
Company  shall at its sole  expense  and as  promptly  as  practicable,  issue a
replacement  Note in  identical  form  but in a  Principal  Amount  equal to the
portion of the Principal  Amount not so converted  and deliver such  replacement
Note as directed by the Lender.  As used in this Note,  the term "person"  means
any individual or any corporation, partnership, trust, limited liability company
or other entity or organization of any kind.

         2. Optional Prepayment.  The Company shall have the right to prepay the
Principal  Amount and any accrued  interest  thereon in whole without penalty or
premium at any time. Upon any notice of prepayment, Lender shall have the option
to convert all but not less than all of the  Principal  Amount then  outstanding
under this Note,  plus any  accrued  but unpaid  interest  thereon,  pursuant to
Section 1. Any  prepayment  amount  shall be applied  first to any  accrued  but
unpaid  interest on the outstanding  Principal  Amount and then to the Principal
Amount.

         3. Events of Acceleration.

         The entire unpaid  Principal  Amount and accrued interest thereon shall
become  immediately  due and payable upon the  occurrence  of one or more of the
following events (each an "Event of Acceleration"):

                     (a)  the  failure  of the  Company  to  pay  when  due  any
Principal  Amount or interest  accrued thereon within five days of the date such
payment is due;

                     (b) the Company  materially  breaches any representation or
warranty  contained in this Note,  or fails to comply in any  material  respect,
with any of the terms or covenants of the Note or any other  agreements  entered
into by the Company in connection with the Note;

                     (c) the  Company  (i)  fails to make any  payment  when due
under the terms of any bond,  debenture,  note or other evidence of indebtedness
or (ii) defaults in the observance or performance of any other  agreement,  term
or condition  contained in any such bond,  debenture,  note or other evidence of
indebtedness or other material agreement of the Company; provided, however, that
the fact that the Company has not yet filed one or more registration  statements
with the SEC pursuant to its commitments to certain investors under the terms of
registration  rights agreements  disclosed or made reference to in the Company's
Current  Reports on Forms 8-K filed with the SEC on November 2 and  November 23,
2005, shall not constitute an Event of Acceleration hereunder.

                     (d) the beginning of  involuntary  proceedings  against the
Company under federal  bankruptcy law or under any  applicable  federal or state
bankruptcy,  insolvency, or similar law, or the beginning of proceedings seeking
the  appointment  of  a  receiver,  liquidator,  assignee,  custodian,  trustee,

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<PAGE>

sequestrator (or similar official) of the Company or for any substantial part of
the Company's property, or the beginning of proceedings seeking an order winding
up or  liquidating  the  affairs  of the  Company  and the  continuance  of such
proceedings for a period of thirty (30) days;

                     (e) the beginning by the Company of a voluntary  case under
federal  bankruptcy law, or any other  applicable  federal or state  bankruptcy,
insolvency,  or  other  similar  law,  or  the  consent  by the  Company  to the
appointment  of, or taking  possession  by, a  receiver,  liquidator,  assignee,
trustee,  custodian,  sequestrator (or other similar official) of the Company or
for any substantial  part of the Company's  property,  or the Company making any
assignment for the benefit of creditors, or the failure of the Company generally
to pay the Company's debts as they become due, or the taking of formal action by
the Company in furtherance of any of the foregoing;

                     (f) if any judgment against the Company or any garnishment,
attachment  or other levy  against the  property of the Company for an amount in
excess of Fifty  Thousand  Dollars  ($50,000) in the aggregate  remains  unpaid,
unstayed  on appeal,  undischarged,  unbonded,  or  undismissed  for a period of
thirty (30) days, unless covered by insurance;

         The Company shall give the Lender  written  notice of the occurrence of
any of the events set forth above in Sections 3(a) through 3(h) promptly (but in
no event more than one business day) after the occurrence of any of such events.

         Upon the occurrence of any Event of Acceleration,  interest shall begin
to accrue on any unpaid Principal Amount and accrued interest at the rate of 15%
per annum (or such lesser amount as may not be  prohibited  by applicable  law),
compounded daily.

