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                            REVOLVING CREDIT NOTE
                               (this  "NOTE")

FOR VALUE RECEIVED, ON OR BEFORE the Termination Date (as defined in the Credit
Agreement), 1ST TECH CORPORATION, DARKHORSE SYSTEMS, INCORPORATED, and TANISYS
TECHNOLOGY, INC. (jointly and severally, "BORROWERS") promise to pay to the
order of THE CHASE MANHATTAN BANK ("Bank") at its office at 633 Third Avenue,
New York NY 10017 or such other location as Bank may designate, in immediately
available funds and lawful money of the United States of America, the sum of SIX
MILLION AND NO/100THS UNITED STATES DOLLARS (U.S. $6,000,000.00) or the
aggregate unpaid amount of all advances hereunder, whichever is lesser, plus
interest on the unpaid principal balance outstanding from time to time at a rate
per annum equal to the lesser of (i) the Stated Rate (as hereinafter defined)
from time to time in effect or (ii) the Highest Lawful Rate. If the Stated Rate
at any time exceeds the Highest Lawful Rate, the actual rate of interest to
accrue on the unpaid principal amount of this Note will be limited to the
Highest Lawful Rate, but any subsequent reductions in the Stated Rate due to
reductions in the Prime Rate will not reduce the interest rate payable upon the
unpaid principal amount of this Note below the Highest Lawful Rate until the
total amount of interest accrued on this Note equals the amount of interest
which would have accrued if the Stated Rate had at all times been in effect.
    The "STATED RATE" at any time shall be the rate indicated by the following
chart:

    DETERMINING RATIO        STATED RATE
    ------------------       ----------------
    Over 3.0X                Prime Rate +3.0%
    l.5X to 3.0X             Prime Rate +2.0%
    1.0X top 1.4X            Prime Rate +1.5%
    Less than I.0X           Prime Rate +1.0%

    The "DETERMINING RATIO" on any date shall be the ratio (determined for all
Borrowers combined, as of the end of the most recently ended calendar month) of
(i) Indebtedness to (ii) Annualized EBDITA (Adjusted). Annualized EBDITA
(Adjusted) shall mean (a) for the first 11 months after May 20, 1996, Borrowers'
average combined monthly EBDITA (Adjusted) (as correctly reported in Borrowers'
Compliance Certificates in the form of Exhibit C of the Credit Agreement) for
all months reported to the date the ratio is determined, times twelve; and (b)
thereafter, the sum of Borrowers' combined monthly EBDITA (Adjusted) (as
correctly reported) for the 12 months preceding the date the ratio is
determined.
    "PRIME RATE" means that rate as determined from time to time by Bank as
being its prime rate in effect at its principal office in New York City. Without
notice to Borrowers or any other Person, the Prime Rate shall change
automatically from time to time as and in the amount by which said prime rate
shall fluctuate with each such change to be effective as of the date of each
change in such prime rate. THE PRIME RATE IS A REFERENCE RATE AND DOES NOT
NECESSARILY REPRESENT THE LOWEST OR BEST RATE. BANK MAY MAKE LOANS AT RATES OF
INTEREST AT, ABOVE OR BELOW THE PRIME RATE.
    This Note is the Revolving Credit Note described in Section I .1.A of the
Credit Agreement (Borrowing Base) between Borrowers and Bank dated as of
February 21, 1997 (as amended, restated and supplemented from time to time, the
"Credit Agreement" or "Agreement") and sometimes referred to therein as the
Note.  Capitalized terms used in this Note have the meanings used in the
Agreement.
    Accrued and unpaid interest shall be due and payable monthly, beginning on
March 31, 1997, and continuing on the last day of each month thereafter and at
Termination Date when all unpaid principal and accrued and unpaid interest shall
be finally due and payable. Borrowers must make the payments required by
Sections 1.3, 1.4 and 1.5 of the Agreement.
    Interest shall be computed on the basis of the actual number of days
elapsed and a year comprised of 360 days, unless such calculation would result
in a usurious interest rate, in which case interest will be calculated on the
basis of a 365 or 366 day year, as applicable.
    All past-due principal and, as permitted by applicable law, interest on
this Note, shall, at Bank's option, bear interest at the Highest Lawful Rate, or
if applicable law shall not provide for a maximum nonusurious rate of interest,
at a rate per annum equal to eighteen percent (18%).
    The unpaid principal balance of this Note at any time shall be the total
amounts advanced by Bank, less the amount of all payments of principal.  Absent
manifest error, the records of Bank shall be conclusive as to amounts owed.
Subject to the terms and conditions of the Agreement, Borrowers may use all or
any part of the credit provided for herein at any time before the Termination
Date.
    Time is of the essence. Borrowers may at any time pay the full amount or
any part of this Note without the payment of any premium or fee. At Bank's sole
option, all payments may be applied to accrued interest, to principal, or to
both.
    If any Event of Default occurs, then Bank may exercise any and all rights
and remedies under the Loan Documents, at law, in equity or otherwise.
    Each and all Obligors severally waive notice, demand, presentment for
payment, notice of nonpayment, notice of intent to accelerate, notice of
acceleration, protest, notice of protest, and the filing of suit and diligence
in collecting this Note and all other demands and notices, and consent and agree
that their liabilities and obligations shall not be released or discharged by
any or all of the following, whether with or without notice to them or any of
them, and whether before or after the stated maturity hereof: (i) extensions of
the time of payment; (ii) renewals; ~ iii) acceptances of partial payments; (iv)
releases or substitutions of any collateral or any Obligor; and (v) failure, if
any, to perfect or maintain perfection of any security interest in any
collateral.  Each Obligor agrees that acceptance of any partial payment shall
not constitute a waiver.
    Bank and any subsequent owner or holder hereof reserves the right, in its
sole discretion, without notice to Borrowers, to sell participations or assign
its interest or both, in all or any part of this Note. For purposes of this
Note, any assignee or subsequent holder of this Note will be considered the
"Bank," and each successor to each Borrower will be considered a "Borrower."

IN WITNESS WHEREOF, Borrowers have executed this Note effective as of the
Effective Date.

BORROWER:  1ST TECH CORPORATION

By:  /s/ MARK C. HOLLIDAY                   
   -----------------------------------------
Typed Name:   Mark C. Holliday
Title:        President and CEO

BORROWER:  DARKHORSE SYSTEMS, INCORPORATED

By:  /s/ MARK C. HOLLIDAY                   
   -----------------------------------------
Typed Name:   Mark C. Holliday
Title:        President and CEO

BORROWER:  TANISYS TECHNOLOGY, INC.

By:  /s/ MARK C. HOLLIDAY                   
   -----------------------------------------
Typed Name:   Mark C. Holliday
Title:        President and CEO

BANK:    THE CHASE MANHATTAN BANK

By:  /s/ GEORGE LOUIS MCKINLEY              
   -----------------------------------------
Typed Name:   George Louis McKinley
Title:        Vice President