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                                                                    EXHIBIT 10.3

                                    GUARANTY

         1. RELIANCE AND ACKNOWLEDGMENT. The undersigned (the "Guarantor") being
a controlling member and officer of Redwood Consultants, LLC, a California
limited liability company (the "Borrower") or a trust established for the
benefit of such controlling member/officer and deriving substantial personal
benefit from the continue credit or other financial accommodations now or in the
future made to the Borrower by Hypertension Diagnostics, Inc. (the "Lender"),
make this Guaranty as of the date hereof.

         2. GUARANTY. The Guarantor hereby unconditionally guaranties payment of
and promises to pay or cause to be paid to Lender the Obligations (as
hereinafter defined), whether or not the Obligations are valid and enforceable
against the Borrower, whenever the Obligations become due, whether on demand, at
maturity or by reason of acceleration, or at the time the Borrower shall become
the subject of any bankruptcy or insolvency proceeding.

         3. DEFINITION OF OBLIGATION. As used herein, the term "Obligations"
shall mean all debts, liabilities and obligations of every kind of the Borrower
to Lender arising under or in connection with the Note dated October 11, 2001,
made by the Borrower in favor of Lender (the "Note"), and all renewals,
modifications, and extensions thereof, and any other documents executed or
delivered in connection with the Note, whether such debts, liabilities, and
obligations are direct or indirect, absolute or contingent, liquidated or
unliquidated, whether of the same or a different nature and whether existing now
or in the future, including interest thereon and all costs, expenses and
reasonable attorneys' fees paid or incurred by Lender at any time before or
after judgment in attempting to collect any of the foregoing, to realize on any
collateral securing any of the foregoing, and to enforce this Guaranty. The
definition of "Obligations" also includes the amount of any payments required to
be made to Lender or another on behalf of the Borrower which are recovered from
Lender or another party by a trustee, receiver, creditor or other party pursuant
to applicable law (the "Surrendered Payments"). In the event that any
Surrendered Payments are made (including pursuant to a negotiated settlement),
the Surrendered Payments shall immediately be reinstated as Obligations,
regardless of whether Lender has surrendered or canceled this Guaranty prior to
returning the Surrendered Payments. The Guarantor acknowledges that (i) Lender
shall not be obligated to demand payment from or attempt to collect from the
Borrower or any other guarantor, and (ii) Lender shall be under no obligation to
seek pro rata contribution from any other guarantor.

         4. CONSENT TO LENDER ACTIONS; NO DISCHARGE. The Guarantor agrees that
Lender does not have to take any steps whatsoever to proceed against the
Borrower or any other guarantor or surety for the Obligations either before or
after proceeding against the Guarantor and the Guarantor waives any claim of
marshalling of assets against Lender. The Guarantor also agrees that Lender may
do or refrain from doing any of the following without notice to, or the consent
of, the Guarantor, and without reducing or discharging the Guarantor's liability
under this Guaranty: (i) renew, amend, modify, extend or release any existing or
future Obligations (including making additional advances, or changing the
amount, time or manner of payment of any Obligations), and make additional
extensions of credit to the Borrower (which will become additional Obligations),
regardless of when such modifications or additional extensions of credit are
made, and regardless of whether they are similar to or different from any other
Obligations; (ii) amend, supplement and waive compliance with any of the
provisions of the documents evidencing or related to any of the Obligations;
(iii) settle, modify, release, compromise or subordinate any Obligation or the
liability of any other party responsible for payment of any Obligation; and (iv)
accept partial payments, and apply any payments and all other amounts received
from the Borrower or from any other guarantor to the Obligations in any manner
that Lender elects.


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         5. WAIVERS. The Guarantor expressly waives all rights of setoff and
counterclaims, as well as diligence in collection or prosecution, presentment,
demand or payment of performance, protest, notice of dishonor, nonpayment or
nonperformance of any Obligation. The Guarantor also expressly waives notice of
acceptance of this Guaranty, and the right to receive all other notices and
demands of any kind relating to the Obligations or this Guaranty. The Guarantor
will not enforce or exercise any right of contribution, reimbursement, recourse,
or subrogation available to the Guarantor unless and until all of the
Obligations shall have been fully paid and discharged.

         6. BORROWER'S FINANCIAL CONDITION. The Guarantor warrants and
represents to Lender that (i) the Guarantor is sufficiently knowledgeable and
experienced in financial and business matters to evaluate and understand the
risks assumed in connection with the execution of this Guaranty; (ii) the
Guarantor has had the opportunity to examine the records, reports, financial
statements, and other information relating to the financial condition of the
Borrower, (iii) the Guarantor has relied solely upon investigations of the
Borrower's financial condition conducted by the Guarantor or the Guarantor's
authorized representative in deciding to execute this Guaranty; and (iv) the
Guarantor, or the Guarantor's authorized representative, shall continue to
independently review, monitor and investigate the financial condition of the
Borrower while this Guaranty is in effect. THE GUARANTOR SPECIFICALLY RELIEVES
LENDER OF ANY DUTY, OBLIGATION OR RESPONSIBILITY OF ANY NATURE WHATSOEVER TO
ADVISE THE GUARANTOR OF ANY CHANGE IN THE BORROWER'S FINANCIAL CONDITION.

