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                                                                   EXHIBIT 10.48

NOTWITHSTANDING ANYTHING TO THE CONTRARY HEREIN, ENFORCEMENT OF THE MORTGAGES IS
LIMITED TO A DEBT AMOUNT OF $1,000,000.00 UNDER CHAPTER 287 OF MINNESOTA
STATUTES.

                    COMBINATION MORTGAGE, SECURITY AGREEMENT,
                             ASSIGNMENT OF RENTS AND
                           FIXTURE FINANCING STATEMENT

         THIS COMBINATION MORTGAGE, SECURITY AGREEMENT, ASSIGNMENT OF RENTS AND
FIXTURE FINANCING STATEMENT dated as of October 28, 2003 (the "Mortgage"), by
and between HEI, INC. a Minnesota corporation, whose address is 1495 Steiger
Lake Lane, Victoria, MN 55386 (the "Mortgagor"), and COMMERCE FINANCIAL GROUP,
INC., a Minnesota state banking corporation, whose address is 7650 Edinborough
Way, Suite 160, Edina, MN 55435 (the "Mortgagee");

                                   WITNESSETH:

         WHEREAS, Mortgagor is justly indebted to Mortgagee in the principal
amount of One Million One Hundred Fifty Thousand and No/100ths Dollars
($1,150,000.00) as evidenced by a certain promissory note in said amount made by
Mortgagor payable to the order of Mortgagee dated of even date herewith (the
"Note"), which Note shall mature on or before SEPTEMBER 28, 2007, and the
principal of which Note bears interest as provided therein, which Note is fully
incorporated herein by reference;

         WHEREAS, the total principal amount of the Note is to be advanced
pursuant to the terms and conditions of a certain Term Loan Agreement dated of
even date herewith by and between Mortgagor, as borrower Mortgagee as lender
(the "Loan Agreement"), which Loan Agreement is fully incorporated herein by
reference (capitalized terms used herein and not otherwise defined shall have
the meaning ascribed to them in the Loan Agreement);

         WHEREAS, Mortgagor has agreed to mortgage and grant a security interest
in the Mortgaged Property, as herein defined, to secure payment of the Note and
its obligations under the Loan Agreement, and this Mortgage;

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         NOW, THEREFORE, in consideration of One Dollar ($1.00) and other good
and valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, and to secure the due and punctual payment of the principal,
prepayment premium (if applicable) and interest on the Note, as it may be
extended, amended or renewed, all other sums due and owing on the Note and the
Loan Agreement, and the payment of all fees, sums, expenses and advances of
Mortgagee made in accordance with the terms of this Mortgage, with interest
thereon at the rate equal to that specified in Note (collectively called the
"Indebtedness"), Mortgagor does hereby grant, bargain, sell, convey, release,
mortgage and warrant, grant a security interest in and pledge unto Mortgagee,
its successors and assigns, forever, the following:

                            A. LAND AND IMPROVEMENTS

         All of its right, title and interest in and to (i) the tracts, parcels
and interests in land, and any street or alleys adjoining said premises
heretofore or hereafter vacated, lying and being in the County of Carver, State
of Minnesota, as legally described on Exhibit A hereto and made a part hereof
(the "Land"); (ii) all of the buildings, including, without limitation, the
existing building, structures, fixtures, annexations and other improvements now
standing or at any time hereafter constructed or placed upon the Land (the
"Improvements"); (iii) all extensions, additions, improvements, betterments,
renewals and replacements of any of the foregoing; and (iv) all hereditaments,
easements, rights, privileges and appurtenances now or hereafter belonging,
attached or in any way pertaining to the Land or to any of the Improvements; and

                              B. PERSONAL PROPERTY

         All property now or hereafter affixed or attached to or incorporated
upon the Land or the Improvements which is now or hereafter owned by Mortgagor
or in which Mortgagor now or hereafter has an interest, which to the fullest
extent permitted by law, shall be deemed fixtures and a part of the real
property (the "Personal Property"), including but not limited to (i) all
building materials, supplies and equipment now or hereafter located on the Land
and suitable or intended to be incorporated in any building, structure or other
improvement located or to be erected on the Land; (ii) all heating, plumbing and
lighting apparatus, screens, awnings, floor coverings, shrubbery, plants,
landscaping, motors, engines, machinery, elevators, electrical equipment,
incinerator apparatus, air conditioning equipment, water and gas apparatus,
pipes, boilers, furnaces, cleaning, communication and sprinkler systems,
faucets, fire extinguishing apparatus and equipment, and all other fixtures of
every description which are now or may hereafter be placed or used upon the Land
or in any building, structure or other improvement now or hereafter located
thereon; and (iii) all additions, accessions, increases, parts, fittings,
accessories, replacements, substitutions, betterments, repairs, products and
proceeds to and of any and all such Personal Property (but excluding therefrom
the inventory and removable personal property of the Mortgagor or any tenant of
the Land or the Improvements).

         TO HAVE AND TO HOLD the Land, Improvements and Personal Property
(collectively called the "Property" or the "Mortgaged Property"), together with
all privileges, hereditaments and appurtenances thereunto now or hereafter
belonging, or in any wise appertaining, and the proceeds thereof, unto
Mortgagee, forever;

                                      -2-

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         PROVIDED, NEVERTHELESS, that these presents are upon the express
condition that if Mortgagor shall pay or cause to be paid the Indebtedness, and
if Mortgagor shall duly and punctually perform and observe all of the terms,
covenants, agreements and conditions contained in this Mortgage, the Loan
Agreement, and the Note, then this Mortgage and the estate, right and interest
of Mortgagee in and to the Mortgaged Property shall cease and be and become void
and of no force and effect, and shall be satisfied at Mortgagor's expense;
otherwise this Mortgage shall remain in full force and effect.

