Exhibit 10.2

PROMISSORY NOTE

$10,000,000.00

June 16, 2005

TradeStation Securities, Inc.
8050 S.W. 10th Street, Suite 2000
Plantation, Florida 33324
(Hereinafter referred to as “Borrower”)

Wachovia Bank, National Association
225 Water Street
Jacksonville, Florida 32202
(Hereinafter referred to as “Bank”)

Borrower promises to pay to the order of Bank, in lawful money of the United
States of America, at its office indicated above or wherever else in the United
States of America Bank may specify, the sum of Ten Million and No/100 Dollars
($10,000,000.00) or such sum as may be advanced and outstanding from time to
time, with interest on the unpaid principal balance at the rate and on the terms
provided in this Promissory Note (including all renewals, extensions or
modifications hereof, this “Note”).

LOAN AGREEMENT. This Note is subject to the provisions of that certain Loan
Agreement between Bank and Borrower of even date herewith, as modified from time
to time (the “Loan Agreement”).

LINE OF CREDIT. Borrower may borrow, repay and reborrow, and, upon the request
of Borrower, Bank shall advance and readvance under this Note from time to time
until the maturity hereof (each an “Advance” and together the “Advances”), so
long as the total principal balance outstanding under this Note at any one time
does not exceed the principal amount stated on the face of this Note, subject to
the limitations described in the Loan Agreement; and further provided that the
outstanding Advances are repaid to a maximum outstanding balance of $1,000 for 5
(consecutive or non-consecutive) days each month. Bank’s obligation to make
Advances under this Note shall terminate if a demand for payment is made under
this Note or if a Default (as defined below) occurs or, in any event, on the
first anniversary hereof unless renewed or extended by Bank in writing upon such
terms then satisfactory to Bank. As of the date of each proposed Advance,
Borrower shall be deemed to represent that each representation made in the Loan
Documents is true as of such date in all material respects.

If Borrower subscribes to Bank’s cash management services and such services are
applicable to this line of credit, the terms of such service shall control the
manner in which funds are transferred between the applicable demand deposit
account and the line of credit for credit or debit to the line of credit.

USE OF PROCEEDS. Borrower shall use the proceeds of the loan(s) evidenced by
this Note for the commercial purposes of Borrower, as follows: for working
capital.

INTEREST RATE. Interest shall accrue on the unpaid principal balance of this
Note from the date hereof at the LIBOR Market Index Rate plus 1.70%, as that
rate may change from day to day in accordance with changes in the LIBOR Market
Index Rate (“Interest Rate”). “LIBOR Market Index Rate”, for any day, means the
rate for 1 month U.S. dollar deposits as reported on Telerate page 3750 as of
11:00 a.m., London time, on such day, or if such day is not a London business
day, then the immediately preceding London business day (or if not so reported,
then as determined by Bank from another recognized source or interbank
quotation).

DEFAULT RATE. In addition to all other rights contained in this Note, if a
Default (as defined herein) occurs and as long as a Default continues, all
outstanding Obligations, other than Obligations under any swap agreements (as
defined in 11 U.S.C. § 101, as in effect from time to time) between Borrower and
Bank or its affiliates, shall bear interest at the Interest Rate plus 3%
(“Default Rate”). The Default Rate shall also apply from acceleration until the
Obligations or any judgment thereon is paid in full.

INTEREST AND FEE(S) COMPUTATION (ACTUAL/360). Interest and fees, if any, shall
be computed on the basis of a 360-day year for the actual number of days in the
applicable period (“Actual/360 Computation”). The Actual/360 Computation
determines the annual effective interest yield by taking the stated
(nominal) rate for a year’s period and then dividing said rate by 360 to
determine the daily periodic rate to be applied for each day in the applicable
period. Application of the Actual/360 Computation produces an annualized
effective rate exceeding the nominal rate.

REPAYMENT TERMS. This Note shall be due and payable in consecutive monthly
payments of accrued interest only, commencing on June 30, 2005, and continuing
on the same day of each month thereafter until fully paid. In any event, all
principal and accrued interest shall be due and payable on demand but in no
event later than June 16, 2006, unless this Note is extended as provided above.

