Exhibit 10.1

          American National Bank and Trust Company of Chicago

              REVOLVING LINE OF CREDIT NOTE (UNSECURED)

$4,000,000.00               Chicago, Illinois                 April 30,1998
                                                         Due: June 30, 1998

FOR VALUE RECEIVED, the undersigned jointly and severally if more than 
one) ("Borrower"), promises to pay to the order of American National Bank and 
Trust Company of Chicago ("Bank"), at its principal place of business in 
Chicago, Illinois or such other place as Bank may designate from time to time 
hereafter, the principal sum of FOUR MILLION AND NO/100 DOLLARS 
($4,000,000.00) or such lesser principal sum as may then be owed by Borrower 
to Bank hereunder, such payment to occur on June 30, 1998.  Borrower's 
obligations under this Note shall be defined and referred to herein as 
"Borrower's Liabilities".

This Note restates and replaces a Revolving Line of Credit Note in the 
principal amount of $4,000,000.00, dated December 31, 1996 executed by 
Borrower in favor of Bank (the "Prior Note") and is not a repayment or 
novation of the Prior Note.

Borrower may prepay all or part of the principal, together with accrued 
interest on the amount so prepaid, without penalty during the term of the 
Note. All prepayments shall be applied upon installments of the most remote 
maturity.

The principal amount of this Note is available to the Borrower on a 
revolving basis. The undersigned may borrow, repay and reborrow any amount, 
subject to the limitations contained in the Loan Agreement dated December 27, 
1995, as amended from time to time, executed by and between Corcom, Inc. and 
Bank (the "Loan Agreement"), provided that the total outstanding principal 
balance does not exceed the principal amount of this Note and that Borrower 
has complied with all the terms of this Note and the Loan Agreement.  The 
books and records of the Bank shall be determinative of the unpaid balance of 
this Note from time to time outstanding, absent manifest error.

Reference is hereby made to the Loan Agreement for a statement of the 
terms and conditions under which the loan evidenced hereby has been made, is 
to be repaid and for a statement of Bank's remedies upon the occurrence of an 
"Event of Default" as defined in the Loan Agreement. The terms and conditions 
of the Loan Agreement are incorporated herein by reference in their entirety.

Borrower's Liabilities unpaid from time to time shall bear interest 
(computed on the basis of a 360day year and actual days elapsed) from the date 
hereof until paid at a per annum rate at all times equal to the Bank's Base 
Rate or equivalent as announced or published publicly from time to time (the 
"Base Rate"). Therefore, interest shall be calculated for each day at 1/360th 
of the applicable per annum rate. The Base Rate is not indicative of the 
lowest or best rate offered by the Bank to any customer or group of customers. 
A change in the Base Rate shall constitute a corresponding change in the 
interest rate hereunder effective on and as of the date of such change in the 
Base Rate. The above notwithstanding, Borrower may elect to and cause all or a 
portion of the principal outstanding on this Note to bear interest at a daily 
rate equal to one and one-half percent (1.5) in excess of the London Interbank 
Offered Rate ("LIBOR") as announced by Bank from time to time pursuant to the 
terms and conditions of that certain London Interbank Offered Rate Borrowing 
Agreement between Borrower and Bank dated March 28,1995. Interest accruing 
prior to maturity shall be payable by Borrower to Bank monthly, or as billed 
by Bank to Borrower, at Bank's principal place of business, or at such other 
place as Bank may designate from time to time hereafter. All unpaid interest 
at maturity shall be paid with the principal amount of Borrower's Liabilities 
due hereunder.

Upon the occurrence of an Event of Default, as hereinafter defined, 
interest on the unpaid principal balance shall accrue at a rate equal to the

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then existing Base Rate plus three percent (3%) per annum.

Borrower agrees that in any action or proceeding instituted to collect 
or enforce collection of this Note, the amount recorded on the books and 
records of the Bank shall be prima facie evidence of the unpaid principal 
balance of the Note; provided that the failure of the Bank to record any 
advance hereunder shall not limit or otherwise affect the obligation of the 
Company to repay the principal amount owing on this Note together with accrued 
interest thereon.

If any payment becomes due and payable on a Saturday, Sunday or legal 
holiday under the laws of the State of Illinois, the due date of such payment 
shall be extended to the next business day. If the date for any payment of 
principal is thereby extended or is extended by operation of law or otherwise, 
interest thereon shall be payable at the then applicable rate of interest for 
such extended time.