         7. SETOFF. The Guarantor hereby authorizes Lender, without further
notice to anyone, to offset obligations owed to the Guarantor for the amount of
any and all Obligations due under this Guaranty.

         8. DURATION OF GUARANTY; CONTINUING OBLIGATIONS. This is a continuing
Guaranty and shall remain in full force and effect with respect to the Guarantor
until the Obligations are paid in full.

         9. ACCELERATION OF OBLIGATIONS; SUCCESSORS; MULTIPLE GUARANTOR. At such
time as Lender accelerates and declares the unpaid balance of any of the
Obligations due and payable, the Guarantor' liability hereunder to pay such
Obligations shall become immediately due and payable whether or not such
Obligations are then due and payable by the Borrower or any other guarantor.
This Guaranty shall inure to the benefit of Lender, Lender's successors and
assigns and to the holder and owner of any of the Obligations, and shall be
binding on the heirs, executors, administrators, successors and assigns of the
Guarantor.

         10. SEVERABILITY; PRIOR AGREEMENTS; AMENDMENT. The invalidity of any
provision of this Guaranty shall not affect the validity of any other provision.
The Note, the Pledge Agreements and this Guaranty and any other documents
evidencing the Obligations contain the entire agreement of the parties regarding
this matter. Any prior representations, promises or agreements (whether oral or
written) which are not a part of this Guaranty or the documents described above
are not enforceable. The terms of this Guaranty may not be altered, amended or
waived except by another written agreement signed by the Guarantor and Lender.

         11. ANTI-DEFICIENCY WAIVER. The Guarantor hereby waive any and all
defenses that may be available to the Borrower based on any anti-deficiency
statute.

         12. PLEDGE. This Guaranty is secured by Pledge Agreements dated as of
October 11, 2001 with each of the Anthony D. and Leslie T. Altavilla Revocable
Trust, UTA 03/06/2001 and Jens Dalsgaard in favor of Lender (the "Pledge
Agreements").

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         13. GOVERNING LAW; JURISDICTION. This Guaranty shall be governed by the
internal laws of the State of Minnesota. THE GUARANTOR HEREBY CONSENTS TO THE
EXCLUSIVE JURISDICTION OF ANY STATE COURT SITUATED IN THE COUNTY WHERE LENDER IS
LOCATED AND WAIVE ANY OBJECTIONS BASED ON FORUM NON CONVENIENS, WITH REGARD TO
ANY ACTIONS, CLAIMS, DISPUTES OR PROCEEDINGS RELATING TO THIS GUARANTY, ANY
RELATED DOCUMENT, OR ANY TRANSACTIONS ARISING THEREFROM, OR ENFORCEMENT AND/OR
INTERPRETATION OF ANY OF THE FOREGOING. Nothing herein shall affect Lender's
right to serve process in any manner permitted by law, or limit Lender's right
to bring proceedings against the Guarantor in the competent courts of any other
jurisdiction or jurisdictions.

         14. WAIVER OF JURY TRIAL. THE GUARANTOR AND LENDER HEREBY JOINTLY AND
SEVERALLY WAIVE ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING
RELATING TO THIS GUARANTY, THE NOTE, AND ALL DOCUMENTS RELATING TO THIS
GUARANTY, THE OBLIGATIONS HEREUNDER OR ANY TRANSACTION ARISING HEREFROM OR
CONNECTED HERETO. THE GUARANTOR AND LENDER EACH REPRESENTS TO THE OTHER THAT
THIS WAIVER IS KNOWINGLY, WILLINGLY AND VOLUNTARILY GIVEN.

         15. GUARANTOR REPRESENTATIONS AND WARRANTIES. The Guarantor represents
and warrants that the Guarantor possesses sufficient financial means to honor
the commitments under this Guaranty.

         16. COUNSEL. The Guarantor has had the opportunity to consult with
legal counsel of Guarantor's own choosing and has done so to the extent
Guarantor believes necessary and appropriate in Guarantor's sole judgment.

                              [signature next page]







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Dated: October 11, 2001

                                            GUARANTOR:


                                            ANTHONY D. AND LESLIE T. ALTAVILLA
                                            REVOCABLE TRUST, UTA 03/06/2001


                                              /s/  Anthony D. Altavilla, Trustee
                                            ------------------------------------
                                            Anthony D. Altavilla, Trustee


                                              /s/  Leslie T. Altavilla, Trustee
                                            ------------------------------------
                                            Leslie T. Altavilla, Trustee



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Dated: October 11, 2001                     GUARANTOR:



                                             /s/  Anthony D. Altavilla
                                            ------------------------------------
                                            Anthony D. Altavilla, an individual












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Dated: October 11, 2001                     GUARANTOR:

                                            /s/  Jens Dalsgaard
                                            ------------------------------------
                                            Jens Dalsgaard, an individual





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