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                                                                   Exhibit 10.17

                             SECURED PROMISSORY NOTE

                                                        October 4, 2001
$275,000.00.00                                          Rocky Hill, Connecticut

     FOR VALUE RECEIVED, Walter W. Schroeder, III (the "Maker") promises to pay
to Proton Energy Systems, Inc., a Delaware corporation (the "Company"), or
order, at the offices of the Company or at such other place as the holder of
this Note may designate, the principal sum of TWO HUNDRED SEVENTY FIVE THOUSAND
DOLLARS ($275,000.00), together with interest on the unpaid principal balance of
this Note from time to time outstanding at the prime rate in effect from time to
time. The term "prime rate" at any time shall mean the rate of interest then
most recently announced by Chase Manhattan Bank as its prime rate. Principal and
accrued interest shall be due and payable as follows:

     (i)  on the last day of each calendar month during the term of this Note
          (beginning with October 31, 2001), until this Note is repaid in full,
          the Maker shall pay $10,000.00 to the Company; and

     (ii) the entire outstanding balance of principal and accrued but unpaid
          interest shall be paid in full on October 3, 2003.

     "Makers Affiliates" shall mean the Makers' spouse, any child or grandchild
of Maker or any trust, corporation or other entity organized for the benefit of
Maker or any of the foregoing relatives of Maker.

     Interest on this Note shall be computed on the basis of a year of 365 days
for the actual number of days elapsed. All payments made under this Note shall
be applied first to accrued but unpaid interest and then to reduce the principal
balance of this Note. All payments by the Maker under this Note shall be in
immediately available funds.

     Payment of this Note is secured by a security interest in certain property
of the Maker pursuant to a pledge agreement of even date herewith between the
Maker and the Company (the "Pledge Agreement").

     This Note shall become immediately due and payable without notice or demand
upon the occurrence at any time of any of the following events of default
(individually, "an Event of Default" and collectively, "Events of Default"):

     (i)  the final date of the Maker's employment with the Company;

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     (ii)  the institution against the Maker or any indorser or guarantor of
           this Note of any proceedings under the United States Bankruptcy Code
           or any other federal or state bankruptcy, reorganization,
           receivership, insolvency or other similar law affecting the rights of
           creditors generally, which proceeding is not dismissed within thirty
           (30) days of filing;

     (iii) the institution by the Maker or any indorser or guarantor of this
           Note of any proceedings under the United States Bankruptcy Code or
           any other federal or state bankruptcy, reorganization, receivership,
           insolvency or other similar law affecting the rights of creditors
           generally or the making by the Maker or any indorser or guarantor of
           this Note of a composition or an assignment or trust mortgage for the
           benefit of creditors;

     (iv)  the occurrence of any event of default under the Pledge Agreement; or

     (v)   the Maker dies or becomes incapacitated, or a conservator or guardian
           of the Maker is appointed, or the Maker suffers any other legal
           disability.

     Upon the occurrence of an Event of Default, the holder shall have then, or
at any time thereafter, all of the rights and remedies afforded by the Uniform
Commercial Code as from time to time in effect in the State of Connecticut or
afforded by other applicable law.

     Every amount overdue under this Note shall bear interest from and after the
date on which such amount first became overdue at an annual rate which is two
(2) percentage points above the rate per year specified in the first paragraph
of this Note. Such interest on overdue amounts under this Note shall be payable
on demand and shall accrue and be compounded monthly until the obligation of the
Maker with respect to the payment of such interest has been discharged (whether
before or after judgment).

     In no event shall any interest charged, collected or reserved under this
Note exceed the maximum rate then permitted by applicable law and if any such
payment is paid by the Maker, then such excess sum shall be credited by the
holder as a payment of principal.

     All payments by the Maker under this Note shall be made without set-off or
counterclaim and be free and clear and without any deduction or withholding for
any taxes or fees of any nature whatever, unless the obligation to make such
deduction or withholding is imposed by law. The Maker shall pay and save the
holder harmless from all liabilities with respect to or resulting from any delay
or omission to make any such deduction or withholding required by law.

     No reference in this Note to the Pledge Agreement or any guaranty or other
document shall impair the obligation of the Maker to pay all amounts under this
Note strictly in accordance with the terms of this Note.

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     The Maker agrees to pay on demand all costs of collection, including
reasonable attorneys' fees, incurred by the holder in enforcing the obligations
of the Maker under this Note.

     No delay or omission on the part of the holder in exercising any right
under this Note or the Pledge Agreement shall operate as a waiver of such right
or of any other right of such holder, nor shall any delay, omission or waiver on
any one occasion be deemed a bar to or waiver of the same or any other right on
any future occasion. The Maker and every indorser or guarantor of this Note
regardless of the time, order or place of signing waives presentment, demand,
protest and notices of every kind and assents to any extension or postponement
of the time of payment or any other indulgence, to any substitution, exchange or
release of collateral, and to the addition or release of any other party or
person primarily or secondarily liable.

     This Note may be prepaid in whole or in part at any time or from time to
time by the Maker. Any such prepayment shall be without premium or penalty.

     None of the terms or provisions of this Note may be excluded, modified or
amended except by a written instrument duly executed on behalf of the holder
expressly referring to this Note and setting forth the provision so excluded,
modified or amended.

     All rights and obligations hereunder shall be governed by the laws of the
State of Connecticut and this Note is executed as an instrument under seal.

     IN WITNESS WHEREOF, this Note has been executed as of the date first
written above.

                                                 ______________________________
                                                 Walter W. Schroeder, III

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