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                                                                   EXHIBIT 10(m)

                        SUPERCONDUCTIVE COMPONENTS, INC.
                        10% SUBORDINATED PROMISSORY NOTE

                                                                   March 1, 1993

     SUPERCONDUCTIVE COMPONENTS, INC., an Ohio corporation (the "Company"),
promises to pay to the order of Ingeborg V. Funk and Edward R. Funk, as tenants
in common, at 567 Welling Way, Worthington, Ohio 43085, the aggregate principal
sum of the advances listed on Schedule 1 as amended from time to time and
attached hereto and incorporated herein (the "Principal Sum"), together with
interest on the unpaid balance of the Principal Sum until paid at the rate of
ten percent (10%) per annum.

     Interest calculations shall be based on a 360-day year consisting of twelve
(12) thirty (30) day months and shall be based on the actual number of days
elapsed.

     1. PAYMENT.

        (a) Payment shall be made by wire transfer or in other immediately
available funds in lawful money of the United States of America to an account
specified by the holder.

        (b) Interest on the unpaid Principal Sum shall accrue through December
31, 1994, and such accrued interest plus the unpaid Principal Sum shall
constitute a new Principal Sum. Thereafter, this new Principal Sum, plus accrued
interest thereon, shall be due and payable in twelve (12) equal, consecutive,
quarterly installments commencing March 31, 1995 and continuing on the last day
of each quarter thereafter until the entire new Principal Sum, together with all
accrued and unpaid interest thereon, is paid in full.

        (c) This Note may be prepaid prior to maturity, at the option of the
Company, at any time without prepayment premium.

     2. SUBORDINATION OF NOTE.

        2.1 The indebtedness evidenced by this Note, including the Principal Sum
or the new Principal Sum, as the case may be, and interest thereon, shall be
subordinated and subject in right and payment, to the extent and in the manner
set forth in this Section 2 to the prior payment in full of all Senior
Indebtedness of the Company, as defined in Section 2.2 below, and each holder of
this Note, by his acceptance hereof, agrees to and shall be bound by the
provisions of this Section 2.

        2.2 The term "Senior Indebtedness" shall mean any and all indebtedness
and obligations of the Company including without limitation principal, premium,
if any, interest fees, costs and other expenses, under any documents or
instruments evidencing, creating, governing or securing any loan made by a
banking or financial institution to the Company and any secured loan and
indebtedness constituting deferrals, renewals, extensions and refundings of any
such



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indebtedness, unless the instrument for such loan provides that such
indebtedness is subordinated to, or on a parity with, this Note, or otherwise
not superior in right or payment to this Note.

        2.3 Upon the liquidation or reorganization of the Company (whether in
bankruptcy, insolvency, or receivership proceedings, or upon an assignment for
the benefit of creditors, or any other marshalling of the assets and liabilities
of the Company, or otherwise):

        (a) all Senior Indebtedness shall first be paid in full, or provision
     made for such payment in cash, before any payment is made on account of the
     principal or interest on the indebtedness evidenced by this Note; and

        (b) any distribution of assets of the Company, whether in cash, property
     or securities (other than securities of the Company or any other
     corporation provided for by the plan if reorganization or readjustment
     which does not alter or impair, within the meaning of 11 U.S.C. 1124, the
     rights of the holders of Senior Indebtedness, the payment of which the
     securities is subordinated, at least to the extent provided in this Section
     2 with respect to this Note, to the payment of all Senior Indebtedness
     which may be at the time outstanding), on account of the indebtedness
     evidenced by this Note to which the holders of this Note would be entitled
     except for the provisions of this Section 2, shall be paid or delivered by
     the trustee in bankruptcy, receiver, assignee for benefit of creditors, or
     other liquidating agent making such payment, or distribution, direct to the
     holders of Senior Indebtedness or their representatives, to the extent
     necessary to pay in full all Senior Indebtedness after giving effect to any
     other payment or distribution, or provision therefore in cash, to the
     holders of such Senior Indebtedness.

        2.4 Upon the maturity of any of the Senior Indebtedness by lapse of
time, acceleration or otherwise, all principal of and interest due thereon shall
first be paid in full, or such payment duly provided for in cash or in a manner
satisfactory to the holders of the Senior Indebtedness, before any payment is
made on account of the principal or interest on this Note.

        2.5 Upon the occurrence of an event of default with respect to any of
the Senior Indebtedness, which event would permit the holder of such Senior
Indebtedness to accelerate the maturity thereof (and in addition, if the default
is other than default in the payment of principal of, premium, if any, or
interest on the Senior Indebtedness, upon written notice of said default given
to the Company and to the holder of the Note by the holders of the Senior
Indebtedness) then, unless and until such event of default shall have been cured
or waived or shall have ceased to exist, no payment shall be made by the Company
with respect to the principal or interest on this Note.