         Mortgagor and Mortgagee further agree as follows:

                                    ARTICLE I

                  GENERAL COVENANTS, AGREEMENTS AND WARRANTIES

         Section 1.01. Warranty of Title; Permitted Encumbrances. Mortgagor
covenants, represents and warrants that (a) it is the lawful owner of and has
good right and lawful authority to grant, bargain, sell, convey, release,
mortgage, grant a security interest in, and pledge the Mortgaged Property as
provided herein, (b) it is and will continue to be well and truly seized of good
and marketable title to the Mortgaged Property, (c) the Mortgaged Property is
and will remain throughout the term of this Mortgage free and clear of all
mortgages, liens, pledges, charges and encumbrances, excepting only the lien of
this Mortgage and such Permitted Encumbrances as are listed on Exhibit B
attached hereto and made a part hereof, and (d) Mortgagor warrants and will
defend the title to the Mortgaged Property against all claims and demands
whatsoever not specifically excepted herein.

         Section 1.02. Payment of Indebtedness; Observance of Terms and
Covenants. Mortgagor shall duly and punctually (a) pay each and every
installment of principal and interest on the Note and all other portions of the
Indebtedness, as and when the same shall become due, and (b) perform and observe
all of the terms, covenants, agreements and conditions contained in this
Mortgage, the Loan Agreement and the Note and all other documents and
instruments given as security for the payment of the Note.

         Section 1.03. Validity; Enforceable Obligations. Mortgagor covenants,
represents and warrants that (a) the Note, this Mortgage, the Loan Agreement,
and all other documents and instruments executed and delivered by it in
connection with the execution and delivery of the Note have been duly executed
and delivered and are valid and enforceable obligations of Mortgagor in
accordance with the terms thereof and hereof, and (b) this Mortgage does not,
nor does the Note, nor does the Loan Agreement, nor does the performance or
observance by Mortgagor of any of the matters or things in this Mortgage or the
Loan Agreement provided for, contravene any covenant in any indenture or
agreement affecting Mortgagor or any of its properties.

         Section 1.04. Additional Assurances. Mortgagor shall (a) do, execute,
acknowledge and deliver all and every further act, deed, conveyance, transfer
and assurance reasonably necessary or proper for the carrying out more
effectively of the purpose of this Mortgage and the Loan Agreement and, without
limiting the foregoing, for conveying, mortgaging, assigning, and confirming
unto Mortgagee all of the Mortgaged Property or property intended so to be,
whether now owned or hereafter acquired, including without limitation the
preparation, execution and filing of any documents, such as financing statements
and continuation statements, deemed advisable by

                                      -3-

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Mortgagee for maintaining its lien on any part of the Mortgaged Property, and
(b) pay any and all recording fees, filing fees, mortgage registry tax, stamp
taxes or other charges arising out of or incident to the filing or recording of
this Mortgage, such further assurances and instruments and the issuance and
delivery of the Note.

         Section 1.05. Maintenance and Repairs. Mortgagor shall (a) cause the
Mortgaged Property and every part thereof to be maintained, preserved and kept
in safe and good repair, working order and condition, and will comply with all
laws and regulations of any governmental authority with reference to the
Mortgaged Property and the manner of using or operating the same, and with all
restrictive covenants, if any, affecting the title to the Mortgaged Property, or
any part thereof, (b) from time to time make all necessary and proper repairs,
renewals, replacements, additions and betterments to the Mortgaged Property and
every part thereof so that the value and efficient use thereof shall be fully
preserved and maintained and so that all laws and regulations as aforesaid shall
be complied with, and (c) promptly repair and restore the Mortgaged Property and
every part thereof which may become damaged or destroyed by fire, casualty or
otherwise to their condition prior to any such damage or destruction.

         Section 1.06. Removal of Mortgaged Property. Mortgagor shall not
without the prior written consent of Mortgagee (a) remove the Improvements or
Personal Property or any part thereof from the Land, except that as long as no
Event of Default, as herein defined, shall occur and be continuing, Mortgagor
may remove and dispose of any item or items of Personal Property which have
become inadequate, obsolete or worn out, provided Mortgagor immediately replaces
said item or items of Personal Property with like property such that the value
of the Mortgaged Property will not be materially diminished, which shall become
a part of the Mortgaged Property and subject to the lien of this Mortgage, (b)
demolish, alter or modify the Improvements or Personal Property or any part
thereof nor construct additional improvements on the Land, or (c) abandon or
vacate the Mortgaged Property or any part thereof.

         Section 1.07. Payment of Operating Costs, Prior Mortgages and Liens.
Mortgagor shall pay all operating costs and expenses of the Mortgaged Property
and keep the same free from mechanics', materialmen's and other liens, levy,
execution or attachment. Mortgagor shall also pay when due all indebtedness
which may be secured by any mortgage, lien or charge on the Mortgaged Property
superior to or equal to the lien of this Mortgage, and upon request exhibit to
Mortgagee satisfactory evidence of such payment and discharge.

         Section 1.08. Payment of Taxes. Mortgagor shall (a) pay when due and
before any penalty attaches thereto all taxes, assessments, water charges, sewer
charges, and other fees, taxes, charges and assessments of every kind and nature
whatsoever assessed or charged against or constituting a lien on the Mortgaged
Property or any interest therein, upon or against the Note or the Indebtedness
or upon or against the interest of Mortgagee in the Mortgaged Property or in the
Note or Indebtedness (the "Taxes"), and (b) upon demand furnish to Mortgagee
proof of the payment of any such Taxes. In the event of a court decree or an
enactment after the date hereof by any legislative authority of any law imposing
upon a mortgagee the payment of the whole or any part of the Taxes herein
required to be paid by Mortgagor, or changing in any way the laws relating to
the taxation of mortgages or debts secured by mortgages or a mortgagee's
interest in mortgaged premises, so as to impose such Tax on Mortgagee or on the
interest of Mortgagee in the Mortgaged Property, then, in any such event,
Mortgagor agrees that it shall bear and pay the full amount of such Tax.

