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                                 EXHIBIT 10.18

                         MARVIN KANTOR NOTE/COLLATERAL

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                            DEMAND BUSINESS LOAN NOTE


$300,000.00                               DATE: EFFECTIVE AS OF FEBRUARY 1, 1999


      PROMISE TO PAY: For value received, the undersigned, WENDT-BRISTOL HEALTH
SERVICES CORPORATION, a Delaware corporation (the "Borrower"), promises to pay
to the order of MARVIN D. KANTOR (the "Lender"), at 1000 Urlin Avenue, Columbus,
Ohio 43212 (or such other address as the Lender shall give notice of to the
Borrower), the sum of Three Hundred Thousand Dollars ($300,000.00), plus
interest computed on the basis of the actual number of days elapsed in a year of
365/366 days at the rate of eight percent (8%) per annum (the "Note Rate") on
the principal amount outstanding from time to time, whether by acceleration or
otherwise, and, upon the occurrence of an Event of Default hereunder and during
the continuance of such, the interest rate per annum shall be 100 basis points
above the Note Rate. Interest shall be payable quarterly on a calendar year
basis.

      In no event shall the interest rate exceed the maximum rate allowed by
law; any interest payment which would for any reason be deemed unlawful under
applicable law shall be applied to principal.

      Principal shall be due and payable on demand. This Note is a demand Note
due and owing immediately upon demand by Lender. Immediate action to enforce its
payment may be taken at any time, without notice and without reason.

      This Note is a revolving credit subject to the terms of this paragraph.
Subject to the conditions hereof and of any other agreement between the parties
relating hereto and until demand, the undersigned may borrow and re-borrow from
the Lender and the Lender may, in its sole discretion, lend and re-lend to the
undersigned such amounts not to exceed Three Hundred Thousand Dollars
($300,000.00) as the undersigned may at any time and from time to time request
upon satisfactory notice to the Lender.

      The Borrower may at any time prepay this Note, in whole or in part,
without premium or penalty, together with accrued interest on the amount of any
such prepayment.

      SECURITY: To secure the payment of this Note, the Borrower has executed
and delivered to the Lender a certain Stock Pledge Agreement dated effective as
of February 1, 1999.

      RELATED DOCUMENTS: The terms of any other documents executed as part of
the loan evidenced by this Note are incorporated herein by reference.

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                         ADDITIONAL TERMS AND CONDITIONS

      EVENTS OF DEFAULT: If any of the following events occurs:

      1. The Borrower fails to timely pay any amount payable under this Note;

      2. The Borrower (a) fails to observe or perform any other term of this
Note; (b) fails to observe or perform any term of the Pledge Agreement; (c)
makes any materially incorrect or misleading representation, warranty, or
certificate to the Lender; or (d) makes any materially incorrect or misleading
representation in any financial statement or other information delivered to the
Lender;

      3. The Borrower (a) makes an assignment for the benefit of creditors; (b)
consents to the appointment of a custodian, receiver or trustee for itself or
for a substantial part of its assets; or (c) commences or consents to any
proceeding under any bankruptcy, reorganization, liquidation, insolvency or
similar laws of any jurisdiction;

      4. A custodian, receiver or trustee is appointed for the Borrower or for a
substantial part of its assets without its consent and is not removed within
sixty (60) days after such appointment; or

      5. Proceedings are commenced against the Borrower under any bankruptcy,
reorganization, liquidation or similar laws of any jurisdiction, and such
proceedings remain undismissed for sixty (60) days after commencement; or the
Borrower consents to the commencement of those proceedings;

then this Note shall become due immediately, without notice, at the Lender's
option.

      REMEDIES: If this Note is not paid at maturity, whether by acceleration or
otherwise, the Lender shall have all of the rights and remedies provided by any
law or agreement. The Borrower is liable to the Lender for all reasonable costs
and expenses of every kind incurred in the making or collection of this Note,
including, without limitation, reasonable attorneys' fees and court costs. These
costs and expenses shall include, without limitation, any costs or expenses
incurred by the Lender in any bankruptcy, reorganization, insolvency or other
similar proceeding.

      WAIVER: Each endorser and any other party liable on this Note severally
waives demand, presentment, notice of dishonor and protest, and consents to any
extension or postponement of time of its payment without limit as to the number
or period, to any substitution, exchange or release of all or part of the
collateral securing this Note, to the addition of any party, and to the release
or discharge of, or suspension of any rights and remedies against, any person
who may be liable for the payment of this Note. No delay on the part of the
Lender in the exercise of any right or remedy shall operate as a waiver. No
single or partial exercise by the Lender of any right or remedy shall preclude
any other future exercise of it or the exercise of any other right or remedy.


