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                                                                   EXHIBIT 10.56

(PCTEL(TM) LOGO)
SIMPLIFYING MOBILITY

August 22, 2006

Steven Deppe
1250 Persimmon Dr.
St. Charles, Illinois 60174

Subject: Severance Benefits

Dear Steve:

The January, 2004 Employment Agreement that PCTEL ("Company") and you
("Employee)" signed as of January 2, 2004 provides that any alterations or
modifications to the terms of your employment can only be made in writing signed
by both parties. The January, 2004 Employment Agreement provided for certain
severance benefits that expired in January, 2006. I am pleased to extend to you
the below severance benefits which were approved by PCTEL, Inc.'s Board of
Directors earlier this year, and which will become effective upon your written
acceptance of this letter.

SEVERANCE BENEFITS

(a) Termination by Company Without Cause and Apart From Change of Control. If,
either prior to the occurrence of a Change of Control or after the twelve (12)
month period following a Change of Control, Employee's employment is terminated
(A) involuntarily by the Company for reasons other than Cause, death or
Disability, or (B) by Employee pursuant to a Voluntary Termination for Good
Reason, then Employee shall be entitled to receive the following benefits from
the Company:

     (i) Salary Continuation. Employee shall continue to receive Employee's then
current Base Salary for a period of twelve (12) months following Employee's
termination of employment by the Company for reasons other than Cause. All such
severance payments shall be paid in accordance with the Company's normal payroll
practices. Such continuation of Employee's Base Salary shall be in lieu of any
and all other benefits which Employee is entitled to receive on the date of
Employee's termination of employment pursuant to any Company severance and
benefit plans and practices or pursuant to other agreements with the Company.
Employee shall not be entitled to pro-rated payment of an annual bonus.

     (ii) Benefits. Employee shall receive one hundred percent (100%) of
Company-paid health, dental and vision insurance benefits at the same level of
coverage as was provided to Employee immediately prior to Employee's termination
of employment by the Company for reasons other than Cause ("Company-Paid
Coverage"). If such coverage included Employee's dependents immediately prior to
Employee's termination, such dependents shall also be covered at the Company's
expense. Provided that Employee elects COBRA within the required period,
Company-Paid Coverage shall continue until the earlier of (A) twelve (12) months
following the date of Employee's termination by the Company for reasons other
than Cause (the "Termination Date"), and (B) the date upon which Employee or
Employee's dependents become covered under another employer's group health,
dental and vision insurance benefit plans. For purposes of Title X of the
Consolidated Budget Reconciliation Act of 1985 ("COBRA"), the date of the
qualifying event for Employee and his or her dependents shall be the Termination
Date.

     (iii) Partial Accelerated Vesting. All equity awards from the Company then
held by Employee shall partially accelerate, or if Employee is then holding
unvested shares, Company's right to repurchase the then-unvested shares under
each such equity award shall partially lapse, with respect to the number of
shares under each such award that would have become vested or been released from
such repurchase right under each respective equity award if Employee's

   8725 West Higgins Road Suite 400 Chicago, IL 60631 / Tel: +1-773-243-3000 /
                      Fax: +1-773-243-3050 / www.pctel.com
                               PCTEL Inc. (C) 2006

<PAGE>

(PCTEL(TM) LOGO)
SIMPLIFYING MOBILITY

employment with the Company had continued for an additional twelve (12) months
following Employee's effective termination date for reasons other than Cause.

(b) Termination Following a Change of Control. If Employee's employment is
terminated within twelve (12) months following a Change of Control, the
severance and other benefits to which Employee is entitled, if any, shall be
governed by the Management Retention Agreement (which includes the definition of
Change of Control).

(c) Other Termination. If Employee's employment is terminated by the Company for
Cause, or by Employee for any reason, including death or Disability but other
than pursuant to a Voluntary Termination for Good Reason, then Employee shall
not be entitled to receive the severance and other benefits discussed above, but
may be eligible for those benefits (if any) as may then be required by law
established under the Company's severance and benefit plans and policies
existing at the time of such termination.

Section 409A Compliance. If the Company reasonably determines that Section 409A
of the Internal Revenue Code will result in the imposition of additional tax to
an earlier payment of the severance and other benefits provided in this letter
agreement, this letter agreement will be deemed amended to the extent necessary
to avoid the imposition of any such additional tax or income recognition prior
to actual payment to Employee under Section 409A and any temporary, proposed or
final Treasury Regulations and guidance promulgated thereunder, and the parties
agree to cooperate with each other and to take reasonably necessary steps in
this regard. The remaining severance benefits will be payable as provided above.

