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                                                                    EXHIBIT 10.2



Loan Number:          7996-314107-2000001

                                 REVOLVING NOTE
                                  (Prime\LIBOR)

Date:                          July 31, 1997
Principal Amount:              $20,000,000.00
Interest Rate:                 Variable Rate for LIBO Fixed Rate
Maturity Date:                 July 05, 2000
Borrower:                      SEAMED CORPORATION


        1.     PROMISE TO PAY. SEAMED CORPORATION ("Borrower") promises to pay
to KEYBANK NATIONAL ASSOCIATION, Seattle Metropolitan Commercial Banking Office,
700 Fifth Avenue, Seattle, WA 98111 ("Lender"), or order, in lawful money of the
United States of America, the principal amount set forth above or so much as may
be outstanding, together with interest on the unpaid outstanding principal
balance of each advance. Interest shall be calculated from the date of each
advance until repayment of each advance.

        2.     PAYMENT. Borrower will pay this loan on demand, or if no demand
is made, on the Maturity Date set forth above. In addition, Borrower will pay
regular quarterly payments of accrued unpaid interest, beginning August 05,
1997, and continuing on the same day of each quarter after that. Interest on
this Note is computed on a 365/360 simple interest basis; that is, by applying
the ratio of the annual interest rate over a year of 360 days, times the
outstanding principal balance, times the actual number of days the principal
balance is outstanding. Borrower will pay Lender at Lender's address shown above
or at such other place as Lender may designate in writing. Unless otherwise
agreed or required by applicable law, payments will be applied first to accrued
unpaid interest, then to principal, and any remaining amount to any unpaid
collection costs and late charges.

        3.     INTEREST RATE. This Note shall bear interest at the Variable
Rate, unless Borrower elects to have an Advance bear interest at a LIBO Fixed
Rate, as described below. Advances may bear interest at different rates.

               (a)    Variable Rate. Unless Borrower elects to have an advance
        bear interest at a Fixed Rate, amounts outstanding hereunder shall bear
        interest from the date of advance at a floating rate equal to the Prime
        Rate minus one quarter percent (0.250%) (the "Variable Rate"). "Prime
        Rate" means the floating commercial loan rate announced from time to
        time by Lender as its "prime rate", and is not necessarily the lowest
        rate offered by Lender. Changes in the Variable Rate will be effective
        on the date the Prime Rate changes.

               (b)    LIBO Fixed Rate. Borrower may elect to have one or more
        advances (each a "Fixed Rate Advance") bear interest for a term of 30,
        60, 90, 120, or 180 days


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        (the "Advance Period") at a fixed rate of interest equal to the
        then-current LIBO Quote for the requested Advance Period, plus one and
        20/100 percent (1.200%) (the "LIBO Fixed Rate"). "LIBO Quote" means a
        rate calculated by Lender acting in good faith, which Lender determines
        with reference to, but which may be different from, its LIBOR or
        Eurodollar based costs of funds, on the date of the advance request for
        the Advance Period selected by Borrower. The formula used by Lender in
        determining the LIBO Quote is within its absolute discretion and may be
        changed from time to time. Borrower may not select an Advance Period
        that extends beyond the Maturity Date of the Note. Upon expiration of
        the applicable Advance Period, Borrower may elect to roll the advance to
        a new LIBO Fixed Rate, to pay the advance off, or have the advance bear
        interest thereafter at the Variable Rate. If Borrower fails to elect any
        of these options, the advance will thereafter bear interest at the
        Variable Rate until Borrower selects a new LIBO Fixed Rate.

               (c)    Restrictions. Each Libor Rate Advance shall be in the
        minimum amount of Two Hundred Thousand Dollars ($200,000.00).

        4.     PREPAYMENT. Borrower agrees that all loan fees and other prepaid
finance charges are earned fully as of the date of the loan and will not be
subject to refund upon early payment (whether voluntary or as a result of
default), except as otherwise required by law. This Note evidences a revolving
line, which may be borrowed, repaid, and re-borrowed from time until maturity or
earlier termination. Principal payments shall first be applied to reduce
principal bearing interest at the Variable Rate, then to Fixed Rate Advances. If
Borrower prepays a Fixed Rate Advance prior to the last day of the applicable
Advance Period, Borrower shall also pay a Prepayment Premium, calculated as set
forth below. Lender will be entitled to receive the Prepayment Premium
regardless of whether prepayment is voluntary or involuntary, (including a
demand on the Note at a time when Borrower is in default hereunder) but not in
the event of a demand by Lender prior to the stated Termination Date in the
absence of default under this Note. Borrower acknowledges that Lender may or may
not, in any particular case, match-fund a Fixed Rate Advance and Borrower agrees
that Lender will be entitled to receive the Prepayment Premium irrespective of
match-funding. Early payments will not, unless agreed to by Lender in writing,
relieve Borrower of Borrower's obligation to continue to make payments of
accrued unpaid interest. Rather, they will reduce the principal balance due.

