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                                                                           10.60

                                   PROMISSORY NOTE


          FOR VALUE RECEIVED, the undersigned, XIT Corporation, a New Jersey
corporation ("XIT") promises to pay to Arnold Circuits, Inc., a California
corporation (the "Lender") Three Hundred Fifty Thousand and 00/100 Dollars
($350,000.00), without interest, as follows:

          1.   ASSET PURCHASE AGREEMENT.  This Note evidences a loan in the 
amount of $350,000.00 (the "Loan") made pursuant to the terms of an Asset 
Purchase Agreement dated as January 9, 1998, as amended by the March 31, 1998 
Addendum No. 1 to Asset Purchase Agreement, by and between, INTER ALIA, XCEL 
Arnold Circuits, Inc. ("Seller"), XIT and the Lender (the "Asset Purchase 
Agreement"), pursuant to which Lender has acquired certain assets of Seller.  
Capitalized terms used herein and not otherwise defined shall have the 
meaning ascribed thereto in the Asset Purchase Agreement.  

          2.   TERM; PAYMENT.  The entire principal amount of this Note shall 
be paid upon the earlier of the following:  1) within three (3) business days 
of the closing of the refinancing by XIT and its affiliates of their existing 
term loans and lines of credit, or 2) May 31, 1998.  If the refinancing is 
not concluded and the Note is not repaid by May 31, 1998, it shall thereupon 
become payable upon demand.

          3.   PREPAYMENTS.  This Note may be prepaid, in whole or in part, 
by XIT at any time, and from time to time, and without penalty, provided that 
no prepayment may be made by XIT until the Lender or any Holder of the Note 
shall have received a written notice of the prepayment not less than ten (10) 
days prior to such prepayment.  

          4.   DEFAULT.  XIT shall be in default under this Note upon the 
occurrence of: (i) any of the events specified in Section 4(a) hereof and the 
failure to cure such default within ten (10) days after receipt of written 
notice thereof from the Lender; or (ii) any of the events specified in 
Section 4(b) hereof (any of the foregoing being an "Event of Default"):

               (a)  Failure to make the principal payment required under this 
          Note on the due date of such payment; or

               (b)  Insolvency of, business failure of, or an assignment for 
          the benefit of creditors by or the filing of a petition under 
          bankruptcy, insolvency or debtor's relief law, or for any 
          readjustment of indebtedness, composition or extension by XIT, 
          or commenced against XIT which is not discharged within 
          sixty (60) days.

          5.   REMEDIES UPON EVENT OF DEFAULT.  Upon the occurrence of an 
Event of Default specified in clauses (a) or (b) of Section 4, the Lender may 
declare the entire amount of the Loan immediately accelerated, due and 
payable.

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          6.   CHANGES; PARTIES.  This Note can only be changed by an 
agreement in writing signed by XIT and the Lender.  This Note shall inure to 
the benefit of and be binding upon XIT and the Lender and their respective 
successors and assigns.

          7.   WAIVER OF PRESENTMENT.  Except as otherwise set forth in this 
Note, XIT and every endorser of this Note or the obligation represented 
hereby waive presentment, demand, notice, protest and all other demands and 
notices in connection with the delivery, acceptance, performance, default or 
enforcement of this Note, assent to any extension or postponement of time of 
payment or any other indulgence and to the addition or release of any other 
party primarily or secondarily liable.

          8.   NOTE TRANSFERABLE.  This Note is fully transferrable by 
Lender, without the consent of or notice to, XIT.

          9.   GOVERNING LAW.  THIS NOTE SHALL BE CONSTRUED ACCORDING TO THE 
LAWS OF THE STATE OF CALIFORNIA AND XIT AND THE LENDER BY ACCEPTANCE HEREOF 
CONSENT TO THE JURISDICTION OF THE FEDERAL AND STATE COURTS OF THE STATE OF 
CALIFORNIA TO DETERMINE ANY QUESTIONS OF FACT OR LAW ARISING UNDER THIS NOTE. 
 XIT AND LENDER CONSENT TO AND CONFER PERSONAL JURISDICTION ON THE FEDERAL 
AND STATE COURTS OF CALIFORNIA, AND EXPRESSLY WAIVE ANY OBJECTIONS AS TO 
VENUE IN ANY OF SUCH COURTS, AND AGREE THAT SERVICE OF PROCESS MAY BE MADE BY 
MAILING A COPY OF THE SUMMONS TO ITS RESPECTIVE ADDRESS.

          IN WITNESS WHEREOF, XIT Corporation has executed this Note as of 
the day and year set forth below.

Dated: March 31, 1998
                                  XIT CORPORATION


                                  By: /s/ Carmine T. Oliva 
                                     -----------------------
                                  Name: Carmine T. Oliva   
                                       ---------------------
                                  Title: President and Chief Executive Officer:
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