Annual report pursuant to Section 13 and 15(d)

Note 1 - Summary of Significant Accounting Policies (Details Textual)

v3.22.2.2
Note 1 - Summary of Significant Accounting Policies (Details Textual)
12 Months Ended
Jan. 27, 2022
USD ($)
Sep. 30, 2022
USD ($)
$ / shares
shares
Sep. 30, 2021
USD ($)
$ / shares
shares
Sep. 30, 2020
USD ($)
shares
Apr. 25, 2017
USD ($)
Depreciation, Total | $   $ 2,647,000 $ 1,699,000 $ 1,944,000  
Goodwill, Impairment Loss | $   $ 0 0 0  
Number of Patents Granted   36      
Amortization of Intangible Assets | $   $ 766,000 602,000 478,000  
Impairment, Long-Lived Asset, Held-for-Use, Total | $   0 0 0  
Unrecognized Tax Benefits, Ending Balance | $   0 $ 0 $ 0  
Stock Repurchase Program, Increase in Authorized Amount | $ $ 10,000,000        
Stock Repurchase Program, Authorized Amount | $ $ 22,000,000 $ 22,000,000     $ 12,000,000
Stock Repurchased, Cumulative (in shares)   565,590      
Stock Repurchased, Value, Cumulative | $   $ 7,019,000      
Stock Repurchase Program, Remaining Authorized Repurchase Amount | $   $ 14,981,000      
Stock Repurchased During Period, Shares (in shares)   13,292 11,754 10,038  
Common Stock, Shares Authorized (in shares)   50,000,000 50,000,000    
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares   $ 0.01 $ 0.01    
Preferred Stock, Shares Authorized (in shares)   500,000 500,000    
Preferred Stock, Shares Issued (in shares)   0 0    
Preferred Stock, Shares Outstanding, Ending Balance (in shares)   0 0    
Research and Development Expense, Total | $   $ 895,000 $ 1,243,000 $ 1,267,000  
Advertising Expense | $   $ 537,000 $ 436,000 $ 297,000  
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)   0   337,100  
Undesignated Shares [Member]          
Preferred Stock, Shares Authorized (in shares)   5,000,000      
Series B Preferred Stock [Member]          
Preferred Stock, Shares Authorized (in shares)   500,000      
Preferred Stock, Shares Issued (in shares)   0      
Preferred Stock, Shares Outstanding, Ending Balance (in shares)   0      
Share Repurchase Program [Member]          
Stock Repurchased During Period, Shares (in shares)   0      
Patents [Member]          
Finite-Lived Intangible Asset, Useful Life (Year)   20 years 20 years    
Patents [Member] | Maximum [Member]          
Finite-Lived Intangible Asset, Useful Life (Year)   20 years