        5.     LATE CHARGE. If a payment is 10 days or more late, Borrower will
be charged 5.000% of the regularly scheduled payment or $10.00, whichever is
greater.

        6.     DEFAULT. Borrower will be in default if any of the following
happens: (a) Borrower fails to make any payment when due. (b) Borrower breaks
any promise Borrower has made to Lender, or Borrower fails to comply with or to
perform when due any other term, obligation, covenant, or condition contained in
this Note or any agreement related to this Note, or in any other agreement or
loan Borrower has with Lender. (c) Any representation or statement made or
furnished to Lender by Borrower or on Borrower's behalf is false or misleading
in any material respect, either now or at the time made or furnished. (d)
Borrower becomes insolvent, a receiver is appointed for any part of Borrower's
property, Borrower makes an assignment for the



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benefit of creditors, or any proceeding is commenced either by Borrower or
against Borrower under any bankruptcy or insolvency laws. (e) Any creditor tries
to take any of Borrower's property on or in which Lender has a lien or security
interest. This includes a garnishment of any of Borrower's accounts with Lender.
(f) Any of the events described in this default section occurs with respect to
any guarantor of this Note. (g) A material adverse change occurs in Borrower's
financial condition, or Lender believes the prospect of payment or performance
of the Indebtedness is impaired. If any default, other than a default in
payment, is curable and if Borrower has not been given a notice of a breach of
the same provision of this Note within the preceding twelve (12) months, it may
be cured (and no event of default will have occurred) if Borrower, afar
receiving written notice from Lender demanding cure of such default: (a) cures
the default within fifteen (15) days; or (b) if the cure requires more than
fifteen (15) days, immediately initiates steps which Lender deems in Lender's
sole discretion to be sufficient to cure the default and thereafter continues
and completes all reasonable and necessary steps sufficient to produce
compliance as soon as reasonably practical.

        7.     LENDER'S RIGHTS. Upon default, Lender may declare the entire
unpaid principal balance on this Note and all accrued unpaid interest
immediately due, without notice, and then Borrower must pay that amount. Upon
default, including failure to pay upon final maturity, Lender, at its option,
may also increase the interest rate on this Note to a floating rate equal to the
Prime Rate plus 5.00% per annum. Lender may hire or pay someone else to help
collect this Note if Borrower does not pay. Borrower also will pay Lender that
amount. This includes, subject to any limits under applicable law, court costs,
Lender's attorneys' fees and Lender's legal expenses whether or not there is a
lawsuit, including attorneys' fees and legal expenses for bankruptcy proceedings
(including efforts to modify or vacate any automatic stay or injunction),
appeals, and any anticipated post-judgment collection services. This Note has
been delivered to and accepted by Lender in the State of Washington. If there is
a lawsuit, Borrower agrees upon Lender's request to submit to the jurisdiction
of the courts of King or Pierce County, State of Washington. This Note shall be
governed by and construed in accordance with the laws of the State of
Washington.

        8.     DISHONORED ITEM FEE. Borrower will pay a fee to Lender of $10.00
if Borrower makes a payment on Borrower's loan and the check or preauthorized
charge with which Borrower pays is later dishonored.

        9.     LINE OF CREDIT. This Note evidences a revolving line of credit.
Advances under this Note may be requested orally by Borrower or as provided in
this paragraph. Lender may, but need not, require that all oral requests be
confirmed in writing. All communications, instructions, or directions by
telephone or otherwise to Lender are to be directed to Lender's office shown
above. The following party or parties are authorized as provided in this
paragraph to request advances under the line of credit until Lender receives
from Borrower at Lender's address shown above written notice of revocation of
their authority: Edgar Rampy and W. Robert Berg. Borrower agrees to be liable
for all sums either advanced in accordance with the instructions of an
authorized person or credited to any of Borrower's accounts with Lender. The
unpaid principal balance owing on this Note at any time may be evidenced by
endorsements on this Note or by Lender's internal record, including daily
computer print-outs. Lender will have no



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obligation to advance funds under this Note if: (a) Borrower or any guarantor is
in default under the terms of this Note or any agreement that Borrower or any
guarantor has with Lender, including any agreement made in connection with the
signing of this Note; (b) Borrower or any guarantor ceases doing business or is
insolvent; (c) any guarantor seeks, claims or otherwise attempts to limit,
modify or revoke such guarantor's guarantee of this Note or any other loan with
Lender; or (d) Borrower has applied funds provided pursuant to this Note for
purposes other than those authorized by Lender.

