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                                                               Exhibit 10 (bb)

                            SECURED PROMISSORY NOTE

$150,000.00                                                     March 1, 1998
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         FOR VALUE RECEIVED, RADIOSUNGROUP OF TEXAS, INC. ("Maker"), promises to
pay to the order of JOHN W. BIDDINGER, the sum of One Hundred and Fifty Thousand
and No/100 Dollars ($150,000.00), together with all interest thereon at the
fixed rate of TEN Percent (10%) per annum. Accrued interest shall be due and
payable on March 31, 1998 and on the final day of each successive calendar month
thereafter. Provided, however, on June 30, 1998, all principal and interest then
unpaid shall be finally due and payable.

         All amounts due under this Note are payable at par in lawful money of
the United States of America, at such place as the holder hereof (hereinafter
"Holder") may direct.

         A default shall occur under this Note if Maker fails to make the
payment required hereunder when due (time is of the essence hereof); or if Maker
becomes insolvent, or if Maker files bankruptcy or receivership proceedings or
has such proceedings filed against it; or if any property of Maker is subjected
to attachment, execution or other process; or if a default occurs under any
collateral document securing the indebtedness evidenced by this Note.

         Upon the occurrence of a default, as defined above. Holder may, at its
option, declare all principal and interest provided for under this Note, and any
other obligations of Maker to Holder, to be presently due and payable, and
Holder may enforce any remedies available to Holder under any documents securing
or evidencing, debts of Maker to Holder. Holder may waive any default before or
after it occurs and may restore this Note in full effect without impairing the
right to declare it due for a subsequent default. Following default, interest
shall accrue on the principal balance hereof at the maximum lawful rate.
Privilege is reserved to prepay this Note at any time. Provided, however, if
this Note is prepaid, regardless of the date of prepayment, such prepayment
shall be accompanied by such additional sums as may be required to ensure that
Holder receives a full four months interest on this Note. For example, if this
Note is prepaid on February 1, 1998 (and assuming the regular interest payment
was made as scheduled on March 31, 1998), the prepayment shall be accompanied by
an additional three months of interest as if the Note were paid in full on its
maturity date of June 30, 1998.

         Maker and all sureties, guarantors, endorsers and other parties to this
instrument hereby consent to any and all renewals, waivers, modifications, or
extensions of time (of any duration) that may be granted by Holder with respect
to this Note and severally waive demand, presentment, protest, notice of
dishonor, and all other notices which might otherwise be required by law. Holder
may release collateral securing this Note or parties liable therefor, in its
sole discretion.

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         Maker's performance under the terms of this Note is secured by, and
Maker hereby grants Holder a security interest in all of Maker's presently owned
and hereafter acquired personal property and fixtures including all accounts
receivable, equipment, goods, contract rights, general intangibles, furniture
and other property of Maker.

         Maker and all sureties, guarantors, endorsers and other parties hereto
agree to pay reasonable attorneys' fees and all court and other costs that
Holder may incur in the course of efforts to collect the debt evidenced hereby
or to protect Holder's interest in any collateral securing the same.

         If any provision of this Note should for any reason be invalid or
unenforceable, the other provisions hereof shall remain in full effect.

         Words used herein indicating gender or number shall be read as context
may require.

         The provisions of this Note may be amended or waived only by instrument
in writing signed by the Holder and Maker hereof and attached to this Note.

                                 RADIOSUNGROUP OF TEXAS, INC.




                                 By:__________________________
                                             James A. Hoetger
                                         Vice President, Finance

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For good and valuable consideration, SunGroup, Inc. hereby guarantees to Holder
the timely payment and performance of this Note. SunGroup, Inc.'s guarantee of
this Note is absolute and unconditional. SunGroup, Inc.'s guarantee of the
attached Note is irrevocable. This guarantee constitutes a guarantee of payment
and performance and not of collection.


Executed this 1st day of March, 1998.


SunGroup, Inc.


By:__________________________________
         James A. Hoetger
   Vice President/Chief Financial Officer