<PAGE>

                                                                    EXHIBIT 10.2

                             SECURED PROMISSORY NOTE

$62,500.00                                                         June 10, 2004
                                                            Carlsbad, California

      FOR VALUE RECEIVED, the undersigned, Gregory M. Quist ("Maker"), hereby
promises to pay to JMAR Technologies, Inc., a Delaware corporation ("Payee"), or
order, the principal sum of Sixty-Two Thousand Five Hundred and 00/100 Dollars
($62,500.00). The principal balance shall not accrue interest unless and until
all amounts due hereunder are not paid in full on the date when due, and
thereafter the unpaid amounts due hereunder shall accrue interest at the rate of
ten percent (10%) per annum, or the maximum rate permitted by law if lesser,
computed on the basis of a 365 day year.

      The entire principal of this Note shall be due and payable on the earlier
of 90 days after: (i) the termination of that certain Alliance Agreement, dated
June 10, 2004, among Payee, Maker and David A. Drake ("Alliance Agreement"),
(ii) the failure to complete the acquisition of the CORTS Business (as defined
in the Alliance Agreement) by January 7, 2005 or any extended Closing Date
agreed to by Payee or (iii) the termination of the Purchase Agreement to be
entered into among Maker, Payee and David A. Drake prior to the Closing Date (as
defined therein) following the occurrence of the events listed in Section
4.1(a), (b) or (e) of the Alliance Agreement. In the event that the CORTS
Business is acquired by Payee, as contemplated by the Alliance Agreement, at the
Closing all amounts owing under this Note shall be satisfied through the
application by Payee of said amounts to the purchase price of the CORTS
Business.

      The payment of this Note and the fulfillment of all other obligations of
Maker hereunder are secured by and entitled to all of the benefits of that
certain Security Agreement, dated June 10, 2004, executed by Maker and granting
to Payee a security interest in certain assets of Maker.

      Principal hereunder shall be payable in lawful money of the United States
of America and shall be payable to Payee or any successor holder of this Note at
5800 Armada Drive, Carlsbad, CA 92008, or at such other address as may be
specified in a written notice to Maker given by Payee or any successor holder of
this Note.

      In the event suit is commenced to obtain the payment of any amount payable
hereunder, or to enforce any right of Payee or any successor holder hereunder or
to enforce any obligation of Maker hereunder, the prevailing party to such suit
shall be entitled to reasonable attorneys' fees from the nonprevailing party, as
fixed by the Court.

      Maker shall have the right to prepay all or any part of the principal sum
of this Note, without penalty of any kind whatsoever, at any time or from time
to time.

      IN WITNESS WHEREOF, Maker has caused this Note to be executed by its
officer thereunto duly authorized at Carlsbad, California as of the date first
hereinabove written.

                                                         /s/ Gregory M. Quist
                                                         ----------------------
                                                             Gregory M. Quist

<PAGE>

                             SECURED PROMISSORY NOTE

$62,500.00                                                         June 10, 2004
                                                            Carlsbad, California

      FOR VALUE RECEIVED, the undersigned, David A. Drake ("Maker"), hereby
promises to pay to JMAR Technologies, Inc., a Delaware corporation ("Payee"), or
order, the principal sum of Sixty-Two Thousand Five Hundred and 00/100 Dollars
($62,500.00). The principal balance shall not accrue interest unless and until
all amounts due hereunder are not paid in full on the date when due, and
thereafter the unpaid amounts due hereunder shall accrue interest at the rate of
ten percent (10%) per annum, or the maximum rate permitted by law if lesser,
computed on the basis of a 365 day year.

      The entire principal of this Note shall be due and payable on the earlier
of 90 days after: (i) the termination of that certain Alliance Agreement, dated
June 10, 2004, among Payee, Maker and Gregory Quist ("Alliance Agreement"), (ii)
the failure to complete the acquisition of the CORTS Business (as defined in the
Alliance Agreement) by January 7, 2005 or any extended Closing Date agreed to by
Payee or (iii) the termination of the Purchase Agreement to be entered into
among Maker, Payee and Gregory M. Quist prior to the Closing Date (as defined
therein) following the occurrence of the events listed in Section 4.1(a), (b) or
(e) of the Alliance Agreement. In the event that the CORTS Business is acquired
by Payee, as contemplated by the Alliance Agreement, at the Closing all amounts
owing under this Note shall be satisfied through the application by Payee of
said amounts to the purchase price of the CORTS Business.

      The payment of this Note and the fulfillment of all other obligations of
Maker hereunder are secured by and entitled to all of the benefits of that
certain Security Agreement, dated June 10, 2004, executed by Maker and granting
to Payee a security interest in certain assets of Maker.

      Principal hereunder shall be payable in lawful money of the United States
of America and shall be payable to Payee or any successor holder of this Note at
5800 Armada Drive, Carlsbad, CA 92008, or at such other address as may be
specified in a written notice to Maker given by Payee or any successor holder of
this Note.

      In the event suit is commenced to obtain the payment of any amount payable
hereunder, or to enforce any right of Payee or any successor holder hereunder or
to enforce any obligation of Maker hereunder, the prevailing party to such suit
shall be entitled to reasonable attorneys' fees from the nonprevailing party, as
fixed by the Court.

      Maker shall have the right to prepay all or any part of the principal sum
of this Note, without penalty of any kind whatsoever, at any time or from time
to time.

      IN WITNESS WHEREOF, Maker has caused this Note to be executed by its
officer thereunto duly authorized at Carlsbad, California as of the date first
hereinabove written.

                                                          /s/ David A. Drake
                                                          ---------------------
                                                              David A. Drake