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EXHIBIT 10.40.2

THE SECURITIES  REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933 AND MAY NOT BE RESOLD OR  HYPOTHECATED  BY THE  HOLDER  UNLESS  SUCH
TRANSFER  COMPLIES WITH AN EXEMPTION FROM THE REGISTRATION  REQUIREMENTS OF SAID
ACT.  ACCEPTANCE OF THIS NOTE CONSISTUTES THE HOLDER'S  REPRESENTATION  THAT THE
HOLDER  TAKES  THIS  NOTE  FOR  INVESTMENT  AND  NOT  WITH A VIEW TO  RESALE  OR
DISTRIBUTION.

                                                                     Note No. 01

                              UNSECURED CONVERTIBLE

                                 PROMISSORY NOTE

$1.00                                                              April 1, 2003
Irvine, California

         HiEnergy  Technologies,  Inc., a Delaware  corporation  ("Maker"),  for
value received,  hereby promises to pay YOCCA,  PATCH & YOCCA, LLP, a California
limited liability  partnership,  or order ("Holder"),  at 19900 MacArthur Blvd.,
Suite 650,  Irvine,  California  92612,  or at such other place as designated in
writing by Holder,  the principal sum of One Dollars and No Cents ($1.00),  with
interest  thereon  at the  rate of ten  percent  (10%)  per  annum  on the  then
outstanding  principal  balance  computed  on the  basis of a  365-day  year and
charged  on the basis of  actual  days  elapsed  minus  thirty  (30)  days.  The
outstanding  principal  balance,  together  with any and all  accrued but unpaid
interest shall all be due and payable in full on or before 5:00 p.m., California
time,  September 15, 2003 (the "Maturity Date").  Interest shall accrue from and
after the date of this Unsecured Convertible  Promissory Note ("Note"),  payable
in full on or before the Maturity Date. All sums payable  pursuant  hereto shall
be payable in lawful money of the United States of America.  Payments made under
this Note shall be first credited to fees or costs due under this Note,  then to
accrued interest and lastly to outstanding  principal.  Unpaid interest shall be
added to  principal on each  anniversary  of the date of this Note and bear like
interest.

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                              TERMS AND CONDITIONS

         Section 1. PREPAYMENT.  Maker may prepay this Note in whole or in part,
without  penalty,  at any time and from  time to time  upon  thirty  days  prior
written notice to Holder (the "Notice").

         Section 2. DEFAULT.  If any of the following  events (each  hereinafter
called individually an "Event of Default") shall occur:

                  (a) If Maker  shall  default  in the  payment of any amount on
this Note when the same shall become due and payable,  whether at maturity or by
acceleration or otherwise, or otherwise default under this Note; or

                  (b) If Maker  shall  make an  assignment  for the  benefit  of
creditors; or

                  (c) If Maker shall file a voluntary petition in bankruptcy, or
shall be  adjudicated  a bankrupt or  insolvent  under the present or any future
Federal Bankruptcy Act or other applicable federal,  state or other statute, law
or regulation; or

                  (d) In the event of a  liquidation,  dissolution or winding up
of the  Maker,  whether  voluntary  or  involuntary,  or a sale,  or a series of
related  sales,  of all or  substantially  all of the assets of the Maker,  or a
sale, or a series of related sales, or exchange,  of capital stock of the Maker,
either by the Maker or its  shareholders,  such  that the  Maker's  shareholders
immediately  before  such  transaction  do not hold (by virtue of such shares or
securities  issued solely with respect thereto) more than fifty percent (50%) of
the  voting  power  of  the  surviving  or  continuing   entity,  or  a  merger,
consolidation,  acquisition of property or shares,  separation or reorganization
of the Maker with one or more entities,  corporate or otherwise,  as a result of
which the  Maker is not the  surviving  corporation  or as a result of which the
holders  of stock of the  Maker as of prior to the  transaction  do not hold (by
virtue of such shares or  securities  issued  solely with respect  thereto) more
than fifty  percent  (50%) of the voting power of the  surviving  or  continuing
entity; or

then,  and in each and every such case, the Holder of this Note may by notice in
writing to the Maker declare all amounts under this Note to be forthwith due and
payable  (except that,  in the case of an Event of Default under either  Section
2(b) or Section 2(c), this Note shall become immediately due and payable without
notice) and  thereupon  the balance  shall  become so due and  payable,  without
presentation,  protest or further demand or notice of any kind, all of which are
hereby  expressly  waived.  The Maker  shall give  promptly a written  notice to
Holder of the  occurrence or the approval by the Maker or its Board of Directors
of any and all of the foregoing  events,  and in any of the events under Section
2(d) or Section  2(e),  such notice  shall be given at least  fifteen  (15) days
prior to the anticipated effective date of the transaction. In addition, upon an
Event of Default,  Holder may  exercise  any and all other  rights and  remedies
Holder has at law, in equity or  otherwise.  All  remedies  are  cumulative.  No
single or partial  exercise of Holder of any right  hereunder shall preclude any
other or further exercise thereof or the exercise of any other right.