        2.6 In the event that, contrary to the provisions of Section 2.3, 2.4 or
2.5 hereof, any payment or distribution of assets of the Company of any
character, whether in cash, securities or other property, is received by the
holder of this Note before the Senior Indebtedness is paid in full, such payment
or distribution shall be held by the holder of this Note in trust for



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the benefit of, and will be paid over or delivered to, the holders of the Senior
Indebtedness (or their representative or representatives) until the Senior
Indebtedness has been paid in full, after giving effect to the concurrent
payment or distribution (or provision therefore) to the holders of the Senior
Indebtedness.

        2.7 Upon the occurrence of any of the events described in Section 2.3,
2.4 or 2.5, and subject to the payment in full of all Senior Indebtedness, the
holder of this Note will not exercise any collection rights or any other rights
or remedies with respect to this Note, including, without limitation, any action
in any court of law to obtain a judgment on any indebtedness then outstanding on
this Note, without the prior written consent of the holders of the Senior
Indebtedness.

        2.8 Subject to the payment in full of all Senior Indebtedness, the
holder of this Note shall be subrogated (pro rata based on respective amounts
paid over for the benefit of the holders of Senior Indebtedness with the holders
of any other subordinated indebtedness of the Company that by its terms ranks
pari passu with this Note such subordinated indebtedness being hereinafter in
this Section 2.8 referred to as "pari passu indebtedness") to the rights of the
holders of Senior Indebtedness to receive payments or distributions of assets of
the Company made on Senior Indebtedness until the principal of and interest on
this Note shall be paid in full; and, for the purposes of such subrogation, no
payment distributions to the holders of Senior Indebtedness of any cash,
property or securities as a result of this subordination shall be deemed to be a
payment by the Company to or on account of Senior Indebtedness, it being
understood that the provisions of this Section 2 are solely for the purpose of
defining the relative rights of the holders of this Note and the holders of pari
passu indebtedness and the holders of Senior Indebtedness.

        2.9 No right of any present holder of the Senior Indebtedness to enforce
subordination as provided in this Section 2 will at any time in any way be
prejudiced or impaired by any act or failure to act, in good faith, by any such
holder, regardless of any knowledge thereof which any such holder may have or be
otherwise charged with.

        2.10 As long as none of the events described in Section 2.3, 2.4 and 2.5
have occurred, the holder of this Note shall be entitled to receive and retain
all regularly scheduled payments of principal and interest under this Note,
provided, however, that the holder of this Note shall not accept, nor shall the
Company make, any unauthorized prepayment on the Note, nor amend the payment
schedule under this Note, without the prior written consent of holder of the
Senior Indebtedness.

     3. EVENTS OF DEFAULT. This Note, together with accrued and unpaid interest
thereon, shall become and be due and payable upon demand made by the holder
hereof, without presentation, protest or further demand or notice of any kind
(all of which are expressly waived by the Company), if one or more of the
following events ("Events of Default") shall occur for any reason whatsoever
(and whether such occurrence shall be voluntary or involuntary or come about or
be affected by operation of law or pursuant to or in compliance with any
judgment, decree or order of any court or any order, rule or regulation of any
administrative or governmental body) and be continuing at the time of such
demand:



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        (a) default in the payment of principal or interest on the Note whether
     at maturity, by acceleration or otherwise, and continuance thereof for a
     period of 10 days following written notice to the Company specifying such
     default; or

        (b) the entry of a decree or order by a court having jurisdiction in the
     premises (i) for relief in respect of the Company in an involuntary case or
     proceeding under any federal or state bankruptcy, insolvency,
     reorganization or similar law or (ii) adjudging the Company a bankrupt or
     insolvent, or approving as properly filed a petition seeking
     reorganization, arrangement, adjustment or composition of or in respect of
     the Company under federal bankruptcy law or any other applicable federal or
     state law, or appointing a custodian, receiver, liquidator, assignee,
     trustee, sequestrator or other similar official of the Company or of any
     substantial part of its property, or ordering the winding up or liquidation
     of its affairs, and the continuance of any such decree or order unstayed
     and in effect for a period of 60 consecutive days; or

        (c) the institution by the Company of a voluntary case or proceeding
     under any federal or state bankruptcy, insolvency, reorganization or
     similar law or of any case or proceeding to be adjudicated a bankrupt or
     insolvent, or the consent by it to the entry of a decree or order for
     relief in respect to the entry of a decree or order for relief in respect
     of the Company, in an involuntary case or proceeding under any applicable
     federal or state bankruptcy, insolvency, reorganization or other similar
     law or to the institution of any bankruptcy or insolvency case or
     proceeding against it, or the filing by it of a petition or answer or
     consent seeking reorganization or relief under federal bankruptcy law or
     any other applicable federal or state law to the filing of such petition or
     to the appointment of or taking possession by a custodian, receiver,
     liquidator, assignee, trustee, sequestrator or similar official of the
     Company or of any substantial part of its property, or the making by it of
     an assignment for the benefit of creditors, or the admission by it in
     writing of its inability to pay its debts generally as they become due, or
     the taking of corporate action by the Company in furtherance of any such
     action; or

        (d) default In the payment of any amount due or performance of any
     obligation under any Senior Indebtedness, or under any other material
     indebtedness of the Company.

