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                                                                   EXHIBIT 10(G)
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                           KEITHLEY INSTRUMENTS, INC.

                        1992 DIRECTORS' STOCK OPTION PLAN


         1. PURPOSE. The purpose of this Directors' Stock Option Plan (the
"Plan") is to enable Keithley Instruments, Inc. (the "Company") to attract,
retain and reward directors of the Company and strengthen the mutuality of
interest between such directors and the Company's shareholders by offering such
directors options ("Options") to purchase shares of the Company's no par value
Common Shares ("Common Shares").

         2. GRANT AND ELIGIBILITY. All directors of the Company who are not
employees of the Company or not otherwise eligible to participate in other
employee benefit plans permitting a direct or indirect investment in Common
Shares ("Outside Directors") shall be granted Options under the Plan. From and
after the Effective Date, so long as the Plan remains in effect and has Common
Shares available for grants hereunder, each individual who qualifies as an
Outside Director at the close of any annual meeting of the shareholders of the
Company (an "Optionee") shall automatically be granted an Option to purchase
three hundred (300) Common Shares. In the event Common Shares are available for
grants hereunder, but the number of such Shares is insufficient to provide an
Outside Director with an Option to purchase three hundred (300) Common Shares,
such Outside Director shall receive an Option to purchase the lesser of (i) the
number of Common Shares remaining available for grant under the Plan; or (ii)
the number of Common Shares being granted to any other Outside Director
concurrently entitled to a grant of Options hereunder, so that Options are
granted to all such Outside Directors on a pro rata basis. The maximum aggregate
number of Common Shares available for issuance under the Plan is thirty thousand
(30,000); such Common Shares may be treasury shares or authorized but unissued
shares or a combination of the foregoing. If an Option granted under the Plan
shall expire, terminate or become forfeited for any reason other than its
exercise, the shares subject to, but not delivered under, such Option shall be
available for the grant of other Options pursuant to the Plan. The maximum
number of shares of Common Shares that an Outside Director shall be entitled to
receive as result of the exercise of Options granted under the Plan shall be
three thousand (3,000), subject to any adjustment required in accordance with
Section 6 hereof.

         3. TERM OF OPTION, EXERCISE AND TRANSFERABILITY. The term of each
Option granted under the Plan shall be ten years. An Optionee who has
continuously served as a director of the Company from the date of the grant of
an Option through the date of vesting may first exercise such Option after the
date of vesting for all or part of the number of Common Shares in accordance
with the Plan. For this purpose, the "date of vesting" for any Option granted
under the Plan shall be that date which is six months and one day after the
later to occur of: (i) the effective date of the Plan; or (ii) the date such
Optionee is elected as a director; or (iii) the date such Option is granted. An
Outside Director who resigns or is removed before the date of vesting for any
Options held by such Director shall forfeit such Options.

No Option shall be transferable by the Optionee other than by will or the laws
of descent and distribution. Options shall be exercisable during the Optionee's
lifetime only by an Optionee or by his or her legal guardian or legal
representative. Notwithstanding the first and second sentences of this paragraph
or the preceding paragraph, if any Optionee dies while holding unexercised
Options, any Option held by such Optionee at the time of his or her death shall
thereafter be exercised, to the extent such Option was exercisable at the time
of death, by the estate of the Optionee (acting through its fiduciary), within a
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period of one year from the date of such death regardless of the term of the
Option remaining at the Optionee's death.

         4. OPTION PRICE AND PAYMENT. The option price for each Common Share
purchasable under an Option shall be the fair market value of a Common Share on
the date such Option is granted in accordance with Section 2. The option price
shall be payable (i) in cash; (ii) by check acceptable to the Company; (iii) by
delivery of shares of the same class of stock subject to such Option; or (iv) a
combination of the above, so long as the sum of the fair market value of any
such cash, check or Common Shares equals the option price. The Company shall
have the right to require an Optionee who is entitled to receive Common Shares
pursuant to the exercise of an Option to pay to the Company the amount of any
taxes which the Company is required to withhold with respect to such Common
Shares. Such amount shall be payable (i) in cash; (ii) by check acceptable to
the Company; (iii) by delivery of shares of the same class of stock subject to
the Option; or (iv) a combination of the above.

         5. CHANGE IN CONTROL.

         (a) IMPACT OF EVENT. In the event of a "Change in Control" as defined
in Section 5(b), all Options granted under the Plan shall vest upon the later to
occur of (i) such Change in Control; or (ii) six months and one day after the
date of grant of such Options.

         (b) DEFINITION OF CHANGE IN CONTROL. For purposes of Section 5(a), a
"Change in Control" shall be deemed to have occurred if: (i) a tender offer
shall be made and consummated for the ownership of 25% or more of the
outstanding voting securities of the Company; (ii) the Company shall be merged
or consolidated with another corporation and, as a result of such merger or
consolidation, less than 75% of the outstanding voting securities of the
surviving or resulting corporation shall be owned in the aggregate by the former
shareholders of the Company as the same shall have existed immediately prior to
such merger or consolidation; (iii) the Company shall sell substantially all of
its assets to another corporation which is not a wholly owned subsidiary; or
(iv) a person, within the meaning of Section 3(a)(9) or of Section 13(d)(3) (as
in effect on the date hereof) of the Securities Exchange Act of 1934 (the
"Exchange Act"), shall acquire, other than by reason of inheritance, twenty-five
percent (25%) or more of the outstanding voting securities of the Company
(whether directly, indirectly, beneficially or of record). In making any such
determination, transfers made by a person to an affiliate of such person (as
determining by the Board of Directors of the Company), whether by gift, devise
or otherwise, shall not be taken into account. For purposes of this Plan,
ownership of voting securities shall take into account and shall include
ownership as determined by applying the provisions of Rule 13d-3(d)(1)(i) as in
effect on the date hereof pursuant to the Exchange Act.