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         Section 3. NO WAIVER.  No waiver by Holder of any  default of breach by
Maker  under this Note shall be implied  from any delay or omission by Holder to
take action on account of such default if such default  persists or is repeated;
no express waiver shall affect any default other than the default expressly made
the subject of the waiver and any such express  waiver  shall be operative  only
for the time and to the extent therein stated. Any waiver of any covenant,  term
or  condition  contained  herein  shall  not be  construed  as a  waiver  of any
subsequent  breach of the same  covenant,  term or  condition.  The  consent  or
approval  by  Holder  to or of any act by Maker  requiring  further  consent  or
approval  shall  not be deemed to waive or render  unnecessary  the  consent  or
approval to or of any subsequent similar act.

         Section 4.  COLLECTION  COSTS.  Maker  covenants that, upon an Event of
Default,  it shall pay to the person  entitled  to  receive  such  payment  such
further amount,  to the extent lawful,  as shall be sufficient to cover the cost
and expense of collection  and  enforcement of this Note,  including  reasonable
attorneys' fees and costs,  court costs, costs of appeal and costs of collection
and enforcement of any judgment.

         Section 5.  SUCCESSORS/LIABILITY.  This Note shall be binding  upon the
successors and assigns of Maker and shall inure to the benefit of Holder and its
successor and assigns. Diligence, demand, notice, presentment,  notice of intent
to accelerate the maturity of this Note are waived by Maker.  This Note shall be
governed  by  and  construed  in  accordance  with  the  laws  of the  State  of
California.

         Section 6. COMPLIANCE WITH LAW. It is Maker's and Holder's intention to
comply with any applicable usury law. In furtherance of this intention of Holder
and Maker, all agreements between Maker and Holder are expressly limited so that
in no event  whatsoever shall the amount paid or agreed to be paid to Holder for
the use,  forbearance  or  detention of money under this Note exceed the maximum
permissible under applicable law. If, for any reason whatsoever,  fulfillment of
any provision  hereof shall be prohibited by law, the obligation to be fulfilled
shall be  reduced to the  maximum  amount so  prohibited,  and if for any reason
Holder should have received as interest an amount which would exceed the highest
lawful  rate,  such amount  which would be in excess of the  permitted  interest
shall, at Holder's option, be applied to the reduction of principal of this Note
and not to the payment of  interest,  or be refunded  to Maker.  This  provision
shall control any other provision of all agreements between Maker and Holder.

         Section 7. TRANSFER.  Subject to the  restrictions  and  limitations on
transfer under federal or state securities laws, upon surrender of this Note for
transfer or exchange,  a new Note or new Notes of the same tenor, dated the date
to which  interest  has been paid on the  surrendered  Note and in an  aggregate
principal   amount  equal  to  the  unpaid  principal  amount  of  the  Note  so
surrendered,  will be issued to and  registered in the name of the transferee or
transferees.

         Section 8. NOTE REGISTER. This Note is transferable only upon the books
of the Maker that Maker shall maintain for such purpose. The Maker may treat the
registered  holder of this Note as he or it appears on the Maker's  books at any
time as the Holder for all purposes.

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         Section 9. LOSS,  ETC., OF NOTE. Upon receipt of evidence  satisfactory
to the Maker of the loss, theft,  destruction or mutilation of this Note, and of
indemnity reasonably satisfactory to the Maker if lost, stolen or destroyed, and
upon  surrender  and  cancellation  of this Note if  mutilated,  the Maker shall
execute  and  deliver  to  the  Holder  a new  Note  of  like  date,  tenor  and
denomination.