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         Section 1.09. Contest of Taxes and Liens. Notwithstanding any other
provision of this Mortgage to the contrary, Mortgagor will not be required to
pay, discharge or remove any Tax, or any lien against the Mortgaged Property or
any part thereof, including a mechanic's lien (a "Lien") so long as Mortgagor
shall in good faith contest the same or the validity thereof by appropriate
legal proceedings which shall operate to prevent the collection of the Tax or
Lien so contested and the sale of the Mortgaged Property, or any part thereof,
to satisfy the same, provided that Mortgagor shall, prior to the date such Tax
or Lien is due and payable, have given to Mortgagee cash or provided such other
reasonable security as may be required by Mortgagee to insure such payment and
interest and penalties thereon and prevent any sale or forfeiture of the
Mortgaged Property by reason of such nonpayment. Any such contest shall be
prosecuted with due diligence and Mortgagor shall promptly after final
determination thereof pay the amount of any such Tax or Lien so determined,
together with all interest and penalties thereon, which may be payable in
connection therewith. Notwithstanding the provisions of this Section, Mortgagor
shall (and if Mortgagor shall fail so to do, Mortgagee may, but shall not be
required to) pay any such Tax or Lien notwithstanding such contest if in the
reasonable opinion of Mortgagee the Mortgaged Property, or any part thereof,
shall be in jeopardy or in danger of being forfeited or foreclosed.

         Section 1.10. Protection of Security. Mortgagor shall promptly notify
Mortgagee of and appear in and defend any suit, action or proceeding that
affects the Mortgaged Property, the Indebtedness or the rights or interest of
Mortgagee hereunder. Mortgagee may elect to appear in or defend any such action
or proceeding and Mortgagor agrees to indemnify and reimburse Mortgagee from any
and all loss, damage, expense or cost arising out of or incurred in connection
with any such suit, action or proceeding, including without limitation, all
reasonable sums paid by Mortgagee to establish or defend the rights and lien of
this Mortgage or to protect the Mortgaged Property or any part thereof,
including costs of evidence of title and reasonable attorneys fees, which
amounts shall be paid by Mortgagor to Mortgagee upon demand together with
interest thereon from the date of payment by Mortgagee at the rate equal to that
specified in the Note.

         Section 1.11.  Prohibition of Sale, Lease and Mortgage.  In the event:

                  (a) Mortgagor sells, leases, conveys, transfers, assigns,
         further mortgages or encumbers or disposes of the Mortgaged Property or
         any part thereof, or any interest therein, or agrees to do so, or
         except as otherwise provided in Section 1.06 hereof; or

                  (b) the Mortgaged Property, or any material part thereof, is
         condemned or the use or control thereof is taken in any proceedings
         involving the right of eminent domain;

whether occurring by voluntary or involuntary act or by operation of law or
otherwise, without the written consent of the Mortgagee being first obtained,
then at the sole option of the Mortgagee, Mortgagee may declare an Event of
Default to have occurred under this Mortgage, thereby entitling Mortgagee to
exercise any and all rights and remedies available to it as provided in this
Mortgage upon the occurrence of an Event of Default. In the event Mortgagor
shall request the consent of Mortgagee in accordance with this Section 1.11,
Mortgagor shall deliver a written request to Mortgagee together with complete
information regarding such a conveyance, lease or encumbrance and shall allow
Mortgagee 30 days from the date of receipt thereof for evaluation of such
request. Such approval may be subject to such other modifications of the loan
terms as may be deemed

                                      -5-

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necessary by Mortgagee. Consent as to any one transaction shall not be deemed to
be a waiver of the right to require consent to future or successive
transactions.

         Section 1.12. Loan Agreement. This Mortgage is the Mortgage referred to
in and is also given as security for the due and punctual performance,
observance and payment by Mortgagor of the terms and conditions set forth in the
Loan Agreement and the Note. In the event Mortgagor fails to comply with any of
such terms and conditions, such failure shall be an Event of Default under this
Mortgage entitling Mortgagee to exercise any and all remedies available to it as
provided in this Mortgage upon the occurrence of an Event of Default. In
addition, Mortgagee may, but shall not be required to, avail itself of any or
all of the rights and remedies available to it under the Loan Agreement, and any
sums expended by Mortgagee in availing itself of such rights and remedies shall
bear interest thereon from the date of such expenditures at the rate equal to
that specified in the Note, shall constitute a portion of the Indebtedness
secured hereby, and shall be payable to Mortgagee immediately upon demand,
provided that, no such payment by Mortgagee shall be considered as waiving the
Event of Default.

                                   ARTICLE II

                              INSURANCE AND ESCROWS

         Section 2.01. Insurance. Mortgagor shall procure and keep in full force
and effect during the term of this Mortgage, at its sole cost and expense, the
following:

                  (a) insurance covering the Mortgaged Property against all
         risks of loss or damage to the Mortgaged Property, including but not
         limited to loss or damage caused by fire and extended coverage perils,
         including the cost of debris removal, together with vandalism,
         malicious mischief, sprinkler leakage, and agreed amount endorsements,
         all in amounts of not less than the full replacement cost of the
         Improvements and Personal Property;

                  (b) to the extent pressure fired boilers are located on the
         Mortgaged Property, insurance covering the Mortgaged Property against
         loss or damage by explosion, and providing for full repair and full
         replacement cost coverage;

                  (c) such other insurance covering the Mortgaged Property
         against loss or damage by other casualties and contingencies as
         Mortgagee may from time to time reasonably require, all in such manner
         and for such amounts as may be satisfactory to Mortgagee;

                  (d) flood insurance in the maximum amount obtainable, unless
         evidence is provided that the Mortgaged Property is not within a flood
         plain as defined by the Federal Insurance Administration;

                  (e) use and occupancy insurance covering risk of loss due to
         the occurrence of any hazards described in the foregoing Subsections
         (a), (b), (c) and (d) in an amount equal to guaranteed income from the
         Mortgaged Property for a period of nine (9) months and based upon a
         reasonable estimate of annual income from Mortgagor's use of the
         Mortgaged Property; and

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                  (f) comprehensive general public liability insurance covering
         the liability of Mortgagor for claims for bodily injury, death or
         property damage occurring on, in or about the Mortgaged Property in
         amounts not less than Two Million Dollars ($2,000,000) per occurrence
         for bodily injury and Five Hundred Thousand Dollars ($500,000) per
         occurrence for property damage or such greater amounts as shall, from
         time to time, be required by Mortgagee.

