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                                                                   EXHIBIT 10.19

SILICON VALLEY BANK

AMENDMENT TO PURCHASE AGREEMENT

SELLER: HARMONIC INC.
ADDRESS: 549 BALTIC WAY
         SUNNYVALE, CA 94089

DATE:    MARCH 28, 2003

         THIS AMENDMENT TO PURCHASE AGREEMENT is entered into between Silicon
Valley Bank ("Buyer") and the company named above ("Seller").

         The Parties agree to amend the Restated Non-Recourse Receivables
Purchase Agreement between them, dated September 25, 2001 (as amended, the
"Purchase Agreement"), as follows, effective as of the date hereof. (Capitalized
terms used but not defined in this Amendment, shall have the meanings set forth
in the Purchase Agreement.)

         1.       EXTENSION. The portion of Section 2.1 of the Purchase
Agreement which presently reads "(ii) buy any Purchased Receivable after April
1, 2003 (the 'Maturity Date')." is amended to read as follows:

         "(ii) buy any Purchased Receivable after March 27, 2004 (the 'Maturity
Date')."

         2.       SCHEDULE. The Schedule to the Purchase Agreement is replaced
by the Schedule attached hereto.

         3.       COLLECTION BY BUYER. Section 3.2 of the Purchase Agreement is
hereby amended in its entirety to read as follows:

                  "3.2  COLLECTION BY BUYER.

                            (a)     Seller shall, at any time and from time to
                  time, on Buyer's request, give written notice to each Account
                  Debtor that the Purchased Receivables have been sold,
                  transferred and assigned to Buyer, and directing that all
                  payments on the Purchased Receivable be made to the Buyer or
                  as the Buyer shall direct. Said written notice shall be on
                  Buyer's standard form.

                            (b)     At any time and from time to time, at
                  Buyer's option (but without obligation), Buyer shall have the
                  right to handle exclusively, and make all decisions with
                  respect to, the collection of the Purchased Receivables,
                  provided that, on request of Buyer, Seller shall take such

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             SILICON VALLEY BANK                 AMENDMENT TO PURCHASE AGREEMENT

                  actions as Buyer shall form time to time request, in order to
                  collect or assist in the collection of the Purchased
                  Receivables on behalf of Buyer. Until Buyer exercises its
                  right to handle exclusively the collection of the Purchased
                  Receivables, Seller shall collect the Purchased Receivables on
                  behalf of Buyer and will use diligence and commercially
                  reasonable means to collect Purchased Receivables on behalf of
                  Buyer. Buyer shall have no obligation to commence or prosecute
                  any litigation to collect any Purchased Receivable and all
                  actions and decisions as to the method and manner of
                  collection of Purchased Receivables shall be a matter of
                  Buyer's own discretion and business judgment.

                            (c)     If Seller is collecting the Purchased
                  Receivables under clause (b) above, Seller will remit all
                  payments and collections on Purchased Receivables to Buyer on
                  the last business day of each week (`Settlement Date')
                  starting the week after the Purchase Date, and, on each
                  Settlement Date Seller shall deliver to Buyer a written
                  report, in form acceptable to Buyer, of account activity
                  (including dates and amounts of payments) and changes with
                  respect to each Purchased Receivable.

                            (d)     If Buyer is collecting the Purchased
                  Receivables under clause (b) above, and for any reason any
                  payment on a Purchased Receivable, or any other proceeds of a
                  Purchased Receivable, shall come into Seller's possession or
                  control, Seller shall hold the same in trust for Buyer and
                  shall deliver the same to Buyer, in the same form as received,
                  with any necessary endorsements within one business day after
                  receipt of the same.

                            (e)     Seller shall deliver to Buyer any instrument
                  or chattel paper evidencing a Purchased Receivable.

                            (f)     Buyer shall have the right, at any time and
                  from time to time, to verify with the Account Debtors all
                  Purchased Receivables and all receivables offered to Buyer for
                  purchase, in Buyer's own name or in the name of the Seller, or
                  a nominee name, orally, in writing, by email, by other written
                  confirmation or any other means selected by Buyer in its
                  discretion.

                            (g)     Seller, at Buyer's request, shall commence
                  and prosecute legal proceedings for the collection of
                  Purchased Receivables in its name (as Buyer's assignee for
                  collection or enforcement) or, at Buyer's option, in Buyer's
                  name. Seller will not make Buyer a party to any litigation or
                  arbitration without Buyer's prior written consent."

         4.       REPRESENTATIONS TRUE. Seller represents and warrants to Buyer
that all representations and warranties set forth in the Purchase Agreement, as
amended hereby, are true and correct.

         5.       GENERAL PROVISIONS. This Amendment, the Purchase Agreement,
any prior written amendments to the Purchase Agreement signed by Buyer and
Seller, and the other written documents and agreements between Buyer and Seller
set forth in full all of the

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             SILICON VALLEY BANK                 AMENDMENT TO PURCHASE AGREEMENT

representations and agreements of the parties with respect to the subject matter
hereof and supersede all prior discussions, oral representations, oral
agreements and understandings between the parties with respect to the subject
hereof. Except as herein expressly amended, all of the terms and provisions of
the Purchase Agreement, and all other documents and agreements between Buyer and
Seller relating thereto shall continue in full force and effect and the same are
hereby ratified and confirmed.

SELLER:                                                    BUYER:

HARMONIC INC.                                              SILICON VALLEY BANK

BY /s/ Robin N. Dickson                                    BY /s/ Brad Leahy
  ----------------------------------                         -------------------
     PRESIDENT OR VICE PRESIDENT                           TITLE Vice President

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SCHEDULE DATED __________________
TO
NON-RECOURSE RECEIVABLES PURCHASE AGREEMENT
DATED AS OF SEPTEMBER 25, 2001

SELLER:                    Harmonic Inc.

BUYER:                     Silicon Valley Bank

PURCHASE DATE:    ______________________________________

DUE DATE:         _____ days from Purchase Date

TOTAL PURCHASED
RECEIVABLES:      $______________________(List of Receivables total)

DISCOUNT RATE:                      (a)     _________% (Buyer's most recently
                                    announced Prime Rate plus 1.50% per annum
                                    (for domestic and Canadian receivables with
                                    a discount period of 90 days or less)); and

                                    (b) _________% (Buyer's most recently
                                    announced Prime Rate plus 2.00% per
                                    annum(for foreign receivables with a
                                    discount period of 90 days or less)).

PRIME RATE:                 Prime Rate is Buyer's most recently announced "prime
                            rate," even if it is not Buyer's lowest rate.

PURCHASE PRICE:             $________________  (is _________% of the Total
                            Purchased Receivables which is the straight discount
                            of the Total Purchased Receivables discounted from
                            the Due Date to the Purchase Date at the Discount
                            Rate).

ADMINISTRATIVE FEE:         .25%

Seller warrants and represents that (a) its warranties and representations in
the Agreement are true and correct as of the date of this Schedule and (b) no
Event of Default has occurred under the Agreement.

SELLER:                                             BUYER:

HARMONIC, INC.                                      SILICON VALLEY BANK

By_________________________________                 By__________________________
Name_______________________________                 Name________________________
Title________________________________               Title_______________________

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