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                                                                     EXHIBIT 4.2


THIS NOTE HAS NOT BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR
THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN
AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE
SECURITIES LAWS.

THIS NOTE IS SUBJECT TO THE TERMS OF A SUBORDINATION AGREEMENT BY MORGENTHALER
VENTURE PARTNERS V, L.P., AMPERSAND IV LIMITED PARTNERSHIP AND MOLEX
INCORPORATED IN FAVOR OF WELLS FARGO BANK MINNESOTA, NATIONAL ASSOCIATION DATED
AS OF MAY ___, 2001.


                                 SHELDAHL, INC.

                                      NOTE

$_________                                                         May __ , 2001


        FOR VALUE RECEIVED, Sheldahl, Inc., a Minnesota corporation (the
"Company"), hereby promises to pay to the order of _______________________ (the
"Holder"), the principal sum of _____________ ($________), on the Maturity Date
(as defined in the Purchase Agreement referred to below) together with interest
(computed on the basis of a 360 day year, so that 1/360th of the annualized
interest will accrue for each day that principal is outstanding) from the date
hereof until the date the unpaid balance of this Note and all amounts payable in
connection herewith have been paid to the Holder in full at the rate of interest
set forth in the Purchase Agreement. Interest may be paid quarterly on each of
March 31, June 30, September 30 and December 31 of each year, but, to the extent
not otherwise paid, interest shall be added to the principal quarterly on March
31, June 30, September 30 and December 31 of each year. All accrued interest
shall be payable in full on the date that this note is repaid in full.

        This Note is delivered as an instrument under seal.

        Payments of principal of, interest on and fees in connection with this
Note are to be made in lawful money of the United States of America as provided
in the Purchase Agreement. All amounts payable in connection herewith shall be
paid in cash on the date that this Note and all amounts payable in connection





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herewith are paid to the Holder. Payments shall be made to the Holder at such
place and by such means as provided in the Purchase Agreement.

        This Note is one of a series of notes issued pursuant to a Subordinated
Secured Notes Purchase Agreement, dated as of May ___, 2001 (as from time to
time amended, the "Purchase Agreement"), among the Company, as issuer, and the
Purchasers signatory thereto.

        This Note is entitled to the benefits of, and evidences obligations
incurred under, the Purchase Agreement, to which reference is made for a
description of the security for this Note and for a statement of the terms and
conditions relating to prepayment and repayment of the obligations evidenced
hereby. This Note may be subject to redemption prior to Maturity Date, as
provided in the Purchase Agreement.

        In case an Event of Default (as defined in the Purchase Agreement) shall
occur and be continuing, the principal of and accrued interest on this Note may
be declared to be due and payable in the manner and with the effect provided in
the Purchase Agreement.

        The Company hereby waives presentment, demand, protest or notice of any
kind in connection with this Note.

        THIS NOTE SHALL BE GOVERNED AND CONSTRUED UNDER THE LAWS OF THE
COMMONWEALTH OF MASSACHUSETTS.


                                       SHELDAHL, INC.


                                       By:
                                          --------------------------------------
                                          Name:
                                          Title: