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                                                                    Exhibit 4.1b

                                  CURRENT NOTE



$3,000,000.00                                              May  14, 1998



              On January 31, 1999, for value received, HEI, Inc. (the
"Borrower") promises to pay to the order of Norwest Bank Minnesota, National
Association (the "Bank") at its office in Wayzata, Minnesota or at any other
place designated at any time by the holder hereof, in lawful money of the United
States of America, the principal sum of Three Million and no/100 Dollars
($3,000,000.00), or so much thereof as is disbursed and remains outstanding
thereunder on the due date hereof, as shown by the Bank's liability record,
together with interest (calculated on the basis of actual days elapsed in a 360
day year) on the unpaid balance hereof from the date hereof until this Note is
fully paid, at one of the following rates:

                (a)      Base Rate Option: A variable rate of interest equal to
                         the Base Rate in effect from time to time. The interest
                         rate under this option shall change as and when the
                         Base Rate changes.

                (b)      LIBOR Rate Option: The "LIBOR Rate" plus two percent
                         (2.0%). The "LIBOR Rate" means the rate per annum
                         (rounded up, if necessary, to the nearest
                         one-sixteenth of one percent) equal to the offered
                         quotation to the Bank in the London interbank
                         Eurodollar market for United States dollar deposits
                         for delivery on the date specified by the Borrower,
                         in the approximate amount of the loan and for the
                         period specified by the Borrower (which period must
                         be 30, 60, or 90 days), determined as of
                         approximately 11:00 A.M., London time, two business
                         days prior to the delivery date. If the Borrower
                         selects this LIBOR Rate Option, it must notify the
                         Bank at least two business days prior to the date on
                         which it wishes to receive the loan proceeds. Unless
                         the Borrower shall otherwise notify the Bank at least
                         two business days prior to the end of an Interest
                         Period, each advance bearing interest at the LIBOR
                         Rate shall continue to bear interest at the Base
                         Rate. The LIBOR Rate Option may only be selected for
                         minimum principal amounts of $100,000 or multiples
                         thereof.

        As used herein, "Base Rate" means the rate of interest established by
the Bank from time to time as its "base" or "prime" rate.

                Interest shall by payable monthly, commencing May 31, 1998 and
continuing on the same day of each succeeding month and also at maturity.



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                The Borrower may at any time prepay the Current Note in whole or
in part without premium or penalty; except that any prepayment of amounts based
on the LIBOR Rate where such prepayment is made on a day other than the final
day of an Interest Period shall require a prepayment penalty in an amount equal
to the difference between the amount of interest that would have been payable
for the remainder of the Interest Period at the rate then in effect and the
yield on a hypothetical U.S. Treasury Security that could be purchased on the
date of prepayment and maturing on the last day of the Interest Period.

         Unless prohibited by law, the undersigned agree(s) to pay all costs of
collection, including reasonable attorneys' fees and legal expenses, incurred by
the holder hereof in the event this Note is not duly paid. The holder hereof may
at any time renew this Note or extend its maturity date for any period and
release any security for, or any party to, this Note, all without notice to or
consent of and without releasing any accommodation maker, endorser or guarantor
from liability on this Note. Presentment or other demand for payment, notice of
dishonor and protest are hereby waived by the undersigned and each endorser and
guarantor. This Note shall be governed by the substantive laws of the State
named as part of the Bank's address above.

      This Note is issued pursuant to a Credit Agreement dated May ____, 1998,
between the Borrower and the Bank and is subject to the terms and conditions
thereof.


HEI, Inc.

By: 
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Its:
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