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                                                                  EXHIBIT 99.2

                    PROMISSORY NOTE SECURED BY DEED OF TRUST


$100,000                                                 Tustin, California
                                                         October 17, 1996

        
        FOR VALUE RECEIVED, the undersigned, David L. Schlotterbeck
("Employee") and Genell A. Schlotterbeck, husband and wife (collectively,
"Borrower"), promise to pay to VitalCom Inc., a Delaware corporation (the
"Company"), or order, the principal amount of One Hundred Thousand Dollars
($100,000) together with interest thereon at the rate of five and ninety-four
hundredths percent (5.94%) per annum.  The principal amount hereof and all
accrued and unpaid interest on the outstanding principal amount shall be due
and payable to the holder hereof at 15222 Del Amo Avenue, Tustin, California
92680, or such other place as the holder hereof may designate as follows:

              A.  All accrued and unpaid interest shall be due and payable on
        the first day of each fiscal quarter for the Company commencing on
        January 1, 1997.
              
              B.  The principal amount, if not sooner paid, shall be due and
        payable as follows upon the earlier of the following dates
        (collectively, "Maturity Events"):
                  
                  (1)  Thirty (30) days following the date of voluntary
              termination of the employment of Employee with the Company.

                  (2)  The date of any sale, conveyance, assignment, alienation
              or any other form of transfer, whether voluntary or involuntary,
              of that certain real property commonly known as 26373 Parkside
              Drive, Hayward, California 94542 (the "Property"), or any part or
              interest therein; except that the following transfers of the
              Property shall not be deemed to be a Maturity Event:

                       (a)  A transfer upon the death of Employee to Employee's
                  surviving spouse (provided the surviving spouse is an obligor
                  hereunder) or upon the death of Employee's spouse to Employee;

                       (b)  A transfer by an obligor hereof whereby such
                  obligor's spouse becomes a co-owner of the property
                  transferred;

                       (c)  A transfer resulting from a decree of dissolution of
                  the marriage or legal separation of Employee and Genell A. 
                  Schlotterbeck or from a property settlement agreement
                  incidental to such a decree which requires the obligor spouse
                  to assume responsibility for the obligations under this Note
                  and the second-priority deed of trust encumbering the Property
                  and securing this Note and pursuant to which Employee or
                  Genell A. Schlotterbeck (whoever is the obligor) becomes the
                  sole owner of the property transferred; or



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                       (d) a transfer by one or both obligors under this note
                  into an inter vivos trust in which one or both obligors are
                  beneficiaries.

                  (3)  The third (3rd) anniversary of the date hereof (the
              "Maturity Date").

        The obligations of Borrower under this Note shall be secured by a
second-priority deed of trust (the "Deed of Trust") on that certain real
properly commonly known as 26373 Parkside Drive, Hayward, California.  Borrower
hereby represents and warrants to the Company as follows:

              1.   The Deed of Trust shall be subordinate only to a deed of
        trust made by Borrower, as trustor, for the benefit of ______________
        in the approximate amount of _____________ (the "First Deed of Trust").

              2.   Borrower has good and marketable title to the Property free
        and clear of any security interests, liens or encumbrances other than
        the First Deed of Trust.

        In addition to causing the execution and delivery of the Deed of Trust,
Borrower shall take any and all further actions that may from time to time be
required to ensure that the Deed of Trust creates a valid lien on the Property
in favor of the Company, which shall secure this Promissory Note and be junior
in priority only to the First Deed of Trust: (i) Borrower shall have good and
marketable title to the Property; (ii) the consent of no other person or entity
shall be required to grant a security interest in the Property to the Company;
and (iii) there shall be no deed of trust, mortgage or encumbrance against the
Property other than the First Deed of Trust.  If it should hereafter be
determined that there are defects against title or matters that could result in
defects against title to the Property or that the consent of another person or
entity is required to grant to, and perfect in, the Company a valid
second-priority lien on the Property Borrower shall, promptly on demand by the
Company, take all actions necessary to remove such defects and to obtain such
consent and grant (or cause to be granted) and perfect such lien on the
Property.  Failure of Borrower to comply with the provisions of this paragraph
shall be deemed a default under this Promissory Note and the Deed of Trust.

        In the event that any of the following occurs, then unless otherwise
prohibited by law, the holder hereof shall have the option, without demand or
notice, to declare the entire outstanding principal balance of this Note,
together with all accrued and unpaid interest thereon to be immediately due and
payable: (i) Borrower defaults in the payment of principal or interest when
due pursuant to the terms hereof; (ii) Borrower defaults in its performance of
any obligation contained in the Deed of Trust or any other deed of trust,
security agreement or other agreement (including any amendment, modification or
extension thereof) which may hereafter be executed by Borrower for the purpose
of securing this Note; (iii) any representation or warranty contained in this
Note or the Deed of Trust or any other agreement or instrument executed in
connection with the loan evidenced hereby proves to have been false or
misleading in any material respect; (iv) Borrower defaults in obligation to pay
any indebtedness or to perform any other obligation which is secured by a deed
of trust or other lien on the Property or default under any deed of trust
securing such indebtedness; (v) Borrower defaults in obligation to pay any
indebtedness evidenced



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by any promissory note executed by Borrower and payable to the holder hereof or
there occurs any other default under any deed of trust, mortgage or other
document securing repayment of such indebtedness; or (vi) the amount of the
indebtedness secured by any deed of trust, lien or other encumbrance
encumbering the Property that is senior to the Deed of Trust is increased over
the amount of such indebtedness existing as of the date of this Note.

        In the event any amount owed by Borrower pursuant to this Note is not
paid when due, such unpaid amount shall bear interest from the due date until
paid at a rate equal to the lesser of: (i) ten percent (10%) per annum; or
(ii) the maximum rate permitted by law.  After such due date, all payments
shall be credited first to accrued interest and then to principal.

        If an action is instituted for collection of this Note, Borrower agrees
to pay court costs and reasonable attorneys' fees incurred by the holder
thereof.

        This Note may be amended or modified, and provisions hereof may be
waived, only by the written agreement of Borrower and the holder hereof.  No
delay or failure by the holder hereof in exercising any right, power or remedy
hereunder shall operate as a waiver of such right, power or remedy, and a
waiver of any right, power or remedy on any one occasion shall not operate as a
bar or waiver of any such right, power or remedy on any other occasion.
Without limiting the generality of the foregoing, the delay or failure by the
holder hereof for any period of time to enforce collection of any amounts due
hereunder shall not be deemed to be a waiver of any rights of the holder hereof
under contract or under law.  The rights of the holder hereof under this Note
are in addition to any other rights and remedies which the holder hereof may
have.

        This Note shall be governed by and construed in accordance with the
laws of the State of California.

        This Note may be prepaid at any time without penalty.


BORROWER:                                         BORROWER:


/s/ DAVID L. SCHLOTTERBECK                        /s/ GENELL A. SCHLOTTERBECK
---------------------------                       ----------------------------
    David L. Schlotterbeck                            Genell A. Schlotterbeck



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