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No waiver or indulgence by the Lender of any default shall be effective unless
in writing and signed by the Lender, nor shall a waiver on one occasion be
construed as a bar to or waiver of that right on any future occasion.

      MISCELLANEOUS This Note shall be binding on the Borrower and its
successors, and shall inure to the benefit of the Lender, its successors and
assigns. Any reference to the Lender shall include any holder of this Note. This
Note is delivered in the State of Ohio and governed by Ohio law. Section
headings are for convenience of reference only and shall not affect the
interpretation of this Note. This Note and all related loan documents embody the
entire agreement between the Borrower and the Lender regarding the terms of the
loan evidenced by this Note, and supersede all oral statements and prior
writings relating to that loan. Any provision of this Note which is prohibited
or unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

      CONFESSION OF JUDGMENT: The Borrower irrevocably authorizes any
attorney-at-law, including any attorney-at-law employed or retained by the
Lender, to appear for the Borrower in any court of record in Franklin County,
Ohio (which the Borrower acknowledges to be the place where this Note was made),
or any other state or jurisdiction wherein the Borrower may then reside, to (i)
waive the issuing and service of process; (ii) confess judgment against the
Borrower in favor of the holder of this Note for the amount then due, together
with costs of suit; (iii) release all errors; and (iv) waive all rights of
appeal. The Borrower consents to the jurisdiction and venue of that court. The
Borrower waives any conflict of interest that any attorney-at-law, including any
attorney-at-law employed or retained by the Lender, may have in confessing
judgment hereunder and consents to the payment of a legal fee to any
attorney-at-law confessing judgment hereunder.

WARNING - BY SIGNING THIS PAPER YOU GIVE UP YOUR RIGHT TO NOTICE AND COURT
TRIAL. IF YOU DO NOT PAY ON TIME A COURT JUDGMENT MAY BE TAKEN AGAINST YOU
WITHOUT YOUR PRIOR KNOWLEDGE AND THE POWERS OF A COURT CAN BE USED TO COLLECT
FROM YOU REGARDLESS OF ANY CLAIMS YOU MAY HAVE AGAINST THE CREDITOR WHETHER FOR
RETURNED GOODS, FAULTY GOODS, FAILURE ON HIS PART TO COMPLY WITH THE AGREEMENT,
OR ANY OTHER CAUSE.


                                       WENDT-BRISTOL HEALTH
                                       SERVICES CORPORATION


                                       BY:
                                          -----------------------------------
                                          SHELDON A. GOLD, PRESIDENT



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                             STOCK PLEDGE AGREEMENT

         THIS STOCK PLEDGE AGREEMENT (the "Agreement") is made effective as of
February 1, 1999 by WENDT-BRISTOL HEALTH SERVICES CORPORATION, (the "Borrower"),
in favor of MARVIN D. KANTOR, (the "Lender").

                             BACKGROUND INFORMATION

         A. Borrower is the owner of 1,017,560 shares of the capital stock of
Wendt-Bristol Diagnostics Company, an Ohio corporation ("W-BDC"), evidenced by
the following Certificates:

                  CERTIFICATE           NUMBER OF
                     NUMBER              SHARES

                      D 0050             437,675
                      D 0051              20,000
                    WBD 0287              10,000
                    WBD 0326                 400
                    WBD 0332             172,685
                    WBD 0335             300,000
                    WBD 0351                 600
                    WBD 0356               1,000
                    WBD 0397               1,200
                    WBD 0409              25,000
                    WBD 0413              45,000
                    WBD 0431               4,000
                                       ---------
                             TOTAL     1,017,560

         B. Lender, in the past has agreed to continue to make loans to Borrower
in the aggregate principal amount of $300,000 (the "Loan"), which Loan is
evidenced by a revolving Demand Business Loan Note payable to the order of
Lender executed by Borrower, dated effective as of February 1, 1999 (the
"Note").

         C. The execution of this Agreement and the delivery of the Pledged
Stock (as defined below) to Lender are conditions precedent to Lender's
obligation to make the Loan.

                                   PROVISIONS

         NOW, THEREFORE, in consideration of the foregoing, in order to induce
Lender to make the Loan and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, Borrower hereby agrees
with Lender as follows:

         SECTION 1. DEFINED TERMS. For purposes of this Agreement, in addition
to the terms defined elsewhere in this Agreement, the following terms shall have
the meanings set forth below:
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         "Collateral" shall mean all property (whether described herein or not)
at any time pledged or required to be pledged to Lender hereunder, including the
Pledged Stock, and all payments to be made by W-BDC pursuant thereto, income
therefrom and proceeds thereof.