        10.    PREPAYMENT PREMIUM. If for any reason Borrower shall prepay all
or a portion of the principal amount of any Fixed Rate Advance prior to the
expiration of the applicable Advance Period, Borrower shall also pay Lender a
Prepayment Premium. The Prepayment Premium will be equal to the present value,
at the time of prepayment (the "Prepayment Date"), of the excess of (i) the
interest that would have been payable on the amount prepaid at the interest rate
applicable to the Advance(s) from the Prepayment Date to the expiration date of
the Advance Period applicable to such Advance, over (ii) the interest that would
be chargeable on a note equal to the amount prepaid at a New Rate. The "New
Rate" shall be equal to the United States Treasury Security yield on a security
with a current remaining term to maturity the same as the Advance at the
Prepayment Date, plus the comparable interest rate spread as the Advance had to
the United States Treasury Security yield with the same maturity. The present
value shall be computed using 1/12th of the New Rate as the monthly discount
rate. If there is no U.S. Treasury Security with a comparable maturity, Lender
will determine the appropriate yield by interpolating between maturities.

        11.    SWAP PROVISIONS. If Borrower and Lender are entering or
subsequently enter into an interest rate swap agreement related to this Note (a
"Swap"), then the following provisions shall apply: This Note shall be deemed to
be modified so that interest will accrue during the period of time the Swap is
in effect at a Fixed Rate equal to the rate designated in the Confirmation
issued by Lender applicable to such Swap, and calculated in accordance with the
procedures and quotation sources used in connection with the Swap. Upon a
termination of the Swap that does not constitute a default under this Note, the
interest and payment provisions under this Note shall, at Lender's sole and
exclusive option, revert to what they would have been absent the Swap. If this
Note is prepaid, then Lender shall have the right in its sole and absolute
discretion to terminate the Swap upon or at any time after such prepayment. In
addition to any premium that may be due under this Note upon prepayment,
Borrower will pay any amounts that may be due to Lender upon Early Termination
(as defined in the 1991 ISDA Definitions published by the International Swap
Dealers Association, Inc.) of the Swap.

        12.    ADDITIONAL PROVISIONS. Any advance that Lender in its sole
discretion may permit after the final payment date provided in this Note will be
due on demand and otherwise subject to the terms of this Note. If there is a
statutory change in state or federal law (including without limitation, a change
related to required reserves under applicable bank regulatory law or a change in
any provision of the Internal Revenue Code), or any regulation or interpretation
issued thereunder, that lowers Lender's effective yield on this Note, Lender
shall notify Borrower in writing of the change, and Borrower shall pay as
additional interest on this 


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Note, the amount necessary to compensate Lender for the amount by which
Lender's effective yield was reduced.

        13.    GENERAL PROVISIONS. Lender may delay or forgo enforcing any of
its rights and remedies under this Note without losing them. Borrower and any
other person who signs, guarantees or endorses this Note, to the extent allowed
by law, each waive presentment, demand for payment, protest and notice of
dishonor. Upon any change in the terms of this Note, and unless otherwise
expressly stated in writing, no party who signs this Note, whether as maker,
guarantor, accommodation maker or endorser, shall be released from liability.
All such parties agree that Lender may renew or extend (repeatedly and for any
length of time) this loan, or release any party or guarantor or collateral; or
impair, fail to realize upon or perfect Lender's security interest in the
collateral; and take any other action deemed necessary by Lender the consent of
or notice to anyone. All such parties also agree that Lender may modify this
loan without the consent of or notice to anyone other than the party with whom
the modification is made.

        14.    AFFIRMATIVE COVENANTS. The maximum amount of principal under this
note is limited to $10,000,000.00 for the first year of this loan. Provided
there have been no defaults on the loan during that period of time, the maximum
amount will increase to $20,000,000.00 during years two and three of the loan.

        ORAL AGREEMENTS OR ORAL COMMITMENTS TO LOAN MONEY, EXTEND CREDIT OR TO
        FORBEAR FROM ENFORCING REPAYMENT OF A DEBT ARE NOT ENFORCEABLE UNDER
        WASHINGTON LAW.


KEYBANK NATIONAL ASSOCIATION               BORROWER:
                                           SEAMED CORPORATION

 /s/ SARAH A. BULLOCK                       /s/ EDGAR F. RAMPY
-----------------------------------        ------------------------------------
SARAH BULLOCK, Authorized Officer          EDGAR F. RAMPY, Vice President







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