         4. Certain Adjustments. The Conversion Price and the number and type of
shares  into which this Note may be  converted  under  Section  1.1(a)  shall be
subject to adjustment in accordance with the following provisions:

              4.1 Adjustments  for Split,  Subdivision or Combination of Shares.
In the event the outstanding shares of Series C Preferred Stock or Common Stock,
$.0001  par value per  share  ("Common  Stock")  shall be  subdivided  (by stock
dividend, stock split, or otherwise),  into a greater number of shares of Series
C Preferred  Stock or Common Stock,  the Conversion  Price then in effect shall,
concurrently  with the  effectiveness of such  subdivision,  be  proportionately
decreased.  In the event the  outstanding  shares of Series C Preferred Stock or
Common  Stock  shall  be  combined  or  consolidated,   by  reclassification  or
otherwise,  into a lesser number of shares of Series C Preferred Stock or Common
Stock,  the  Conversion  Price  then in  effect  shall,  concurrently  with  the
effectiveness  of  such  combination  or   consolidation,   be   proportionately
increased.

              4.2 Adjustments for Distributions. In the event the Company at any
time or from time to time makes, or fixes a record date for the determination of
holders of Series C Preferred  Stock or Common  Stock  entitled to receive,  any
distribution,  provision  shall be made so that the Lender  shall  receive  upon
conversion  of the Note under  Section 1, in addition to the number of shares of
Series C Preferred  Stock  receivable  thereupon,  the amount of  securities  or
assets of the Company  which the Lender  would have  received  had the Note been
converted into Series C Preferred Stock on the date of such event under Sections
1, and had the Lender thereafter,  during the period from the date of such event
to and including  the date of  conversion,  retained  such  securities or assets
receivable  by  it as  aforesaid  during  such  period,  subject  to  all  other
adjustments  called for during such period  under this Section 4 with respect to
the rights of the Lender.

              4.3 Adjustments for  Reclassification,  Exchange and Substitution.
If the Series C  Preferred  Stock  issuable  upon  conversion  of the Note under
Sections 1 shall be changed into the same or a different number of shares of any

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other class or classes of stock or other  securities or property of the Company,
whether by capital  reorganization,  reclassification or otherwise (other than a
subdivision or combination of shares  provided for in Section 4.1),  then and in
each such event provision  shall be made so that the Lender shall  thereafter be
entitled to receive, upon conversion of the Note under Sections 1, the number of
shares of stock or other  securities  or property  of the Company or  otherwise,
receivable upon such reorganization,  reclassification or other transaction by a
holder of the number of shares of Series C Preferred  Stock into which this Note
could  have  been  converted  under  Sections  1,  immediately   prior  to  such
reorganization,  reclassification  or  other  transaction.  In  any  such  case,
appropriate  adjustment  shall be made in the  application  of the provisions of
this   Section  4  with   respect  to  the  rights  of  the  Lender   after  the
reorganization,  reclassification  or  other  transaction  to the end  that  the
provisions of this Section 4 (including adjustments of the Conversion Price then
in effect and the number of shares purchasable upon conversion of the Note under
Sections 1) shall be applicable after that event as nearly  equivalent as may be
practicable.

              4.4  No   Impairment.   The   Company   shall  not,   through  any
reorganization,  dissolution, issue or sale of securities or any other voluntary
action, avoid or seek to avoid the observance or performance of any of the terms
to be observed or  performed  hereunder by the Company but shall at all times in
good faith assist in the carrying out of all the  provisions of Section 4 and in
the taking of all such action as may be  necessary  or  appropriate  in order to
protect the conversion rights of the Lender against impairment.

              4.5  Certificate  as to  Adjustments.  Upon the occurrence of each
adjustment or readjustment of the Conversion  Price pursuant to Section 4.1, the
Company at its expense shall promptly compute such adjustment or readjustment in
accordance with the terms hereof and furnish to the Lender a certificate setting
forth such adjustment or readjustment and showing in detail the facts upon which
such adjustment or readjustment is based.