Borrower warrants and represents to Bank that Borrower shall use the 
proceeds represented by this Note solely for the proper business purposes, and 
consistently with all applicable laws and statutes.

All of Bank's rights and remedies under this Note are cumulative and 
non-exclusive. The acceptance by Bank of any partial payment made hereunder 
after the time when any of Borrower's Liabilities become due and payable will 
not establish a custom, or waive any rights of Bank to enforce prompt payment 
thereof. Bank's failure to require strict performance by Borrower of any 
provision of this Note shall not waive, affect or diminish any right of Bank 
thereafter to demand strict compliance and performance therewith. Any waiver 
of an Event of Default hereunder shall not suspend, waive or affect any other 
Event of Default hereunder. Borrower and every endorser waive presentment, 
demand and protest and notice of presentment, protest, default, non-payment, 
maturity, release, compromise, settlement, extension or renewal of this Note, 
and hereby ratify and confirm whatever Bank may do in this regard. Borrower 
further waives and all notice or demand to which Bank might to entitled with 
respect to this Note by virtue of any applicable statute or law (to the extent 
permitted by law).

Borrower agrees to pay, upon Bank's demand therefore, any and all 
reasonable costs, fees and expenses (including attorneys' fees, costs and 
expenses) incurred in enforcing any of Bank's rights hereunder, and to the 
extent not paid the same shall become part of Borrower's Liabilities 
hereunder.

If any provision of this Note or the application thereof to any party 
or circumstance is held invalid or unenforceable, the remainder of this Note 
and the application thereof to other parties or circumstances will not be 
affected thereby, the provisions of this Note being severable in any such 
instance.

This Note is submitted by Borrower to Bank at Bank's principal place of 
business and shall be deemed to have been made there at. This Note shall be 
governed and controlled by the laws of the State of Illinois as to 
interpretation, validity, construction, affect, choice of law and in all other 
respects.

No modification, waiver, estoppel, amendment, discharge or change of 
this Note or any related instrument shall be valid unless the same is in 
writing and signed by the party against which the enforcement of such 
modification, waiver, estoppel, amendment, discharge or change is sought.

TO INDUCE BANK TO ACCEPT THIS NOTE, BORROWER IRREVOCABLY AGREES THAT, 
SUBJECT TO BANK'S SOLE AND ABSOLUTE ELECTION, ALL ACTIONS OR PROCEEDINGS IN 
ANY WAY, MANNER OR RESPECT, ARISING OUT OF OR FROM OR RELATED TO THIS NOTE 
SHALL BE LITIGATED IN COURTS HAVING SITUS WITHIN THE CITY OF CHICAGO, STATE OF 
ILLINOIS. BORROWER HEREBY CONSENTS TO THE JURISDICTION OF ANY LOCAL, STATE OR 
FEDERAL COURT LOCATED WITHIN SMD CITY AND STATE AND WAIVES ANY OBJECTION IT 
MAY HAVE BASED ON IMPROPER VENUE OR FORUM NON CONVENIENS TO THE CONDUCT OF ANY 
PROCEEDING INSTITUTED HEREUNDER.

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BORROWER AND BANK IRREVOCABLY WAIVE ANY RIGHT TO TRIAL BY JURY IN ANY 
ACTION OR PROCEEDING (I) TO ENFORCE OR DEFEND ANY RIGHTS UNDER OR IN 
CONNECTION WITH THIS NOTE OR ANY AMENDMENT, INSTRUMENT, DOCUMENT OR AGREEMENT 
DELWERED OR WHICH MAY IN THE FUTURE BE DELWERED IN CONNECTION HEREWITH OR (II) 
ARISING FROM ANY DISPUTE OR CONTROVERSY IN CONNECTION WITH OR RELATED TO THIS 
NOTE OR ANY SUCH AMENDMENT, INSTRUMENT, DOCUMENT OR AGREEMENT, AND AGREE THAT 
ANY SUCH ACTION OR PROCEEDING SHALL BE TRIED BEFORE A COURT AND NOT BEFORE A 
JURY.


Signed

CORCOM, INC.,
an Illinois corporation


s/s Thomas J. Buns
By: Thomas J. Buns, Vice President


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