EXHIBIT 10.26
 
                            REVOLVING REDUCING NOTE


$30,000,000.00                                             Palo Alto, California
                                                                January 27, 1999

     FOR VALUE RECEIVED, the undersigned EXPONENT FAILURE ANALYSIS ASSOCIATES,
INC. ("Borrower") promises to pay to the order of WELLS FARGO BANK, NATIONAL
ASSOCIATION ("Bank") at its office at Peninsula RCBO, 400 Hamilton Avenue, Palo
Alto, CA 94301, or at such other place as the holder hereof may designate, in
lawful money of the United States of America and in immediately available funds,
the principal sum of Thirty Million Dollars ($30,000,000.00), or so much thereof
as may be advanced and be outstanding, with interest thereon, to be computed on
each advance from the date of its disbursement as set forth herein.

DEFINITIONS:

     As used herein, the following terms shall have the meanings set forth after
each, and any other term defined in this Note shall have the meaning set forth
at the place defined:

     (a) "Business Day" means any day except a Saturday, Sunday or any other day
on which commercial banks in California are authorized or required by law to
close.

     (b) "Fixed Rate Term" means a period commencing on a Business Day and
continuing for one (1), two (2), three (3), six (6), or nine (9), or twelve (12)
months, as designated by Borrower, during which all or a portion of the
outstanding principal balance of this Note bears interest determined in relation
to LIBOR; provided however, that no Fixed Rate Term may be selected for a
principal amount less than Five Hundred Thousand Dollars ($500,000.00); and
provided further, that no Fixed Rate Term shall extend beyond the scheduled
maturity date hereof. If any Fixed Rate Term would end on a day which is not a
Business Day, then such Fixed Rate Term shall be extended to the next succeeding
Business Day.

     (c) "LIBOR" means the rate per annum (rounded upward, if necessary, to the
nearest whole 1/8 of 1%) and determined pursuant to the following formula:

     LIBOR =             Base LIBOR              
               -------------------------------                                  
               100% - LIBOR Reserve Percentage

     (i) "Base LIBOR" means the rate per annum for United States dollar deposits
quoted by Bank as the Inter-Bank Market Offered Rate, with the understanding
that such rate is quoted by Bank for the purpose of calculating effective rates
of interest for loans making reference thereto, on the first day of a Fixed Rate
Term

 
for delivery of funds on said date for a period of time approximately equal to
the number of days in such Fixed Rate Term and in an amount approximately equal
to the principal amount to which such Fixed Rate Term applies. Borrower
understands and agrees that Bank may base its quotation of the Inter-Bank Market
Offered Rate upon such offers or other market indicators of the Inter-Bank
Market as Bank in its discretion deems appropriate including, but not limited
to, the rate offered for U.S. dollar deposits on the London Inter-Bank Market.

     (ii) "LIBOR Reserve Percentage" means the reserve percentage prescribed by
the Board of Governors of the Federal Reserve System (or any successor) for
"Eurocurrency Liabilities" (as defined in Regulation D of the Federal Reserve
Board, as amended), adjusted by Bank for expected changes in such reserve
percentage during the applicable Fixed Rate Term.

     (d)  "Prime Rate" means at any time the rate of interest most recently
announced within Bank at its principal office as its Prime Rate, with the
understanding that the Prime Rate is one of Bank's base rates and serves as the
basis upon which effective rates of interest are calculated for those loans
making reference thereto, and is evidenced by the recording thereof after its
announcement in such internal publication or publications as Bank may designate.

