Set loan terms with larger payments at the end. Here's the information you'll need to have handy to complete your secured promissory note, installment with balloon final payment.Balloon Loan Payment Calculator. This calculator automatically figures the loan amortization period based on the desired balloon payment. An unsecured promissory note with amortized payments is a promise to pay back a loan when there's no collateral, and it'll be repaid in equal installments. The following is an example of promissory note which can be used to guide and direct eligibility decisions in which promissory notes are involved. By Mr. LINDSAY: Petition of Western Union Cable.