         "Pledged Stock" shall mean the 1,017,560 shares of the capital stock of
W-BDC owned by Borrower and evidenced by Certificate Nos. D 0050, D 0051, WBD
0287, WBD 0326, WBD 0332, WBD 0335, WBD 0351, WBD 0356, WBD 0397, WBD 0409, WBD
0413 and WBD 0431 as more fully set forth in Background Information, Paragraph B
above which is hereby incorporated by reference herein, together with all
shares, certificates, options, rights or other distributions issued as an
addition to, in substitution or in exchange for, or on account of, any such
shares, and all proceeds of all the foregoing, now or hereafter owned or
acquired by Borrower.

         SECTION 2. PLEDGE.

         (a) Borrower hereby pledges, assigns, hypothecates, transfers and
delivers to Lender the Pledged Stock and agrees to pledge all additional shares
of capital stock of W-BDC that Borrower may hereafter acquire with respect
thereto; and grants to Lender a first lien on and security interest in (i) the
Pledged Stock; (ii) all certificates, shares, notes, obligations, distributions,
securities and other property issued or delivered from time to time in lieu of
or in substitution for or with respect to the Pledged Stock; (iii) all present
and future security and collateral for any of the foregoing; and (iv) all
payments or other proceeds under or with respect to any of the foregoing, as
collateral security for the due and punctual payment and performance by Borrower
of all its obligations and liabilities, absolute or contingent, liquidated or
unliquidated, now existing or hereinafter incurred under, arising out of and in
connection with the Loan and the Note, whether for principal, interest, fees,
costs, expenses or otherwise (all the foregoing being hereinafter called the
"Obligations").

         (b) Borrower shall deliver to Lender the certificate(s) for the Pledged
Stock and a stock transfer power(s) duly endorsed in blank simultaneously
herewith, in form and substances satisfactory to Lender.

         (c) So long as no Event of Default (as defined in Section 5 hereof)
shall have occurred and be continuing at any time, Borrower shall have the right
to exercise all voting rights, and to receive and retain all cash dividends and
other cash payments, with respect to the Pledged Stock. Upon the occurrence of,
and during the continuation of, an Event of Default, Lender, at Lender's option,
may (i) receive any such cash dividends and other cash payments, and (ii) have
any part or all of the Pledged Stock registered in its name or that of its
nominee, and Borrower hereby covenants that, upon Lender's request, Borrower
will cause W-BDC, the transfer agent or registrar of the Pledged Stock to effect
such registration. Immediately and without further notice, upon the occurrence
of, and during the continuance of, an Event of Default, whether or not the
Pledged Stock shall have been registered in the name of Lender or its nominee,
Lender or its nominee shall have, with respect to the Pledged Stock, the right
to exercise all voting rights as to

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the Pledged Stock, all other corporate rights and all conversion, exchange,
subscription or other rights, privileges or options pertaining thereto as if it
were the absolute owner thereof, including, without limitation, the right to
exchange any or all of the Pledged Stock upon the merger, consolidation,
reorganization, recapitalization or other readjustment of the issuer thereof, or
upon the exercise by such issuer of any right, privilege or option pertaining to
any of the Pledged Stock, and, in connection therewith, to deliver any of the
Pledged stock to any committee, depository, transfer agent, registrar or other
designated agency upon such terms and conditions as it may determine, all
without liability except to account for property actually received by it;
provided, however, that (i) Lender shall have no duty to exercise any of the
aforesaid rights, privileges or options and shall not be responsible for any
failure to do so or delay in so doing; and (ii) Lender may by written notice to
Borrower relinquish, either partially or completely in accordance with any terms
or conditions Lender may set forth in such notice, any or all voting rights
Lender may acquire pursuant to this Section 2(c).

         SECTION 3. NOTICE TO W-BDC. Within five (5) days after the execution of
this Agreement, Borrower shall give notice of the pledge of the Pledged Stock
pursuant to this Agreement to W-BDC, such notice to be in the form of the Notice
of Pledge attached hereto as Exhibit A.