The policy or policies of such insurance shall (i) be written on forms and with
insurance companies satisfactory to Mortgagee, (ii) as to property insurance,
contain agreed amount endorsements for not less than the full replacement cost
of the Improvements and Personal Property, (iii) as to liability insurance, name
as the insured parties Mortgagor and Mortgagee as their interests may appear,
(iv) bear a mortgagee clause in favor of Mortgagee in form satisfactory to
Mortgagee, all with loss proceeds under such policies to be made payable to
Mortgagee; and (v) be in such amounts as Mortgagee from time to time may
require.

         All policies of insurance shall specifically provide that Mortgagee
shall receive 30 days prior written notice before cancellation of any such
policies. In the event of a foreclosure of this Mortgage or any acquisition of
the Mortgaged Property by Mortgagee all such policies and any proceeds payable
therefrom, whether payable before or after a foreclosure sale, or during the
period of redemption, if any, shall become the absolute property of Mortgagee to
be utilized at its discretion. In the event of foreclosure or the failure to
obtain and keep any insurance required herein, Mortgagor empowers Mortgagee to
effect insurance upon the Mortgaged Property at Mortgagor's expense and for the
benefit of Mortgagee in the amounts and types aforesaid for a period of time
extending through the time of redemption from foreclosure sale, and if necessary
therefore, to cancel any or all existing insurance policies. Mortgagor agrees to
furnish Mortgagee copies of all inspection reports and insurance recommendations
received by Mortgagor from any insurer.

         Section 2.02. Escrows. From and after the occurrence of any Event of
Default, Mortgagor shall deposit with Mortgagee on the first day of each and
every month hereafter, an amount equal to one-twelfth (1/12th) of the annual
taxes and assessments (the "Charges") due on or relating to the Mortgaged
Property as estimated by Mortgagee. From time to time out of such deposits and
to the extent such deposits are sufficient Mortgagee will, upon presentation to
Mortgagee by Mortgagor of bills therefor, pay the Charges or will upon
presentation of receipted bills therefor, reimburse Mortgagor for such payments
made by Mortgagor. In the event (a) the deposits on hand are not sufficient to
pay all of the Charges when the same become due from time to time, or (b)
Mortgagee estimates that the current monthly deposits are less than the
estimated monthly amounts necessary to pay the Charges as they become due from
time to time, then Mortgagor shall pay to Mortgagee on demand the amount
necessary to make up the deficiency. The excess of any such deposits shall be
credited to subsequent payments to be made for such items. If an Event of
Default, as herein defined, shall occur under the terms of this Mortgage, the
Loan Agreement, or the Note, Mortgagee may, at its option, without being
required to do so, apply any deposits on hand to the Indebtedness in such order
and manner as Mortgagee may elect. When the Indebtedness has been fully paid any
remaining deposits shall be returned to Mortgagor or other person entitled
thereto. All deposits are hereby pledged as additional security for the
Indebtedness and shall be held for the purposes for which made as herein
provided. Such deposits may be held by Mortgagee, or its agent, and shall be
held without any allowance of interest thereon and shall not be subject to the
decision or control of Mortgagor. The enforceability of the covenants relating
to taxes and assessments provided in

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Section 1.08 hereof and the payment of premiums for insurance provided in
Section 2.01 hereof shall not be affected except insofar as those obligations
have been met by compliance with this Section. Mortgagee may from time to time,
at its option, waive, and after such waiver, reinstate any and all of the
provisions contained in this Section. While such waiver is in effect, Mortgagor
shall pay taxes and assessments and premiums for insurance as herein provided.

                                   ARTICLE III

                       APPLICATION OF INSURANCE AND AWARDS

         Section 3.01. Damage to or Destruction of the Mortgaged Property.
Mortgagor shall give Mortgagee prompt notice of any damage to or destruction of
the Mortgaged Property or any part thereof (each such occurrence of damage or
destruction shall be known as a separate and distinct "Casualty"), and in case
of loss covered by policies of insurance, Mortgagee and Mortgagor jointly shall
settle and adjust any claim arising out of such policies and collect and receipt
for the proceeds payable therefrom, provided, that Mortgagor may itself adjust
and collect for any losses arising out of a single occurrence aggregating not in
excess of $25,000. Any expense incurred by Mortgagee in the adjustment and
collection of insurance proceeds (including without limitation the cost of any
independent appraisal of the loss or damage on behalf of Mortgagee) shall be
reimbursed to Mortgagee first out of any proceeds.

         Section 3.02. Condemnation. Mortgagor shall give Mortgagee prompt
notice of any action, actual or threatened, in condemnation or eminent domain
and hereby assigns, transfers and sets over to Mortgagee the entire proceeds of
any award or claim for damages for all or any part of the Mortgaged Property
taken or damaged under the power of eminent domain or condemnation. Mortgagee is
hereby authorized to intervene in any such action in the name of Mortgagor, to
compromise and settle any such action or claim, and to collect and receive from
the condemning authorities and give proper receipts and acquittances for such
proceeds. Any expenses incurred by Mortgagee in intervening in such action or
compromising and settling such action or claim, or collecting such proceeds
shall be reimbursed to Mortgagee first out of the proceeds.