AUTOMATIC DEBIT OF CHECKING ACCOUNT FOR LOAN PAYMENT. Borrower authorizes Bank
to debit demand deposit account number 2000025742451 or any other account with
Bank (routing number 063000021) designated in writing by Borrower, beginning
June 30, 2005 for any payments due under this Note. Borrower further certifies
that Borrower holds legitimate ownership of this account and preauthorizes this
periodic debit as part of its right under said ownership.

UNUSED FEE. Borrower shall pay Bank a quarterly unused fee equal to .25% per
annum on the average daily unused available principal under this Note for the
preceding calendar quarter or portion thereof. However, should Borrower and/or
TradeStation Group, Inc. (“Guarantor”) (and/or other subsidiaries or affiliates
of Guarantor) maintain in the aggregate, on average, deposits with Bank equal to
or greater than $1,000,000, then, with respect to all such periods, Bank shall
waive the unused fee above in full in the first full year of the commitment
evidenced by this Note. Thereafter, should this Note be renewed, the unused fee
shall be waived on a going forward basis if the sum of such deposits, coupled
with any other investment instruments offered by Bank, in the aggregate total on
average $10,000,000. Average deposits shall be computed on a quarterly basis.

APPLICATION OF PAYMENTS. Monies received by Bank from any source for application
toward payment of the Obligations shall be applied to accrued interest and then
to principal. If a Default occurs, monies may be applied to the Obligations in
any manner or order deemed appropriate by Bank.

If any payment received by Bank under this Note or other Loan Documents is
rescinded, avoided or for any reason returned by Bank because of any adverse
claim or threatened action, the returned payment shall remain payable as an
obligation of all persons liable under this Note or other Loan Documents as
though such payment had not been made.

DEFINITIONS. Loan Documents. The term “Loan Documents” as used in this Note and
the other Loan Documents, refers to all documents executed in connection with
and related to the loan evidenced by this Note, and may include, without
limitation, a loan agreement, this Note, a guaranty agreement, and any renewals
or modifications, whenever any of the foregoing are executed, but does not
include swap agreements (as defined in 11 U.S.C. § 101, as in effect from time
to time). Obligations. The term “Obligations”, as used in this Note and the
other Loan Documents, refers to any and all indebtedness and other obligations
under this Note, all other material obligations under any other Loan
Document(s), and all obligations under any swap agreements (as defined in 11
U.S.C. § 101, as in effect from time to time) between Borrower and Bank, or its
affiliates, whenever executed. Certain Other Terms. All terms that are used but
not otherwise defined in any of the Loan Documents shall have the definitions
provided in the Uniform Commercial Code.

LATE CHARGE. If any payments are not timely made, Borrower shall also pay to
Bank a late charge equal to 5% of each payment past due for 10 or more days.
This late charge shall not apply to payments

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due at maturity or by acceleration hereof, unless such late payment is in an
amount not greater than the highest periodic payment due hereunder.

Acceptance by Bank of any late payment without an accompanying late charge shall
not be deemed a waiver of Bank’s right to collect such late charge or to collect
a late charge for any subsequent late payment received.

ATTORNEYS’ FEES AND OTHER COLLECTION COSTS. Borrower shall pay all of Bank’s
reasonable expenses incurred to enforce or collect any of the Obligations
including, without limitation, reasonable arbitration, paralegals’, attorneys’
and experts’ fees and expenses, whether incurred without the commencement of a
suit, in any trial, arbitration, or administrative proceeding, or in any
appellate or bankruptcy proceeding.

USURY. If at any time the effective interest rate under this Note would, but for
this paragraph, exceed the maximum lawful rate, the effective interest rate
under this Note shall be the maximum lawful rate, and any amount received by
Bank in excess of such rate shall be applied to principal and then to fees and
expenses, or, if no such amounts are owing, returned to Borrower.

