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EXHIBIT 10(Q)
                                   AMENDMENT NO. 3
                            TO LOAN AND SECURITY AGREEMENT


This Amendment dated as of December 20, 1995, is entered into by and between
Pico Macom, Inc., a Delaware corporation ("Debtor"), and Marine Midland Business
Loans, Inc., a Delaware corporation ("Secured Party"), with reference to the
following facts:

                                       RECITALS

A.   Secured Party is extending various secured financial accommodations to
     Debtor upon the terms of that certain Loan and Security Agreement
     dated as of May 25, 1994, as amended (the "Loan Agreement").

B.   Debtor and Secured Party desire to amend the Loan Agreement upon the
     terms and conditions set forth herein.

NOW THEREFORE, in consideration of the foregoing and for the other good and
valuable consideration, the receipt and adequacy of which is hereby acknowledged
by each party hereto, Debtor and Secured Party hereby agree as follows:

1.   DEFINED TERMS.  Unless otherwise specified herein, any capitalized
     terms defined in the Loan Agreement shall have the same respective
     meanings as used herein.

2.   MAXIMUM BORROWING CAPACITY.  With respect to the definition of
     "Borrowing Capacity" in Section 1.1 of the Loan Agreement and Item
     1(A) of the Schedule thereto, the maximum Borrowing Capacity shall be
     increased from $10,000,000.00 to $11,000,000.00.

3.   INVENTORY SUB-LINE.  With respect to Item 1(B)(ii) of the Schedule to
     the Loan Agreement, the sub-line for Advances against Eligible
     Inventory shall be increased from $4,500,000.00 to $5,500,000.00.

4.   FINANCIAL COVENANTS.  With respect to Section 10.15 of the Loan
     Agreement and Item 26 of the Schedule thereto, Debtor shall maintain
     the following levels of financial performance:

     (a)  Net Working Capital of not less than $3,500,000.00 at all times after
         the date of this Amendment;

     (b)  Working Capital Ratio of not less than 1.30:1 at all times after the
         date of this Amendment;

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     (c)  Tangible Net Worth of not less than $4,000,000.00 at all times after
          the date of this Amendment;

     (d)  Debt to Tangible Net Worth ratio of not more than 3.0:1 after the date
          of this Amendment; and

     (e)  Net Income After Taxes of not less than $750,000.00 during each fiscal
          year ending on or after December 31, 1995.

5.   TERM.  With respect to Section 13.13(a) of the Loan Agreement and Item 35
     of the schedule thereto, the term thereof is hereby extended to December
     31, 1996, and shall be automatically renewed for successive annual terms,
     subject to the termination provisions set forth therein.

6.   REPRESENTATIONS AND WARRANTIES.  Debtor reaffirms that the representations
     and warranties made to Secured Party in the Loan Agreement and other
     Transaction Documents are true and correct in all material respects as of
     the date of this Amendment as though made as of such date and after giving
     effect to this Amendment.  In addition, Debtor makes the following
     representations and warranties to Secured Party, which shall survive the
     execution of this Amendment:

     (a)  The execution, delivery and performance of this Amendment are within
          Debtor's powers, have been duly authorized by all necessary actions,
          have received all necessary governmental approvals, if any, and do not
          contravene any law or any contractual restrictions binding on Debtor.

     (b)  This Amendment is the legal, valid and binding obligation of Debtor,
          enforceable against Debtor in accordance with its terms, except as
          enforcement may be limited by bankruptcy, insolvency, moratorium and
          other similar laws affecting the rights or creditors generally.

     (c)  No event has occurred and is continuing, or would result from the
          execution, delivery and/or performance of this Amendment, which
          constitutes an Event of Default under the Loan Agreement or any other
          of the Transaction Documents, or would constitute such an Event of
          Default but for the requirement that notice be given or time elapse or
          both.

7.   CONTINUING EFFECT OF LOAN DOCUMENTS.  To the extent of any
     inconsistencies between the terms of this Amendment and the Loan
     Agreement, this Amendment shall govern.  In all other respects, the
     Loan Agreement and other Transaction Documents shall remain in full
     force and effect and are hereby ratified and confirmed.

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8.   REFERENCES.  Upon the effectiveness of this Amendment, each reference in
     any Transaction Document to "the Agreement", "hereunder", "herein", or of
     like import referring to the Loan Agreement shall mean and be a reference
     to the Loan Agreement as amended hereby.

9.   GOVERNING LAWS.  This Amendment, upon becoming effective, shall be deemed
     to be a contract made under, governed by, and subject to, and shall be
     construed in accordance with, the internal laws of the State of California.

10.  CONDITIONS PRECEDENT.  This Amendment shall become effective when, and only
     when, Secured Party shall have received a counterpart of this Amendment
     duly executed by Debtor and acknowledged by the guarantor indicated
     hereinbelow, together with such other documents, instruments or agreements
     as Secured Party or its legal counsel may reasonably request.

IN WITNESS WHEREOF, the parties hereto, intending to be legally bound hereby,
have executed this Amendment as of the date first set forth above, to become
effective in the manner set forth above.

                                       PICO MACOM, INC.


                                       By     Joseph T. Kingsley
                                            ----------------------------------

                                       Title  V.P. Finance
                                            ----------------------------------


                                       MARINE MIDLAND BUSINESS LOANS, INC.


                                       By     William Field
                                            ----------------------------------

                                       Title  Vice President
                                            ----------------------------------

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