         6. ADJUSTMENTS. (a) If, at any time subsequent to the date of adoption
of the Plan, the number of Common Shares are increased or decreased, or changed
into or exchanged for a different number or kind of shares of stock or other
securities of the Company or of another corporation (whether as a result of a
stock split, stock dividend, combination or exchange of shares, exchange for
other securities, reclassification, reorganization, redesignation, merger,
consolidation, recapitalization or otherwise): (i) there shall automatically be
substituted for each Common Share subject to an unexercised Option (in whole or
in part) granted under the Plan, the number and kind of shares of stock or other
securities into which each outstanding Common Share shall be changed or for
which each such Common Share shall be exchanged; and (ii) the option price per
Common Share or unit of securities shall be increased or decreased
proportionately so that the aggregate purchase price for the securities subject
to an Option shall remain the same as immediately prior to such event.

         (b) No adjustment pursuant to this Section 6 shall be required unless
such adjustment would require an increase or decrease of at least one percent
(1%) in such number or price; however, any

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adjustments which by reason of this Section 6 are not required to be made shall
be carried forward. Calculations under this Section 6 shall be made to the
nearest cent or to the nearest full share, as the case may be. Anything in this
Section 6 to the contrary notwithstanding, the Company shall be entitled to make
such reductions in the option price, in addition to those required by this
Section 6, as it, in its discretion shall determine to be advisable in order
that any stock dividends, subdivisions or splits of shares, distribution of
rights to purchase stock or securities, or a distribution of securities
convertible into or exchangeable for stock hereafter made by the Company to its
shareholders shall not be taxable.

         7. OTHER TERMS. Each grant of Options hereunder shall be evidenced by a
Shares Option Agreement in substantially the form attached hereto as Exhibit A.
When exercisable in accordance with Section 3, Options may be exercised, in
whole or in part, by giving written notice of exercise to the Company specifying
the number of Common Shares to be purchased. Such notice shall be accompanied by
payment of the option price of the Common Shares for which the Option is
exercised in accordance with Section 4.

         8. AMENDMENT. The Board of Directors of the Company (the "Board") may
at any time amend, modify, suspend or terminate this Plan. In no event, however,
without the approval of shareholders, shall any action of the Board of Directors
result in:

         (a)      Materially amending, modifying or altering the eligibility
                  requirements provided in Section 2 hereof;

         (b)      Increasing, except as provided in Section 2 hereof, the
                  maximum number of Common Shares available for purchase with
                  Options; or

         (c)      Increasing the benefits accruing to Optionees under this Plan;

except to conform this Plan and any agreements made hereunder to changes in the
Internal Revenue Code of 1986, as amended (the "Code") or governing law. In any
event, the Board of Directors shall not make any amendment or alteration which
would amend or alter the method by which the number or kind of securities to be
granted to any Optionee is determined, where such amendment or alteration is
made less than six months and one day after the previous such amendment or
alteration was made, unless such amendment or alteration is made to comport with
changes in the Code.

         9. TERMINATION OF PLAN. The Plan shall be terminated and no further
Options shall be granted hereunder as of the tenth (10th) anniversary of the
date this Plan is adopted by the Board. Options granted prior to such tenth
anniversary may extend beyond that date.

         10. COMPLIANCE WITH LAW AND APPROVAL OF REGULATORY BODY. No Option
shall be exercisable and no Common Shares will be delivered under this Plan
except in compliance with all applicable federal and state laws and regulations,
including, without limitation, compliance with applicable withholding tax
requirements, if any, and with the rules of all domestic stock exchanges on
which the Company's stock may be listed. Any stock certificates issued to
evidence Common Shares as to which an Option is exercised may bear such legends
and statements as the Company shall deem advisable to assure compliance with
federal and state laws and regulations; the Company may, if it deems
appropriate, condition its grant of any Options hereunder upon receipt of the
following investment representation from the Optionee:

         "I agree that any Common Shares of Keithley Instruments, Inc. which I
         may acquire by virtue of this Stock Option shall be acquired for
         investment purposes only and not with a view to distribution or resale,
         and may not be transferred, sold, assigned, pledged, hypothecated or

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         otherwise disposed of by me unless (i) a registration statement or
         post-effective amendment to a registration statement under the
         Securities Act of 1933, as amended, with respect to said Common Shares
         has become effective so as to permit the sale or other disposition of
         said shares by me; or (ii) there is presented to Keithley Instruments,
         Inc. an opinion of counsel satisfactory to Keithley Instruments, Inc.
         to the effect that the sale or other proposed disposition of said
         Common Shares by me may lawfully be made otherwise than pursuant to an
         effective registration statement or post-effective amendment to a
         registration statement relating to the said shares under the Securities
         Act of 1933, as amended."

No Option shall be exercisable, and no stock will be delivered under this Plan,
until the Company has obtained such consent or approval from the regulatory
body, federal or state, having jurisdiction over such matters as the Company may
deem advisable. In the case of the exercise of an Option by a person or estate
acquiring the right to exercise such Option by bequest or inheritance, the
Company may require reasonable evidence as to the ownership of such Option and
may require such consents and releases of taxing authorities as the Committee
may deem advisable.

         11. EFFECTIVE DATE. The Plan shall be effective as of February 8, 1992;
or if later, the date the Plan is approved by the Company's shareholders.

         12. GOVERNING LAW. The Plan, all options and actions taken thereunder
and any agreements relating thereto shall be governed by and controlled in
accordance with Ohio law.

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