         Section 3.03. Disbursement of Insurance and Condemnation Proceeds. If
(i) in the sole opinion of Mortgagee, the proceeds from any insurance claim or
condemnation award received pursuant to Section 3.01 or 3.02 (after payment of
expenses as contemplated by such Sections), together with any monies deposited
by Mortgagee with Mortgagor for the purposes of restoration or repair as
hereinafter set forth are sufficient to repair and restore the Mortgaged
Property to substantially the same condition as existed immediately prior to
such damage, destruction or condemnation, and (ii) Mortgagor is not then in
default under the Note, the Loan Agreement or this Mortgage, and (iii) such
repair or restoration shall not result in the creation of any lien or
encumbrance on the Mortgaged Property, other than Permitted Encumbrances, and
(iv) Mortgagor pays Mortgagee's expenses in connection with the foregoing, and
(v) the Casualty occurs at least twelve (12) months prior to the expiration of
the Note, then Mortgagor shall have the right to use such proceeds to repair and
restore the Mortgaged Property; provided, however, that Mortgagee shall have the
right to approve (which approval shall not be unreasonably withheld) the plans
for such repair and restoration. In the event that any insurance or condemnation
proceeds are so applied to the restoration or repair of the Mortgaged Property,
the restoration or repair shall be done under the

                                      -8-

<PAGE>

supervision of an architect acceptable to Mortgagee and pursuant to plans and
specifications approved by Mortgagee and subject to such other terms,
provisions, requirements, safeguards and disbursement procedures as Mortgagee
may require. In such case the proceeds shall be held by Mortgagee for such
purposes and will from time to time be disbursed by Mortgagee to defray the
costs of such restoration or repair under such safeguards and controls as
Mortgagee may require to assure completion in accordance with the approved plans
and specifications and free of liens or claims. Any insurance or condemnation
proceeds which are not applied to repair or restoration of the Mortgaged
Property and any surplus which may remain after payment of all costs of
restoration or repair may at the option of Mortgagee be applied to reduction of
that portion of the Indebtedness then most remotely to be paid, whether due or
not, or returned to Mortgagor or other person entitled thereto, the choice of
application to be solely at the discretion of Mortgagee.

                                   ARTICLE IV

                                LEASES AND RENTS

         Section 4.01. Mortgagor to Comply with Leases. Mortgagor shall, at its
own cost and expense, (a) perform, comply with and discharge all of the
obligations of Mortgagor under any leases or agreements for the use of the
Mortgaged Property or any part thereof, (b) use its best efforts to enforce or
secure the performance of each obligation and understanding of the respective
tenants under any such leases, and (c) appear in and defend, any action or
proceeding arising out of or in any manner connected with Mortgagor's interest
in any leases of the Mortgaged Property or any part thereof. Mortgagor shall
permit neither surrender nor assignment of any tenant's interest under said
leases unless the right to assign or surrender is expressly reserved under the
lease. Mortgagor shall not anticipate any installment of rent for more than one
(1) month in advance of its due date, nor execute any mortgage or create or
permit a lien which may be or become superior to any such leases, nor permit a
subordination of any lease to such mortgage or lien. Mortgagor shall not modify
or amend the terms of any such leases, nor borrow against or pledge the rentals
from such neither leases nor exercise or waive any default of the tenant
thereunder without the prior written consent of the Mortgagee.

         Section 4.02. Mortgagee's Right to Perform Under Leases. In the event
Mortgagor fails to perform, comply with or discharge any obligations of
Mortgagor under any lease or should Mortgagee become aware of or be notified by
any tenant under any lease of a failure on the part of Mortgagor to so perform,
comply with or discharge its obligations under said lease, Mortgagee may, but
shall not be obligated to, and without demand upon Mortgagor, and without
waiving or releasing Mortgagor from any obligation contained in this Mortgage,
remedy such failure. Mortgagor shall pay to Mortgagee upon demand all sums
incurred by Mortgagee in remedying any such failure together with interest from
the date of advance by Mortgagee at the rate equal to that as specified in the
Note. No such advance shall be deemed to relieve Mortgagor from any default
hereunder.

         Section 4.03. Assignment of Leases and Rents. As additional security
for the payment of the Indebtedness, Mortgagor does hereby bargain, sell, assign
and transfer unto Mortgagee, its successors and assigns, all of the leases which
now or hereafter may affect the Mortgaged Property, or any part thereof, during
the term of this Mortgage and all of the rents, profits, and other income of any
kind now due and which may hereafter become due under or by virtue of any lease
or agreement, whether written or verbal, for the use or occupancy of the
Mortgaged Property, or any

                                      -9-

<PAGE>

part thereof, whether presently existing or entered into at any time during the
term of this Mortgage, whether before or after foreclosure or during the period
of redemption. It is the expressed intention of Mortgagor and Mortgagee to
establish an absolute transfer and assignment of all such leases and agreements
and all of the rents, profits and other income of any kind from the Mortgaged
Property unto Mortgagee, its successors and assigns, and Mortgagor does hereby
appoint irrevocably Mortgagee its true and lawful attorney in its name and
stead, which appointment is coupled with an interest, to collect all of said
rents, profits and other income; provided that, unless and until an Event of
Default, as herein defined, occurs under this Mortgage, Mortgagor shall have the
right to collect and retain said rents, profits and other income. The assignment
of rents shall be effective until the payment of all money secured by this
Mortgage, or in the event of foreclosure, until the period of redemption
expires. Regardless of the extinguishment of the debt by a foreclosure sale,
this benefit shall continue for the benefit of the purchaser at such sale.

         The entering upon and taking possession of the Mortgaged Property and
the collection of such rents, profits and other income shall not cure or waive
any defaults under this Mortgage nor in any way operate to prevent Mortgagee
from pursuing any other remedy which it may now or hereafter have under the
terms of this Mortgage nor shall it in any way be deemed to constitute Mortgagee
a mortgagee-in-possession.