INTEREST:

     (a)  Interest. The outstanding principal balance of this Note shall bear
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interest (computed on the basis of a 360-day year, actual days elapsed) either
(i) at a fluctuating rate per annum one and one-half percent (1.5%) below the
Prime Rate in effect from time to time, or (ii) at a fixed rate per annum
determined by Bank to be one and one-quarter percent (1.25%) above LIBOR in
effect on the first day of the applicable Fixed Rate Term. When interest is
determined in relation to the Prime Rate, each change in the rate of interest
hereunder shall become effective on the date each Prime Rate change is announced
within Bank. With respect to each LIBOR selection hereunder, Bank is hereby
authorized to note the date, principal amount, interest rate and Fixed Rate Term
applicable thereto and any payments made thereon on Bank's books and records
(either manually or by electronic entry) and/or on any schedule attached to this
Note, which notations shall be prima facie evidence of the accuracy of the
information noted.

     (b)  Selection of Interest Rate Options. At any time any portion of this
          ----------------------------------                                 
Note bears interest determined in relation to LIBOR, it may be continued by
Borrower at the end of the Fixed Rate Term applicable thereto so that all or a
portion thereof bears interest determined in relation to the Prime Rate or to
LIBOR for a new Fixed Rate Term designated by Borrower. At any

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time any portion of this Note bears interest determined in relation to the Prime
Rate, Borrower may convert all or a portion thereof so that it bears interest
determined in relation to LIBOR for a Fixed Rate Term designated by Borrower. At
such time as Borrower requests an advance hereunder or wishes to select a LIBOR
option for all or a portion of the outstanding principal balance hereof, and at
the end of each Fixed Rate Term, Borrower shall give Bank notice specifying' (i)
the interest rate option selected by Borrower; (ii) the principal amount subject
thereto; and (iii) for each LIBOR selection, the length of the applicable Fixed
Rate Term. Any such notice may be given by telephone so long as, with respect to
each LIBOR selection, (A) Bank receives written confirmation from Borrower not
later than three (3) Business Days after such telephone notice is given, and (B)
such notice is given to Bank prior to 10:00 a.m., California time, on the first
day of the Fixed Rate Term. For each LIBOR option requested hereunder, Bank will
quote the applicable fixed rate to Borrower at approximately 10:00 a.m.,
California time, on the first day of the Fixed Rate Term. If Borrower does not
immediately accept the rate quoted by Bank, any subsequent acceptance by
Borrower shall be subject to a redetermination by Bank of the applicable fixed
rate; provided however, that if Borrower fails to accept any such rate by 11:00
a.m., California time, on the Business Day such quotation is given, then the
quoted rate shall expire and Bank shall have no obligation to permit a LIBOR
option to be selected on such day. If no specific designation of interest is
made at the time any advance is requested hereunder or at the end of any Fixed
Rate Term, Borrower shall be deemed to have made a Prime Rate interest selection
for such advance or the principal amount to which such Fixed Rate Term applied.

     (c)  Additional LIBOR Provisions.
          ---------------------------

     (i)  If Bank at any time shall determine that for any reason adequate and
reasonable means do not exist for ascertaining LIBOR, then Bank shall promptly
give notice thereof to Borrower.

     If such notice is given and until such notice has been withdrawn by Bank,
then (A) no new LIBOR option may be selected by Borrower, and (B) any portion of
the outstanding principal balance hereof which bears interest determined in
relation to LIBOR, subsequent to the end of the Fixed Rate Term applicable
thereto, shall bear interest determined in relation to the Prime Rate.

     (ii) If any law, treaty, rule, regulation or determination of a court or
governmental authority or any change therein or in the interpretation or
application thereof (each, a "Change in Law") shall make it unlawful for Bank
(A) to make LIBOR options available hereunder, or (B) to maintain interest rates
based on LIBOR, then in the former event, any obligation of Bank to make
available such unlawful LIBOR options shall immediately be

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cancelled, and in the latter event, any such unlawful LIBOR-based interest rates
then outstanding shall be converted, at Bank's option, so that interest on the
portion of the outstanding principal balance subject thereto is determined in
relation to the Prime Rate; provided however, that if any such Change in Law
shall permit any LIBOR-based interest rates to remain in effect until the
expiration of the Fixed Rate Term applicable thereto, then such permitted LIBOR-
based interest rates shall continue in effect until the expiration of such Fixed
Rate Term. Upon the occurrence of any of the foregoing events, Borrower shall
pay to Bank immediately upon demand such amounts as may be necessary to
compensate Bank for any fines, fees, charges, penalties or other costs incurred
or payable by Bank as a result thereof and which are attributable to any LIBOR
options made available to Borrower hereunder, and any reasonable allocation made
by Bank among its operations shall be conclusive and binding upon Borrower.