         5.  Security.  The  Company  hereby  grants to the Lender to secure the
payment and performance of the indebtedness evidenced by this Note, a continuing
perfected first priority  security  interest in and lien on all of the Company's
property and assets, whether real, personal or mixed, or intangible or tangible,
wherever  located,  whether now owned or  hereafter  acquired  or  arising,  all
proceeds and products  thereof and all parts thereof and all accessions  thereto
("Collateral").

         6. Representations and Warranties of Company.

              6.1  The  Company  is  a  corporation   duly  organized,   validly
subsisting, and in good standing under the laws of the State of Utah and has all
requisite  corporate  power  and  authority  to  carry  on its  business  as now
conducted.  The Company is duly  qualified  to transact  business and is in good
standing in each  jurisdiction  in which the failure so to qualify  would have a
material  adverse  effect  on its  business  or  properties  taken as a whole (a
"Material Adverse Effect").

              6.2 The Company has full corporate  power and authority to execute
and deliver  this Note and each other  document or  instrument  contemplated  as
being  executed and  delivered by the Company in  connection  with the Note (the
"Transaction  Documents") and to carry out and perform its obligations under the
terms of the Transaction Documents and the transactions  contemplated hereby and
thereby and to consummate the transactions  contemplated hereby and thereby. The
execution  and  delivery  by the  Company  of the  Transaction  Documents  to be
executed by it in connection herewith,  and the consummation of the transactions
contemplated  hereby and thereby,  have been duly and validly  authorized by all
necessary corporate action on the part of the Company. Each Transaction Document
to be executed by the Company in connection  herewith has been duly executed and

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delivered by the Company,  and,  when duly  executed and  delivered by the other
parties hereto or thereto, shall constitute legal, valid and binding obligations
of the Company, enforceable against it in accordance with their terms subject to
applicable bankruptcy, insolvency,  reorganization,  moratorium and similar laws
affecting  creditors'  rights  and  remedies  generally,   and  subject,  as  to
enforceability,   to  general   principles  of  equity  (regardless  of  whether
enforcement is sought in a proceeding at law or in equity).

              6.3 There is no action,  suit or proceeding,  or, to the Company's
knowledge,  investigation pending or currently threatened against the Company or
any subsidiary of the Company.

              6.4 The Company is not in violation or default of any provision of
its  Articles  of  Incorporation  or  the  Bylaws  of  the  Company,  or of  any
instrument,  judgment, order, writ, decree or contract to which it is a party or
by which it is bound,  or, to its knowledge,  of any provision of any federal or
state  statute,  rule or regulation  applicable to the Company.  The  execution,
delivery and  performance of the Transaction  Documents and the  consummation of
the transactions  contemplated  thereby will not result in any such violation or
be in  conflict  with or  constitute,  with or without  the  passage of time and
giving  of  notice,   either  a  material  default  under  any  such  provision,
instrument,  judgment,  order, writ, decree or contract or an event that results
in the creation of any material lien,  charge or encumbrance  upon any assets of
the  Company  or  the  suspension,   revocation,   impairment,   forfeiture,  or
non-renewal  of  any  material  permit,  license,   authorization,  or  approval
applicable  to the Company,  its business or  operations or any of its assets or
properties.

              6.5 The  Company  is not a party to or bound by any  agreement  of
guaranty,  indemnification,  assumption or endorsement or any like commitment of
the  obligations,  liabilities  (contingent or otherwise) or indebtedness of any
other  person,  corporation  or other entity,  except in the ordinary  course of
business.