         SECTION 4. DISTRIBUTIONS, ETC. If Borrower shall become entitled to
receive or shall receive, in connection with any of the Pledged Stock, any
Collateral, including, without limitation:

         (a) stock certificates, including, without limitation, any certificates
representing a stock dividend or issued in connection with any increase or
reduction of capital, reclassification, merger, consolidation, sale of assets,
combination of shares, stock split, spin-off or split-off;

         (b) options, warrants or rights, whether as an addition to, or in
substitution or in exchange for, any of the Pledged Stock, or otherwise; or

         (c) dividends or distributions payable in money (subject to the right
of Borrower to receive and retain such dividends and distributions in accordance
with Section 2(c) hereof) or other property, including securities issued by a
person other than W-BDC.

then Borrower shall accept the same as Lender's agent and hold the same in trust
on behalf of and for the benefit of Lender, segregated from the other assets of
Borrower and deliver the same forthwith to Lender, in the exact form received,
with the endorsement of Borrower when necessary and/or appropriate undated
powers, duly executed in blank, to be held by Lender, subject to the terms
hereof, as additional collateral security for the Obligations. Any sums paid
upon or in respect of the Pledged Stock or Collateral upon the liquidation or
dissolution of W-BDC shall be paid over to Lender, as additional collateral
security for the Obligations. All sums of money and property so paid or
distributed in respect of the Pledged Stock or other Collateral which is
received by Borrower shall, until paid or delivered to Lender, be held by
Borrower in

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trust, segregated from the other assets of Borrower, as additional collateral
security for the Obligations.

         SECTION 5. EVENTS OF DEFAULT; REMEDIES.

         (a) The occurrence of any of the following events shall constitute an
"Event of Default".

         (i)      Borrower shall default in the observance or performance of any
                  term, covenant or agreement contained herein; or

         (ii)     an Event of Default, as such term is defined in the Note shall
                  occur and be continuing after any applicable grace or cure
                  period.

         (b) Upon the occurrence and during the continuance of any Event of
Default, Lender, without demand of performance or other demand, advertisement or
notice of any kind (except the notice specified below of time and place of
public or private sale) to or upon Borrower or any other person (all and each of
which demands, advertisements and/or notices are hereby expressly waived), may
forthwith collect, receive, appropriate and realize upon the Collateral, or any
part thereof, and/or may forthwith sell, assign, give option or options to
purchase, contract to sell or otherwise dispose of and deliver said Collateral,
or any part thereof, in one or more parcels at public or private sale or sales,
at any exchange, broker's board or at Lender's offices or elsewhere. Lender
shall apply the net proceeds of any such collection, recovery, receipt
appropriation, realization or sale after deducting all reasonable costs and
expenses of every kind incurred therein or incidental to the care, safekeeping
or otherwise of any and all of the Collateral, including reasonable costs and
expenses of every kind incurred therein or incidental to the care, safekeeping
or otherwise of any and all of the Collateral, including reasonable attorneys'
fees and legal expenses, to the payment of the Obligations in such order as
Lender may elect, and only after so paying over such net proceeds and after the
payment by Lender of any other amount required by any provision of law. Borrower
agrees that, to the extent permitted by law, Lender need not give more than ten
(10) days' notice of the time and place of any public sale or of the time after
which a private sale or other intended disposition is to take place and that
such notice is reasonable notification of such matters. In addition to the
rights and remedies granted to it in this Agreement, the Note and in any other
instrument or agreement securing, evidencing or relating to any of the
Obligations, Lender shall have all the rights and remedies of a secured party
under the Uniform Commercial Code as adopted in the State of Ohio. All waivers
by Borrower of rights (including rights to notice) and all rights and remedies
afforded Borrower herein, and all other provisions of this Agreement, are
expressly made subject to any applicable mandatory provisions of law limiting,
or imposing conditions (including conditions as to reasonableness) upon, such
waivers or the effectiveness thereof or any such rights and remedies. Any sale
or other disposition of the Collateral shall be in compliance with all
provisions of the Uniform Commercial Code of the State of Ohio.

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         SECTION 6. REPRESENTATIONS AND WARRANTIES OF BORROWER. Borrower
represents and warrants that:

         (a) Borrower is the legal record and beneficial owner of the Pledged
Stock, subject to no pledge, lien, mortgage, hypothecation, security interest,
charge, option or other encumbrance whatsoever, except as created by this
Agreement;

         (b) Borrower has full power, authority and legal right to pledge, and
grant a security interest in, the Pledged Stock and the Collateral pursuant to
this Agreement; and

         (c) this Agreement has been duly executed and delivered by Borrower and
constitutes a legal, valid and binding obligation of Borrower.