                                    ARTICLE V

                             UNIFORM COMMERCIAL CODE

         Section 5.01. Security Agreement; Fixture Filing. This Mortgage shall
constitute a security agreement as defined in the Minnesota Uniform Commercial
Code and all acts amendatory thereof and any similar or replacement statute
hereafter enacted (the "Code"), and as to those items of Personal Property
described in this Mortgage that are, or are to become fixtures related to the
real estate mortgaged herein, it is intended as to those items that this
Mortgage shall be effective as a financing statement filed as a fixture filing
from the date of its filing in the real estate records of the County where the
Mortgaged Property is situate. A photographic or other reproduction of this
Mortgage may also be filed as a financing statement. The name of the record
owner of said real estate is the Mortgagor as set forth in page one of this
Mortgage. Information concerning the security interest created by this
instrument may be obtained from Mortgagee, as secured party, at its address as
set forth in page one of this Mortgage. The address of Mortgagor, as debtor, is
as set forth in page one of this Mortgage. This document covers goods which are
or are to become fixtures and other personal property.

                                   ARTICLE VI

                           CERTAIN RIGHTS OF MORTGAGEE

         Section 6.01 Right to Cure Default. If Mortgagor shall fail to comply
with any of the terms, covenants, agreements or conditions of this Mortgage, the
Note, the Loan Agreement or the other Loan Documents (as defined in the Loan
Agreement), Mortgagee may, but shall not be obligated to, without demand upon
Mortgagor, and without waiving or releasing Mortgagor from any obligation in
this Mortgage or in the Loan Agreement contained, remedy such failure, and
Mortgagor agrees to pay upon demand all sums incurred and the cost of
performance by Mortgagee in remedying any such failure together with interest on
all such sums and the costs of such performance from the date

                                      -10-

<PAGE>

of such advance and performance at the rate equal to that specified in the Note.
All such sums and costs, together with interest as aforesaid, shall constitute a
portion of the Indebtedness, but no such advance or performance shall be deemed
to relieve Mortgagor from any failure hereunder.

         Section 6.02 Inspection. Mortgagor shall permit Mortgagee's authorized
representatives to enter the Mortgaged Property at all reasonable times for the
purpose of inspecting the same; however, Mortgagee shall have no duty to make
such inspections and shall not incur any liability or obligation for making or
not making any such inspections.

         Section 6.03 Waivers; Releases; Resort to Other Security. Without
affecting the liability of Mortgagor for payment of the Indebtedness or
performance of any obligation contained herein, and without affecting the rights
of Mortgagee with respect to any security not expressly released in writing,
Mortgagee may, at any time, and without notice to or the consent of Mortgagor
(a) make any agreement extending the time or otherwise altering the terms of
payment of all or any part of the Indebtedness or modifying or waiving any
obligation, or subordinating, modifying or otherwise dealing with the lien or
charge hereof, (b) accept any additional security, (c) release or otherwise deal
with any property, real or personal, including any or all of the Mortgaged
Property, including making partial releases of the Mortgaged Property; or (d)
resort to any security agreements, pledges, contracts of guarantee, assignments
of rents and leases or other securities, and exhaust any one or more of said
securities and the security hereunder, either concurrently or independently and
in such order as it may determine.

         Section 6.04 Rights Cumulative. Each right, power or remedy herein
conferred upon Mortgagee is cumulative and in addition to every other right,
power or remedy, express or implied, now or hereafter arising, available to
Mortgagee, at law or in equity, or under the Code, or under any other agreement,
and each and every right, power and remedy herein set forth or otherwise so
existing may be exercised from time to time as often and in such order as may be
deemed expedient by Mortgagee and shall not be a waiver of the right to exercise
at any time thereafter any other right, power or remedy. No delay or omission by
Mortgagee in the exercise of any right, power or remedy arising hereunder or
arising otherwise shall impair any such right, power or remedy or the right of
Mortgagee to resort thereto at a later date or be construed to be a waiver of
any default or Event of Default, as herein defined, under this Mortgage, the
Note, the Loan Agreement or any other Loan Document.

         Section 6.05 Subsequent Agreements. Any agreement hereafter made by
Mortgagor and Mortgagee pursuant to this Mortgage shall be superior to the
rights of the holder of any intervening lien or encumbrance.

         Section 6.06 Waiver of Appraisement, Marshaling. Mortgagor hereby
waives to the full extent lawfully allowed the benefit of any appraisement,
evaluation, stay and extension laws now or hereinafter in force. Mortgagor
hereby waives any rights available with respect to marshaling of assets and
Mortgagee shall not be required to separately sell any portion of the Mortgaged
Property, and Mortgagee shall not be required to exhaust its remedies against a
specific portion of the Mortgaged Property before proceeding against the other.
Mortgagor does hereby expressly consent to and authorize the sale of the
Mortgaged Property or any part thereof as a single unit or parcel or in such
other manner as Mortgagee may determine.

                                      -11-

<PAGE>

                                   ARTICLE VII

                         EVENTS OF DEFAULT AND REMEDIES

         Section 7.01 Events of Default. An "Event of Default" as defined in the
Loan Agreement shall constitute an "Event of Default" under this Mortgage.