     4. REMEDIES. In case of one or more of the Events of Default specified in
Section 3 of this Note shall happen and be continuing, the holder of this Note
may, at its option, declare by notice to the Company, that this Note shall
thereupon be and become, forthwith due and payable, together with accrued
interest thereon, and may proceed to protect and enforce its rights by suit in
equity, action at law and/or by other appropriate proceeding, whether for the
specific



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performance (to the extent permitted by law) of any covenant or agreement
contained in this Note or in aid of the exercise of any power granted in this
Note, or may proceed to enforce the payment of this Note or to enforce any other
legal or equitable right or the holder of this Note. No remedy herein conferred
upon the holder is intended to be exclusive or any other remedy, shall be
cumulative and shall be in addition to every other remedy given hereunder or now
or otherwise. If any holder of this Note retains an attorney in connection with
any default or to collect, enforce or defend this Note in any lawsuit or in any
reorganization, bankruptcy or other proceeding, then the Company agrees to pay
to each such holder, in addition to principal and interest, all reasonable costs
and expenses incurred by such holder in trying to collect this Note or in such
suit or proceeding, including reasonable attorneys' fees.

     5. TRANSFER BY HOLDER. THIS NOTE HAS NOT BEEN REGISTERED WITH THE
SECURITIES AND EXCHANGE COMMISSION UNDER THE SECURITIES ACT OF 1933, AS AMENDED
(THE "ACT") OR UNDER THE SECURITIES LAWS OF ANY STATE. THIS NOTE MAY NOT BE
SOLD, TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED OF UNLESS REGISTERED UNDER THE
ACT AND UNDER APPLICABLE STATE SECURITIES LAWS, OR AN EXEMPTION FROM
REGISTRATION IS AVAILABLE AND A FAVORABLE OPINION OF COUNSEL FOR THE COMPANY TO
THAT EFFECT IS OBTAINED.

     6. APPLICABLE LAW. This Note shall be governed by, and construed in
accordance with the laws of the State of Ohio applicable to contracts made and
performed entirely within that state.

     7. SUCCESSORS. All the covenants, stipulations, promises and agreements in
this Note contained by or on behalf of the Company shall bind its successors and
assigns, whether so expressed or not.

     8. NO IMPLIED WAIVER. No course of dealing between the Company and the
holder hereof shall operate as a waiver of any right of any holder hereof and no
delay on the part of the holder hereof in exercising any right hereunder shall
so operate. This Note may be amended only by written instrument signed by the
party to be charged.

     9. HEADINGS. The headings of the Sections and subsections of this Note are
inserted for convenience only and do not constitute a part of this Note.

     10. TRANSFER OR EXCHANGE OF NOTES. The Company shall keep at its office a
register in which the Company shall provide for the registration of the Note and
for the registration of transfer and exchange of the Note. The holder of this
Note at its option may either in person or by duly authorized attorney-in-fact
surrender the game for registration of transfer or exchange at the office of the
Company and, without expense to such holder (other than transfer taxes, if any),
receive in exchange therefor a Note or Notes, each in the principal amount as
such holder may reasonably request, dated as of the date to which interest has
been paid on this Note, and payable to, and registered in the name or names of,
such person or persons as may be designated by such holder, for the same
aggregate principal amount as the then unpaid principal amount of this Note;
provided, no transfer or exchange will be permitted unless made in compliance
with the


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restrictions on transfer described in Section 5 above. Every Note presented or
surrendered for registration of transfer or exchange shall be duly endorsed, or
shall be accompanied by a written instrument of transfer duly executed, by the
holder of such Note so made and delivered in exchange for this Note shall in all
other respects be in the same form and have the same terms as this Note. No
transfer or exchange of any Note shall be valid unless made in the foregoing
manner at such office.

     IN WITNESS WHEREOF, Superconductive Components, Inc. has caused this Note
to be signed in its corporate name by its officer thereunto duly authorized, and
to be dated as of the day and year first above written.

                                           SUPERCONDUCTIVE COMPONENTS, INC.,
                                           an Ohio corporation


                                           By: /s/ Edward R. Funk
                                               --------------------------------


                                           Name: Edward R. Funk
                                                 ------------------------------


                                           Title: President
                                                  -----------------------------

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