         SECTION 7. COVENANTS OF BORROWER. Borrower covenants and agrees that:

         (a) Borrower will defend the right, title and security interest of
Lender in and to the Pledged Stock, the proceeds thereof and all other
Collateral against the claims and demands of all persons whomsoever;

         (b) Borrower will not sell, convey or otherwise dispose of any of the
Pledged Stock or any interest therein or create, incur or permit to exist any
pledge, mortgage, lien, charge, encumbrance or any security interest whatsoever
in, or with respect to, any of the Pledged Stock or the proceeds thereof, other
than that created hereby; and

         (c) Borrower will execute any and all documents reasonably requested by
Lender to continue, protect, perfect or otherwise defend Lender's interest in
and to the Collateral.

         SECTION 8. SEVERABILITY. Any provision of this Agreement which is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

         SECTION 9. NO WAIVER; CUMULATIVE REMEDIES. Lender shall not by any act,
delay, omission or otherwise be deemed to have waived any of its rights or
remedies hereunder and no waiver shall be valid unless in writing, signed by
Lender, and then only to the extent therein set forth. A waiver by Lender of any
right or remedy hereunder on any one occasion shall not be construed as a bar to
any right or remedy which Lender would otherwise have on any future occasion. No
failure to exercise, nor any delay in exercising on the part of Lender, any
right, power or privilege hereunder shall operate as a waiver thereof; nor shall
any single or partial exercise of any right, power or privilege hereunder
preclude any other or further exercise thereof or the exercise of any other
right, power or privilege. The rights and remedies herein provided

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are cumulative and may be exercised singly or concurrently, and are not
exclusive of any rights or remedies provided by law.

         SECTION 10. WAIVERS; AMENDMENTS. None of the terms or provisions of
this Agreement may be waived, altered, modified or amended except by an
instrument in writing, duly executed by Lender and Borrower. This Agreement and
all obligations of Borrower hereunder shall be binding upon Borrower's
successors and assigns, and shall, together with the rights and remedies of
Lender hereunder, inure to the benefit of Lender and its successors and assigns;
provided, that neither Borrower nor Lender may assign this Agreement without the
prior written consent of the other.

         SECTION 11. GOVERNING LAW. This Agreement shall be governed by, and be
construed and interpreted in accordance with, the laws of the State of Ohio
applicable to agreements executed, delivered and performed within such state.

         SECTION 12. NOTICES. Notices from one party to another relating to this
Agreement shall be deemed effective if made in writing (including
telecommunications) and delivered to the recipient's address, telex number or
facsimile number as set forth below by any of the following means: (a) hand
delivery; (b) registered or certified mail, postage prepaid, with return receipt
requested; (c) first class or express mail, postage prepaid; (d) Federal
Express, Purolator Courier or like overnight courier service; or (e) facsimile,
telex or other wire transmission with request for assurance of receipt in a
manner typical with respect to communications of that type. Notice made in
accordance with this section shall be deemed delivered on receipt if delivered
by hand or wire transmission, on the third business day after mailing if mailed
by first class, registered or certified mail or on the next business day after
mailing or deposit with an overnight courier service if delivered by express
mail or overnight courier

               If to Borrower:     Wendt-Bristol Health Services Corporation
                                   Attn: Sheldon A. Gold, President
                                   Two Nationwide Plaza
                                   280 North High Street, Suite 760
                                   Columbus, Ohio 43215

               If to Lender:       Marvin D. Kantor
                                   1000 Urlin Avenue, Apt. 919
                                   Columbus, Ohio 43212

         SECTION 13. CONTINUING SECURITY INTEREST. This Agreement shall create a
continuing security interest in the Collateral and shall (i) remain in full
force and effect until the indefeasible payment and satisfaction in full of all
Obligations, (ii) be binding upon Borrower and Borrower's successors and
assigns, and (iii) inure, together with the rights and remedies of Lender
hereunder, to the benefit of Lender and its successors, transferees and assigns.
Lender shall deliver to

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Borrower, upon termination of this Agreement, such of the Pledged Stock and
Collateral as shall not have been sold or otherwise disposed of pursuant to this
Agreement.

         IN WITNESS WHEREOF, Borrower has executed and delivered this Agreement,
effective as of February 1, 1999.


                                        BORROWER:

                                        WENDT-BRISTOL HEALTH SERVICES
                                        CORPORATION, A DELAWARE CORPORATION

                                   By:  /s/ Sheldon A. Gold
                                        -----------------------------------
                                        SHELDON A. GOLD, PRESIDENT

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