              6.6 The  Company is the owner of the  Collateral  and that,  other
than liens for taxes not yet due and payable,  no other person or entity has any
right,  title, claim or interest (by way of lien or otherwise) in, against or to
the  Collateral.  This Note creates a valid security  interest in the Collateral
securing  the  payment  of  the   indebtedness   evidenced  by  this  Note.   No
authorization,  approval or other action by, and no notice to or filing with any
governmental  authority  or  regulatory  body is  required  for the grant by the
Company of the security  interest granted hereby or for the execution,  delivery
or performance of any of the Transaction Documents by the Company.

         7. Representations and Warranties of Lender.

              7.1 Lender has full  corporate  power and authority to execute and
deliver this Note and each other  document or instrument  contemplated  as being
executed and delivered by Lender in connection  with the Note (the  "Transaction
Documents"), to make its representations and warranties herein, and to otherwise
enter into this Note and the documents and transactions  contemplated hereby and
thereby . The execution and delivery by the Lender of the Transaction  Documents
to be  executed  by it in  connection  herewith,  and  the  consummation  of the
transactions  contemplated  hereby  and  thereby,  have  been  duly and  validly
authorized by all  necessary  corporate  action on the part of the Lender.  Each
Transaction  Document to be executed by the Lender in  connection  herewith  has
been duly  executed and  delivered by the Lender,  and,  when duly  executed and
delivered by the other parties hereto or thereto,  shall constitute legal, valid
and binding obligations of the Lender, enforceable against it in accordance with
their  terms  subject  to  applicable  bankruptcy,  insolvency,  reorganization,
moratorium and similar laws affecting  creditors' rights and remedies generally,
and subject,  as to enforceability,  to general principles of equity (regardless
of whether enforcement is sought in a proceeding at law or in equity).

              7.2 Lender is an "Accredited Investor," as that term is defined in
Rule 501(a) of Regulation D promulgated under the Act, because it is one or more
of the following:

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<PAGE>


                     (a) an organization  described in Section  501(c)(3) of the
Internal Revenue Code, a corporation, a Massachusetts or similar business trust,
or a partnership not formed for the specific purpose of acquiring the securities
offered, with total assets in excess of $5,000,000.

                     (b) any other person or entity  described as an "Accredited
Investor" in Rule 501(a) of Regulation D promulgated under the Act.

              7.3 Lender is acquiring the Shares for investment, with no present
intention  of  distributing,  reselling  or  otherwise  disposing  of all or any
portion of the same.

              7.4  Lender  is the  sole  and  true  party  in  interest,  and is
acquiring  the Shares  for its own  account.  No other  person has any direct or
indirect beneficial ownership in this Note.

              7.5 Lender has  experience  in evaluating  and making  speculative
investments,  and has the capacity to protect its interests in  connection  with
the acquisition of the Note and any shares issuable upon conversion of the Note.
Lender has such knowledge and experience in financial and business  matters that
it is capable of evaluating the merits and risks of this transaction.

              7.6 This offer to acquire  the Note and the shares  issuable  upon
conversion  thereof was  directly  communicated  to Lender in such a manner that
Lender was able to ask  questions  of and receive  answers from the Company or a
person  acting  on  its  behalf  concerning  the  terms  and  conditions  of the
transaction. Lender was at no time presented with or solicited by or through any
leaflet, public promotional meeting, television advertisement, or any other form
of general advertising.

              7.7 Lender has received and reviewed the  following  documents and
information from RemoteMDx: (a) RemoteMDx's Annual Report on Form 10-KSB for the
fiscal year ended September 30, 2004; (b) RemoteMDx's  Quarterly Reports on Form
10-QSB for the quarterly periods ended since the date of the Annual Report;  (c)
any Current  Reports on Form 8-K filed by RemoteMDx since the date of the Annual
Report; and (d) RemoteMDx's Proxy Statement  disseminated to its shareholders in
connection with RemoteMDx's Annual Meeting of Shareholders held on May 19, 2004.
Lender  understands  the various risks of an investment in RemoteMDx as proposed
herein and can afford to bear such risks,  including,  without  limitation,  the
risks of losing the entire investment.