     (iii) If any Change in Law or compliance by Bank with any request or
directive (whether or not having the force of law) from any central bank or
other governmental authority shall.

      (A)  subject Bank to any tax, duty or other charge with respect to any
           LIBOR options, or change the basis of taxation of payments to Bank of
           principal, interest, fees or any other amount payable hereunder
           (except for changes in the rate of tax on the overall net income of
           Bank); or

      (B)  impose, modify or hold applicable any reserve, special deposit,
           compulsory loan or similar requirement against assets held by,
           deposits or other liabilities in or for the account of, advances or
           loans by, or any other acquisition of funds by any office of Bank; or

      (C)  impose on Bank any other condition;

and the result of any of the foregoing is to increase the cost to Bank of
making, renewing or maintaining any LIBOR options hereunder and/or to reduce any
amount receivable by Bank in connection therewith, then in any such case,
Borrower shall pay to Bank immediately upon demand such amounts as may be
necessary to compensate Bank for any additional costs incurred by Bank and/or
reductions in amounts received by Bank which are attributable to such LIBOR
options. In determining which costs incurred by Bank and/or reductions in
amounts received by Bank are attributable to any LIBOR options made available to
Borrower hereunder, any reasonable allocation made by Bank among its operations
shall be conclusive and binding upon Borrower.

      (d)  Payment of Interest. Interest accrued on this Note shall be payable
           -------------------  
on the last day of each month, commencing February 28, 1999.

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     (e)  Default Interest. From and after the maturity date of this Note, or
          ----------------                                                 
such earlier date as all principal owing hereunder becomes due and payable by
acceleration or otherwise, the outstanding principal balance of this Note shall
bear interest until paid in full at an increased rate per annum (computed on the
basis of a 360-day year, actual days elapsed) equal to four percent (4%) above
the rate of interest from time to time applicable to this Note.

BORROWING AND REPAYMENT:

     (a)  Borrowing and Repayment. Borrower may from time to time during the
          -----------------------  
term of this Note borrow, partially or wholly repay its outstanding borrowings,
and reborrow, subject to all of the limitations, terms and conditions of this
Note and of any document executed in connection with or governing this Note;
provided however, that the total outstanding borrowings under this Note shall
not at any time exceed the principal amount set forth above or such lesser
amount as shall at any time be available hereunder. The unpaid principal balance
of this obligation at any time shall be the total amounts advanced hereunder by
the holder hereof less the amount of principal payments made hereon by or for
any Borrower, which balance may be endorsed hereon from time to time by the
holder. The outstanding principal balance of this Note shall be due and payable
in full on January 31, 2009.

     (b)  Reductions in Availability. Notwithstanding the principal amount set
          --------------------------                                          
forth above, the maximum principal amount available under this Note shall be
reduced automatically and without further notice on each January 31, commencing
January 31, 2000, in accordance with the following schedule:



       Date                          Amount of Reduction
       ----                          -------------------
                                  
January 31, 2000                       $1,250,077.66
January 31, 2001                       $1,330,087.90
January 31, 2002                       $1,415,219.13
January 31, 2003                       $1,505,799.13
January 31, 2004                       $1,602,176.61
January 31, 2005                       $1,704,722.68
January 31, 2006                       $1,813,832.11
January 31, 2007                       $1,929,925.02
January 31, 2008                       $2,053,448.35


If the outstanding principal balance of this Note on any such date is greater
than the new maximum principal amount then available hereunder, Borrower shall
make a principal reduction on this Note on such date in an amount sufficient to
reduce the then outstanding principal balance hereof to an amount not greater
than said new maximum principal amount.