         Section 7.02 Certain Remedies; Acceleration, Prepayment Premium and
Foreclosure. If an Event of Default shall occur, Mortgagee may immediately
declare the entire unpaid principal balance of the Note together with all other
portions of the Indebtedness to be immediately due and payable and thereupon all
such unpaid principal balance of the Note together with all accrued interest
thereon, prepayment premium and all other portions of the Indebtedness secured
hereby shall be and become immediately due and payable. If an Event of Default
shall occur, then in every such case Mortgagee may (a) proceed to protect and
enforce its rights by a suit or suits in equity or at law, either for the
specific performance of any term, covenant, agreement or condition contained
herein or in the Note or in the Loan Agreement or in any other Loan Document, or
in aid of the execution of any power herein or therein granted for collection of
the Note or the Indebtedness or for the foreclosure of this Mortgage, or for the
enforcement of any other appropriate legal or equitable remedy, and/or (b)
foreclose this Mortgage; and Mortgagor hereby authorizes and fully empowers
Mortgagee to foreclose the lien of this Mortgage in the manner prescribed by
applicable law, and out of the proceeds arising from sale and foreclosure to
retain the principal of the Note and interest on the Note and all other portions
of the Indebtedness together with all such sums of money as Mortgagee shall have
expended or advanced pursuant to this Mortgage or pursuant to statute together
with interest thereon as herein provided and all costs and expenses of such
foreclosure, including lawful attorneys' fees, with the balance, if any, to be
paid to the persons entitled thereto by law. In case of any sale of the
Mortgaged Property, or any part thereof, pursuant to any judgment or decree of
any court or otherwise in connection with the enforcement of any of the terms of
this Mortgage, Mortgagee may become the purchaser, and for the purpose of making
settlement for or payment of the purchase price, shall be entitled to deliver
and use the Note and any claims for interest and prepayment premium matured and
unpaid thereon, together with all other portions of the Indebtedness, in order
that there may be credited as paid on the purchase price the sum then due under
the Note, including the principal of the Note and prepayment premium and
interest thereof and all other portions of the Indebtedness.

         Section 7.03 Receiver. If an Event of Default shall occur hereunder, it
is further covenanted and agreed that if at any time in the opinion of Mortgagee
a receivership may be necessary to protect the Mortgaged Property, whether
before or after maturity of the Indebtedness or at the time of or after the
institution of suit to collect the Indebtedness, or to enforce this Mortgage,
Mortgagee shall, as a matter of strict right and regardless of the value of the
mortgage security for the amounts due hereunder or secured hereby, or of the
solvency of any party bound for the payment of the Indebtedness, have the right
to the appointment on ex parte application, and without notice to anyone, by any
Court having jurisdiction, of a receiver to take charge of, manage, preserve,
protect, operate the Mortgaged Property and to collect the rents, to make all
necessary and needed repairs, and to pay all taxes and assessments against the
Mortgaged Property and insurance premiums for insurance thereon and after the
payment of the expenses of the receivership and management of the Mortgaged
Property to apply the net proceeds in reduction of the Indebtedness hereby
secured or in such manner as the Court shall direct. Such receivership shall, at
the option of Mortgagee, continue

                                      -12-

<PAGE>

until full payment of all sums hereby secured, or until title to said Mortgaged
Property shall have passed by sale under this Mortgage, as further provided in
any assignment of rents executed by Mortgagor to Mortgagee (whether contained in
this Mortgage or in a separate instrument).

         Section 7.04 Rights Under Uniform Commercial Code. In addition to the
rights available to a mortgagee of real property, Mortgagee shall also have all
the rights, remedies and recourse available to a secured party under the Code
including the right to proceed under the provisions of the Code governing
default as to any Collateral which may be included in the Mortgaged Property or
which may be deemed non-realty in a foreclosure of this Mortgage or to proceed
as to such Collateral in accordance with the procedures and remedies available
pursuant to a foreclosure of real estate.

         Section 7.05 Right to Discontinue Proceeding. In the event Mortgagee
shall have proceeded to invoke any right, remedy or recourse permitted under
this Mortgage and shall thereafter elect to discontinue or abandon the same for
any reason, Mortgagee shall have the unqualified right to do so and in such
event Mortgagor and Mortgagee shall be restored to their former positions with
respect to the Indebtedness. This Mortgage, the Mortgaged Property and all
rights, remedies and recourse of Mortgagee shall continue as if the same had not
been invoked.

         Section 7.06 Acknowledgment of Waiver of Hearing Before Sale. Mortgagor
understands and agrees that if an Event of Default occurs under the terms of
this Mortgage, Mortgagee has the right, inter alia, to foreclose this Mortgage
by advertisement in accordance with applicable law. Mortgagor further
understands that in the event of such default Mortgagee may also elect its
rights under the Code and take possession of the Collateral, or any part
thereof, and dispose of the same by sale or otherwise in one or more parcels
provided that at least ten (10) days' prior notice of such disposition must be
given, all as provided for by the Code, as hereafter amended or by any similar
or replacement statute hereafter enacted. MORTGAGOR HEREBY RELINQUISHES, WAIVES
AND GIVES UP ANY CONSTITUTIONAL RIGHTS IT MAY HAVE TO NOTICE AND HEARING EXCEPT
AS PROVIDED HEREIN BEFORE SALE OF THE MORTGAGED PROPERTY AND EXPRESSLY CONSENTS
AND AGREES THAT THE MORTGAGED PROPERTY MAY BE FORECLOSED BY ADVERTISEMENT AND
THAT THE COLLATERAL MAY BE DISPOSED OR PURSUANT TO THE CODE, ALL AS DESCRIBED
ABOVE. MORTGAGOR ACKNOWLEDGES THAT IT IS REPRESENTED BY LEGAL COUNSEL; THAT
BEFORE SIGNING THIS DOCUMENT THIS SECTION AND MORTGAGOR'S CONSTITUTIONAL RIGHTS
WERE FULLY EXPLAINED BY SUCH COUNSEL AND THAT MORTGAGOR UNDERSTANDS THE NATURE
AND EXTENT OF THE RIGHTS WAIVED HEREBY AND THE EFFECT OF SUCH WAIVER.

                                  ARTICLE VIII

                            ENVIRONMENTAL PROVISIONS

         Section 8.01 Environmental Concerns.