         8. General.

              8.1 Collection.  If any action is instituted to collect this Note,
the  Company  promises  to pay to  Lender  all  reasonable  costs  and  expenses
(including reasonable attorneys' fees) incurred in connection with such action.

              8.2  Amendments  and  Waivers.  (a) The  parties  may,  by  mutual
agreement,  amend this Note in any respect, and any party, as to such party, may
(i) extend the time for the  performance of any of the  obligations of the other
party and (ii) waive  compliance  by the other party with any of the  agreements
contained  herein and  performance of any  obligations by the other party. To be
effective,  any such amendment or waiver must be in writing and be signed by the
party  providing  such waiver or  extension,  as the case may be. The rights and
remedies  herein  provided are cumulative and are not exclusive of any rights or
remedies which any party may otherwise  have at law or in equity.  The waiver by
any party  hereto of any breach of any  provision of this Note shall not operate
or be construed as a waiver of any subsequent breach, whether or not similar.

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              8.3 Conflicting  Agreements.  In the event of any  inconsistencies
between  the terms of this Note and the terms of any other  document  related to
the loan evidenced by this Note, the terms of this Note shall prevail.

              8.4  Severability.  The  unenforceability  or  invalidity  of  any
provision or  provisions of this Note as to any persons or  circumstances  shall
not render that provision or those provisions unenforceable or invalid as to any
other  provisions or  circumstances,  and all  provisions  hereof,  in all other
respects, shall remain valid and enforceable.

              8.5 Governing Law. This Note shall be governed by and construed in
accordance  with  the  internal  laws  of  the   Commonwealth  of  Massachusetts
applicable  to  agreements  made  and  to  be  performed   entirely  within  the
Commonwealth of Massachusetts, without regard to the conflicts of law principles
thereof.  The Company and the Lender irrevocably  consent to the jurisdiction of
the courts of the Commonwealth of Massachusetts or the federal courts located in
that state in connection with any lawsuit,  action or proceeding  arising out of
or relating to this Note.

              8.6   Presentment,   Etc.  The  Company  hereby  expressly  waives
presentment,  demand for payment, dishonor, notice of dishonor,  protest, notice
of protest, and any other formality.

              8.7 Waivers.  The  nonexercise  by the Lender of any of its rights
hereunder in any  particular  instance  shall not constitute a waiver thereof in
that or any subsequent instance.

              8.8 Transferability. Neither the Lender nor the Company may assign
or  otherwise  transfer  its rights or  obligations  under this Note without the
prior,  written  consent of the other  party  hereto,  except  that,  subject to
compliance with  applicable  federal and state  securities  laws, the Lender may
transfer  to  an  affiliate  of  Lender;   provided  such  permitted  transferee
acknowledges the securities law restrictions on transferability.


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         IN WITNESS  WHEREOF,  the Company  and Lender  have  caused  their duly
authorized officers to execute this Note as of the date first written above.

                                               CLYDESDALE PARTNERS, LLC

                                               By:
                                               Name:
                                               Title:


                                               REMOTEMDX, INC.


                                               By:
                                               Name:
                                               Title:

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<PAGE>


                                    EXHIBIT A

                              NOTICE OF CONVERSION
                              --------------------



To:               RemoteMDX, Inc.

Attention:        Chief Executive Officer



         The undersigned  hereby elects to convert all or a portion of this Note
into  ______________  shares  of Series C  Preferred  Stock of  RemoteMDX,  Inc.
pursuant to the terms of this Note.

         Please issue a certificate or certificates  representing said shares in
the name of the undersigned or in such other name as is specified below:

                            -----------------------------------

                           (Name)

                            -----------------------------------

                            -----------------------------------

                            -----------------------------------

                            -----------------------------------


                           (Address)


         The  undersigned  hereby  represents  and warrants  that the  aforesaid
shares are being acquired for the account of the  undersigned for investment and
not with a view to, or for resale,  in connection with the distribution  thereof
in a manner that would violate the Securities Act.




                                             -----------------------------------

                                             (Signature and Date)



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