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     (c)  Advances. Advances hereunder, to the total amount of the principal sum
          --------                                                              
stated above, may be made by the holder at the oral or written request of (i)
Michael R. Gaulke, Terrence G. Boyle, Richard L. Schlenker or Jeanne L. Marzano,
any one acting alone, who are authorized to request advances and direct the
disposition of any advances until written notice of the revocation of such
authority is received by the holder at the office designated above, or (ii) any
person, with respect to advances deposited to the credit of any account of any
Borrower with the holder, which advances, when so deposited, shall be
conclusively presumed to have been made to or for the benefit of each Borrower
regardless of the fact that persons other than those authorized to request
advances may have authority to draw against such account. The holder shall have
no obligation to determine whether any person requesting an advance is or has
been authorized by any Borrower.

     (d)  Application of Payments. Each payment made on this Note shall be
          -----------------------                                         
credited first, to any interest then due and second, to the outstanding
principal balance hereof. All payments credited to principal shall be applied
first, to the outstanding principal balance of this Note which bears interest
determined in relation to the Prime Rate, if any, and second, to the outstanding
principal balance of this Note which bears interest determined in relation to
LIBOR, with such payments applied to the oldest Fixed Rate Term first.

PREPAYMENT:

     (a)  Prime Rate. Borrower may prepay principal on any portion of this Note
          ----------                                                           
which bears interest determined in relation to the Prime Rate at any time, in
any amount and without penalty.

     (b)  LIBOR. Borrower may prepay principal on any portion of this Note which
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bears interest determined in relation to LIBOR at any time and in the minimum
amount of Five Hundred Thousand Dollars ($500,000.00); provided however, that if
the outstanding principal balance of such portion of this Note is less than said
amount, the minimum prepayment amount shall be the entire outstanding principal
balance thereof. In consideration of Bank providing this prepayment option to
Borrower, or if any such portion of this Note shall become due and payable at
any time prior to the last day of the Fixed Rate Term applicable thereto by
acceleration or otherwise, Borrower shall pay to Bank immediately upon demand a
fee which is the sum of the discounted monthly differences for each month from
the month of prepayment through the month in which such Fixed Rate Term matures,
calculated as follows for each such month:

     (i)   Determine the amount of interest which would have accrued each month
           ---------                                                           
           on the amount prepaid at the interest rate applicable to such amount
           had it remained

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           outstanding until the last day of the Fixed Rate Term applicable
           thereto.

     (ii)  Subtract from the amount determined in (i) above the amount of
           --------
           interest which would have accrued for the same month on the amount
           prepaid for the remaining term of such Fixed Rate Term at LIBOR in
           effect on the date of prepayment for new loans made for such term and
           in a principal amount equal to the amount prepaid.

     (iii) If the result obtained in (ii) for any month is greater than zero,
           discount that difference by LIBOR used in (ii) above.

Each Borrower acknowledges that prepayment of such amount may result in Bank
incurring additional costs, expenses and/or liabilities, and that it is
difficult to ascertain the full extent of such costs, expenses and/or
liabilities. Each Borrower, therefore, agrees to pay the above-described
prepayment fee and agrees that said amount represents a reasonable estimate of
the prepayment costs, expenses and/or liabilities of Bank. If Borrower fails to
pay any prepayment fee when due, the amount of such prepayment fee shall
thereafter bear interest until paid at a rate per annum two percent (2%) above
the Prime Rate in effect from time to time (computed on the basis of a 360-day
year, actual days elapsed). Each change in the rate of interest on any such past
due prepayment fee shall become effective on the date each Prime Rate change is
announced within Bank.