Definition of Terms:

The following terms referred to in this letter agreement shall have the
following meanings:

Base Salary. "Base Salary" shall mean an amount equal to the Employee's Company
annual salaried compensation.

Cause. "Cause" shall mean (i) an act of personal dishonesty taken by the
Employee in connection with his responsibilities as an Employee and intended to
result in substantial personal enrichment of the Employee, (ii) Employee being
convicted of a felony, (iii) a willful act by the Employee which constitutes
gross misconduct and which is injurious to the Company, (iv) following delivery
to the Employee of a written demand for performance from the Company which
describes the basis for the Company's reasonable belief that the Employee has
not substantially performed his duties, continued violations by the Employee of
the Employee's obligations to the Company which are demonstrably willful and
deliberate on the Employee's part.

Change of Control. "Change of Control" is as defined in the Management Retention
Agreement entered into between Company and Employee.

Disability. "Disability" shall mean that the Employee has been unable to perform
his Company duties as the result of his incapacity due to physical or mental
illness, and such inability, at least 26 weeks after its commencement, is
determined to be total and permanent by a physician selected by the Company or
its insurers and acceptable to the Employee or the Employee's legal
representative (such Agreement as to acceptability not to be unreasonably
withheld). Termination resulting from Disability may only be effected after at
least 30 days' written notice by the Company of its intention to terminate the
Employee's employment. In the event that the Employee resumes the performance of
substantially all of his duties hereunder before the termination of his
employment becomes effective, the notice of intent to terminate shall
automatically be deemed to have been revoked.

   8725 West Higgins Road Suite 400 Chicago, IL 60631 / Tel: +1-773-243-3000 /
                      Fax: +1-773-243-3050 / www.pctel.com
                               PCTEL Inc. (C) 2006

<PAGE>

(PCTEL(TM) LOGO)
SIMPLIFYING MOBILITY

Voluntary Termination for Good Reason. "Voluntary Termination for Good Reason"
shall mean the Employee voluntarily resigns after the occurrence of any of the
following: (i) a reduction by the Company in the Base Salary of the Employee as
in effect immediately prior to such reduction (other than a reduction that
generally applies to Company officers and/or managers); (ii) a material
reduction by the Company in the aggregate level of Employee benefits, including
bonuses, to which the Employee was entitled immediately prior to such reduction
with the result that the Employee's aggregate benefits package is materially
reduced (other than a reduction that generally applies to Company officers
and/or managers); (iii) the relocation of the Employee to a facility or a
location more than thirty-five (35) miles from the Employee's then present
location, without the Employee's express written consent; or (iv) any act or set
of facts or circumstances which would, under Illinois case law or statute
constitute a constructive termination of the Employee. For the avoidance of
doubt, the voluntary resignation by Employee after the occurrence of either of
the following shall not constitute grounds for a "Voluntary Termination for Good
Reason": (1) a material reduction of the Employee's duties, title, authority or
responsibilities, relative to the Employee's duties, title, authority or
responsibilities as in effect immediately prior to such reduction, in the
instance where, as a result of the Company being acquired and made part of a
larger entity, a the Senior Vice-President of a business unit of the Company,
for example, remains as such following a Change of Control, or, with good
business reasons, such as a restructure of the Company and/or its subsidiaries,
and/or a restructure of functions and/or reporting relationships; (2) a material
reduction, without good business reasons, of the facilities and perquisites
(including office space and location) available to the Employee immediately
prior to such reduction (other than a reduction that generally applies to
Company officers and/or managers).

Except as provided above, all remaining provisions of the entire employment
agreement between us shall continue in full force and effect.

Please indicate your acceptance to the above and foregoing by signing and
returning to me the enclosed copy of this letter. Thank you.

Very truly yours,


-------------------------------------
Martin H. Singer

Accept and Agree to the above and
foregoing this 22nd of August, 2006.


/s/ Steve Deppe
-------------------------------------
Steven Deppe

   8725 West Higgins Road Suite 400 Chicago, IL 60631 / Tel: +1-773-243-3000 /
                      Fax: +1-773-243-3050 / www.pctel.com
                               PCTEL Inc. (C) 2006