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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

    / /      Rule 13d-1(b)

    / /      Rule 13d-1(c)

    / /      Rule 13d-1(d)

    /x/      Rule 13d-2(a)

    *The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

    The information required in the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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CUSIP No.      671044-10-5    

(1)		Names of Reporting Persons. I.R.S. Identification Nos. of above persons (entities only).
		Chamberlain, Sally F.; Trustee and beneficiary
(2)		Check the Appropriate Box if a Member of a Group (See Instructions)
				(a)  / /
				(b)  / /
(3)		SEC Use Only
(4)		Citizenship or Place of Organization
		U.S.A.; California
Number of Shares Beneficially Owned by Each Reporting Person With:				(5)		Sole Voting Power
						965,853
				(6)		Shared Voting Power
				(7)		Sole Dispositive Power
						965,853
				(8)		Shared Dispositive Power
(9)		Aggregate Amount Beneficially Owned by Each Reporting Person
		965,853
(10)		Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)        / /
(11)		Percent of Class Represented by Amount in Row (9)
		9.9%
(12)		Type of Reporting Person (See Instructions)
		Trustee and beneficiary of the Edward P. Fleischer and Sally F. Fleischer Family Trust

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GENERAL INSTRUCTIONS

A.		Statements filed pursuant to Rule 13d-1(b) containing the information required by this schedule shall be filed not later than February 14 following the calendar year covered by the statement or within the time specified in Rules 13d-1(b)(2) and 13d2(c). Statements filed pursuant to Rule 13d-1(c) shall be filed within the time specified in Rules 13d-1(c), 13d-2(b) and 13d-2(d). Statements filed pursuant to Rule 13d-1(d) shall be filed not later than February 14 following the calendar year covered by the statement pursuant to Rules 13d-1(d) and 13d-2(b).
B.		Information contained in a form which is required to be filed by rules under section 13(f) (15 U.S.C. 78m(f)) for the same calendar year as that covered by a statement on this schedule may be incorporated by reference in response to any of the items of this schedule. If such information is incorporated by reference in this schedule, copies of the relevant pages of such form shall be filed as an exhibit to this schedule.
C.		The item numbers and captions of the items shall be included but the text of the items is to be omitted. The answers to the items shall be so prepared as to indicate clearly the coverage of the items without referring to the text of the items. Answer every item. If an item is inapplicable or the answer is in the negative, so state.

ITEM 1.

(a)		Name of Issuer
		OSI Systems, Inc.
(b)		Address of Issuer's Principal Executive Offices
		12525 Chadron Avenue, Hawthorne, CA 90250

ITEM 2.

(a)		Name of Person Filing
		Sally F. Chamberlain, Trustee and beneficiary
(b)		Address of Principal Business Office or, if none, Residence
		2404 Via Siena, La Jolla, CA 92037
(c)		Citizenship
		U.S.A.
(d)		Title of Class of Securities
		Common
(e)		CUSIP Number
		671044-10-5

ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO SECTIONS 240.13d-1(b) OR 240.13d-2(b) OR (c), CHECK WHETHER THE PERSON FILING IS A:

(a)		/ /		Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).
(b)		/ /		Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).
(c)		/ /		Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

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(d)		/ /		Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).
(e)		/ /		An investment adviser in accordance with section 240.13d-1(b)(1)(ii)(E).
(f)		/ /		An employee benefit plan or endowment fund in accordance with section 240.13d-1(b)(1)(ii)(F).
(g)		/ /		A parent holding company or control person in accordance with section 240.13d-1(b)(1)(ii)(G).
(h)		/ /		A savings association as defined in section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813).
(i)		/ /		A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3).
(j)		/ /		Group, in accordance with section 240.13d-1(b)(1)(ii)(J).

ITEM 4. OWNERSHIP

Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.

(a)		Amount beneficially owned:
		965,853
(b)		Percent of class:
		9.9%

(c)		Number of shares as to which the person has:
		(i)		Sole power to vote or to direct the vote
				965,853
		(ii)		Shared power to vote or to direct the vote
		(iii)		Sole power to dispose or to direct the disposition of
				965,853
		(iv)		Shared power to dispose or to direct the disposition of

Instruction. For computations regarding securities which represent a right to acquire an underlying security see §240.13d3(d)(1).

ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following.  / /

Instruction: Dissolution of a group requires a response to this item.

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ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON

If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than five percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.

ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY

If a parent holding company has filed this schedule, pursuant to Rule 13d-1(b)(ii)(G), so indicate under Item 3(g) and attach an exhibit stating the identity and the Item 3 classification of the relevant subsidiary. If a parent holding company has filed this schedule pursuant to Rule 13d-1(c) or Rule 13d-1(d), attach an exhibit stating the identification of the relevant subsidiary.

ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP

If a group has filed this schedule pursuant to §240.13d-1(b)(1)(ii)(J), so indicate under Item 3(j) and attach an exhibit stating the identity and Item 3 classification of each member of the group. If a group has filed this schedule pursuant to §240.13d-1(c) or §240.13d-1(d), attach an exhibit stating the identity of each member of the group.

ITEM 9. NOTICE OF DISSOLUTION OF GROUP

Notice of dissolution of a group may be furnished as an exhibit stating the date of the dissolution and that all further filings with respect to transactions in the security reported on will be filed, if required, by members of the group, in their individual capacity. See Item 5.

ITEM 10. CERTIFICATION

    (a)  The following certification is hereby included:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

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SIGNATURE

    After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

		December 22, 2001
		Date
		/s/ Sally F. Chamberlain
Sally F. Chamberlain, Trust beneficiary		Signature
		Sally F. Chamberlain, Trustee of the Edward P. Fleischer and Sally F. Fleischer Family Trust
		Name/Title

The original statement shall be signed by each person on whose behalf the statement is filed or his authorized representative. If the statement is signed on behalf of a person by his authorized representative other than an executive officer or general partner of the filing person, evidence of the representative's authority to sign on behalf of such person shall be filed with the statement, provided, however, that a power of attorney for this purpose which is already on file with the Commission may be incorporated by reference. The name and any title of each person who signs the statement shall be typed or printed beneath his signature.

NOTE: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties for whom copies are to be sent.

Attention: Intentional misstatements or omissions of fact constitute Federal criminal violations (See 18 U.S.C. 1001)

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GENERAL INSTRUCTIONS

ITEM 1.
ITEM 2.
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO SECTIONS 240.13d-1(b) OR 240.13d-2(b) OR (c), CHECK WHETHER THE PERSON FILING IS A
ITEM 4. OWNERSHIP
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
ITEM 9. NOTICE OF DISSOLUTION OF GROUP
ITEM 10. CERTIFICATION

SIGNATURE