EVENTS OF DEFAULT:

     The occurrence of any of the following shall constitute an "Event of
Default" under this Note:

     (a)   The failure to pay any principal, interest, fees or other charges
when due hereunder or under any contract, instrument or document executed in
connection with this Note.

     (b)   The filing of a petition by or against any Borrower, any guarantor of
this Note or any general partner or joint venturer in any Borrower which is a
partnership or a joint venture (with each such guarantor, general partner and/or
joint venturer referred to herein as a "Third Party Obligor") under any
provisions of the Bankruptcy Reform Act, Title 11 of the United States Code, as
amended or recodified from time to time, or under any similar or other law
relating to bankruptcy, insolvency, reorganization or other relief for debtors;
the appointment of a receiver, trustee, custodian or liquidator of or for any
part of the assets or property of any Borrower or Third Party Obligor; any
Borrower or Third Party Obligor becomes insolvent, makes a general assignment
for the benefit of creditors or is generally

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not paying its debts as they become due; or any attachment or like levy on any
property of any Borrower or Third Party Obligor.

     (c) The death or incapacity of any individual Borrower or Third Party
Obligor, or the dissolution or liquidation of any Borrower or Third Party
Obligor which is a corporation, partnership, joint venture or other type of
entity.

     (d) Any default in the payment or performance of any obligation, or any
defined event of default, under any provisions of any contract, instrument or
document pursuant to which any Borrower or Third Party Obligor has incurred any
obligation for borrowed money, any purchase obligation, or any other liability
of any kind to any person or entity, including the holder.

     (e) Any financial statement provided by any Borrower or Third Party Obligor
to Bank proves to be incorrect, false or misleading in any material respect.

     (f) Any sale or transfer of all or a substantial or material part of the
assets of any Borrower or Third Party Obligor other than in the ordinary course
of its business.

     (g) Any violation or breach of any provision of, or any defined event of
default under, any addendum to this Note or any loan agreement, guaranty,
security agreement, deed of trust, mortgage or other document executed in
connection with or securing this Note.

MISCELLANEOUS:

     (a) Remedies. Upon the sale, transfer, hypothecation, assignment or other
         --------  
encumbrance, whether voluntary, involuntary or by operation of law, of all or
any interest in any real property securing this Note, or upon the occurrence of
any Event of Default, the holder of this Note, at the holder's option, may
declare all sums of principal and interest outstanding hereunder to be
immediately due and payable without presentment, demand, notice of
nonperformance, notice of protest, protest or notice of dishonor, all of which
are expressly waived by each Borrower, and the obligation, if any, of the holder
to extend any further credit hereunder shall immediately cease and terminate.
Each Borrower shall pay to the holder immediately upon demand the full amount of
all payments, advances, charges, costs and expenses, including reasonable
attorneys' fees (to include outside counsel fees and all allocated costs of the
holder's in-house counsel), expended or incurred by the holder in connection
with the enforcement of the holder's rights and/or the collection of any amounts
which become due to the holder under this Note, and the prosecution or defense
of any action in any way related to this Note, including without limitation, any
action for declaratory relief, whether incurred at the trial or appellate level,
in an

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arbitration proceeding or otherwise, and including any of the foregoing incurred
in connection with any bankruptcy proceeding (including without limitation, any
adversary proceeding, contested matter or motion brought by Bank or any other
person) relating to any Borrower or any other person or entity.

     (b) Obligations Joint and Several. Should more than one person or entity
         -----------------------------                                       
sign this Note as a Borrower, the obligations of each such Borrower shall be
joint and several.

     (c) Governing Law. This Note shall be governed by and construed in
         -------------                                                 
accordance with the laws of the State of California.

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

EXPONENT FAILURE ANALYSIS ASSOCIATES, INC.


By:  /s/ Michael R. Gaulke
     ------------------------------------------
     Michael R. Gaulke
     President & Chief Executive Officer

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