DEFAULT. If any of the following occurs, a default (“Default”) under this Note
shall exist: Nonpayment; Nonperformance. The failure of timely payment or
performance of the Obligations under this Note or a Default under any other Loan
Documents with respect to which any non-payment related failure to perform is
not cured within ten (10) days following written notice to Borrower (the right
to cure may not be utilized more than once in any twelve (12) month period).
False Warranty. A warranty or representation made or deemed made in the Loan
Documents or furnished Bank in connection with the loan evidenced by this Note
proves materially false and is materially adverse to Borrower, or, if of a
continuing nature, becomes materially false and is materially adverse to
Borrower. Cessation; Bankruptcy. The dissolution of, termination of existence
of, loss of good standing status by, appointment of a receiver for, assignment
for the benefit of creditors of, or commencement of any bankruptcy or insolvency
proceeding by or against Borrower, or any party to the Loan Documents
(“Affiliate” shall have the meaning as defined in 11 U.S.C. § 101, as in effect
from time to time, except that the term “Borrower” shall be substituted for the
term “Debtor” therein; “Subsidiary” shall mean any business in which Borrower
holds, directly or indirectly, a controlling interest). Material Capital
Structure or Business Alteration. Without prior written consent of Bank, (i) a
material alteration in the kind or type of Borrower’s business; (ii) the sale of
substantially all of the business or assets of Borrower, or any guarantor, or a
material portion (10% or more) of such business or assets if such a sale is
outside the ordinary course of business of Borrower, or any guarantor, or more
than 50% of the outstanding stock or voting power of or in any such entity in a
single transaction or a series of transactions; (iii) the acquisition by
Borrower of substantially all of the business or assets or more than 50% of the
outstanding stock or voting power of any other entity; provided that Borrower
may make one such acquistion during the term of this Note without the written
consent of Bank if the net book value of such business or assets is less than
25% of Borrower’s net book value; or (iv) should any Borrower or any of
Borrower’s Subsidiaries or Affiliates or any guarantor enter into any merger or
consolidation with an unrelated third party; provided that Borrower may enter
into one such merger or consolidation during the term of this Note without the
written consent of Bank if the net book value of the other entity is less than
25% of Borrower’s net book value. Material Adverse Change. Bank determines in
good faith, exercising reasonable discretion, that the prospects for payment or
performance of the Obligations are materially impaired or there has occurred a
material adverse change in the business or prospects of Borrower, financial or
otherwise.

REMEDIES UPON DEFAULT. If a Default occurs under this Note or any Loan
Documents, Bank may at any time thereafter, take the following actions:
Acceleration Upon Default. Accelerate the maturity of this Note and, at Bank’s
option, any or all other Obligations, other than Obligations under any swap
agreements (as defined in 11 U.S.C. § 101, as in effect from time to time)
between Borrower and Bank, or its affiliates, which shall be due in accordance
with and governed by the provisions of said swap agreements; whereupon this Note
and the accelerated Obligations shall be immediately due and payable; provided,
however, if the Default is based upon a bankruptcy or insolvency proceeding
commenced by or against Borrower or any guarantor or endorser of this Note, all
Obligations (other than Obligations under

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any swap agreement as referenced above) shall automatically and immediately be
due and payable. Cumulative. Exercise any rights and remedies as provided under
the Note and other Loan Documents, or as provided by law or equity.

FINANCIAL AND OTHER INFORMATION. Borrower shall deliver to Bank its parent
company’s annual reports on Form 10-K and quarterly reports on Form 10-Q
promptly following filing thereof with the Securities and Exchange Commission.
Such information shall be true, complete, and accurate in all material respects.

WAIVERS AND AMENDMENTS. No waivers, amendments or modifications of this Note and
other Loan Documents shall be valid unless in writing and signed by an officer
of Bank. No waiver by Bank of any Default shall operate as a waiver of any other
Default or the same Default on a future occasion. Neither the failure nor any
delay on the part of Bank in exercising any right, power, or remedy under this
Note and other Loan Documents shall operate as a waiver thereof, nor shall a
single or partial exercise thereof preclude any other or further exercise
thereof or the exercise of any other right, power or remedy.