         Section 10. LEGAL  REPRESENTATION.  Yocca Patch & Yocca, LLP represents
and has represented Maker in specific matters, and has agreed at Maker's request
to accept payment in the form of this long-term Note rather than payment in cash
within 30 days, as is the normal practice.  Maker's  interests in this Note are,
or at least  potentially are, adverse to those of the Holder.  Maker understands
and acknowledges  that (a) this Note is an  unconditional  obligation to pay the
indebtedness represented by this Note, plus interest at the maximum lawful rate,
unless  converted  at the Holder's  option;  (b) this Note is  convertible  into
securities  of  Maker  at the  option  of  the  Holder;  (c)  this  Note  may be
accelerated in the events described in Section 2 of this Note; and (d) if unpaid
when due, the Maker shall be  responsible  to pay Holder's  attorneys'  fees and
costs of collection  in addition to the amounts  otherwise  due.  Maker has been
advised by Yocca Patch & Yocca to discuss this Note,  before  signing this Note,
with  independent  counsel  of  Maker's  choice to be  advised  in regard to the
benefits,  risks or any other  aspect  of this  Note.  Also,  this Note is in an
amount equal to Yocca Patch & Yocca,  LLP's billings as of a recent date,  which
Maker has reviewed and approved prior to signing this Note.

         Section 11. AUTHORIZATION. Maker represents and warrants to Holder that
the  undersigned  are duly  elected and acting  officers  of Maker,  holding the
offices  indicated below, and duly and validly  authorized by the Maker's Bylaws
to execute  and  deliver  and cause the Maker to perform  this Note  without any
further corporate action.

         Section 12. CONVERSION. The Holder shall have the right to convert (the
"Conversion  Right"),  on the terms and conditions  hereinafter  set forth,  the
principal amount and accrued interest,  costs or other charges of this Note that
is then  outstanding,  in whole or in part,  into a number  of  shares of Common
Stock,  $.001 par value  ("Stock") of the Maker equal to the result  obtained by
dividing  the  principal  amount  of the Note  then  outstanding  by One  Dollar
($1.00),  subject to adjustment as described below (the "Conversion Price"). The
period  during  which the Holder shall be entitled to elect to convert this Note
then  outstanding,  or any portion thereof,  into Stock of Maker pursuant hereto
shall  be from  the  date of this  Note  until  the  later  of the  date set for
prepayment  by the Notice or the date of  payment of this Note (the  "Conversion
Period").  If Holder fails to make such election to convert the then outstanding
principal amount of this Note, in the manner  hereinafter set forth,  within the
Conversion  Period,  the  Conversion  Right granted  hereunder  shall  terminate
automatically  and be of no further  force or effect with respect to the portion
of this Note so  repaid.  In the event  Notice is  withdrawn  by Maker  prior to
payment,  or for any reason  payment is not made on the date set in the  Notice,
the  Conversion  Right granted under this Section1  shall not terminate and, the
Holder shall

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again have the  Conversion  Right granted under this Section with respect to the
principal amount of this Note then outstanding. If the Holder desires to convert
all or part of this Note,  on the terms set forth in this  Section,  into Stock,
then, during the Conversion Period, the Holder must give written notice to Maker
of such  Holder's  election to convert this Note as  aforesaid,  which  election
shall be irrevocable.  Then, the Maker will cause one or more stock certificates
evidencing the Holder's  ownership of the number of Conversion Shares into which
this Note has been converted as aforesaid to be delivered promptly to the Holder
against  surrender to Maker of the original of this Note or a replacement  for a
lost, stolen or destroyed Note. The Maker shall cause the Conversion Price to be
adjusted  from  time to time in case  Maker  shall (i) pay a  dividend  or other
distribution of shares of the Stock to the holders of the outstanding  shares of
such class of Stock, (ii) subdivide the outstanding shares of the class of Stock
into  which this Note is  convertible  into a greater  number of  shares,  (iii)
combine the outstanding shares of Stock into which this Note is convertible into
a smaller number of shares, or (iv) merge or otherwise  reorganize or reclassify
the Stock. In the event of each of the foregoing, the Conversion Price in effect
immediately  prior  thereto  shall be  adjusted  so that the  Holder of the Note
thereafter surrendered for conversion shall be entitled to receive the number of
shares of Stock, or other shares or property,  which he would have owned or have
been entitled to receive had the Note been  converted  immediately  prior to the
happening of such event at the same aggregate  Conversion  Price.  An adjustment
made  pursuant to this Section  shall  become  effective  immediately  after the
record date in the case of a dividend or distribution and shall become effective
immediately  after the effective date in the case of subdivision or combination.
Such adjustments will be made  sequentially  upon the happening of more than one
of the events described above.

         IN WITNESS WHEREOF, Maker has caused this Note to be executed as of the
date set forth above.

                      HiEnergy Technologies, Inc.,
                      a Delaware corporation

                      By:  /S/ BOGDAN C. MAGLICH
                           ------------------------------------------------
                               Bogdan C. Maglich, Chief Executive Officer


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