                  (a) To the best of Mortgagor's knowledge, after the
         investigation performed in accordance with the letter attached hereto
         as Exhibit C and made a part hereof, the Mortgaged Property, has never
         been used by previous owners and/or operators to refine, produce,
         store, handle, transfer, process or transport "Hazardous Substances",
         as such term is defined by

                                      -13-

<PAGE>

         applicable federal law, except in compliance with applicable laws, and
         the Mortgagor has not in the past, nor does Mortgagor intend in the
         future, to use the Mortgaged Property, for the purpose of refining,
         producing, storing, handling, transferring, processing or transporting
         said "Hazardous Substances", except in compliance with applicable laws.

                  (b) Mortgagor has not received a summons, citation, directive,
         letter or other communication, written or oral, from any applicable
         governmental agency concerning any intentional or unintentional action
         or omission on Mortgagor's part resulting in the releasing, spilling,
         leaking, pumping, pouring, emitting, emptying or dumping of Hazardous
         Substances into the waters or onto the lands of the State, or into the
         waters outside the jurisdiction of the State resulting in damage to the
         lands, waters, fish, shellfish, wildlife, biota, air and other
         resources owned, managed, held in trust or otherwise controlled by the
         State.

                  (c) Mortgagor shall operate the Mortgaged Property or cause it
         to be operated in material compliance with all applicable rules and
         regulations promulgated by all applicable governmental environmental
         authorities and agencies. Mortgagor shall have the right in good faith
         to contest or appeal from such laws, ordinances and regulations and any
         decision adverse to the Mortgagor based thereon, but all costs, fees
         and expenses incurred in connection with such proceedings shall be
         borne by the Mortgagor.

                  (d) Mortgagor shall not cause or permit to exist, as a result
         of an action or omission on its part, a releasing, spilling, leaking,
         pumping, emitting, pouring, emptying or dumping of a Hazardous
         Substance into waters of the State or onto the lands from which it
         might flow or drain into said waters, or into waters outside the
         jurisdiction of the State where damage may result to the lands, waters,
         fish, shellfish, wildlife, biota, air and other resources owned,
         managed, held in trust or otherwise controlled by the State, unless
         said release, spill, leak, pumping, emitting, pouring, emptying or
         dumping is pursuant to and in compliance with the conditions of a
         permit issued by the appropriate federal or state governmental
         authorities or other applicable laws.

                  (e) Should Mortgagor cause or permit any action or omission
         resulting in the releasing, spilling, leaking, pumping, pouring,
         emitting, emptying or dumping of Hazardous Substances into the waters
         or onto the lands of the State, or into the waters outside the
         jurisdiction of the State, resulting in damage to the lands, waters,
         fish, shellfish, wildlife, biota, air or other resources owned, managed
         or held in trust or otherwise controlled by the State, without having
         obtained a permit issued by the appropriate governmental authorities,
         Mortgagor shall promptly clean up the same in accordance with the
         provisions of applicable State or Federal law.

                  (f) Notwithstanding anything in this Article VIII to the
         contrary, Mortgagor may store and use on the Mortgaged Property
         supplies which are used in the normal course of Mortgagor's business.
         Mortgagor covenants and agrees that it will use and dispose of all such
         supplies in compliance with all applicable laws and regulations.

                                      -14-

<PAGE>

                                   ARTICLE IX

                                  MISCELLANEOUS

         Section 9.01 Applicable Law. This Mortgage shall be interpreted,
construed and enforced according to the laws of the State of Minnesota.

         Section 9.02 No Implied Waiver. Any delay by Mortgagee in exercising or
any failure by Mortgagee to exercise any right or remedy hereunder or afforded
by law shall not be a waiver of nor preclude the exercise of any right or remedy
hereunder, whether on such occasion or any future occasion.

         Section 9.03 Successors and Assigns. This Mortgage and each and every
term, covenant, agreement, condition and other provision hereof shall be binding
upon Mortgagor and its successors and assigns including without limitation each
and every from time to time record owner of the Mortgaged Property or any other
person having an interest therein, shall run with the land and shall inure to
the benefit of Mortgagee and its successors and assigns. As used herein the
words "successors and assigns" shall also be deemed to include the heirs,
representatives, administrators and executors of any natural person who is a
party to this Mortgage.

         Section 9.04 Notices. Any notice which any party hereto may desire or
may be required to give to any other party shall be in writing and the mailing
thereof by certified mail to their respective addresses as set forth in page one
of this Mortgage, or to such other places any party hereto may hereafter by
notice in writing designate, shall constitute service of notice hereunder.

         Section 9.05 Captions and Headings. The captions and headings of the
various sections of this Mortgage are for convenience only and are not to be
construed as confining or limiting in any way the scope or intent of the
provisions hereof.

         Section 9.06 Severability and Survival. The unenforceability or
invalidity of any provision or provisions hereof shall not render any other
provision or provisions herein contained unenforceable or invalid, and all
provisions hereof, in all other respects, shall remain valid and enforceable.

         IN WITNESS WHEREOF, Mortgagor has caused these presents to be executed
as of the date first above written.

                                           HEI, INC.

                                           By:  /s/ DOUGLAS NESBIT
                                               ---------------------------------
                                               Its: Chief Financial Officer
                                                   -----------------------------


                                      -15-

<PAGE>

STATE OF MINNESOTA        )
                          ) ss:
COUNTY OF HENNEPIN        )

         The foregoing instrument was acknowledged before me this 14th day of
October, 2003, by Douglas J. Nesbit, the Chief Financial Officer of HEI, Inc.,
on behalf of the corporation. My Commission expires on January 31, 2005.

                                                /s/ MARY JOEL MAKEPEACE
                                                -----------------------------
                                                Notary Public

This instrument prepared by:
COMMERCE FINANCIAL GROUP, INC.
7650 Edinborough Way, Suite 160
Edina, MN  55435

                                      -16-