Except to the extent otherwise provided by the Loan Documents or prohibited by
law, each Borrower and each other person liable under this Note waives
presentment, protest, notice of dishonor, demand for payment, notice of
intention to accelerate maturity, notice of acceleration of maturity, notice of
sale and all other notices of any kind. Further, each agrees that Bank may
extend, or renew this Note, all without notice to or consent of Borrower, and
without affecting the liability of Borrower.

MISCELLANEOUS PROVISIONS. Assignment. This Note and the other Loan Documents
shall inure to the benefit of and be binding upon the parties and their
respective heirs, legal representatives, successors and assigns. Bank’s
interests in and rights under this Note and the other Loan Documents are freely
assignable, in whole or in part, by Bank. In addition, nothing in this Note or
any of the other Loan Documents shall prohibit Bank from pledging or assigning
this Note or any of the other Loan Documents or any interest therein to any
Federal Reserve Bank. Borrower shall not assign its rights and interest
hereunder without the prior written consent of Bank, and any attempt by Borrower
to assign without Bank’s prior written consent is null and void. Any assignment
shall not release Borrower from the Obligations. Applicable Law; Conflict
Between Documents. This Note and, unless otherwise provided in any other Loan
Document, the other Loan Documents shall be governed by and construed under the
laws of the state named in Bank’s address on the first page hereof without
regard to that state’s conflict of laws principles. If the terms of this Note
should conflict with the terms of any loan agreement or any commitment letter
that survives closing, the terms of this Note shall control. Borrower’s
Accounts. Except as prohibited by law, Borrower grants Bank a security interest
in all of Borrower’s accounts with Bank and any of its affiliates. Swap
Agreements. All swap agreements (as defined in 11 U.S.C. § 101, as in effect
from time to time), if any, between Borrower and Bank or its affiliates are
independent agreements governed by the written provisions of said swap
agreements, which will remain in full force and effect, unaffected by any
repayment, prepayment, acceleration, reduction, increase or change in the terms
of this Note, except as otherwise expressly provided in said written swap
agreements, and any payoff statement from Bank relating to this Note shall not
apply to said swap agreements unless expressly referred to in such payoff
statement. Jurisdiction. Borrower irrevocably agrees to non-exclusive personal
jurisdiction in the state named in Bank’s address on the first page hereof.
Severability. If any provision of this Note or of the other Loan Documents shall
be prohibited or invalid under applicable law, such provision shall be
ineffective but only to the extent of such prohibition or invalidity, without
invalidating the remainder of such provision or the remaining provisions of this
Note or other such document. Notices. Any notices, demands or similar
communications to Borrower shall be sufficiently given, if in writing and mailed
or delivered to the Borrower’s address shown above or such other address as
provided hereunder, and to Bank, if in writing and mailed or delivered to
Wachovia Bank, National Association, Mail Code VA7628, P. O. Box 13327, Roanoke,
VA 24040 or Wachovia Bank, National Association, Mail Code VA7628, 10 South
Jefferson Street, Roanoke, VA 24011 or such other address as Bank may specify in
writing from time to time. Notices to Bank must include the mail code. In the
event that Borrower changes Borrower’s address at any time prior to the date the
Obligations are paid in full, Borrower agrees to promptly give written notice of
said change of address by registered or certified mail, return receipt
requested, all charges prepaid. Plural; Captions. All

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references in the Loan Documents to Borrower, guarantor, person, document or
other nouns of reference mean both the singular and plural form, as the case may
be, and the term “person” shall mean any individual, person or entity. The
captions contained in the Loan Documents are inserted for convenience only and
shall not affect the meaning or interpretation of the Loan Documents. Advances.
Bank may, in its sole discretion, make other advances which shall be deemed to
be advances under this Note, even though the stated principal amount of this
Note may be exceeded as a result thereof. Posting of Payments. All payments
received during normal banking hours after 2:00 p.m. local time at the office of
Bank first shown above shall be deemed received at the opening of the next
banking day. Joint and Several Obligations. If there is more than one Borrower,
each is jointly and severally obligated. Fees and Taxes. Borrower shall promptly
pay all documentary, intangible recordation and/or similar taxes on this
transaction whether assessed at closing or arising from time to time. LIMITATION
ON LIABILITY; WAIVER OF PUNITIVE DAMAGES. EACH OF THE PARTIES HERETO, INCLUDING
BANK BY ACCEPTANCE HEREOF, AGREES THAT IN ANY JUDICIAL, MEDIATION OR ARBITRATION
PROCEEDING OR ANY CLAIM OR CONTROVERSY BETWEEN OR AMONG THEM THAT MAY ARISE OUT
OF OR BE IN ANY WAY CONNECTED WITH THIS NOTE, THE LOAN DOCUMENTS OR ANY OTHER
AGREEMENT OR DOCUMENT BETWEEN OR AMONG THEM OR THE OBLIGATIONS EVIDENCED HEREBY
OR RELATED HERETO, IN NO EVENT SHALL ANY PARTY HAVE A REMEDY OF, OR BE LIABLE TO
THE OTHER FOR, (1) INDIRECT, SPECIAL OR CONSEQUENTIAL DAMAGES OR (2) PUNITIVE OR
EXEMPLARY DAMAGES. EACH OF THE PARTIES HEREBY EXPRESSLY WAIVES ANY RIGHT OR
CLAIM TO PUNITIVE OR EXEMPLARY DAMAGES THEY MAY HAVE OR WHICH MAY ARISE IN THE
FUTURE IN CONNECTION WITH ANY SUCH PROCEEDING, CLAIM OR CONTROVERSY, WHETHER THE
SAME IS RESOLVED BY ARBITRATION, MEDIATION, JUDICIALLY OR OTHERWISE. Patriot Act
Notice. To help fight the funding of terrorism and money laundering activities,
Federal law requires all financial institutions to obtain, verify, and record
information that identifies each person who opens an account. For purposes of
this section, account shall be understood to include loan accounts. FINAL
AGREEMENT. This Note and the other Loan Documents represent the final agreement
between the parties and may not be contradicted by evidence of prior,
contemporaneous or subsequent oral agreements of the parties. There are no
unwritten oral agreements between the parties.

WAIVER OF JURY TRIAL. TO THE EXTENT PERMITTED BY APPLICABLE LAW, EACH OF
BORROWER BY EXECUTION HEREOF AND BANK BY ACCEPTANCE HEREOF, KNOWINGLY,
VOLUNTARILY AND INTENTIONALLY WAIVES ANY RIGHT EACH MAY HAVE TO A TRIAL BY JURY
IN RESPECT OF ANY LITIGATION BASED ON, OR ARISING OUT OF, UNDER OR IN CONNECTION
WITH THIS NOTE, THE LOAN DOCUMENTS OR ANY AGREEMENT CONTEMPLATED TO BE EXECUTED
IN CONNECTION WITH THIS NOTE, OR ANY COURSE OF CONDUCT, COURSE OF DEALING,
STATEMENTS (WHETHER VERBAL OR WRITTEN) OR ACTIONS OF ANY PARTY WITH RESPECT
HERETO. THIS PROVISION IS A MATERIAL INDUCEMENT TO BANK TO ACCEPT THIS NOTE.
EACH OF THE PARTIES AGREES THAT THE TERMS HEREOF SHALL SUPERSEDE AND REPLACE ANY
PRIOR AGREEMENT RELATED TO ARBITRATION OF DISPUTES BETWEEN THE PARTIES CONTAINED
IN ANY LOAN DOCUMENT OR ANY OTHER DOCUMENT OR AGREEMENT HERETOFORE EXECUTED IN
CONNECTION WITH, RELATED TO OR BEING REPLACED, SUPPLEMENTED, EXTENDED OR
MODIFIED BY, THIS NOTE.

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IN WITNESS WHEREOF, Borrower, on the day and year first above written, has
caused this Note to be executed under seal.

TradeStation Securities, Inc.

By: /s/ Joseph Nikolson

      Name: Joseph Nikolson
Title: President

Address:
8050 S.W. 10th Street, Suite 2000
Plantation, Florida 33324

Tracking #: 1
CAT — Deal # 305919 Facility ID 276516

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